Compositions, kits, and methods for identification, assessment, prevention, and therapy of colon cancer

Abstract

The invention relates to newly discovered nucleic acid molecules and proteins associated with colon cancer. Compositions, kits, and methods for detecting, characterizing, preventing, and treating human colon cancers are provided.

Description

FIELD OF THE INVENTION

[0002] The field of the invention is colon cancer, including diagnosis, characterization, management, and therapy of colon cancer, particularly metastatic colon cancer.

BACKGROUND OF THE INVENTION

[0003] The increased number of cancer cases reported in the United States, and, indeed, around the world, is a major concern. Currently there are only a handful of detection and treatment methods available for specific types of cancer, and these provide no absolute guarantee of success. In order to be most effective, these treatments require not only an early detection of the malignancy, but also a reliable assessment of the severity of the malignancy.

[0004] Colon and rectal cancers are malignant conditions which occur in the corresponding segments of the large intestine. These cancers are sometimes referred to jointly as “colorectal cancer” (CRC), and, in many respects, the diseases are considered identical. The major differences between them are the sites where the malignant growths occur and the fact that treatments may differ based on the location of the tumors.

[0005] More than 95 percent of cancers of the colon and rectum are adenocarcinomas, which develop in glandular cells lining the inside (lumen) of the colon and rectum. In addition to adenocarcinomas, there are other rarer types of cancers of the large intestine: these include carcinoid tumors usually found in the appendix and rectum; gastrointestinal stromal tumors found in connective tissue in the wall of the colon and rectum; and lymphomas, which are malignancies of immune cells in the colon, rectum and lymph nodes. As with other malignant conditions, a number of genetic abnormalities have been associated with colon tumors (Bos et al, (1987) Nature 327:293-297; Baker et al, (1989) 244:217-221; Nishisho et al, (1991) 253:665-669).

[0006] Colon cancer is the third leading cause of cancer deaths in the United States. Each year over 100,000 new cases are diagnosed, and 50,000 patients die from the disease. In large part this death rate is due to the inability to diagnose the disease at an early stage (Wanebo (1993) Colorectal Cancer, Mosby, St. Louis Mo.). In fact, the prognosis for a case of colon cancer is vastly enhanced when malignant tissue is detected at the early stage known as polyps. Simple removal of malignant polyps (polypectomy) through colonoscopy is now routine, and curing the condition from this procedure is effectively guaranteed. However, early detection of polyps and tumors depends on diligent and ongoing examination of patients at risk. The most reliable detection procedures to date include fecal occult blood tests, sigmoidoscopy, barium enema X-ray, digital rectal exam, and colonoscopy. Normally a malignant colon cancer will not cause noticeable symptoms (e.g., bowel obstruction, abdominal pain, anemia) until it has reached an advanced and far more serious stage of malignancy. At these stages, only risky and invasive procedures are available, including chemotherapy, radiation therapy, and colonectomy.

[0007] It would therefore be desirable to provide methods and reagents for the early diagnosis, staging, prognosis, monitoring, and treatment of diseases associated with colon cancer, or to indicate a predisposition to such for preventative measures.

SUMMARY OF THE INVENTION

[0008] The invention relates to colon cancer markers n1-n333 (hereinafter “markers” or “markers of the inventions”), which are listed in Table 1 (markers n1-n319 and SEQ ID NOs:1-15) and Table 2 (markers n320-n333 and SEQ ID NOs:16-29). The markers of the invention are over-expressed in metastasized colon tumor tissues as compared to normal colon and/or liver tissues. The invention provides nucleic acids and proteins that are encoded by or correspond to the markers (hereinafter “marker nucleic acids” and “marker proteins,” respectively). The invention further provides antibodies, antibody derivatives and antibody fragments which bind specifically marker proteins and/or fragments of the marker proteins.

[0009] The invention also relates to various methods, reagents and kits for diagnosing, staging, prognosing, monitoring and treating colon cancer. “Colon cancer” as used herein includes carcinomas, (e.g., carcinoma in situ, invasive carcinoma, metastatic carcinoma) and early stage malignant conditions (e.g., adenomatous polyps). In one aspect, the invention relates to various diagnostic, monitoring, test and other methods related to colon cancer detection and therapy. In one embodiment, the invention provides a diagnostic method of assessing whether a patient has colon cancer or has higher than normal risk for developing colon cancer, comprising the steps of comparing the level of expression of a marker of the invention in a patient sample and the normal level of expression of the marker in a control, e.g., a sample from a patient without colon cancer. A significantly higher level of expression of the marker in the patient sample as compared to the normal level is an indication that the patient is afflicted with colon cancer or has higher than normal risk for developing colon cancer, particularly metastasized colon cancer

[0010] According to the invention, the markers are selected such that the positive predictive value of the methods of the invention is at least about 10%, preferably about 25%, more preferably about 50% and most preferably about 90%. Also preferred for use in the methods of the invention are markers that are differentially expressed, as compared to normal colon cells or normal liver cells, by at least two-fold in at least about 20%, more preferably about 50% and most preferably about 75% of any of the following conditions, for example, stage Tis colon cancer patients, stage T0 colon cancer patients, stage T1 colon cancer patients, stage T2 colon cancer patients, stage T3 colon cancer patients, stage T4 colon cancer patients.

[0011] In a preferred diagnostic method of assessing whether a patient is afflicted with colon cancer, particularly metastasized colon cancer, (e.g., new detection (“screening”), detection of recurrence, reflex testing), the method comprises comparing:

[0012] a) the level of expression of a marker of the invention in a patient sample, and

[0013] b) the normal level of expression of the marker in a control non-colon cancer sample.

[0014] A significantly higher level of expression of the marker in the patient sample as compared to the normal level is an indication that the patient is afflicted with colon cancer, particularly metastasized colon cancer

[0015] The invention also provides diagnostic methods for assessing the efficacy of a therapy for inhibiting colon cancer, particularly metastasized colon cancer, in a patient. Such methods comprise comparing:

[0016] a) expression of a marker of the invention in a first sample obtained from the patient prior to providing at least a portion of the therapy to the patient, and

[0017] b) expression of the marker in a second sample obtained from the patient

[0018] following provision of the portion of the therapy.

[0019] A significantly lower level of expression of the marker in the second sample relative to that in the first sample is an indication that the therapy is efficacious for inhibiting colon cancer, particularly metastasized colon cancer, in the patient.

[0020] It will be appreciated that in these methods the “therapy” may be any therapy for treating colon cancer including, but not limited to, chemotherapy, radiation therapy, surgical removal of tumor tissue, gene therapy and biologic therapy such as the administering of antibodies and chemokines. Thus, the methods of the invention may be used to evaluate a patient before, during and after therapy, for example, to evaluate the reduction in tumor burden.

[0021] In a preferred embodiment, the diagnostic methods are directed to therapy using a chemical or biologic agent. These methods comprise comparing:

[0022] a) expression of a marker of the invention in a first sample obtained from the patient and maintained in the presence of the chemical or biologic agent, and

[0023] b) expression of the marker in a second sample obtained from the patient and maintained in the absence of the agent.

[0024] A significantly lower level of expression of the marker in the second sample relative to that in the first sample is an indication that the agent is efficacious for inhibiting colon cancer, particularly metastasized colon cancer, in the patient. In one embodiment, the first and second samples can be portions of a single sample obtained from the patient or portions of pooled samples obtained from the patient.

[0025] The invention additionally provides a monitoring method for assessing the progression of colon cancer, particularly metastasized colon cancer, in a patient, the method comprising:

[0026] a) detecting in a patient sample at a first time point, the expression of a marker of the invention;

[0027] b) repeating step a) at a subsequent time point in time; and

[0028] c) comparing the level of expression detected in steps a) and b), and

[0029] therefrom monitoring the progression of colon cancer in the patient.

[0030] A significantly higher level of expression of the marker in the sample at the subsequent time point from that of the sample at the first time point is an indication that the colon cancer, particularly metastasized colon cancer, has progressed, whereas a significantly lower level of expression is an indication that the colon cancer, particularly metastasized colon cancer, has regressed.

[0031] The invention further provides a diagnostic method for determining whether colon cancer has metastasized or is likely to metastasize in the future, the method comprising comparing:

[0032] a) the level of expression of a marker of the invention in a patient sample, and

[0033] b) the normal level (or non-metastatic level) of expression of the marker in a control sample.

[0034] A significantly higher level of expression in the patient sample as compared to the normal level (or non-metastatic level) is an indication that the colon cancer has metastasized or is likely to metastasize in the future.

[0035] The invention moreover provides a test method for selecting a composition for inhibiting colon cancer, particularly metastasized colon cancer, in a patient. This method comprises the steps of:

[0036] a) obtaining a sample comprising cancer cells from the patient;

[0037] b) separately maintaining aliquots of the sample in the presence of a plurality of test compositions;

[0038] c) comparing expression of a marker of the invention in each of the aliquots; and

[0039] d) selecting one of the test compositions which significantly reduces the level of expression of the marker in the aliquot containing that test composition, relative to the levels of expression of the marker in the presence of the other test compositions.

[0040] The invention additionally provides a test method of assessing the colon carcinogenic potential of a compound. This method comprises the steps of:

[0041] a) maintaining separate aliquots of colon cells in the presence and absence of the compound; and

[0042] b) comparing expression of a marker of the invention in each of the aliquots.

[0043] A significantly higher level of expression of the marker in the aliquot maintained in the presence of the compound, relative to that of the aliquot maintained in the absence of the compound, is an indication that the compound possesses colon carcinogenic potential.

[0044] In addition, the invention further provides a method of inhibiting colon cancer, particularly metastasized colon cancer, in a patient. This method comprises the steps of:

[0045] a) obtaining a sample comprising colon cancer cells from the patient;

[0046] b) separately maintaining aliquots of the sample in the presence of a plurality of compositions;

[0047] c) comparing expression of a marker of the invention in each of the aliquots; and

[0048] d) administering to the patient at least one of the compositions which significantly lowers the level of expression of the marker in the aliquot containing that composition, relative to the levels of expression of the marker in the presence of the other compositions.

[0049] In the aforementioned methods, the samples or patient samples comprise cells obtained from the patient. The cells may be from a liver or colon tissue sample, or found in a colon smear collected, for example, by colonoscopy. In another embodiment, the sample is a body fluid. Such fluids include, for example, blood fluids, stool, colon lavage fluids and lymph fluids. In a further embodiment, the patient sample is in vivo.

[0050] According to the invention, the level of expression of a marker of the invention in a sample can be assessed, for example, by detecting the presence in the sample of:

[0051] a corresponding marker protein or a fragment of the protein (e.g. by using a reagent, such as an antibody, an antibody derivative, an antibody fragment or single-chain antibody, which binds specifically with the protein or protein fragment)

[0052] a corresponding marker nucleic acid or a fragment of the nucleic acid (e.g. by contacting transcribed polynucleotides obtained from the sample or cDNA derived therefrom with a substrate having affixed thereto one or more nucleic acids having the entirety or a segment of the marker's cDNA sequence, or a complement thereof)

[0053] a metabolite which is produced directly (i.e., catalyzed) or indirectly by a corresponding marker protein.

[0054] According to the invention, any of the aforementioned methods may be performed using a plurality (e.g. 2, 3, 5, or 10 or more) of colon cancer markers, including colon cancer markers known in the art. In such methods, the level of expression in the sample of each of a plurality of markers, at least one of which is a marker of the invention, is compared with the normal level of expression of each of the plurality of markers in samples of the same type obtained from control humans not afflicted with colon cancer. A significantly altered (i.e., increased or decreased as specified in the above-described methods using a single marker) level of expression in the sample of one or more markers of the invention, or some combination thereof, relative to that marker's corresponding normal or control level, is an indication that the patient is afflicted with colon cancer. For all of the aforementioned methods, the marker(s) are preferably selected such that the positive predictive value of the method is at least about 10%.

[0055] In a further aspect, the invention provides an antibody, an antibody derivative, or an antibody fragment, which binds specifically with a marker protein or a fragment of the protein. The invention also provides methods for making such antibody, antibody derivative, and antibody fragment. Such methods may comprise immunizing a mammal with a protein or peptide comprising the entirety, or a segment of 10 or more amino acids, of a marker protein, wherein the protein or peptide may be obtained from a cell or by chemical synthesis. The methods of the invention also encompass producing monoclonal and single-chain antibodies, which would further comprise isolating splenocytes from the immunized mammal, fusing the isolated splenocytes with an immortalized cell line to form hybridomas, and screening individual hybridomas for those that produce an antibody that binds specifically with a marker protein or a fragment of the protein.

[0056] In another aspect, the invention relates to various diagnostic and test kits. In one embodiment, the invention provides a kit for assessing whether a patient is afflicted with colon cancer, particularly metastasized colon cancer. The kit comprises a reagent for assessing expression of a marker of the invention. In another embodiment, the invention provides a kit for assessing the suitability of a chemical or biologic agent for inhibiting colon cancer, particularly metastasized colon cancer, in a patient. Such a kit comprises a reagent for assessing expression of a marker of the invention, and may also comprise one or more of such agents. In a further embodiment, the invention provides kits for assessing the presence of colon cancer cells, particularly metastasized colon cancer cells, or treating colon cancers, particularly metastasized colon cancers. Such kits comprise an antibody, an antibody derivative, or an antibody fragment, which binds specifically with a marker protein, or a fragment of the protein. Such kits may also comprise a plurality of antibodies, antibody derivatives, or antibody fragments wherein the plurality of such antibody agents binds specifically with a marker protein, or a fragment of the protein.

[0057] In an additional embodiment, the invention also provides a kit for assessing the presence of colon cancer cells, particularly metastasized colon cancer cells, wherein the kit comprises a nucleic acid probe that binds specifically with a marker nucleic acid or a fragment of the nucleic acid. The kit may also comprise a plurality of probes, wherein each of the probes binds specifically with a marker nucleic acid, or a fragment of the nucleic acid.

[0058] In a further aspect, the invention relates to methods for treating a patient afflicted withor at risk of developing colon cancer, particularly metastasized colon cancer. Such methods may comprise reducing the expression and/or interfering with the biological function of a marker of the invention. In one embodiment, the method comprises providing to the patient an antisense oligonucleotide or polynucleotide complementary to a marker nucleic acid, or a segment thereof. For example, an antisense polynucleotide may be provided to the patient through the delivery of a vector that expresses an anti-sense polynucleotide of a marker nucleic acid or a fragment thereof. In another embodiment, the method comprises providing to the patient an antibody, an antibody derivative, or antibody fragment, which binds specifically with a marker protein or a fragment of the protein.

[0059] It will be appreciated that the methods and kits of the present invention may also include known cancer markers including known colon cancer markers. It will further be appreciated that the methods and kits may be used to identify other types of cancers such as breast, ovarian, cervical, prostate and lung cancers.

DETAILED DESCRIPTION OF THE INVENTION

[0060] The invention relates to newly discovered colon cancer markers n1-n319 associated with the cancerous state of colon cells. It has been discovered that the higher than normal level of expression of any of these markers or combination of these markers correlates with the presence of metastasized colon cancer. Methods are provided for detecting the presence of colon cancer in a sample, the absence of colon cancer in a sample, the stage of a colon cancer, and with other characteristics of colon cancer that are-relevant to prevention, diagnosis, characterization, and therapy of colon cancer, particularly metastasized colon cancer, in a patient. Methods of treating colon cancer are also provided.

[0061] Tables 1 and 2 list markers of the invention, which are over-expressed in metastasized colon cancer cells compared to normal (i.e., non-cancerous) colon cells or normal liver cells and provides, if applicable, the gene name of each marker, the sequence listing identifier of the cDNA sequence of a mRNA encoded by each marker. Table 1 also provides, if applicable, the identifier number(s) of one or more IMAGE clones containing an insert comprising a partial or complete cDNA of a mRNA encoded by or corresponding to the marker; and the National Center for Biotechnology Information (NCBI) Protein and Nucleotide Database accession numbers of information entries concerning the IMAGE clone cDNA insert(s), and a mRNA and protein encoded by or corresponding to the marker, including, under GI numbers, their respective nucleotide and amino acid sequences. The NCBI Protein and Nucleotide Database contains sequence data from the translated DNA coding regions of GenBank, EMBL and DDBJ as well as protein sequences submitted to PIR, SWISSPROT, PRF, Protein Data Bank (PDB) (sequences from solved structures) and RefSeq (non-redundant curated sequences). All database records set forth in Table 1 are expressly incorporated by reference.

[0062] The markers of Table 1 (markers n-1-n319 and SEQ ID NOs:1-15) were expressed at higher levels in some of five metastatic colon adenocarcinoma samples from sites of liver metastases compared to the expression in normal colon tissue samples and normal liver tissue samples. Markers n1-n319 are useful in detecting primary and metastatic colon tumors. Markers n1-n84 and n305-n307 are particularly useful in detecting metastatic colon tumors. Markers n85-n304 and n308-n319 are particularly useful in detecting metastatic colon tumors and primary colon tumors that are likely to metastasize.

[0063] Table 2 lists markers of the invention (markers n320-n333 and SEQ ID NOs:16-29), which are over-expressed in metastasized colon cancer cells as compared to normal (i.e., non-cancerous) colon and liver cells. The Sequence Listing identifier number of the cDNA sequence of a RNA transcript encoded by each marker (SEQ ID NOs:1-29) is also provided. Markers n320-n333 are useful in detecting metastatic colon tumors and primary colon tumors that express markers associated with metastatic disease.

TABLE 1
			NCBI
			Accession	NCBI
			# of	GI# of					SEQ
		IMAGE	IMAGE	IMAGE	NCBI		NCBI	NCBI	ID
		Clone	clone	clone	nuc	NCBI	protein	protein	NO
Marker	Gene Name	ID	insert	insert	accession #	nuc GI#	accession #	GI#	(nt)
n1	G protein	796624	AA460529	2185649	NM_017938.1	8923642	NP_060408	8923643
	coupled		AA460530	2185650
	receptor 49
n2	matrix	470393	AA031513	1501467
	metalloprote		AA031514	1501468
	inase 7
	(matrilysin)
n3	solute	363003	AA018866	1482466	NM_016354.1	7706516	NP_057438	7706517
	carrier		AA019155	1482564
	family 21,
	member 12
n4	nuclear	1034644	AA779843	2839174	NM_004289.3	5731346	NP_004280	5731347
	factor	345069	W74359	1384665
	(erythroid-	345069	W76339	1386789
	derived)2-	509564	AA045573	1525318
	like 3
n5	SRY (sex	366815	AA029415	1496958
	determining	366815	AA029490	1496957
	region Y)-	250869	N23605	1137755
	box 4	250869	N23606	1137756
n6	hypothetical	595697	AA167381	1745758	NM_017763.1	8923298	NP_060233	8923299
	protein		AA167382	1745759
	FLJ20315
n7	glutaminase	256895	N39485	1162692
n8	prostate	256895	N26311	1140659
	differentiation
	factor
n9	nebulette	796643	AA460120	2185505
			AA461473	2185337
n10	ectodermal-	213651	H72122	1043938	NM_003633.1	4505460	NP_003624	4505461
	neural	213651	H72225	1044041
	cortex (with	180512	R85090	943496
	BTB-like
	domain)
n11	unnamed	1585327	AA976642	3154088
n12	unnamed	509564	AA045574	1525319	NM_004289.3
n13	gamma-	809588	AA455800	2178576	NM_003878.1	4503986	NP_003869	4503987
	glutamyl		AA456621	2179197
	hydrolase
n14	carbonic	1643566	AI023541	3238585
	anhydrase
	IX
n15	matrix	196612	R92994	965348	NM_002426.1	4505206	NP_002417	4505207
	metalloprote		R93037	965391
	inase 12
n16	S100	135221	R32848	788691
	calcium-		R32952	788795
	binding
	protein P
n17	unnamed	685801	AA262080	1898204
n18	solute	685801	AA255695	1892633	NM_001046.1	4506974	NP_001037	4506975
	carrier
	family 12,
	member 2
n19	epithelial	504927	AA151002	1722513	NM_005764.1	5031656	NP_005755	5031657
	protein up-		AA151092	1722622
	regulated in
	carcinoma,
	membrane
	associated
	protein 17
n20	collagen,	153646	R48843	810869	NM_000088.1	4502944	NP_000079	4502945
	type I, alpha		R48844	810870
	1
n21	secreted	378461	AA775616	2834950
	phosphopro-
	tein 1
	(osteopontin)
n22	novel	none							1
n23	unnamed	753428	AA406425	2064410
			AA410434	2069540
n24	novel	none							2
n25	novel	none							3
n26	ribosomal	244147	N72048	1228760
	protein S3A
n27	matrix	487296	AA040568	1516901	NM_005940.1	5174580	NP_005931	5174581
	metalloprote	487296	AA045500	1523736
	inase 11	1574438	AA954935	3118630
	(stromelysin
	3)
n28	kallikrein 10	810960	AA459401	2184308	NM_002776.1	4506156	NP_002767	4506157
		810960	AA459626	2184533
		809616	AA458489	2183396
n29	novel	none							4
n30	unnamed	none							5
n31	unnamed	1585952	AA974305	3149485
n32	thrombospon-	191664	H38013	907512	NM_003247.1	4507486	NP_003238	4507487
	din 2		H38240	907739
n33	novel	none							6
n34	DKFZP434	454970	AA676625	2657147
	G032
	protein
n35	PMEPA1	511233	AA088701	1634222	NM_020182.1	9910497	NP_064567	9910498
	protein	511233	AA088767	1634332
		841141	AA486591	2216755
		841141	AA487031	2217195
n36	biglycan	144786	R77226	851858
		144786	R77227	851859
		244147	N51018	1192184
n37	v-myc avian	812965	AA464600	2189484
	myelocytom
	atosis viral
	oncogene
	homolog
n38	novel	none							7
n39	pim-1	292726	N63635	1211464	NM_002648.1	4505810	NP_002639	4505811
	oncogene		N80481	1243182
n40	SRY (sex-	753184	AA400464	2054600	NM_000346.1	4557852	NP_000337	4557853
	determining		AA400739	2054627
	region Y)-
	box 9
n41	cadherin 3,	773301	AA425217	2106125	NM_001793.1	4502722	NP_001784	4502723
	P-cadherin		AA425556	2106296
n42	epiregulin	271744	N31585	1151984	NM_001432.1	4557566	NP_001423	4557567
			N42596	1167026
n43	ubiquitin	146882	R80790	857071	NM_007019.1	5902145	NP_008950	5902146
	carrier	146882	R80990	857271
	protein E2-	769921	AA430504	2111094
	C
n44	S-	840364	AA485626	2214845	NM_000687.1	9951914	NP_000678	9951915
	adenosylho
	mocysteine
	hydrolase
n45	TH1	1591898	AA977342	3154788
	drosophila
	homolog
n46	KIAA1533	843054	AA485976	2216192
	protein		AA488602	2216033
n47	unnamed	147826	R81486	858089
			R81726	858329
n48	amphiregulin	1410444	AA857163	2945465	NM_001657.1	4502198	NP_001648	4502199
	(schwanno
	ma-derived
	growth
	factor)
n49	osteoblast	897910	AA598653	2432236	NM_006475.1	5453833	NP_006466	5453834
	specific	2028722	AI262129	3870332
	factor 2
n50	interferon	509641	AA058323	1551160	NM_003641.1	4504580	NP_003632	4504581
	induced	509641	AA058453	1551263
	transmem-	755599	AA419251	2078964
	brane protein	755599	AA419286	2079016
	1 (9-27)
n51	unnamed	811785	AA463463	2188347
n52	S100	810612	AA464731	2189615
	calcium-
	binding
	protein A11
	(calgizzarin)
n53	solute	207358	H58872	1011704	NM_006516.1	5730050	NP_006507	5730051
	carrier	207358	H58873	1011705
	family 2,	453589	AA679565	2660087
	member 1	25389	R11688	764423
		25389	R17667	771277
n54	unnamed	1639660	AI024950	3240563
n55	unnamed	1612075	AA995447	3181936
n56	unnamed	745296	AA625574	2537961
n57	unnamed	309895	N94488	1266797
			W23938	1300753
n58	unnamed	162077	H25689	894812
		162077	H26271	895394
		753071	AA436565	2141479
		753071	AA436592	2141506
n59	novel	none							8
n60	pleckstrin	667883	AA258396	1893538
	homology-	1635066	AA995175	3181664
	like domain,
	family A,
	member 1
n61	novel	none							9
n62	putative	949988	AA600214	2433839	NM_018407.1	8923827	NP_060877	8923828
	integral
	membrane
	transporter
n63	phospho-	949939	AA599187	2432812	NM_000291.1	4505762	NP_000282	4505763
	glycerate
	kinase 1
n64	hypothetical	813645	AA447746	2161416	NM_019058.1	9506686	NP_061931	9506687
	protein	813645	AA453677	2167346
	FLJ20500	221707	H92504	1088082
n65	unnamed	360644	AA015818	1476848
			AA015819	1476849
n66	unnamed	258235	N26401	1140749
n67	unnamed	771301	AA443637	2156312
n68	ISG-54K	none			M14660	186559	P09913	124488
	gene
n69	carcino-	509823	AA054073	1545283
	embryonic		AA054457	1545382
	antigen-
	related cell
	adhesion
	molecule 6
n70	novel	none							10
n71	eukaryotic	198093	R93621	967787	NM_003908.1	4503504	NP_003899	4503505
	translation		R93622	967788
	initiation
	factor 2,
	subunit 2
n72	hypothetical	77577	T58873	660710
	protein
	FLJ23306
n73	FOS-like	77577	T58932	660769
	antigen 2
n74	unnamed	858188	AA633866	2557080
n75	novel	none							11
n76	unnamed	753198	AA406348	2064331
			AA406456	2064441
n77	novel	none							12
n78	solute	586990	AA133655	1690641	NM_000617.1	1083516	NP_000608	10835169
	carrier	586990	AA133656	1690642		8
	family 11,	127580	R09378	761301
	member 2	127580	R09379	761302
n79	hypothetical	843045	AA488420	2215851	NM_017671.1	8923115	NP_060141	8923116
	protein		AA488559	2215990
	FLJ20116
n80	thymidine	379920	AA778098	2837499	NM_003258.1	4507518	NP_003249	4507519
	kinase 1,
	soluble
n81	potassium	756708	AA443903	2156578	NM_002250.1	4504858	NP_002241	4504859
	inter-
	mediate/
	small
	conductance
	calcium-
	activated
	channel,
	subfamily
	N, member
	4
n82	nudix	756502	AA443998	2156673	NM_002452.1	4505274	NP_002443	4505275
	(nucleoside		AA444020	2156695
	diphosphate
	linked
	moiety X-
	type) motif
	1
n83	non-	845363	AA644092	2569310	NM_000269.1	4557796	NP_000260	4557797
	metastatic
	cells 1,
	protein
	(NM23A)
	expressed in
n84	ribosomal	192242	H41165	917217	NM_001022.1	4506694	NP_001013	4506695
	protein S19
n85	unnamed	487035	AA043979	1521837
			AA044015	1521891
n86	calmodulin	855707	AA663941	2617932
	2
n87	DKFZP586	767068	AA424504	2103465
	G1517
	protein
n88	unnamed	154929	AI732283	5053396
			AI820704	5439783
			R54983	819239824723
			R55428
n89	glutathione	587847	AA135152	1696253
	peroxidase 2		AA135289	1696365
n90	ribosomal	244911	N54526	1195846
	protein L39		N76229	1238807
n91	unnamed	878193	AA775755	2835089
n92	unnamed	645161	AA206566	1802059
			AA206615	1801995
n93	unnamed	780938	AA429804	2113028
			AA446138	2158803
n94	unnamed	292982	N69100	1225261
			N90620	1443947
n95	unnamed	none							13
n96	unnamed	838518	AA481728	2211280
			AA481729	2211281
n97	unnamed	364896	AA024494	1489454
			AA024617	1489558
n98	unnamed	609950	AA174105	1754247
			AA174106	1754248
n99	small	950482	AA599116	2432741
	nuclear
	ribonucleo-
	protein
	polypeptide
	s B and B1
n100	unnamed	121154	T96935	735559
			T97044	735668
n101	karyopherin	882510	AA676460	2656982
	alpha 2
n102	melanoma	1475476	AA857809	2946111
	antigen,
	family A, 4
n103	unnamed	825809	AA491328	2220501
			AA505135	2241295
n104	unnamed	362686	AA018617	1481891
			AA018618	1481892
n105	unnamed	51831	H22949	891644
			H24131	892826
n106	unnamed	435919	AA701948	2705061
n107	unnamed	295106	N71631	1228343
			W01645	1273644
n108	unnamed	213575	H70162	1040368
			H70163	1040369
n109	PRO0132	234527	H77553	1055642	NM_014116.1	7662525	NP_054835	7662526
	protein		H77554	1055643
n110	unnamed	26196	R13718	766794
			R20755	775536
n111	unnamed	123065	T98528	748265
			T98529	748266
n112	unnamed	321945	W37504	1319098
			W37600	1319214
n113	unnamed	143535	R75639	850321
			R75743	850425
n114	unnamed	120528	T95320	733944
			T95404	734028
n115	G protein-	878571	AA775249	2834583
	coupled
	receptor 56
n116	unnamed	897745	AA599007	2432047
n117	transmem-	840567	AA487893	2215324
	brane 4		AA488005	2215436
	superfamily
	member 1
n118	transferrin	841703	AA487593	2217757	NM_003234.1	4507456	NP_003225	4507457
	receptor		AA488721	2218323
n119	unnamed	73756	T54643	656504
			T54725	656586
n120	unnamed	34839	R19756	774390
			R45175	823529
n121	unnamed	245010	N52641	1193807
			N72369	1229473
n122	CDC20	898062	AA598776	2432448
n123	unnamed	346255	W74070	1384291
			W79381	1390036
n124	unnamed	392607	AA708240	2718158
n125	unnamed	853491	AA663551	2617542
n126	glypican 3	878564	AA775872	2835206	NM_004484.2	5360213	NP_004475	4758462
n127	CDC28	359119	AA010065	1471093	NM_001827.1	4502858	NP_001818	4502859
	protein	725454	AA292964	1940859
	kinase 2	725454	AA397813	2051021
n128	methyltrans-	755239	AA422058	2100891
	ferase-like 1
n129	non-	755239	AA422139	2101007	NM_002512.1	4505408	NP_002503	4505409
	metastatic
	cells 2,
	protein
	(NM23B)
n130	ribophorin	1610448	AA991856	3178738
	II
n131	unnamed	201440	R99105	985706
			R99647	986248
n132	unnamed	713114	AA282985	1925918
			AA283154	1926088
n133	unnamed	214521	H73186	1046688
			H73857	1046791
n134	ribosomal	1492147	AA888182	3003857	NM_001007.1	4506724	NP_000998	4506725
	protein S4,
	X-linked
n135	unnamed	503675	AA131450	1692956
			AA131562	1693051
n136	unnamed	506269	AA706114	2716032
n137	unnamed	415111	W93147	1422516
			W95009	1424129
n138	glyoxalase I	491001	AA136710	1697920
			AA136808	1698017
n139	Homo	1032004	AA610004	2458432
	sapiens
	putative
	oncogene
	protein
	h1c14-06-p
n140	translocase	810452	AA457118	2179838
	of outer
	mitochon-
	drial
	membrane
	34
n141	renal tumor	289666	N62873	1210702
	antigen		N77779	1240480
n142	unnamed	41391	R56123	826229
			R56515	826621
n143	cathepsin H	841470	AA487231	2217395	NM_004390.1	4758095	NP_004381	4758096
			AA487346	2217510
n144	v-rel avian	258589	N32146	1152545	NM_002908.1	4506472	NP_002899	4506473
	reticuloendo		N56815	1200705
	theliosis
	viral
	oncogene
	homolog
n145	unnamed	149245	R82522	861913
			R82582	861973
n146	Sp3	263840	N28494	1146730
	transcription
	factor
n147	unnamed	263840	H99768	1124436
n148	high-	782811	AA448261	2161931	NM_002131.1	4504432	NP_002122	4504433
	mobility
	group
	(nonhistone
	chromosomal
	protein)
	isoforms I
	and Y
n149	hypothetical	292936	N63744	1211573	NM_018101.1	8922437	NP_060571	8922438
	protein		N91096	1444423
	FLJ10468
n150	unnamed	726889	AA398430	2051539
			AA403053	2056802
n151	unnamed	129922	R11432	764167
			R19183	772793
n152	multifunc-	273546	N33274	1153673	NM_006452.1	5453538	NP_006443	5453539
	tional		N44764	1185930
	polypeptide
	similar to
	SAICAR
	synthetase
	and AIR
	carboxylase
n153	unnamed	1046495	AA621138	2525077
n154	unnamed	364547	AA022910	1487027
			AA022978	1487077
n155	unnamed	429685	AA011598	1472705
			AA011665	1472751
n156	unnamed	1473045	AA873427	2969549
n157	unnamed	246824	N59090	1202980
			N59494	1203384
n158	unnamed	none							14
n159	unnamed	209118	H63518	1018319
			H63919	1018720
n160	unnamed	234094	H67005	1025745
			H67006	1025746
n161	unnamed	48236	H11986	876806
			H11987	876807
n162	zinc finger	785941	AA448571	2162241
	protein 278		AA449718	2163468
n163	unnamed	294687	N71304	1227884
			W01575	1273629
n164	unnamed	824128	AA490612	2219785
n165	unnamed	867580	AA780560	2839891
n166	unnamed	430971	AA678347	2658869
n167	transcrip-	137535	R38345	795801
	tional		R39430	796886
	intermediary
	factor 1
n168	unnamed	726893	AA398431	2051540
			AA403054	2056803
n169	urocortin	745330	AA625641	2538028
n170	normal	none			M29541	189103	P40199	730124
	cross-
	reacting
	antigen
	(CD66C)
n171	zinc finger	703844	AA278839	1920360	NM_016220.1	7706774	NP_057304	7706775
	protein		AA279103	1920586
	(ZFD25)
n172	unnamed	429439	AA007623	1463609
n173	glucocorti-	none			AF125303	4558500	AAD22634	4558501
	coid induced
	TNFR-
	related
	protein
	ligand
	(TNFSF18)
n174	flavin	309224	N93853	1266162
	containing		W40326	1324127
	mono-
	oxygenase 1
n175	unnamed	305203	N94950	1267221
			W19586	1295485
n176	eukaryotic	42452	R59752	830447	NM_001568.1	4503520	NP_001559	4503521
	translation	42452	R61297	831992
	initiation	856961	AA669674	2631173
	factor 3,
	subunit 6
n177	membrane	796994	AA463497	2188381
	cofactor		AA463544	2188428
	protein
	(CD46)
n178	HSPC056	135253	R31034	786877	NM_014154.1	7661763	NP_054873	7661764
	protein		R31524	787367
n179	unnamed	243199	H94492	1102125
			H94578	1102211
n180	unnamed	194971	R91086	958626
			R91087	958627
n181	unnamed	199602	R96585	982245
			R96586	982246
n182	unnamed	204688	H57272	1010104
			H57273	1010105
n183	Re1A-	246704	N57743	1201633	NM_006663.1	5730000	NP_006654	5730001
	associated		N59710	1203600
	inhibitor
n184	unnamed	293358	N68821	1224982
			N92035	1264344
n185	unnamed	752612	AA417774	2079575
			AA419470	2079188
n186	laminin,	460403	AA677534	2658056
	gamma 2
n187	E2F	768260	AA424949	2107037
	transcription		AA424950	2107038
	factor 1
n188	KIAA0588	none			AB011160	3043699	BAA25514	3043700
	protein,
	protocadherin
	gamma
	A12
n189	unnamed	66420	R16069	767878
n190	unnamed	47186	H10403	875225
			H10611	875433
n191	unnamed	813661	AA447764	2161434
n192	tripartite	813661	AA453694	2167363
	repeat
	protein
	TRIM2
	(KIAA0517)
n193	hypoxanthine	280507	N47311	1188477	NM_000194.1	4504482	NP_000185	4504483
	phosphoribo-		N47312	1188478
	syltransferase
	1
n194	lactate	897567	AA489611	2219213	NM_005566.1	5031856	NP_005557	5031857
	dehydrogen		AA497029	2230350
	ase A
n195	unnamed	203888	H56640	1005284
			H56717	1005361
n196	unnamed	214512	H73178	1046680
			H73852	1046786
n197	CXC	730970	AA416552	2077513	NM_022059.1	1154576	NP_071342	11545765
	chemokine					4
	ligand 16
	(CXCL16)
n198	KIAA0748	294679	N71300	1227880
	gene		W01608	1273625
	product
n199	unnamed	111348	T84275	712563
			T85161	713513
n200	unnamed	1239845	AA705977	2715895
n201	ART-4	824799	AA489080	2218682	NM_014062.1	7661531	NP_054781	7661532
	protein
n202	unnamed	294942	N71473	1228185
n203	unnamed	247177	N57906	1201796
n204	transmem-	252382	H87106	1068685
	brane 4
	superfamily
	member 6
n205	hypothetical	238689	H67236	1025976	NM_017688.1	8923147	NP_060158	8923148
	protein	238689	H81554	1059643
	FLJ20150	321908	W37679	1319293
		321908	W37680	1319294
		238689	W38021	1319615
		238689	W38022	1319616
n206	ras homolog	345680	W72033	1382413	NM_004675.1	4757771	NP_004666	4757772
	gene family,		W76278	1386720
	member I
n207	baculoviral	796694	AA460685	2185805	NM_001168.1	4502144	NP_001159	4502145
	IAP repeat-		AA460859	2185979
	containing 5
	(survivin)
n208	unnamed	768596	AA425056	2107189
			AA429233	2110844
n209	cystatin B	51814	H22919	891614
			H24099	892794
n210	unnamed	415326	W91896	1424479
			W92036	1424420
n211	unnamed	358699	W94246	1423387
			W94247	1423388
n212	unnamed	136502	R34343	791244
			R34454	791355
n213	unnamed	206937	R98709	985310
			R98934	985535
n214	unnamed	261163	H98200	1119085
			H98201	1119086
n215	unnamed	42807	R60134	830829
			R60135	830830
n216	alpha-	788180	AA453310	2166979	NM_014324.1	7656884	NP_055139	7656885
	methylacyl-		AA453562	2167231
	CoA
	racemase
n217	unnamed	28277	R14190	767266
			R37472	794928
n218	unnamed	757327	AA437094	2142008
n219	tumor	813189	AA456325	2179535
	differentially
	expressed
	1
n220	unnamed	212772	H69683	1039889
			H70099	1040305
n221	unnamed	38804	R36035	792936
			R49117	820187
n222	KIAA0618	288961	N62712	1210541
	gene		N78434	1241135
	product
n223	unnamed	795794	AA459851	2184758
			AA460404	2185617
n224	ribosomal	none			NM_000977	4506598	NP_000968	4506599
	protein L13
n225	unnamed	38477	R36299	793200
			R49587	820431
n226	unnamed	742672	AA401370	2053578
n227	cat eye	206816	R98055	983715	NM_017424.1	8393092	NP_059120	8393093
	syndrome		R98295	983955
	chromosome
	region,
	candidate 1
n228	unnamed	809657	AA454682	2177458
			AA456331	2178907
n229	CGI-72	382451	AA064627	1558871	NM_016018.1	7705782	NP_057102	7705783
	protein		AA064791	1558912
n230	unnamed	417761	W88725	1404207
n231	unnamed	744632	AA621302	2525241
n232	unnamed	67070	T70344	681492
			T70429	681577
n233	Human	433573	AA701655	2704820
	endogenous
	retrovirus
	envelope
	region
	mRNA
	(PL1)
n234	keratin 14	183602	H44051	920103	NM_000526.1	4504912	NP_000517	4504913
			H44127	920179
n235	keratin 13	none			AF049259	3603252	AAC35754	3603253
n236	calponin 2	713886	AA284568	1927532	NM_004368.1	4758017	NP_004359	4758018
			AA284856	1927415
n237	unnamed	1535611	AA918380	3058270
n238	unnamed	32496	R17996	771606
			R36749	793650
			R43486	820004
n239	unnamed	609930	AA169259	1747818
			AA169767	1748102
n240	unnamed	744945	AA625900	2538287
n241	ribosomal	178137	H46476	922528	NM_000995.1	4506636	NP_000986	4506637
	protein L34		H47015	923067
n242	unnamed	810993	AA485360	2214579
			AA485515	2214734
n243	hypothetical	246620	N53133	1194299	NM_018387.1	8922988	NP_060857	8922989
	protein		N58563	1202453
	FLJ11307
n244	solute	898227	AA598625	2432208
	carrier
	family 1,
	member 4
n245	unnamed	none							15
n246	unnamed	308105	N95322	1267592
			W24588	1301479
n247	unnamed	1632017	AA994691	3181180
n248	unnamed	296488	N70208	1226788
			W01059	1273049
n249	ribosomal	none			L06505	186799	AAA36157	186800
	protein L12
n250	TERA	815015	AA465096	2191263	NM_021238.1	1086404	NP_067061	10864049
	protein					8
n251	unnamed	452512	AA778756	2838087
n252	KIAA0255	756627	AA481480	2211032	NM_014742.1	7662027	NP_055557	7662028
	gene		AA481718	2211270
	product
n253	immediate	810724	AA457705	2180425	NM_003897.1	4503328	NP_003888	4503329
	early		AA480815	2210367
	response 3
n254	unnamed	366915	AA026588	1492874
			AA027147	1492816
n255	unnamed	566255	AA137095	1698331
			AA137096	1698332
n256	MyoD	33342	R44617	824005
	family
	inhibitor
n257	ribosomal	303048	N91584	1444911	NM_001845.1	7656984	NP_001836	7656985
	protein S6		W20479	1295192
n258	cyclin F	455128	AA676797	2657319
n259	unnamed	32576	R43535	821464
n260	hypothetical	32576	R20416	775050
	protein
	DKFZp761
	F241
n261	unnamed	40762	R56243	826349
			R56325	826431
n262	interleukin	1493390	AA894687	3031088
	enhancer
	binding
	factor 2,
	45kD
n263	unnamed	36367	R62460	834339
n264	UL16	36367	R25716	781851
	binding
	protein 2
n265	unnamed	32832	R18753	772363
			R43073	820134
n266	unnamed	46111	H09328	874150
			H09388	874210
n267	KIAA0460	49240	H15436	880256
	protein		H15492	880312
n268	unnamed	51548	H20826	889521	NM_002547.1	4505506	NP_002538.1	4505507
			H20876	889571
n269	ribosomal	66686	T67270	676710	NM_006013.1	5174430	NP_006004.1	5174431
	protein L10		T67271	676711
n270	PP2135	67741	T49634	651494
	protein		T49635	651495
n271	unnamed	71351	T47693	649673
			T47694	649674
n272	unnamed	73241	T56007	657868
n273	GDP-fucose	84586	T74039	690714
	transporter 1		T74413	691088
n274	unnamed	115223	T86602	714954
			T86603	714955
n275	G protein-	139304	R63714	835593	NM_005279.1	4885302	NP_005270.1	4885303
	coupled		R63760	835639
	receptor 1
n276	unnamed	194401	R83017	927861
			R83068	927945
n277	unnamed	201213	R99470	986071
			R99471	986072
n278	unnamed	203474	H55784	1004428
			H55878	1004522
n279	unnamed	221694	H92422	1088000
			H92639	1088217
n280	unnamed	223047	H86481	1068060
n281	unnamed	243659	N49902	1191068
			N50005	1191171
n282	unnamed	244323	N54803	1196123
			N75727	1238305
n283	TAR (HIV)	287745	N62244	1210073	NM_005646.1	5032156	NP_005637.1	5032157
	RNA-		N79334	1242035
	binding
	protein 1
n284	unnamed	293417	N63691	1211520
			N92134	1264443
n285	unnamed	293683	N63823	1211652
			N94181	1266490
n286	RAB1,	293715	N69689	1225850	NM_004161.1	4758987	NP_004152.1	4758988
	member		N94298	1266607
	RAS
	oncogene
	family
n287	hypothetical	294127	N69694	1225855	NM_022373.1	1164130	NP_071768.1	11641301
	protein		N71365	1227945		0
	FLJ22313		N99796	1271310
n288	adaptor-	323693	W44549	1330128
	related		W44558	1330069
	protein
	complex 1,
	sigma 1
	subunit
n289	unnamed	417393	W88942	1403848
			W89059	1403945
n290	pleiomorphic	460899	AA704187	2714105	NM_002657.2	6031195	NP_002648.1	4505859
	adenoma
	gene-like 2
n291	sorting	610113	AA169814	1748164	NM_003100.1	4507140	NP_003091.1	4507141
	nexin 2		AA171463	1750521
n292	unnamed	795614	AA460006	2184890
n293	unnamed	795677	AA459935	2184819
n294	tyrosylprotein	810937	AA459389	2184296	NM_003595.1	4507666	NP_003586.1	4507667
	sulfotransfer		AA459614	2184521
	ase 2
n295	KIAA1151	840777	AA486089	2216305
	protein		AA486151	2216367
n296	small	852913	AA668189	2629688	NM_003095.1	4507130	NP_003086.1	4507131
	nuclear
	ribonucleo-
	protein
	polypeptide
	F
n297	integral type	858152	AA633805	2557019	NM_007364.1	6679188	NP_031390.1	6679189
	I protein
n298	ribosomal	877835	AA625634	2538021	NM_007209.1	6005859	NP_009140.1	6005860
	protein L35
n299	ribosomal	884842	AA669359	2630858	NM_001001.1	4506650	NP_000992.1	4506651
	protein
	L36a
n300	ribosomal	949940	AA599178	2432803	NM_000990.2	1414118	NP_000981.1	4506625
	protein					9
	L27a
n301	HBS1 (S.	950926	AA608730	2457158
	cerevisiae)-
	like
n302	unnamed	1460257	AA883353	2992883
n303	H4 histone	1461138	AA868008	2963453	NM_003542.2	5579465	NP_003533.1	4504309
	family,
	member G
n304	unnamed	1623016	AI014781	3229117
n305	c-myc	417226	W87741	1401816	NM_002467	12962934	NP_002458.1	12962935
			W87861	1401926
n306	type I	135791	R33355	789213
	transmem-
	brane protein
	Fn14
n307	unnamed	1641528	AI005572	3215082
n308	Homo	28988	R40258	797874
	sapiens		R14308	767384
	cDNA
	FLJ12965
	fis, clone
	NT2RP2005
	741
n309	unnamed	34400	R24553	779441
			R44353	820649
n310	unnamed	50975	H17134	883374
			H17239	883479
n311	unnamed	108556	T69814	680962
n312	unnamed	156730	R73637	848007
			R73713	848083
n313	unnamed	197672	R93657	967823
			R94509	969904
n314	unnamed	211888	H66717	1025457
			H66718	1025458
n315	unnamed	213509	H71684	1043500
			H72247	1044063
n316	unnamed	271229	N34563	1155705
			N44560	1185654
n317	unnamed	273540	N36929	1158071
n318	unnamed	296452	N74625	1231910
			W00945	1272943
n319	src	470379	AA031284	1501239	NM_003149	4507246	NP_003140.1	4507247
	homology		AA031398	1501359
	three (SH3)
	and cysteine
	rich domain

[0064]

TABLE 2
Marker SEQ ID NO (nts)
n320   16
n321   17
n322   18
n323   19
n324   20
n325   21
n326   22
n327   23
n328   24
n329   25
n330   26
n331   27
n332   28
n333   29

[0065] Definitions

[0066] As used herein, each of the following terms has the meaning associated with it in this section.

[0067] The articles “a” and “an” are used herein to refer to one or to more than one (i.e. to at least one) of the grammatical object of the article. By way of example, “an element” means one element or more than one element.

[0068] A “marker” or “marker gene” is a gene whose altered level of expression in a tissue or cell from its expression level in normal or healthy tissue or cell is associated with a disease state, such as cancer. A marker gene may encode several different RNA transcripts, resulting from alternative splicing, processing or transcription initiation. A “marker nucleic acid” is a nucleic acid (e.g., RNA, DNA) comprising or corresponding to (in case of cDNA) the complete or a partial sequence of a RNA transcript encoded by a marker gene, or the complement of such complete or partial sequence. A “marker protein” is a protein encoded by or corresponding to a marker of the invention. The terms “protein” and “polypeptide” are used interchangeably.

[0069] The term “probe” refers to any molecule which is capable of selectively binding to a specifically intended target molecule, for example, a nucleotide transcript or protein encoded by or corresponding to a marker. Probes can be either synthesized by one skilled in the art, or derived from appropriate biological preparations. For purposes of detection of the target molecule, probes may be specifically designed to be labeled, as described herein. Examples of molecules that can be utilized as probes include, but are not limited to, RNA, DNA, proteins, antibodies, and organic molecules.

[0070] A “colon-associated” body fluid is a fluid which, when in the body of a patient, contacts or passes through colon cells or into which cells or proteins shed from colon cells are capable of passing. Exemplary colon-associated body fluids include blood fluids, stool, colon lavage fluids and lymph fluids.

[0071] The term “colon cancer” encompasses colon cancer and metastasized colon cancer. The latter may be located in organs other than the colon.

[0072] The “normal” level of expression of a marker is the level of expression of the marker in colon cells of a human subject or patient not afflicted with colon cancer

[0073] An “over-expression” or “significantly higher level of expression” of a marker refers to an expression level in a test sample that is greater than the standard error of the assay employed to assess expression, and is preferably at least twice, and more preferably three, four, five or ten times the expression level of the marker in a control sample (e.g., sample from a healthy subjects not having the marker associated disease) and preferably, the average expression level of the marker in several control samples.

[0074] A “significantly lower level of expression” of a marker refers to an expression level in a test sample that is at least twice, and more preferably three, four, five or ten times lower than the expression level of the marker in a control sample (e.g., sample from a healthy subject not having the marker associated disease) and preferably, the average expression level of the marker in several control samples.

[0075] As used herein, the term “promoter/regulatory sequence” means a nucleic acid sequence which is required for expression of a gene product operably linked to the promoter/regulatory sequence. In some instances, this sequence may be the core promoter sequence and in other instances, this sequence may also include an enhancer sequence and other regulatory elements which are required for expression of the gene product. The promoter/regulatory sequence may, for example, be one which expresses the gene product in a tissue-specific manner.

[0076] A “constitutive” promoter is a nucleotide sequence which, when operably linked with a polynucleotide which encodes or specifies a gene product, causes the gene product to be produced in a living human cell under most or all physiological conditions of the cell.

[0077] An “inducible” promoter is a nucleotide sequence which, when operably linked with a polynucleotide which encodes or specifies a gene product, causes the gene product to be produced in a living human cell substantially only when an inducer which corresponds to the promoter is present in the cell.

[0078] A “tissue-specific” promoter is a nucleotide sequence which, when operably linked with a polynucleotide which encodes or specifies a gene product, causes the gene product to be produced in a living human cell substantially only if the cell is a cell of the tissue type corresponding to the promoter.

[0079] A “transcribed polynucleotide” or “nucleotide transcript” is a polynucleotide (e.g. an mRNA, hnRNA, a cDNA, or an analog of such RNA or cDNA) which is identical to, complementary to or homologous with all or a portion of a RNA transcript encoded by a marker gene.

[0080] “Complementary” refers to the broad concept of sequence complementarity between regions of two nucleic acid strands or between two regions of the same nucleic acid strand. It is known that an adenine residue of a first nucleic acid region is capable of forming specific hydrogen bonds (“base pairing”) with a residue of a second nucleic acid region which is antiparallel to the first region if the residue is thymine or uracil. Similarly, it is known that a cytosine residue of a first nucleic acid strand is capable of base pairing with a residue of a second nucleic acid strand which is antiparallel to the first strand if the residue is guanine. A first region of a nucleic acid is complementary to a second region of the same or a different nucleic acid if, when the two regions are arranged in an antiparallel fashion, at least one nucleotide residue of the first region is capable of base pairing with a residue of the second region. Preferably, the first region comprises a first portion and the second region comprises a second portion, whereby, when the first and second portions are arranged in an antiparallel fashion, at least about 50%, and preferably at least about 75%, at least about 90%, or at least about 95% of the nucleotide residues of the first portion are capable of base pairing with nucleotide residues in the second portion. More preferably, all nucleotide residues of the first portion are capable of base pairing with nucleotide residues in the second portion.

[0081] “Homologous” as used herein, refers to nucleotide sequence similarity between two regions of the same nucleic acid strand or between regions of two different nucleic acid strands. When a nucleotide residue position in both regions is occupied by the same nucleotide residue, then the regions are homologous at that position. A first region is homologous to a second region if at least one nucleotide residue position of each region is occupied by the same residue. Homology between two regions is expressed in terms of the proportion of nucleotide residue positions of the two regions that are occupied by the same nucleotide residue. By way of example, a region having the nucleotide sequence 5′-ATTGCC-3′ and a region having the nucleotide sequence 5′-TATGGC-3′ share 50% homology. Preferably, the first region comprises a first portion and the second region comprises a second portion, whereby, at least about 50%, and preferably at least about 75%, at least about 90%, or at least about 95% of the nucleotide residue positions of each of the portions are occupied by the same nucleotide residue. More preferably, all nucleotide residue positions of each of the portions are occupied by the same nucleotide residue.

[0082] A molecule is “fixed” or “affixed” to a substrate if it is covalently or non-covalently associated with the substrate such the substrate can be rinsed with a fluid (e.g. standard saline citrate, pH 7.4) without a substantial fraction of the molecule dissociating from the substrate.

[0083] As used herein, a “naturally-occurring” nucleic acid molecule refers to an RNA or DNA molecule having a nucleotide sequence that occurs in an organism found in nature.

[0084] A cancer is “inhibited” if at least one symptom of the cancer is alleviated, terminated, slowed, or prevented. As used herein, colon cancer is also “inhibited” if recurrence or metastasis of the cancer is reduced, slowed, delayed, or prevented.

[0085] A kit is any manufacture (e.g. a package or container) comprising at least one reagent, e.g. a probe, for specifically detecting the expression of a marker of the invention. The kit may be promoted, distributed, or sold as a unit for performing the methods of the present invention.

[0086] “Proteins of the invention” encompass marker proteins and their fragments; variant marker proteins and their fragments; peptides and polypeptides comprising an at least 15 amino acid segment of a marker or variant marker protein; and fusion proteins comprising a marker or variant marker protein, or an at least 15 amino acid segment of a marker or variant marker protein.

[0087] Unless otherwise specified herewithin, the terms “antibody” and “antibodies” broadly encompass naturally-occurring forms of antibodies (e.g., IgG, IgA, IgM, IgE) and recombinant antibodies such as single-chain antibodies, chimeric and humanized antibodies and multi-specific antibodies, as well as fragments and derivatives of all of the foregoing, which fragments and derivatives have at least an antigenic binding site. Antibody derivatives may comprise a protein or chemical moiety conjugated to an antibody.

[0088] Description

[0089] The present invention is based, in part, on newly identified markers which are over-expressed in metastasized colon cancer cells as compared to their expression in normal (i.e. non-cancerous) colon and normal liver cells. The enhanced expression of one or more of these markers in a patient sample indicates the patient has or is likely to develop colon cancer, particularly metastasized colon cancer. e. The invention provides compositions, kits, and methods for assessing the cancerous state of colon cells (e.g. cells obtained from a human, cultured human cells, archived or preserved human cells and in vivo cells) as well as treating patients afflicted with colon cancer, particularly metastasized colon cancer.

[0090] The compositions, kits, and methods of the invention have the following uses, among others:

[0091] 1) assessing whether a patient is afflicted with colon cancer;

[0092] 2) assessing the stage of colon cancer in a human patient;

[0093] 3) assessing the grade of colon cancer in a patient;

[0094] 4) assessing the benign or malignant nature of colon cancer in a patient;

[0095] 5) assessing the presence of adenomatous polyps;

[0096] 6) assessing the presence of colon adenocarcinomas;

[0097] 7) assessing the metastatic potential of colon cancer in a patient;

[0098] 8) assessing the histological type of neoplasm associated with colon cancer in a patient;

[0099] 9) making antibodies, antibody fragments or antibody derivatives that are useful for treating colon cancer and/or assessing whether a patient is afflicted with colon cancer;

[0100] 10) assessing the presence of colon cancer cells;

[0101] 11) assessing the efficacy of one or more test compounds for inhibiting colon cancer in a patient;

[0102] 12) assessing the efficacy of a therapy for inhibiting colon cancer in a patient;

[0103] 13) monitoring the progression of colon cancer in a patient;

[0104] 14) selecting a composition or therapy for inhibiting colon cancer in a patient;

[0105] 15) treating a patient afflicted with colon cancer;

[0106] 16) detecting early onset colon cancer;

[0107] 17) detecting colon cancer in young patients;

[0108] 18) inhibiting colon cancer in a patient;

[0109] 19) assessing the colon carcinogenic potential of a test compound; and

[0110] 20) preventing the onset of colon cancer in a patient at risk for developing colon cancer.

[0111] The invention thus includes a method of assessing whether a patient is afflicted with colon cancer, particularly metastasized colon cancer. This method comprises comparing the level of expression of a marker of the invention (listed in Tables 1 and 2) in a patient sample and the normal level of expression of the marker in a control, e.g., a non-colon cancer sample. A significantly higher level of expression of the marker in the patient sample as compared to the normal level is an indication that the patient is afflicted with colon cancer, particularly metastasized colon cancer.

[0112] Any marker gene or combination of marker genes listed within Tables 1 and 2, as well as any known colon cancer marker genes in combination with the marker genes set forth within Tables 1 and 2, may be used in the compositions, kits, and methods of the present invention. In general, it is preferable to use marker genes for which the difference between the level of expression of the marker gene in colon cancer cells or colon-or liver-associated body fluids and the level of expression of the same marker gene in normal colon or liver cells or colon- or liver-associated body fluids is as great as possible. Although this difference can be as small as the limit of detection of the method for assessing expression of the marker gene, it is preferred that the difference be at least greater than the standard error of the assessment method, and preferably a difference of at least 2-, 3-, 4-, 5-, 6-, 7-, 8-, 9-, 10-, 15-, 20-, 25-, 100-, 500-, 1000-fold or greater.

[0113] It will be appreciated that patient samples containing colon cells or colon cancer cells may be used in the methods of the present invention. In these embodiments, the level of expression of the marker gene can be assessed by assessing the amount (e.g. absolute amount or concentration) of a marker gene product (e.g., protein and RNA transcript encoded by the marker gene and fragments of the protein and RNA transcript) in a sample, e.g., stool and/or blood obtained from a patient. The sample can, of course, be subjected to a variety of well-known post-collection preparative and storage techniques (e.g. fixation, storage, freezing, lysis, homogenization, DNA or RNA extraction, ultrafiltration, concentration, evaporation, centrifugation, etc.) prior to assessing the amount of the marker gene product in the sample.

[0114] Preferred in vivo techniques for detection of a protein encoded by a marker gene of the invention include introducing into a subject an antibody that specifically binds the protein, or a polypeptide or protein fragment comprising the protein. In certain embodiments, the antibody can be labeled with a radioactive molecule whose presence and location in a subject can be detected by standard imaging techniques.

[0115] Expression of a marker gene of the invention may be assessed by any of a wide variety of well known methods for detecting expression of a transcribed nucleotide or encoded protein. Non-limiting examples of such methods include immunological methods for detection of secreted, cell-surface, cytoplasmic, or nuclear proteins, protein purification methods, protein function or activity assays, nucleic acid hybridization methods, nucleic acid reverse transcription methods, and nucleic acid amplification methods. Such method may also include physical methods such as liquid and gas chromatography, mass spectroscopy, and nuclear magnetic resonance.

[0116] In a preferred embodiment, expression of a marker gene is assessed using an antibody (e.g. a radio-labeled, chromophore-labeled, fluorophore-labeled, or enzyme-labeled antibody), an antibody derivative (e.g. an antibody conjugated with a substrate or with the protein or ligand of a protein-ligand pair {e.g. biotin-streptavidin}), or an antibody fragment (e.g. a single-chain antibody, an isolated antibody hypervariable domain, etc.) which binds specifically with a protein encoded by the marker gene or a polypeptide or a protein fragment comprising the protein, wherein the protein may have undergone none, all or a portion of its normal post-translational modification and/or proteolysis during the course of its secretion or release from colon cells, cancerous or otherwise.

[0117] In another preferred embodiment, expression of a marker gene is assessed by preparing mRNA/cDNA (i.e. a transcribed polynucleotide) from cells in a patient sample, and by hybridizing the mRNA/cDNA with a reference polynucleotide which comprises the marker gene sequence or its complement, or a fragment of said sequence or complement. cDNA can, optionally, be amplified using any of a variety of polymerase chain reaction methods prior to hybridization with the reference polynucleotide. Expression of one or more marker genes can likewise be detected using quantitative PCR to assess the level of RNA transcripts encoded by the marker gene(s).

[0118] In a related embodiment, a mixture of transcribed polynucleotides obtained from the sample is contacted with a substrate having fixed thereto a polynucleotide complementary to or homologous with at least a portion (e.g. at least 7, 10, 15, 20, 25, 30, 40, 50, 100, 500, or more nucleotide residues) of a RNA transcript encoded by a marker gene of the invention. If polynucleotides complementary to or homologous with a RNA transcript encoded by the marker gene of the invention are differentially detectable on the substrate (e.g. detectable using radioactivity, different chromophores or fluorophores), are fixed to different selected positions, then the levels of expression of a plurality of marker genes can be assessed simultaneously using a single substrate (e.g. a “gene chip” microarray of polynucleotides fixed at selected positions). When a method of assessing marker gene expression is used which involves hybridization of one nucleic acid with another, it is preferred that the hybridization be performed under stringent hybridization conditions.

[0119] Because the compositions, kits, and methods of the invention rely on detection of a difference in expression levels of one or more marker genes of the invention, it is preferable that the level of expression of the marker gene is significantly greater than the minimum detection limit of the method used to assess expression in at least one of normal colon cells, normal liver cells and cancerous colon cells.

[0120] It is understood that by routine screening of additional patient samples for the expression levels of one or more of the marker genes of the invention, it will be realized that certain of the marker genes are over-expressed in cancers of various types, including specific colon cancers, as well as other cancers such as breast, cervical, prostate, lung or ovarian cancers. For example, it will be confirmed that some of the marker genes of the invention are over-expressed in most (i.e. 50% or more) or substantially all (i.e. 80% or more) of colon cancer. Furthermore, it will be confirmed that certain of the marker genes of the invention are associated with colon cancer of various stages.

[0121] All cancers have staging schemes that are used to describe the degree to which the cancer has progressed. A generally accepted scoring system, known as the TNM staging system, has been established by the American Joint Committee on Cancer (AJCC). The TNM system approach assigns the primary tumor to one of four stages (Tis, T0, T1, T2, T3, T4) based on the size and location of the primary tumor within the colon or rectum. The regional lymph node stage (N0, N1, N2, or N3) and level of distant metastases (M0 or M1) are indicated with each score as well. For example, colon Tis (in situ) cancer designates a tumor in its early polyp stage which has not grown beyond the inner lining of the mucosa. A T1 designation indicates a tumor which is 2 cm or less in its greatest dimension. Generally, a T1 colorectal tumor is at a stage where it has invaded the submucosa, but not the muscularis propria. A T1N1 designation refers to the same stage of tumor with 1-3 regional lymph node metastases. A T2 colorectal tumor is greater than 2 cm but not greater than 5 cm in its greatest dimension. Generally, a T2 colorectal tumor is at a stage where it has penetrated into, but not through, the muscularis propria. In all forms of stage T3 disease the tumors have extended through the wall of the colon into surrounding tissue. The T4 designation refers to tumors that have escaped from the colon and can be found in distant regions. A description of the TNM system of colon cancer classification can be found in AJCC Cancer Staging Manual, Fifth Ed., Lippincott, Williams & Wilkins (1997) (ISBN: 0-397-58414-8).

[0122] It will thus be appreciated that as a greater number of patient samples are assessed for expression of the marker genes of the invention and the outcomes of the individual patients from whom the samples were obtained are correlated, it will also be confirmed that altered expression of certain of the marker genes of the invention are strongly correlated with malignant cancers and that altered expression of other marker genes of the invention are strongly correlated with benign tumors. The compositions, kits, and methods of the invention are thus useful for characterizing one or more of the stage, grade, histological type, metastatic potential, indolent vs. aggressive phenotype and benign/malignant nature of colon cancer in patients.

[0123] When the compositions, kits, and methods of the invention are used for characterizing one or more of the stage, grade, histological type, metastatic potential, indolent vs. aggressive phenotype and benign/malignant nature of colon cancer in a patient, it is preferred that the marker gene or panel of marker genes of the invention, whose expression level is assessed, is selected such that a positive result is obtained in at least about 20%, and preferably at least about 40%, 60%, or 80%, and more preferably in substantially all patients afflicted with a colon cancer of the corresponding stage, grade, histological type, metastatic potential, indolent vs. aggressive phenotype or benign/malignant nature. Preferably, the marker gene or panel of marker genes of the invention is selected such that a positive predictive value (PPV) of greater than about 10% is obtained for the general population.

[0124] When a plurality of marker genes of the invention are used in the methods of the invention, the level of expression of each marker gene in a patient sample can be compared with the normal level of expression of each of the plurality of marker genes in non-cancerous samples of the same type, either in a single reaction mixture (i.e. using reagents, such as different fluorescent probes, for each marker gene or a mixture of similarly labeled probes to access expression level of a plurality of marker genes whose probes are fixed to a single substrate at different positions) or in individual reaction mixtures corresponding to one or more of the marker genes. In one embodiment, a significantly enhanced level of expression of more than one of the plurality of marker genes in the sample, relative to the corresponding normal levels, is an indication that the patient is afflicted with colon cancer. When the expression level of a plurality of marker genes is assessed, it is preferred that the expression level of 2, 3, 4, 5, 8, 10, 12, 15, 20, 30, or 40 or more individual marker genes is assessed.

[0125] In order to maximize the sensitivity of the compositions, kits, and methods of the invention (i.e. by interference attributable to cells of non-colon origin in a patient sample), it is preferable that the marker gene of the invention whose expression level is examined therein be a marker gene which is tissue specific, e.g., normally not expressed in non-colon tissue.

[0126] There are only a small number of marker genes whose expression are known to be associated with colon cancers (for example, c-met, L7a, APC; see Wang et al, (2000) Int. J. Oncol. 16:757-762, Nishisho et al, (1991) Science 253:665-669, Umeki et al, (1999) Oncology 56:314-321). These marker genes are not, of course, included among the marker genes of the invention, although they may be used together with one or more marker genes of the invention in a panel of marker genes, for example. It is well known that certain types of genes, such as oncogenes, tumor suppressor genes, growth factor-like genes, protease-like genes, and protein kinase-like genes are often involved with development of cancers of various types. Thus, among the marker genes of the invention, use of those which encode proteins which resemble known secreted proteins such as growth factors, proteases and protease inhibitors are preferred.

[0127] Known growth factors include platelet-derived growth factor alpha, platelet-derived growth factor beta (simian sarcoma viral {v-sis) oncogene homolog), thrombopoietin (myeloproliferative leukemia virus oncogene ligand, megakaryocyte growth and development factor), erythropoietin, B cell growth factor, macrophage stimulating factor 1 (hepatocyte growth factor-like protein), hepatocyte growth factor (hepapoietin A), insulin-like growth factor 1 (somatomedia C), hepatoma-derived growth factor, amphiregulin (schwannoma-derived growth factor), bone morphogenetic proteins 1, 2, 3, 3 beta, and 4, bone morphogenetic protein 7 (osteogenic protein 1), bone morphogenetic protein 8 (osteogenic protein 2), connective tissue growth factor, connective tissue activation peptide 3, epidermal growth factor (EGF), teratocarcinoma-derived growth factor 1, endothelin, endothelin 2, endothelin 3, stromal cell-derived factor 1, vascular endothelial growth factor (VEGF), VEGF-B, VEGF-C, placental growth factor (vascular endothelial growth factor-related protein), transforming growth factor alpha, transforming growth factor beta 1 and its precursors, transforming growth factor beta 2 and its precursors, fibroblast growth factor 1 (acidic), fibroblast growth factor 2 (basic), fibroblast growth factor 5 and its precursors, fibroblast growth factor 6 and its precursors, fibroblast growth factor 7 (keratinocyte growth factor), fibroblast growth factor 8 (androgen-induced), fibroblast growth factor 9 (glia-activating factor), pleiotrophin (heparin binding growth factor 8, neurite growth-promoting factor 1), brain-derived neurotrophic factor, and recombinant glial growth factor 2.

[0128] Known proteases include interleukin-1 beta convertase and its precursors, Mch6 and its precursors, Mch2 isoform alpha, Mch4, Cpp32 isoform alpha, Lice2 gamma cysteine protease, Ich-1 S, Ich-1 L, Ich-2 and its precursors, TY protease, matrix metalloproteinase 1 (interstitial collagenase), matrix metalloproteinase 2 (gelatinase A, 72 kD gelatinase, 72 kD type IV collagenase), matrix metalloproteinase 7 (matrilysin), matrix metalloproteinase 8 (neutrophil collagenase), matrix metalloproteinase 12 (macrophage elastase), matrix metalloproteinase 13 (collagenase 3), metallopeptidase 1, cysteine-rich metalloprotease (disintegrin) and its precursors, subtilisin-like protease Pc8 and its precursors, chymotrypsin, snake venom-like protease, cathepsin 1, cathepsin D (lysosomal aspartyl protease), stromelysin, aminopeptidase N, plasminogen, tissue plasminogen activator, plasminogen activator inhibitor type II, and urokinase-type plasminogen activator.

[0129] Gene delivery vehicles, host cells and compositions (all described herein) containing nucleic acids comprising the entirety, or a segment of 15 or more nucleotides, of any of the nucleotide sequences of the markers. or the complement of such sequences, and polypeptides comprising the entirety, or a segment of 10 or more amino acids, of any of protein sequences of the markers are also provided by this invention.

[0130] As described herein, colon cancer, particularly metastasized colon cancer, in patients is associated with an increased level of expression of one or more markers of the invention. While, as discussed above, some of these changes in expression level result from occurrence of the colon cancer, others of these changes induce, maintain, and promote the cancerous state of colon cancer cells. Thus, colon cancer characterized by an increase in the level of expression of one or more markers of the invention can be inhibited by reducing and/or interfering with the expression of the markers and/or function of the proteins encoded by those markers.

[0131] Expression of a marker of the invention can be inhibited in a number of ways generally known in the art. For example, an antisense oligonucleotide can be provided to the colon cancer cells in order to inhibit transcription, translation, or both, of the marker(s). Alternately, a polynucleotide encoding an antibody, an antibody derivative, or an antibody fragment which specifically binds a marker protein, and operably linked with an appropriate promoter/regulator region, can be provided to the cell in order to generate intracellular antibodies which will inhibit the function or activity of the protein. The expression and/or function of a marker may also be inhibited by treating the colon cancer cell with an antibody, antibody derivative or antibody fragment that specifically binds a marker protein. Using the methods described herein, a variety of molecules, particularly including molecules sufficiently small that they are able to cross the cell membrane, can be screened in order to identify molecules which inhibit expression of a marker or inhibit the function of a marker protein. The compound so identified can be provided to the patient in order to inhibit colon cancer cells of the patient.

[0132] Any marker or combination of markers of the invention, as well as any known markers in combination with the markers of the invention, may be used in the compositions, kits, and methods of the present invention. In general, it is preferable to use markers for which the difference between the level of expression of the marker in colon cancer cells and the level of expression of the same marker in normal colon cells or normal liver cells is as great as possible. Although this difference can be as small as the limit of detection of the method for assessing expression of the marker, it is preferred that the difference be at least greater than the standard error of the assessment method, and preferably a difference of at least 2-, 3-, 4-, 5-, 6-, 7-, 8-, 9-, 10-, 15-, 20-, 25-, 100-, 500-, 1000-fold or greater than the level of expression of the same marker in normal colon or normal liver tissue.

[0133] It is recognized that certain marker proteins are secreted from colon cancer cells (i.e., one or both of normal and cancerous cells) to the extracellular space surrounding the cells. These markers are preferably used in certain embodiments of the compositions, kits, and methods of the invention, owing to the fact that the such marker proteins can be detected in a colon-associated body fluid sample, which may be more easily collected from a human patient than a tissue biopsy sample. In addition, preferred in vivo techniques for detection of a marker protein include introducing into a subject a labeled antibody directed against the protein. For example, the antibody can be labeled with a radioactive marker whose presence and location in a subject can be detected by standard imaging techniques.

[0134] It is a simple matter for the skilled artisan to determine whether any particular marker protein is a secreted protein. In order to make this determination, the marker protein is expressed in, for example, a mammalian cell, preferably a human colon cell line, extracellular fluid is collected, and the presence or absence of the protein in the extracellular fluid is assessed (e.g. using a labeled antibody which binds specifically with the protein).

[0135] The following is an example of a method which can be used to detect secretion of a protein. About 8×105 293T cells are incubated at 37° C. in wells containing growth medium (Dulbecco's modified Eagle's medium {DMEM} supplemented with 10% fetal bovine serum) under a 5% (v/v) CO2, 95% air atmosphere to about 60-70% confluence. The cells are then transfected using a standard transfection mixture comprising 2 micrograms of DNA comprising an expression vector encoding the protein and 10 microliters of LipofectAMINE™ (GIBCO/BRL Catalog no. 18342-012) per well. The transfection mixture is maintained for about 5 hours, and then replaced with fresh growth medium and maintained in an air atmosphere. Each well is gently rinsed twice with DMEM which does not contain methionine or cysteine (DMEM-MC; ICN Catalog no. 16-424-54). About 1 milliliter of DMEM-MC and about 50 microcuries of Trans- 35S™ reagent (ICN Catalog no. 51006) are added to each well. The wells are maintained under the 5% CO2 atmosphere described above and incubated at 37° C. for a selected period. Following incubation, 150 microliters of conditioned medium is removed and centrifuged to remove floating cells and debris. The presence of the protein in the supernatant is an indication that the protein is secreted.

[0136] It will be appreciated that patient samples containing colon cells or colon cancer cells may be used in the methods of the present invention. In these embodiments, the level of expression of the marker can be assessed by assessing the amount (e.g. absolute amount or concentration) of the marker in a colon cell sample, e.g., colon smear obtained from a patient. The cell sample can, of course, be subjected to a variety of well-known post-collection preparative and storage techniques (e.g. nucleic acid and/or protein extraction, fixation, storage, freezing, ultrafiltration, concentration, evaporation, centrifugation, etc.) prior to assessing the amount of the marker in the sample. Likewise, colon smears may also be subjected to post-collection preparative and storage techniques, e.g., fixation.

[0137] The compositions, kits, and methods of the invention can be used to detect expression of marker proteins having at least one portion which is displayed on the surface of cells which express it. It is a simple matter for the skilled artisan to determine whether a marker protein, or a portion thereof, is exposed on the cell surface. For example, immunological methods may be used to detect such proteins on whole cells, or well known computer-based sequence analysis methods (e.g. the SIGNALP program; Nielsen et al., 1997, Protein Engineering 10:1-6) may be used to predict the presence of at least one extracellular domain (i.e. including both secreted proteins and proteins having at least one cell-surface domain). Expression of a marker protein having at least one portion which is displayed on the surface of a cell which expresses it may be detected without necessarily lysing the cell (e.g. using a labeled antibody which binds specifically with a cell-surface domain of the protein).

[0138] It is recognized that the compositions, kits, and methods of the invention will be of particular utility to patients having an enhanced risk of developing colon cancer and their medical advisors. Patients recognized as having an enhanced risk of developing colon cancer include, for example, patients having a familial history of colon cancer and patients identified as having a mutant oncogene (i.e. at least one allele). Certain markers listed in Tables 1 and 2 have particular utility in detecting certain types of colon cancer. For example, markers n1-n84 and n305-n307 are particularly useful for detecting metastatic colon cancer. Whereas markers n85-n304 and n308-n319 are useful for detecting both primary as well as metastatic colon cancer. Markers n320-n333 listed in Table 2 are useful for detecting colon tumors and particularly useful for detecting metastatic colon tumors and primary colon tumors that are likely to metastasize.

[0139] The level of expression of a marker in normal (i.e. non-cancerous) human colon or liver tissue can be assessed in a variety of ways. In one embodiment, this normal level of expression is assessed by assessing the level of expression of the marker in a portion of colon cells which appears to be non-cancerous and by comparing this normal level of expression with the level of expression in a portion of the colon cells which is suspected of being cancerous. Alternately, and particularly as further information becomes available as a result of routine performance of the methods described herein, population-average values for normal expression of the markers of the invention may be used. In other embodiments, the ‘normal’ level of expression of a marker may be determined by assessing expression of the marker in a patient sample obtained from a non-cancer-afflicted patient, from a patient sample obtained from a patient before the suspected onset of colon cancer in the patient, from archived patient samples, and the like.

[0140] The invention includes compositions, kits, and methods for assessing the presence of colon cancer cells in a sample (e.g. an archived tissue sample or a sample obtained from a patient). These compositions, kits, and methods are substantially the same as those described above, except that, where necessary, the compositions, kits, and methods are adapted for use with samples other than patient samples. For example, when the sample to be used is a parafinized, archived human tissue sample, it can be necessary to adjust the ratio of compounds in the compositions of the invention, in the kits of the invention, or the methods used to assess levels of marker expression in the sample. Such methods are well known in the art and within the skill of the ordinary artisan.

[0141] The invention includes a kit for assessing the presence of colon cancer cells (e.g. in a sample such as a patient sample). The kit comprises a plurality of reagents, each of which is capable of binding specifically with a marker nucleic acid or protein. Suitable reagents for binding with a marker protein include antibodies, antibody derivatives, antibody fragments, and the like. Suitable reagents for binding with a marker nucleic acid (e.g. a genomic DNA, an mRNA, a spliced mRNA, a cDNA, or the like) include complementary nucleic acids. For example, the nucleic acid reagents may include oligonucleotides (labeled or non-labeled) fixed to a substrate, labeled oligonucleotides not bound with a substrate, pairs of PCR primers, molecular beacon probes, and the like.

[0142] The kit of the invention may optionally comprise additional components useful for performing the methods of the invention. By way of example, the kit may comprise fluids (e.g. SSC buffer) suitable for annealing complementary nucleic acids or for binding an antibody with a protein with which it specifically binds, one or more sample compartments, an instructional material which describes performance of a method of the invention, a sample of normal colon cells, a sample of normal liver cells, a sample of colon cancer cells, and the like.

[0143] The invention also includes a method of making an isolated hybridoma which produces an antibody useful for assessing whether patient is afflicted with an colon cancer. In this method, a protein or peptide comprising the entirety or a segment of a marker protein is synthesized or isolated (e.g. by purification from a cell in which it is expressed or by transcription and translation of a nucleic acid encoding the protein or peptide in vivo or in vitro using known methods). A vertebrate, preferably a mammal such as a mouse, rat, rabbit, or sheep, is immunized using the protein or peptide. The vertebrate may optionally (and preferably) be immunized at least one additional time with the protein or peptide, so that the vertebrate exhibits a robust immune response to the protein or peptide. Splenocytes are isolated from the immunized vertebrate and fused with an immortalized cell line to form hybridomas, using any of a variety of methods well known in the art. Hybridomas formed in this manner are then screened using standard methods to identify one or more hybridomas which produce an antibody which specifically binds with the marker protein or a fragment thereof. The invention also includes hybridomas made by this method and antibodies made using such hybridomas.

[0144] The invention also includes a method of assessing the efficacy of a test compound for inhibiting colon cancer cells. As described above, differences in the level of expression of the markers of the invention correlate with the cancerous state of colon cells. Although it is recognized that changes in the levels of expression of certain of the markers of the invention likely result from the cancerous state of colon cells, it is likewise recognized that changes in the levels of expression of other of the markers of the invention induce, maintain, and promote the cancerous state of those cells. Thus, compounds which inhibit an colon cancer in a patient will cause the level of expression of one or more of the markers of the invention to change to a level nearer the normal level of expression for that marker (i.e. the level of expression for the marker in non-cancerous colon cells).

[0145] This method thus comprises comparing expression of a marker in a first colon cell sample and maintained in the presence of the test compound and expression of the marker in a second colon cell sample and maintained in the absence of the test compound. A significantly reduced expression of a marker of the invention in the presence of the test compound is an indication that the test compound inhibits colon cancer. The colon cell samples may, for example, be aliquots of a single sample of normal colon cells obtained from a patient, pooled samples of normal colon cells obtained from a patient, cells of a normal colon cell line, aliquots of a single sample of colon cancer cells obtained from a patient, pooled samples of colon cancer cells obtained from a patient, cells of an colon cancer cell line, or the like. In one embodiment, the samples are colon cancer cells obtained from a patient and a plurality of compounds known to be effective for inhibiting various colon cancers are tested in order to identify the compound which is likely to best inhibit the colon cancer in the patient.

[0146] This method may likewise be used to assess the efficacy of a therapy for inhibiting colon cancer in a patient. In this method, the level of expression of one or more markers of the invention in a pair of samples (one subjected to the therapy, the other not subjected to the therapy) is assessed. As with the method of assessing the efficacy of test compounds, if the therapy induces a significantly lower level of expression of a marker of the invention then the therapy is efficacious for inhibiting colon cancer. As above, if samples from a selected patient are used in this method, then alternative therapies can be assessed in vitro in order to select a therapy most likely to be efficacious for inhibiting colon cancer in the patient.

[0147] As described above, the cancerous state of human colon cells is correlated with changes in the levels of expression of the markers of the invention. The invention includes a method for assessing the human colon cell carcinogenic potential of a test compound. This method comprises maintaining separate aliquots of human colon cells in the presence and absence of the test compound. Expression of a marker of the invention in each of the aliquots is compared. A significantly higher level of expression of a marker of the invention in the aliquot maintained in the presence of the test compound (relative to the aliquot maintained in the absence of the test compound) is an indication that the test compound possesses human colon cell carcinogenic potential. The relative carcinogenic potentials of various test compounds can be assessed by comparing the degree of enhancement or inhibition of the level of expression of the relevant markers, by comparing the number of markers for which the level of expression is enhanced or inhibited, or by comparing both.

[0148] Various aspects of the invention are described in further detail in the following subsections.

[0149] I. Isolated Nucleic Acid Molecules

[0150] One aspect of the invention pertains to isolated nucleic acid molecules, including nucleic acids which encode a marker protein or a portion thereof. Isolated nucleic acids of the invention also include nucleic acid molecules sufficient for use as hybridization probes to identify marker nucleic acid molecules, and fragments of marker nucleic acid molecules, e.g., those suitable for use as PCR primers for the amplification or mutation of marker nucleic acid molecules. As used herein, the term “nucleic acid molecule” is intended to include DNA molecules (e.g., cDNA or genomic DNA) and RNA molecules (e.g., mRNA) and analogs of the DNA or RNA generated using nucleotide analogs. The nucleic acid molecule can be single-stranded or double-stranded, but preferably is double-stranded DNA.

[0151] An “isolated” nucleic acid molecule is one which is separated from other nucleic acid molecules which are present in the natural source of the nucleic acid molecule. Preferably, an “isolated” nucleic acid molecule is free of sequences (preferably protein-encoding sequences) which naturally flank the nucleic acid (i.e., sequences located at the 5′ and 3′ ends of the nucleic acid) in the genomic DNA of the organism from which the nucleic acid is derived. For example, in various embodiments, the isolated nucleic acid molecule can contain less than about 5 kB, 4 kB, 3 kB, 2 kB, 1 kB, 0.5 kB or 0.1 kB of nuc-leotide sequences which naturally flank the nucleic acid molecule in genomic DNA of the cell from which the nucleic acid is derived. Moreover, an “isolated” nucleic acid molecule, such as a cDNA molecule, can be substantially free of other cellular material, or culture medium when produced by recombinant techniques, or substantially free of chemical precursors or other chemicals when chemically synthesized.

[0152] A nucleic acid molecule of the present invention can be isolated using standard molecular biology techniques and the sequence information in the database records described herein. Using all or a portion of such nucleic acid sequences, nucleic acid molecules of the invention can be isolated using standard hybridization and cloning techniques (e.g., as described in Sambrook et al., ed., Molecular Cloning: A Laboratory Manual, 2nd ed., Cold Spring Harbor Laboratory Press, Cold Spring Harbor, N.Y., 1989).

[0153] A nucleic acid molecule of the invention can be amplified using cDNA, mRNA, or genomic DNA as a template and appropriate oligonucleotide primers according to standard PCR amplification techniques. The nucleic acid so amplified can be cloned into an appropriate vector and characterized by DNA sequence analysis. Furthermore, nucleotides corresponding to all or a portion of a nucleic acid molecule of the invention can be prepared by standard synthetic techniques, e.g., using an automated DNA synthesizer.

[0154] In another preferred embodiment, an isolated nucleic acid molecule of the invention comprises a nucleic acid molecule which has a nucleotide sequence complementary to the nucleotide sequence of a marker nucleic acid or to the nucleotide sequence of a nucleic acid encoding a marker protein. A nucleic acid molecule which is complementary to a given nucleotide sequence is one which is sufficiently complementary to the given nucleotide sequence that it can hybridize to the given nucleotide sequence thereby forming a stable duplex.

[0155] Moreover, a nucleic acid molecule of the invention can comprise only a portion of a nucleic acid sequence, wherein the full length nucleic acid sequence comprises a marker nucleic acid or which encodes a marker protein. Such nucleic acids can be used, for example, as a probe or primer. The probe/primer typically is used as one or more substantially purified oligonucleotides. The oligonucleotide typically comprises a region of nucleotide sequence that hybridizes under stringent conditions to at least about 7, preferably about 15, more preferably about 25, 50, 75, 100, 125, 150, 175, 200, 250, 300, 350, or 400 or more consecutive nucleotides of a nucleic acid of the invention.

[0156] Probes based on the sequence of a nucleic acid molecule of the invention can be used to detect transcripts or genomic sequences corresponding to one or more markers of the invention. The probe comprises a label group attached thereto, e.g., a radioisotope, a fluorescent compound, an enzyme, or an enzyme co-factor. Such probes can be used as part of a diagnostic test kit for identifying cells or tissues which mis-express the protein, such as by measuring levels of a nucleic acid molecule encoding the protein in a sample of cells from a subject, e.g., detecting mRNA levels or determining whether a gene encoding the protein has been mutated or deleted.

[0157] The invention further encompasses nucleic acid molecules that differ, due to degeneracy of the genetic code, from the nucleotide sequence of nucleic acids encoding a marker protein and thus encode the same protein.

[0158] It will be appreciated by those skilled in the art that DNA sequence polymorphisms that lead to changes in the amino acid sequence can exist within a population (e.g., the human population). Such genetic polymorphisms can exist among individuals within a population due to natural allelic variation. An allele is one of a group of genes which occur alternatively at a given genetic locus. In addition, it will be appreciated that DNA polymorphisms that affect RNA expression levels can also exist that may affect the overall expression level of that gene (e.g., by affecting regulation or degradation).

[0159] As used herein, the phrase “allelic variant” refers to a nucleotide sequence which occurs at a given locus or to a polypeptide encoded by the nucleotide sequence.

[0160] As used herein, the terms “gene” and “recombinant gene” refer to nucleic acid molecules comprising an open reading frame encoding a polypeptide corresponding to a marker of the invention. Such natural allelic variations can typically result in 1-5% variance in the nucleotide sequence of a given gene. Alternative alleles can be identified by sequencing the gene of interest in a number of different individuals. This can be readily carried out by using hybridization probes to identify the same genetic locus in a variety of individuals. Any and all such nucleotide variations and resulting amino acid polymorphisms or variations that are the result of natural allelic variation and that do not alter the functional activity are intended to be within the scope of the invention.

[0161] In another embodiment, an isolated nucleic acid molecule of the invention is at least 7, 15, 20, 25, 30, 40, 60, 80, 100, 150, 200, 250, 300, 350, 400, 450, 550, 650, 700, 800, 900, 1000, 1200, 1400, 1600, 1800, 2000, 2200, 2400, 2600, 2800, 3000, 3500, 4000, 4500, or more nucleotides in length and hybridizes under stringent conditions to a marker nucleic acid or to a nucleic acid encoding a marker protein. As used herein, the term “hybridizes under stringent conditions” is intended to describe conditions for hybridization and washing under which nucleotide sequences at least 60% (65%, 70%, preferably 75%) identical to each other typically remain hybridized to each other. Such stringent conditions are known to those skilled in the art and can be found in sections 6.3.1-6.3.6 of Current Protocols in Molecular Biology, John Wiley & Sons, N.Y. (1989). A preferred, non-limiting example of stringent hybridization conditions are hybridization in 6×sodium chloride/sodium citrate (SSC) at about 45° C., followed by one or more washes in 0.2×SSC, 0.1% SDS at 50-65° C.

[0162] In addition to naturally-occurring allelic variants of a nucleic acid molecule of the invention that can exist in the population, the skilled artisan will further appreciate that sequence changes can be introduced by mutation thereby leading to changes in the amino acid sequence of the encoded protein, without altering the biological activity of the protein encoded thereby. For example, one can make nucleotide substitutions leading to amino acid substitutions at “non-essential” amino acid residues. A “non-essential” amino acid residue is a residue that can be altered from the wild-type sequence without altering the biological activity, whereas an “essential” amino acid residue is required for biological activity. For example, amino acid residues that are not conserved or only semi-conserved among homologs of various species may be non-essential for activity and thus would be likely targets for alteration. Alternatively, amino acid residues that are conserved among the homologs of various species (e.g., murine and human) may be essential for activity and thus would not be likely targets for alteration.

[0163] Accordingly, another aspect of the invention pertains to nucleic acid molecules encoding a variant marker protein that contain changes in amino acid residues that are not essential for activity. Such variant marker proteins differ in amino acid sequence from the naturally-occurring marker proteins, yet retain biological activity. In one embodiment, such a variant marker protein has an amino acid sequence that is at least about 40% identical, 50%, 60%, 70%, 80%, 90%, 95%, or 98% identical to the amino acid sequence of a marker protein.

[0164] An isolated nucleic acid molecule encoding a variant marker protein can be created by introducing one or more nucleotide substitutions, additions or deletions into the nucleotide sequence of marker nucleic acids, such that one or more amino acid residue substitutions, additions, or deletions are introduced into the encoded protein. Mutations can be introduced by standard techniques, such as site-directed mutagenesis and PCR-mediated mutagenesis. Preferably, conservative amino acid substitutions are made at one or more predicted non-essential amino acid residues. A “conservative amino acid substitution” is one in which the amino acid residue is replaced with an amino acid residue having a similar side chain. Families of amino acid residues having similar side chains have been defined in the art. These families include amino acids with basic side chains (e.g., lysine, arginine, histidine), acidic side chains (e.g., aspartic acid, glutamic acid), uncharged polar side chains (e.g., glycine, asparagine, glutamine, serine, threonine, tyrosine, cysteine), non-polar side chains (e.g., alanine, valine, leucine, isoleucine, proline, phenylalanine, methionine, tryptophan), beta-branched side chains (e.g., threonine, valine, isoleucine) and aromatic side chains (e.g., tyrosine, phenylalanine, tryptophan, histidine). Alternatively, mutations can be introduced randomly along all or part of the coding sequence, such as by saturation mutagenesis, and the resultant mutants can be screened for biological activity to identify mutants that retain activity. Following mutagenesis, the encoded protein can be expressed recombinantly and the activity of the protein can be determined.

[0165] The present invention encompasses antisense nucleic acid molecules, i.e., molecules which are complementary to a sense nucleic acid of the invention, e.g., complementary to the coding strand of a double-stranded marker cDNA molecule or complementary to a marker mRNA sequence. Accordingly, an antisense nucleic acid of the invention can hydrogen bond to (i.e. anneal with) a sense nucleic acid of the invention. The antisense nucleic acid can be complementary to an entire coding strand, or to only a portion thereof, e.g., all or part of the protein coding region (or open reading frame). An antisense nucleic acid molecule can also be antisense to all or part of a non-coding region of the coding strand of a nucleotide sequence encoding a marker protein. The non-coding regions (“5′ and 3′ untranslated regions”) are the 5′ and 3′ sequences which flank the coding region and are not translated into amino acids.

[0166] An antisense oligonucleotide can be, for example, about 5, 10, 15, 20, 25, 30, 35, 40, 45, or 50 or more nucleotides in length. An antisense nucleic acid of the invention can be constructed using chemical synthesis and enzymatic ligation reactions using procedures known in the art. For example, an antisense nucleic acid (e.g., an antisense oligonucleotide) can be chemically synthesized using naturally occurring nucleotides or variously modified nucleotides designed to increase the biological stability of the molecules or to increase the physical stability of the duplex formed between the antisense and sense nucleic acids, e.g., phosphorothioate derivatives and acridine substituted nucleotides can be used. Examples of modified nucleotides which can be used to generate the antisense nucleic acid include 5-fluorouracil, 5-bromouracil, 5-chlorouracil, 5-iodouracil, hypoxanthine, xanthine, 4-acetylcytosine, 5-(carboxyhydroxylmethyl) uracil, 5-carboxymethylaminomethyl-2-thiouridine, 5-carboxymethylaminomethyluracil, dihydrouracil, beta-D-galactosylqueosine, inosine, N6-isopentenyladenine, 1-methylguanine, 1-methylinosine, 2,2-dimethylguanine, 2-methyladenine, 2-methylguanine, 3-methylcytosine, 5-methylcytosine, N6-adenine, 7-methylguanine, 5-methylaminomethyluracil, 5-methoxyaminomethyl-2-thiouracil, beta-D-mannosylqueosine, S′-methoxycarboxymethyluracil, S-methoxyuracil, 2-methylthio-N6-isopentenyladenine, uracil-5-oxyacetic acid (v), wybutoxosine, pseudouracil, queosine, 2-thiocytosine, 5-methyl-2-thiouracil, 2-thiouracil, 4-thiouracil, 5-methyluracil, uracil-5-oxyacetic acid methylester, uracil-5-oxyacetic acid (v), 5-methyl-2-thiouracil, 3-(3-amino-3-N-2-carboxypropyl) uracil, (acp3)w, and 2,6-diaminopurine. Alternatively, the antisense nucleic acid can be produced biologically using an expression vector into which a nucleic acid has been sub-cloned in an antisense orientation (i.e., RNA transcribed from the inserted nucleic acid will be of an antisense orientation to a target nucleic acid of interest, described further in the following subsection).

[0167] The antisense nucleic acid molecules of the invention are typically administered to a subject or generated in situ such that they hybridize with or bind to cellular mRNA and/or genomic DNA encoding a marker protein to thereby inhibit expression of the marker, e.g., by inhibiting transcription and/or translation. The hybridization can be by conventional nucleotide complementarity to form a stable duplex, or, for example, in the case of an antisense nucleic acid molecule which binds to DNA duplexes, through specific interactions in the major groove of the double helix. Examples of a route of administration of antisense nucleic acid molecules of the invention includes direct injection at a tissue site or infusion of the antisense nucleic acid into a colon-associated body fluid. Alternatively, antisense nucleic acid molecules can be modified to target selected cells and then administered systemically. For example, for systemic administration, antisense molecules can be modified such that they specifically bind to receptors or antigens expressed on a selected cell surface, e.g., by linking the antisense nucleic acid molecules to peptides or antibodies which bind to cell surface receptors or antigens. The antisense nucleic acid molecules can also be delivered to cells using the vectors described herein. To achieve sufficient intracellular concentrations of the antisense molecules, vector constructs in which the antisense nucleic acid molecule is placed under the control of a strong pol II or pol III promoter are preferred.

[0168] An antisense nucleic acid molecule of the invention can be an α-anomeric nucleic acid molecule. An α-anomeric nucleic acid molecule forms specific double-stranded hybrids with complementary RNA in which, contrary to the usual a-units, the strands run parallel to each other (Gaultier et al., 1987, Nucleic Acids Res. 15:6625-6641). The antisense nucleic acid molecule can also comprise a 2′-o-methylribonucleotide (Inoue et al., 1987, Nucleic Acids Res. 15:6131-6148) or a chimeric RNA-DNA analogue (Inoue et al., 1987, FEBS Lett. 215:327-330).

[0169] The invention also encompasses ribozymes. Ribozymes are catalytic RNA molecules with ribonuclease activity which are capable of cleaving a single-stranded nucleic acid, such as an mRNA, to which they have a complementary region. Thus, ribozymes (e.g., hammerhead ribozymes as described in Haselhoff and Gerlach, 1988, Nature 334:585-591) can be used to catalytically cleave mRNA transcripts to thereby inhibit translation of the protein encoded by the mRNA. A ribozyme having specificity for a nucleic acid molecule encoding a marker protein can be designed based upon the nucleotide sequence of a cDNA corresponding to the marker. For example, a derivative of a Tetrahymena L-19 IVS RNA can be constructed in which the nucleotide sequence of the active site is complementary to the nucleotide sequence to be cleaved (see Cech et al. U.S. Pat. No. 4,987,071; and Cech et al. U.S. Pat. No. 5,116,742). Alternatively, an mRNA encoding a polypeptide of the invention can be used to select a catalytic RNA having a specific ribonuclease activity from a pool of RNA molecules (see, e.g., Bartel and Szostak, 1993, Science 261:1411-1418).

[0170] The invention also encompasses nucleic acid molecules which form triple helical structures. For example, expression of a marker of the invention can be inhibited by targeting nucleotide sequences complementary to the regulatory region of the gene encoding the marker nucleic acid or protein (e.g., the promoter and/or enhancer) to form triple helical structures that prevent transcription of the gene in target cells. See generally Helene (1991) Anticancer Drug Des. 6(6):569-84; Helene (1992) Ann. N.Y. Acad. Sci. 660:27-36; and Maher (1992) Bioassays 14(12):807-15.

[0171] In various embodiments, the nucleic acid molecules of the invention can be modified at the base moiety, sugar moiety or phosphate backbone to improve, e.g., the stability, hybridization, or solubility of the molecule. For example, the deoxyribose phosphate backbone of the nucleic acids can be modified to generate peptide nucleic acids (see Hyrup et al., 1996, Bioorganic & Medicinal Chemistry 4(1): 5-23). As used herein, the terms “peptide nucleic acids” or “PNAs” refer to nucleic acid mimics, e.g., DNA mimics, in which the deoxyribose phosphate backbone is replaced by a pseudopeptide backbone and only the four natural nucleobases are retained. The neutral backbone of PNAs has been shown to allow for specific hybridization to DNA and RNA under conditions of low ionic strength. The synthesis of PNA oligomers can be performed using standard solid phase peptide synthesis protocols as described in Hyrup et al. (1996), supra; Perry-O'Keefe et al. (1996) Proc. Natl. Acad. Sci. USA 93:14670-675.

[0172] PNAs can be used in therapeutic and diagnostic applications. For example, PNAs can be used as antisense or antigene agents for sequence-specific modulation of gene expression by, e.g., inducing transcription or translation arrest or inhibiting replication. PNAs can also be used, e.g., in the analysis of single base pair mutations in a gene by, e.g., PNA directed PCR clamping; as artificial restriction enzymes when used in combination with other enzymes, e.g., S1 nucleases (Hyrup (1996), supra; or as probes or primers for DNA sequence and hybridization (Hyrup, 1996, supra; Perry-O'Keefe et al., 1996, Proc. Natl. Acad. Sci. USA 93:14670-675).

[0173] In another embodiment, PNAs can be modified, e.g., to enhance their stability or cellular uptake, by attaching lipophilic or other helper groups to PNA, by the formation of PNA-DNA chimeras, or by the use of liposomes or other techniques of drug delivery known in the art. For example, PNA-DNA chimeras can be generated which can combine the advantageous properties of PNA and DNA. Such chimeras allow DNA recognition enzymes, e.g., RNase H and DNA polymerases, to interact with the DNA portion while the PNA portion would provide high binding affinity and specificity. PNA-DNA chimeras can be linked using linkers of appropriate lengths selected in terms of base stacking, number of bonds between the nucleobases, and orientation (Hyrup, 1996, supra). The synthesis of PNA-DNA chimeras can be performed as described in Hyrup (1996), supra, and Finn et al. (1996) Nucleic Acids Res. 24(17):3357-63. For example, a DNA chain can be synthesized on a solid support using standard phosphoramidite coupling chemistry and modified nucleoside analogs. Compounds such as 5′-(4-methoxytrityl)amino-5′-deoxy-thymidine phosphoramidite can be used as a link between the PNA and the 5′ end of DNA (Mag et al., 1989, Nucleic Acids Res. 17:5973-88). PNA monomers are then coupled in a step-wise manner to produce a chimeric molecule with a 5′ PNA segment and a 3′ DNA segment (Finn et al., 1996, Nucleic Acids Res. 24(17):3357-63). Alternatively, chimeric molecules can be synthesized with a 5′ DNA segment and a 3′ PNA segment (Peterser et al., 1975, Bioorganic Med. Chem. Lett. 5:1119-11124).

[0174] In other embodiments, the oligonucleotide can include other appended groups such as peptides (e.g., for targeting host cell receptors in vivo), or agents facilitating transport across the cell membrane (see, e.g., Letsinger et al., 1989, Proc. Natl. Acad. Sci. USA 86:6553-6556; Lemaitre et al., 1987, Proc. Natl. Acad. Sci. USA 84:648-652; PCT Publication No. WO 88/09810) or the blood-brain barrier (see, e.g., PCT Publication No. WO 89/10134). In addition, oligonucleotides can be modified with hybridization-triggered cleavage agents (see, e.g., Krol et al., 1988, Bio/Techniques 6:958-976) or intercalating agents (see, e.g., Zon, 1988, Pharm. Res. 5:539-549). To this end, the oligonucleotide can be conjugated to another molecule, e.g., a peptide, hybridization triggered cross-linking agent, transport agent, hybridization-triggered cleavage agent, etc.

[0175] The invention also includes molecular beacon nucleic acids having at least one region which is complementary to a nucleic acid of the invention, such that the molecular beacon is useful for quantitating the presence of the nucleic acid of the invention in a sample. A “molecular beacon” nucleic acid is a nucleic acid comprising a pair of complementary regions and having a fluorophore and a fluorescent quencher associated therewith. The fluorophore and quencher are associated with different portions of the nucleic acid in such an orientation that when the complementary regions are annealed with one another, fluorescence of the fluorophore is quenched by the quencher. When the complementary regions of the nucleic acid are not annealed with one another, fluorescence of the fluorophore is quenched to a lesser degree. Molecular beacon nucleic acids are described, for example, in U.S. Pat. No. 5,876,930.

[0176] II. Isolated Proteins and Antibodies

[0177] One aspect of the invention pertains to isolated marker proteins and biologically active portions thereof, as well as polypeptide fragments suitable for use as immunogens to raise antibodies directed against a marker protein or a fragment thereof. In one embodiment, the native marker protein can be isolated from cells or tissue sources by an appropriate purification scheme using standard protein purification techniques. In another embodiment, a protein or peptide comprising the whole or a segment of the marker protein is produced by recombinant DNA techniques. Alternative to recombinant expression, such protein or peptide can be synthesized chemically using standard peptide synthesis techniques.

[0178] An “isolated” or “purified” protein or biologically active portion thereof is substantially free of cellular material or other contaminating proteins from the cell or tissue source from which the protein is derived, or substantially free of chemical precursors or other chemicals when chemically synthesized. The language “substantially free of cellular material” includes preparations of protein in which the protein is separated from cellular components of the cells from which it is isolated or recombinantly produced. Thus, protein that is substantially free of cellular material includes preparations of protein having less than about 30%, 20%, 10%, or 5% (by dry weight) of heterologous protein (also referred to herein as a “contaminating protein”). When the protein or biologically active portion thereof is recombinantly produced, it is also preferably substantially free of culture medium, i.e., culture medium represents less than about 20%, 10%, or 5% of the volume of the protein preparation. When the protein is produced by chemical synthesis, it is preferably substantially free of chemical precursors or other chemicals, i.e., it is separated from chemical precursors or other chemicals which are involved in the synthesis of the protein. Accordingly such preparations of the protein have less than about 30%, 20%, 10%, 5% (by dry weight) of chemical precursors or compounds other than the polypeptide of interest.

[0179] Biologically active portions of a marker protein include polypeptides comprising amino acid sequences sufficiently identical to or derived from the amino acid sequence of the marker protein, which include fewer amino acids than the full length protein, and exhibit at least one activity of the corresponding full-length protein. Typically, biologically active portions comprise a domain or motif with at least one activity of the corresponding full-length protein. A biologically active portion of a marker protein of the invention can be a polypeptide which is, for example, 10, 25, 50, 100 or more amino acids in length. Moreover, other biologically active portions, in which other regions of the marker protein are deleted, can be prepared by recombinant techniques and evaluated for one or more of the functional activities of the native form of the marker protein.

[0180] Other useful proteins are substantially identical (e.g., at least about 40%, preferably 50%, 60%, 70%, 80%, 90%, 95%, or 99%) to a marker protein and retain the functional activity of the corresponding naturally-occurring marker protein yet differ in amino acid sequence due to natural allelic variation or mutagenesis.

[0181] To determine the percent identity of two amino acid sequences or of two nucleic acids, the sequences are aligned for optimal comparison purposes (e.g., gaps can be introduced in the sequence of a first amino acid or nucleic acid sequence for optimal alignment with a second amino or nucleic acid sequence). The amino acid residues or nucleotides at corresponding amino acid positions or nucleotide positions are then compared. When a position in the first sequence is occupied by the same amino acid residue or nucleotide as the corresponding position in the second sequence, then the molecules are identical at that position. The percent identity between the two sequences is a function of the number of identical positions shared by the sequences (i.e., % identity=# of identical positions/total # of positions (e.g., overlapping positions)×100). In one embodiment the two sequences are the same length.

[0182] The determination of percent identity between two sequences can be accomplished using a mathematical algorithm. A preferred, non-limiting example of a mathematical algorithm utilized for the comparison of two sequences is the algorithm of Karlin and Altschul (1990) Proc. Natl. Acad. Sci. USA 87:2264-2268, modified as in Karlin and Altschul (1993) Proc. Natl. Acad. Sci. USA 90:5873-5877. Such an algorithm is incorporated into the BLASTN and BLASTX programs of Altschul, et al. (1990) J. Mol. Biol. 215:403-410. BLAST nucleotide searches can be performed with the BLASTN program, score=100, wordlength=12 to obtain nucleotide sequences homologous to a nucleic acid molecules of the invention. BLAST protein searches can be performed with the BLASTP program, score=50, wordlength=3 to obtain amino acid sequences homologous to a protein molecules of the invention. To obtain gapped alignments for comparison purposes, a newer version of the BLAST algorithm called Gapped BLAST can be utilized as described in Altschul et al. (1997) Nucleic Acids Res. 25:3389-3402, which is able to perform gapped local alignments for the programs BLASTN, BLASTP and BLASTX. Alternatively, PSI-Blast can be used to perform an iterated search which detects distant relationships between molecules. When utilizing BLAST, Gapped BLAST, and PSI-Blast programs, the default parameters of the respective programs (e.g., BLASTX and BLASTN) can be used. See http://www.ncbi.nlm.nih.gov. Another preferred, non-limiting example of a mathematical algorithm utilized for the comparison of sequences is the algorithm of Myers and Miller, (1988) CABIOS 4:11-17. Such an algorithm is incorporated into the ALIGN program (version 2.0) which is part of the GCG sequence alignment software package. When utilizing the ALIGN program for comparing amino acid sequences, a PAM120 weight residue table, a gap length penalty of 12, and a gap penalty of 4 can be used. Yet another useful algorithm for identifying regions of local sequence similarity and alignment is the FASTA algorithm as described in Pearson and Lipman (1988) Proc. Nat. Acad. Sci. USA 85:2444-2448. When using the FASTA algorithm for comparing nucleotide or amino acid sequences, a PAM120 weight residue table can, for example, be used with a k-tuple value of 2.

[0183] The percent identity between two sequences can be determined using techniques similar to those described above, with or without allowing gaps. In calculating percent identity, only exact matches are counted.

[0184] The invention also provides chimeric or fusion proteins comprising a marker protein or a segment thereof. As used herein, a “chimeric protein” or “fusion protein” comprises all or part (preferably a biologically active part) of a marker protein operably linked to a heterologous polypeptide (i.e., a polypeptide other than the marker protein). Within the fusion protein, the term “operably linked” is intended to indicate that the marker protein or segment thereof and the heterologous polypeptide are fused in-frame to each other. The heterologous polypeptide can be fused to the amino-terminus or the carboxyl-terminus of the marker protein or segment.

[0185] One useful fusion protein is a GST fusion protein in which a marker protein or segment is fused to the carboxyl terminus of GST sequences. Such fusion proteins can facilitate the purification of a recombinant polypeptide of the invention.

[0186] In another embodiment, the fusion protein contains a heterologous signal sequence at its amino terminus. For example, the native signal sequence of a marker protein can be removed and replaced with a signal sequence from another protein. For example, the gp67 secretory sequence of the baculovirus envelope protein can be used as a heterologous signal sequence (Ausubel et al., ed., Current Protocols in Molecular Biology, John Wiley & Sons, NY, 1992). Other examples of eukaryotic heterologous signal sequences include the secretory sequences of melittin and human placental alkaline phosphatase (Stratagene; La Jolla, Calif.). In yet another example, useful prokaryotic heterologous signal sequences include the phoA secretory signal (Sambrook et al., supra) and the protein A secretory signal (Pharmacia Biotech; Piscataway, N.J.).

[0187] In yet another embodiment, the fusion protein is an immunoglobulin fusion protein in which all or part of a marker protein is fused to sequences derived from a member of the immunoglobulin protein family. The immunoglobulin fusion proteins of the invention can be incorporated into pharmaceutical compositions and administered to a subject to inhibit an interaction between a ligand (soluble or membrane-bound) and a protein on the surface of a cell (receptor), to thereby suppress signal transduction in vivo. The immunoglobulin fusion protein can be used to affect the bioavailability of a cognate ligand of a marker protein. Inhibition of ligand/receptor interaction can be useful therapeutically, both for treating proliferative and differentiative disorders and for modulating (e.g. promoting or inhibiting) cell survival. Moreover, the immunoglobulin fusion proteins of the invention can be used as immunogens to produce antibodies directed against a marker protein in a subject, to purify ligands and in screening assays to identify molecules which inhibit the interaction of the marker protein with ligands.

[0188] Chimeric and fusion proteins of the invention can be produced by standard recombinant DNA techniques. In another embodiment, the fusion gene can be synthesized by conventional techniques including automated DNA synthesizers. Alternatively, PCR amplification of gene fragments can be carried out using anchor primers which give rise to complementary overhangs between two consecutive gene fragments which can subsequently be annealed and re-amplified to generate a chimeric gene sequence (see, e.g., Ausubel et al., supra). Moreover, many expression vectors are commercially available that already encode a fusion moiety (e.g., a GST polypeptide). A nucleic acid encoding a polypeptide of the invention can be cloned into such an expression vector such that the fusion moiety is linked in-frame to the polypeptide of the invention.

[0189] A signal sequence can be used to facilitate secretion and isolation of marker proteins. Signal sequences are typically characterized by a core of hydrophobic amino acids which are generally cleaved from the mature protein during secretion in one or more cleavage events. Such signal peptides contain processing sites that allow cleavage of the signal sequence from the mature proteins as they pass through the secretory pathway. Thus, the invention pertains to marker proteins, fusion proteins or segments thereof having a signal sequence, as well as to such proteins from which the signal sequence has been proteolytically cleaved (i.e., the cleavage products). In one embodiment, a nucleic acid sequence encoding a signal sequence can be operably linked in an expression vector to a protein of interest, such as a marker protein or a segment thereof. The signal sequence directs secretion of the protein, such as from a eukaryotic host into which the expression vector is transformed, and the signal sequence is subsequently or concurrently cleaved. The protein can then be readily purified from the extracellular medium by art recognized methods. Alternatively, the signal sequence can be linked to the protein of interest using a sequence which facilitates purification, such as with a GST domain.

[0190] The present invention also pertains to variants of the marker proteins. Such variants have an altered amino acid sequence which can function as either agonists (mimetics) or as antagonists. Variants can be generated by mutagenesis, e.g., discrete point mutation or truncation. An agonist can retain substantially the same, or a subset, of the biological activities of the naturally occurring form of the protein. An antagonist of a protein can inhibit one or more of the activities of the naturally occurring form of the protein by, for example, competitively binding to a downstream or upstream member of a cellular signaling cascade which includes the protein of interest. Thus, specific biological effects can be elicited by treatment with a variant of limited function. Treatment of a subject with a variant having a subset of the biological activities of the naturally occurring form of the protein can have fewer side effects in a subject relative to treatment with the naturally occurring form of the protein.

[0191] Variants of a marker protein which function as either agonists (mimetics) or as antagonists can be identified by screening combinatorial libraries of mutants, e.g., truncation mutants, of the protein of the invention for agonist or antagonist activity. In one embodiment, a variegated library of variants is generated by combinatorial mutagenesis at the nucleic acid level and is encoded by a variegated gene library. A variegated library of variants can be produced by, for example, enzymatically ligating a mixture of synthetic oligonucleotides into gene sequences such that a degenerate set of potential protein sequences is expressible as individual polypeptides, or alternatively, as a set of larger fusion proteins (e.g., for phage display). There are a variety of methods which can be used to produce libraries of potential variants of the marker proteins from a degenerate oligonucleotide sequence. Methods for synthesizing degenerate oligonucleotides are known in the art (see, e.g., Narang, 1983, Tetrahedron 39:3; Itakura et al., 1984, Annu. Rev. Biochem. 53:323; Itakura et al., 1984, Science 198:1056; Ike et al., 1983 Nucleic Acid Res. 11:477).

[0192] In addition, libraries of segments of a marker protein can be used to generate a variegated population of polypeptides for screening and subsequent selection of variant marker proteins or segments thereof. For example, a library of coding sequence fragments can be generated by treating a double stranded PCR fragment of the coding sequence of interest with a nuclease under conditions wherein nicking occurs only about once per molecule, denaturing the double stranded DNA, renaturing the DNA to form double stranded DNA which can include sense/antisense pairs from different nicked products, removing single stranded portions from reformed duplexes by treatment with S1 nuclease, and ligating the resulting fragment library into an expression vector. By this method, an expression library can be derived which encodes amino terminal and internal fragments of various sizes of the protein of interest.

[0193] Several techniques are known in the art for screening gene products of combinatorial libraries made by point mutations or truncation, and for screening cDNA libraries for gene products having a selected property. The most widely used techniques, which are amenable to high through-put analysis, for screening large gene libraries typically include cloning the gene library into replicable expression vectors, transforming appropriate cells with the resulting library of vectors, and expressing the combinatorial genes under conditions in which detection of a desired activity facilitates isolation of the vector encoding the gene whose product was detected. Recursive ensemble mutagenesis (REM), a technique which enhances the frequency of functional mutants in the libraries, can be used in combination with the screening assays to identify variants of a protein of the invention (Arkin and Yourvan, 1992, Proc. Natl. Acad. Sci. USA 89:7811-7815; Delgrave et al, 1993, Protein Engineering 6(3):327-331).

[0194] Another aspect of the invention pertains to antibodies directed against a protein of the invention. In preferred embodiments, the antibodies specifically bind a marker protein or a fragment thereof. The terms “antibody” and “antibodies” as used interchangeably herein refer to immunoglobulin molecules as well as fragments and derivatives thereof that comprise an immunologically active portion of an immunoglobulin molecule, (i.e., such a portion contains an antigen binding site which specifically binds an antigen, such as a marker protein, e.g., an epitope of a marker protein). An antibody which specifically binds to a protein of the invention is an antibody which binds the protein, but does not substantially bind other molecules in a sample, e.g., a biological sample, which naturally contains the protein. Examples of an immunologically active portion of an immunoglobulin molecule include, but are not limited to, single-chain antibodies (scAb), F(ab) and F(ab′)2 fragments.

[0195] An isolated protein of the invention or a fragment thereof can be used as an immunogen to generate antibodies. The full-length protein can be used or, alternatively, the invention provides antigenic peptide fragments for use as immunogens. The antigenic peptide of a protein of the invention comprises at least 8 (preferably 10, 15, 20, or 30 or more) amino acid residues of the amino acid sequence of one of the proteins of the invention, and encompasses at least one epitope of the protein such that an antibody raised against the peptide forms a specific immune complex with the protein. Preferred epitopes encompassed by the antigenic peptide are regions that are located on the surface of the protein, e.g., hydrophilic regions. Hydrophobicity sequence analysis, hydrophilicity sequence analysis, or similar analyses can be used to identify hydrophilic regions. In preferred embodiments, an isolated marker protein or fragment thereof is used as an immunogen.

[0196] An immunogen typically is used to prepare antibodies by immunizing a suitable (i.e. immunocompetent) subject such as a rabbit, goat, mouse, or other mammal or vertebrate. An appropriate immunogenic preparation can contain, for example, recombinantly-expressed or chemically-synthesized protein or peptide. The preparation can further include an adjuvant, such as Freund's complete or incomplete adjuvant, or a similar immunostimulatory agent. Preferred immunogen compositions are those that contain no other human proteins such as, for example, immunogen compositions made using a non-human host cell for recombinant expression of a protein of the invention. In such a manner, the resulting antibody compositions have reduced or no binding of human proteins other than a protein of the invention.

[0197] The invention provides polyclonal and monoclonal antibodies. The term “monoclonal antibody” or “monoclonal antibody composition”, as used herein, refers to a population of antibody molecules that contain only one species of an antigen binding site capable of immunoreacting with a particular epitope. Preferred polyclonal and monoclonal antibody compositions are ones that have been selected for antibodies directed against a protein of the invention. Particularly preferred polyclonal and monoclonal antibody preparations are ones that contain only antibodies directed against a marker protein or fragment thereof.

[0198] Polyclonal antibodies can be prepared by immunizing a suitable subject with a protein of the invention as an immunogen The antibody titer in the immunized subject can be monitored over time by standard techniques, such as with an enzyme linked immunosorbent assay (ELISA) using immobilized polypeptide. At an appropriate time after immunization, e.g., when the specific antibody titers are highest, antibody-producing cells can be obtained from the subject and used to prepare monoclonal antibodies (mAb) by standard techniques, such as the hybridoma technique originally described by Kohler and Milstein (1975) Nature 256:495-497, 497, the human B cell hybridoma technique (see Kozbor et al., 1983, Immunol. Today 4:72), the EBV-hybridoma technique (see Cole et al., pp. 77-96 In Monoclonal Antibodies and Cancer Therapy, Alan R. Liss, Inc., 1985) or trioma techniques. The technology for producing hybridomas is well known (see generally Current Protocols in Immunology, Coligan et al. ed., John Wiley & Sons, New York, 1994). Hybridoma cells producing a monoclonal antibody of the invention are detected by screening the hybridoma culture supernatants for antibodies that bind the polypeptide of interest, e.g., using a standard ELISA assay.

[0199] Alternative to preparing monoclonal antibody-secreting hybridomas, a monoclonal antibody directed against a protein of the invention can be identified and isolated by screening a recombinant combinatorial immunoglobulin library (e.g., an antibody phage display library) with the polypeptide of interest. Kits for generating and screening phage display libraries are commercially available (e.g., the Pharmacia Recombinant Phage Antibody System, Catalog No. 27-9400-01; and the Stratagene SurfZAP Phage Display Kit, Catalog No. 240612). Additionally, examples of methods and reagents particularly amenable for use in generating and screening antibody display library can be found in, for example, U.S. Pat. No. 5,223,409; PCT Publication No. WO 92/18619; PCT Publication No. WO 91/17271; PCT Publication No. WO 92/20791; PCT Publication No. WO 92/15679; PCT Publication No. WO 93/01288; PCT Publication No. WO 92/01047; PCT Publication No. WO 92/09690; PCT Publication No. WO 90/02809; Fuchs et al. (1991) Bio/Technology 9:1370-1372; Hay et al. (1992) Hum. Antibod. Hybridomas 3:81-85; Huse et al. (1989) Science 246:1275-1281; Griffiths et al. (1993) EMBO J. 12:725-734.

[0200] The invention also provides recombinant antibodies that specifically bind a protein of the invention. In preferred embodiments, the recombinant antibodies specifically binds a marker protein or fragment thereof. Recombinant antibodies include, but are not limited to, chimeric and humanized monoclonal antibodies, comprising both human and non-human portions, single-chain antibodies and multi-specific antibodies. A chimeric antibody is a molecule in which different portions are derived from different animal species, such as those having a variable region derived from a murine mAb and a human immunoglobulin constant region. (See, e.g., Cabilly et al., U.S. Pat. No. 4,816,567; and Boss et al., U.S. Pat. No. 4,816,397, which are incorporated herein by reference in their entirety.) Single-chain antibodies have an antigen binding site and consist of a single polypeptide. They can be produced by techniques known in the art, for example using methods described in Ladner et. al U.S. Pat. No. 4,946,778 (which is incorporated herein by reference in its entirety); Bird et al., (1988) Science 242:423-426; Whitlow et al., (1991) Methods in Enzymology 2:1-9; Whitlow et al., (1991) Methods in Enzymology 2:97-105; and Huston et al., (1991) Methods in Enzymology Molecular Design and Modeling: Concepts and Applications 203:46-88. Multi-specific antibodies are antibody molecules having at least two antigen-binding sites that specifically bind different antigens. Such molecules can be produced by techniques known in the art, for example using methods described in Segal, U.S. Pat. No. 4,676,980 (the disclosure of which is incorporated herein by reference in its entirety); Holliger et al., (1993) Proc. Natl. Acad. Sci. USA 90:6444-6448; Whitlow et al., (1994) Protein Eng. 7:1017-1026 and U.S. Pat. No. 6,121,424.

[0201] Humanized antibodies are antibody molecules from non-human species having one or more complementarity determining regions (CDRs) from the non-human species and a framework region from a human immunoglobulin molecule. (See, e.g., Queen, U.S. Pat. No. 5,585,089, which is incorporated herein by reference in its entirety.) Humanized monoclonal antibodies can be produced by recombinant DNA techniques known in the art, for example using methods described in PCT Publication No. WO 87/02671; European Patent Application 184,187; European Patent Application 171,496; European Patent Application 173,494; PCT Publication No. WO 86/01533; U.S. Pat. No. 4,816,567; European Patent Application 125,023; Better et al. (1988) Science 240:1041-1043; Liu et al. (1987) Proc. Natl. Acad. Sci. USA 84:3439-3443; Liu et al. (1987) J. Immunol. 139:3521-3526; Sun et al. (1987) Proc. Natl. Acad. Sci. USA 84:214-218; Nishimura et al. (1987) Cancer Res. 47:999-1005; Wood et al. (1985) Nature 314:446-449; and Shaw et al. (1988) J. Natl. Cancer Inst. 80:1553-1559); Morrison (1985) Science 229:1202-1207; Oi et al. (1986) Bio/Techniques 4:214; U.S. Pat. No. 5,225,539; Jones et al. (1986) Nature 321:552-525; Verhoeyan et al. (1988) Science 239:1534; and Beidler et al. (1988) J. Immunol. 141:4053-4060.

[0202] More particularly, humanized antibodies can be produced, for example, using transgenic mice which are incapable of expressing endogenous immunoglobulin heavy and light chains genes, but which can express human heavy and light chain genes. The transgenic mice are immunized in the normal fashion with a selected antigen, e.g., all or a portion of a polypeptide corresponding to a marker of the invention. Monoclonal antibodies directed against the antigen can be obtained using conventional hybridoma technology. The human immunoglobulin transgenes harbored by the transgenic mice rearrange during B cell differentiation, and subsequently undergo class switching and somatic mutation. Thus, using such a technique, it is possible to produce therapeutically useful IgG, IgA and IgE antibodies. For an overview of this technology for producing human antibodies, see Lonberg and Huszar (1995) Int. Rev. Immunol. 13:65-93). For a detailed discussion of this technology for producing human antibodies and human monoclonal antibodies and protocols for producing such antibodies, see, e.g., U.S. Pat. No. 5,625,126; U.S. Pat. No. 5,633,425; U.S. Pat. No. 5,569,825; U.S. Pat. No. 5,661,016; and U.S. Pat. No. 5,545,806. In addition, companies such as Abgenix, Inc. (Freemont, Calif.), can be engaged to provide human antibodies directed against a selected antigen using technology similar to that described above.

[0203] Completely human antibodies which recognize a selected epitope can be generated using a technique referred to as “guided selection.” In this approach a selected non-human monoclonal antibody, e.g., a murine antibody, is used to guide the selection of a completely human antibody recognizing the same epitope (Jespers et al., 1994, Bio/technology 12:899-903).

[0204] The antibodies of the invention can be isolated after production (e.g., from the blood or serum of the subject) or synthesis and further purified by well-known techniques. For example, IgG antibodies can be purified using protein A chromatography. Antibodies specific for a protein of the invention can be selected or (e.g., partially purified) or purified by, e.g., affinity chromatography. For example, a recombinantly expressed and purified (or partially purified) protein of the invention is produced as described herein, and covalently or non-covalently coupled to a solid support such as, for example, a chromatography column. The column can then be used to affinity purify antibodies specific for the proteins of the invention from a sample containing antibodies directed against a large number of different epitopes, thereby generating a substantially purified antibody composition, i.e., one that is substantially free of contaminating antibodies. By a substantially purified antibody composition is meant, in this context, that the antibody sample contains at most only 30% (by dry weight) of contaminating antibodies directed against epitopes other than those of the desired protein of the invention, and preferably at most 20%, yet more preferably at most 10%, and most preferably at most 5% (by dry weight) of the sample is contaminating antibodies. A purified antibody composition means that at least 99% of the antibodies in the composition are directed against the desired protein of the invention.

[0205] In a preferred embodiment, the substantially purified antibodies of the invention may specifically bind to a signal peptide, a secreted sequence, an extracellular domain, a transmembrane or a cytoplasmic domain or cytoplasmic membrane of a protein of the invention. In a particularly preferred embodiment, the substantially purified antibodies of the invention specifically bind to a secreted sequence or an extracellular domain of the amino acid sequences of a protein of the invention. In a more preferred embodiment, the substantially purified antibodies of the invention specifically bind to a secreted sequence or an extracellular domain of the amino acid sequences of a marker protein.

[0206] An antibody directed against a protein of the invention can be used to isolate the protein by standard techniques, such as affinity chromatography or immunoprecipitation. Moreover, such an antibody can be used to detect the marker protein or fragment thereof (e.g., in a cellular lysate or cell supernatant) in order to evaluate the level and pattern of expression of the marker. The antibodies can also be used diagnostically to monitor protein levels in tissues or body fluids (e.g. in an colorectal-associated body fluid) as part of a clinical testing procedure, e.g., to, for example, determine the efficacy of a given treatment regimen. Detection can be facilitated by the use of an antibody derivative, which comprises an antibody of the invention coupled to a detectable substance. Examples of detectable substances include various enzymes, prosthetic groups, fluorescent materials, luminescent materials, bioluminescent materials, and radioactive materials. Examples of suitable enzymes include horseradish peroxidase, alkaline phosphatase, β-galactosidase, or acetylcholinesterase; examples of suitable prosthetic group complexes include streptavidin/biotin and avidin/biotin; examples of suitable fluorescent materials include umbelliferone, fluorescein, fluorescein isothiocyanate, rhodamine, dichlorotriazinylamine fluorescein, dansyl chloride or phycoerythrin; an example of a luminescent material includes luminol; examples of bioluminescent materials include luciferase, luciferin, and aequorin, and examples of suitable radioactive material include 125I, 131I, 35S or 3H.

[0207] Antibodies of the invention may also be used as therapeutic agents in treating cancers. In a preferred embodiment, completely human antibodies of the invention are used for therapeutic treatment of human cancer patients, particularly those having an colon cancer. In another preferred embodiment, antibodies that bind specifically to a marker protein or fragment thereof are used for therapeutic treatment. Further, such therapeutic antibody may be an antibody derivative or immunotoxin comprising an antibody conjugated to a therapeutic moiety such as a cytotoxin, a therapeutic agent or a radioactive metal ion. A cytotoxin or cytotoxic agent includes any agent that is detrimental to cells. Examples include taxol, cytochalasin B, gramicidin D, ethidium bromide, emetine, mitomycin, etoposide, tenoposide, vincristine, vinblastine, colchicin, doxorubicin, daunorubicin, dihydroxy anthracin dione, mitoxantrone, mithramycin, actinomycin D, 1-dehydrotestosterone, glucocorticoids, procaine, tetracaine, lidocaine, propranolol, and puromycin and analogs or homologs thereof. Therapeutic agents include, but are not limited to, antimetabolites (e.g., methotrexate, 6-mercaptopurine, 6-thioguanine, cytarabine, 5-fluorouracil decarbazine), alkylating agents (e.g., mechlorethamine, thioepa chlorambucil, melphalan, carmustine (BSNU) and lomustine (CCNU), cyclothosphamide, busulfan, dibromomannitol, streptozotocin, mitomycin C, and cis-dichlorodiamine platinum (II) (DDP) cisplatin), anthracyclines (e.g., daunorubicin (formerly daunomycin) and doxorubicin), antibiotics (e.g., dactinomycin (formerly actinomycin), bleomycin, mithramycin, and anthramycin (AMC)), and anti-mitotic agents (e.g., vincristine and vinblastine).

[0208] The conjugated antibodies of the invention can be used for modifying a given biological response, for the drug moiety is not to be construed as limited to classical chemical therapeutic agents. For example, the drug moiety may be a protein or polypeptide possessing a desired biological activity. Such proteins may include, for example, a toxin such as ribosome-inhibiting protein (see Better et al., U.S. Pat. No. 6,146,631, the disclosure of which is incorporated herein in its entirety), abrin, ricin A, pseudomonas exotoxin, or diphtheria toxin; a protein such as tumor necrosis factor, .alpha.-interferon, .beta.-interferon, nerve growth factor, platelet derived growth factor, tissue plasminogen activator; or, biological response modifiers such as, for example, lymphokines, interleukin-1 (“IL-1”), interleukin-2 (“IL-2”), interleukin-6 (“IL-6”), granulocyte macrophase colony stimulating factor (“GM-CSF”), granulocyte colony stimulating factor (“G-CSF”), or other growth factors.

[0209] Techniques for conjugating such therapeutic moiety to antibodies are well known, see, e.g., Arnon et al., “Monoclonal Antibodies For Immunotargeting Of Drugs In Cancer Therapy”, in Monoclonal Antibodies And Cancer Therapy, Reisfeld et al. (eds.), pp. 243-56 (Alan R. Liss, Inc. 1985); Hellstrom et al., “Antibodies For Drug Delivery”, in Controlled Drug Delivery (2nd Ed.), Robinson et al. (eds.), pp. 623-53 (Marcel Dekker, Inc. 1987); Thorpe, “Antibody Carriers Of Cytotoxic Agents In Cancer Therapy: A Review”, in Monoclonal Antibodies 84: Biological And Clinical Applications, Pinchera et al. (eds.), pp. 475-506 (1985); “Analysis, Results, And Future Prospective Of The Therapeutic Use Of Radiolabeled Antibody In Cancer Therapy”, in Monoclonal Antibodies For Cancer Detection And Therapy, Baldwin et al. (eds.), pp. 303-16 (Academic Press 1985), and Thorpe et al., “The Preparation And Cytotoxic Properties Of Antibody-Toxin Conjugates”, Immunol. Rev., 62:119-58 (1982).

[0210] Accordingly, in one aspect, the invention provides substantially purified antibodies, antibody fragments and derivatives, all of which specifically bind to a protein of the invention and preferably, a marker protein. In various embodiments, the substantially purified antibodies of the invention, or fragments or derivatives thereof, can be human, non-human, chimeric and/or humanized antibodies. In another aspect, the invention provides non-human antibodies, antibody fragments and derivatives, all of which specifically bind to a protein of the invention and preferably, a marker protein. Such non-human antibodies can be goat, mouse, sheep, horse, chicken, rabbit, or rat antibodies. Alternatively, the non-human antibodies of the invention can be chimeric and/or humanized antibodies. In addition, the non-human antibodies of the invention can be polyclonal antibodies or monoclonal antibodies. In still a further aspect, the invention provides monoclonal antibodies, antibody fragments and derivatives, all of which specifically bind to a protein of the invention and preferably, a marker protein. The monoclonal antibodies can be human, humanized, chimeric and/or non-human antibodies.

[0211] The invention also provides a kit containing an antibody of the invention conjugated to a detectable substance, and instructions for use. Still another aspect of the invention is a pharmaceutical composition comprising an antibody of the invention and a pharmaceutically acceptable carrier. In one embodiment, the pharmaceutical composition contains an antibody of the invention and a pharmaceutically acceptable carrier.

[0212] III. Recombinant Expression Vectors and Host Cells

[0213] Another aspect of the invention pertains to vectors, preferably expression vectors, containing a nucleic acid encoding a marker protein (or a portion of such a protein). As used herein, the term “vector” refers to a nucleic acid molecule capable of transporting another nucleic acid to which it has been linked. One type of vector is a “plasmid”, which refers to a circular double stranded DNA loop into which additional DNA segments can be ligated. Another type of vector is a viral vector, wherein additional DNA segments can be ligated into the viral genome. Certain vectors are capable of autonomous replication in a host cell into which they are introduced (e.g., bacterial vectors having a bacterial origin of replication and episomal mammalian vectors). Other vectors (e.g., non-episomal mammalian vectors) are integrated into the genome of a host cell upon introduction into the host cell, and thereby are replicated along with the host genome. Moreover, certain vectors, namely expression vectors, are capable of directing the expression of genes to which they are operably linked. In general, expression vectors of utility in recombinant DNA techniques are often in the form of plasmids (vectors). However, the invention is intended to include such other forms of expression vectors, such as viral vectors (e.g., replication defective retroviruses, adenoviruses and adeno-associated viruses), which serve equivalent functions.

[0214] The recombinant expression vectors of the invention comprise a nucleic acid of the invention in a form suitable for expression of the nucleic acid in a host cell. This means that the recombinant expression vectors include one or more regulatory sequences, selected on the basis of the host cells to be used for expression, which is operably linked to the nucleic acid sequence to be expressed. Within a recombinant expression vector, “operably linked” is intended to mean that the nucleotide sequence of interest is linked to the regulatory sequence(s) in a manner which allows for expression of the nucleotide sequence (e.g., in an in vitro transcription/translation system or in a host cell when the vector is introduced into the host cell). The term “regulatory sequence” is intended to include promoters, enhancers and other expression control elements (e.g., polyadenylation signals). Such regulatory sequences are described, for example, in Goeddel, Methods in Enzymology: Gene Expression Technology vol. 185, Academic Press, San Diego, Calif. (1991). Regulatory sequences include those which direct constitutive expression of a nucleotide sequence in many types of host cell and those which direct expression of the nucleotide sequence only in certain host cells (e.g., tissue-specific regulatory sequences). It will be appreciated by those skilled in the art that the design of the expression vector can depend on such factors as the choice of the host cell to be transformed, the level of expression of protein desired, and the like. The expression vectors of the invention can be introduced into host cells to thereby produce proteins or peptides, including fusion proteins or peptides, encoded by nucleic acids as described herein.

[0215] The recombinant expression vectors of the invention can be designed for expression of a marker protein or a segment thereof in prokaryotic (e.g., E. coli) or eukaryotic cells (e.g., insect cells {using baculovirus expression vectors}, yeast cells or mammalian cells). Suitable host cells are discussed further in Goeddel, supra. Alternatively, the recombinant expression vector can be transcribed and translated in vitro, for example using T7 promoter regulatory sequences and T7 polymerase.

[0216] Expression of proteins in prokaryotes is most often carried out in E. coli with vectors containing constitutive or inducible promoters directing the expression of either fusion or non-fusion proteins. Fusion vectors add a number of amino acids to a protein encoded therein, usually to the amino terminus of the recombinant protein. Such fusion vectors typically serve three purposes: 1) to increase expression of recombinant protein; 2) to increase the solubility of the recombinant protein; and 3) to aid in the purification of the recombinant protein by acting as a ligand in affinity purification. Often, in fusion expression vectors, a proteolytic cleavage site is introduced at the junction of the fusion moiety and the recombinant protein to enable separation of the recombinant protein from the fusion moiety subsequent to purification of the fusion protein. Such enzymes, and their cognate recognition sequences, include Factor Xa, thrombin and enterokinase. Typical fusion expression vectors include pGEX (Pharmacia Biotech Inc; Smith and Johnson, 1988, Gene 67:31-40), pMAL (New England Biolabs, Beverly, Mass.) and pRIT5 (Pharmacia, Piscataway, N.J.) which fuse glutathione S-transferase (GST), maltose E binding protein, or protein A, respectively, to the target recombinant protein.

[0217] Examples of suitable inducible non-fusion E. coli expression vectors include pTrc (Amann et al., 1988, Gene 69:301-315) and pET 11d (Studier et al., p. 60-89, In Gene Expression Technology: Methods in Enzymology vol.185, Academic Press, San Diego, Calif., 1991). Target gene expression from the pTrc vector relies on host RNA polymerase transcription from a hybrid trp-lac fusion promoter. Target gene expression from the pET 11d vector relies on transcription from a T7 gn10-lac fusion promoter mediated by a co-expressed viral RNA polymerase (T7 gn1). This viral polymerase is supplied by host strains BL21 (DE3) or HMS174(DE3) from a resident prophage harboring a T7 gn1 gene under the transcriptional control of the lacUV 5 promoter.

[0218] One strategy to maximize recombinant protein expression in E. coli is to express the protein in a host bacteria with an impaired capacity to proteolytically cleave the recombinant protein (Gottesman, p. 119-128, In Gene Expression Technology: Methods in Enzymology vol. 185, Academic Press, San Diego, Calif., 1990. Another strategy is to alter the nucleic acid sequence of the nucleic acid to be inserted into an expression vector so that the individual codons for each amino acid are those preferentially utilized in E. coli (Wada et al., 1992, Nucleic Acids Res. 20:2111-2118). Such alteration of nucleic acid sequences of the invention can be carried out by standard DNA synthesis techniques.

[0219] In another embodiment, the expression vector is a yeast expression vector. Examples of vectors for expression in yeast S. cerevisiae include pYepSec1 (Baldari et al., 1987, EMBO J. 6:229-234), pMFa (Kurjan and Herskowitz, 1982, Cell 30:933-943), pJRY88 (Schultz et al., 1987, Gene 54:113-123), pYES2 (Invitrogen Corporation, San Diego, Calif.), and pPicZ (Invitrogen Corp, San Diego, Calif.).

[0220] Alternatively, the expression vector is a baculovirus expression vector. Baculovirus vectors available for expression of proteins in cultured insect cells (e.g., Sf 9 cells) include the pAc series (Smith et al., 1983, Mol. Cell Biol. 3:2156-2165) and the pVL series (Lucklow and Summers, 1989, Virology 170:31-39).

[0221] In yet another embodiment, a nucleic acid of the invention is expressed in mammalian cells using a mammalian expression vector. Examples of mammalian expression vectors include pCDM8 (Seed, 1987, Nature 329:840) and pMT2PC (Kaufman et al., 1987, EMBO J. 6:187-195). When used in mammalian cells, the expression vector's control functions are often provided by viral regulatory elements. For example, commonly used promoters are derived from polyoma, Adenovirus 2, cytomegalovirus and Simian Virus 40. For other suitable expression systems for both prokaryotic and eukaryotic cells see chapters 16 and 17 of Sambrook et al., supra.

[0222] In another embodiment, the recombinant mammalian expression vector is capable of directing expression of the nucleic acid preferentially in a particular cell type (e.g., tissue-specific regulatory elements are used to express the nucleic acid). Tissue-specific regulatory elements are known in the art. Non-limiting examples of suitable tissue-specific promoters include the albumin promoter (liver-specific; Pinkert et al., 1987, Genes Dev. 1:268-277), lymphoid-specific promoters (Calame and Eaton, 1988, Adv. Immunol. 43:235-275), in particular promoters of T cell receptors (Winoto and Baltimore, 1989, EMBO J. 8:729-733) and immunoglobulins (Banerji et al., 1983, Cell 33:729-740; Queen and Baltimore, 1983, Cell 33:741-748), neuron-specific promoters (e.g., the neurofilament promoter; Byrne and Ruddle, 1989, Proc. Natl. Acad. Sci. USA 86:5473-5477), pancreas-specific promoters (Edlund et al., 1985, Science 230:912-916), and mammary gland-specific promoters (e.g., milk whey promoter; U.S. Pat. No. 4,873,316 and European Application Publication No. 264,166). Developmentally-regulated promoters are also encompassed, for example the murine hox promoters (Kessel and Gruss, 1990, Science 249:374-379) and the α-fetoprotein promoter (Camper and Tilghman, 1989, Genes Dev. 3:537-546).

[0223] The invention further provides a recombinant expression vector comprising a DNA molecule of the invention cloned into the expression vector in an antisense orientation. That is, the DNA molecule is operably linked to a regulatory sequence in a manner which allows for expression (by transcription of the DNA molecule) of an RNA molecule which is antisense to the mRNA encoding a polypeptide of the invention. Regulatory sequences operably linked to a nucleic acid cloned in the antisense orientation can be chosen which direct the continuous expression of the antisense RNA molecule in a variety of cell types, for instance viral promoters and/or enhancers, or regulatory sequences can be chosen which direct constitutive, tissue-specific or cell type specific expression of antisense RNA. The antisense expression vector can be in the form of a recombinant plasmid, phagemid, or attenuated virus in which antisense nucleic acids are produced under the control of a high efficiency regulatory region, the activity of which can be determined by the cell type into which the vector is introduced. For a discussion of the regulation of gene expression using antisense genes see Weintraub et al., 1986, Trends in Genetics, Vol. 1(1).

[0224] Another aspect of the invention pertains to host cells into which a recombinant expression vector of the invention has been introduced. The terms “host cell” and “recombinant host cell” are used interchangeably herein. It is understood that such terms refer not only to the particular subject cell but to the progeny or potential progeny of such a cell. Because certain modifications may occur in succeeding generations due to either mutation or environmental influences, such progeny may not, in fact, be identical to the parent cell, but are still included within the scope of the term as used herein.

[0225] A host cell can be any prokaryotic (e.g., E. coli) or eukaryotic cell (e.g., insect cells, yeast or mammalian cells).

[0226] Vector DNA can be introduced into prokaryotic or eukaryotic cells via conventional transformation or transfection techniques. As used herein, the terms “transformation” and “transfection” are intended to refer to a variety of art-recognized techniques for introducing foreign nucleic acid into a host cell, including calcium phosphate or calcium chloride co-precipitation, DEAE-dextran-mediated transfection, lipofection, or electroporation. Suitable methods for transforming or transfecting host cells can be found in Sambrook, et al. (supra), and other laboratory manuals.

[0227] For stable transfection of mammalian cells, it is known that, depending upon the expression vector and transfection technique used, only a small fraction of cells may integrate the foreign DNA into their genome. In order to identify and select these integrants, a gene that encodes a selectable marker (e.g., for resistance to antibiotics) is generally introduced into the host cells along with the gene of interest. Preferred selectable markers include those which confer resistance to drugs, such as G418, hygromycin and methotrexate. Cells stably transfected with the introduced nucleic acid can be identified by drug selection (e.g., cells that have incorporated the selectable marker will survive, while the other cells die).

[0228] A host cell of the invention, such as a prokaryotic or eukaryotic host cell in culture, can be used to produce a marker protein or a segment thereof. Accordingly, the invention further provides methods for producing a marker protein or a segment thereof using the host cells of the invention. In one embodiment, the method comprises culturing the host cell of the invention (into which a recombinant expression vector encoding a marker protein or a segment thereof has been introduced) in a suitable medium such that the is produced. In another embodiment, the method further comprises isolating the a marker protein or a segment thereof from the medium or the host cell.

[0229] The host cells of the invention can also be used to produce nonhuman transgenic animals. For example, in one embodiment, a host cell of the invention is a fertilized oocyte or an embryonic stem cell into which a sequences encoding a marker protein or a segment thereof have been introduced. Such host cells can then be used to create non-human transgenic animals in which exogenous sequences encoding a marker protein of the invention have been introduced into their genome or homologous recombinant animals in which endogenous gene(s) encoding a marker protein have been altered. Such animals are useful for studying the function and/or activity of the marker protein and for identifying and/or evaluating modulators of marker protein. As used herein, a “transgenic animal” is a non-human animal, preferably a mammal, more preferably a rodent such as a rat or mouse, in which one or more of the cells of the animal includes a transgene. Other examples of transgenic animals include non-human primates, sheep, dogs, cows, goats, chickens, amphibians, etc. A transgene is exogenous DNA which is integrated into the genome of a cell from which a transgenic animal develops and which remains in the genome of the mature animal, thereby directing the expression of an encoded gene product in one or more cell types or tissues of the transgenic animal. As used herein, an “homologous recombinant animal” is a non-human animal, preferably a mammal, more preferably a mouse, in which an endogenous gene has been altered by homologous recombination between the endogenous gene and an exogenous DNA molecule introduced into a cell of the animal, e.g., an embryonic cell of the animal, prior to development of the animal.

[0230] A transgenic animal of the invention can be created by introducing a nucleic acid encoding a marker protein into the male pronuclei of a fertilized oocyte, e.g., by microinjection, retroviral infection, and allowing the oocyte to develop in a pseudopregnant female foster animal. Intronic sequences and polyadenylation signals can also be included in the transgene to increase the efficiency of expression of the transgene. A tissue-specific regulatory sequence(s) can be operably linked to the transgene to direct expression of the polypeptide of the invention to particular cells. Methods for generating transgenic animals via embryo manipulation and microinjection, particularly animals such as mice, have become conventional in the art and are described, for example, in U.S. Pat. Nos. 4,736,866 and 4,870,009, U.S. Pat. No. 4,873,191 and in Hogan, Manipulating the Mouse Embryo, Cold Spring Harbor Laboratory Press, Cold Spring Harbor, N.Y., 1986. Similar methods are used for production of other transgenic animals. A transgenic founder animal can be identified based upon the presence of the transgene in its genome and/or expression of mRNA encoding the transgene in tissues or cells of the animals. A transgenic founder animal can then be used to breed additional animals carrying the transgene. Moreover, transgenic animals carrying the transgene can further be bred to other transgenic animals carrying other transgenes.

[0231] To create an homologous recombinant animal, a vector is prepared which contains at least a portion of a gene encoding a marker protein into which a deletion, addition or substitution has been introduced to thereby alter, e.g., functionally disrupt, the gene. In a preferred embodiment, the vector is designed such that, upon homologous recombination, the endogenous gene is functionally disrupted (i.e., no longer encodes a functional protein; also referred to as a “knock out” vector). Alternatively, the vector can be designed such that, upon homologous recombination, the endogenous gene is mutated or otherwise altered but still encodes functional protein (e.g., the upstream regulatory region can be altered to thereby alter the expression of the endogenous protein). In the homologous recombination vector, the altered portion of the gene is flanked at its 5′ and 3′ ends by additional nucleic acid of the gene to allow for homologous recombination to occur between the exogenous gene carried by the vector and an endogenous gene in an embryonic stem cell. The additional flanking nucleic acid sequences are of sufficient length for successful homologous recombination with the endogenous gene. Typically, several kilobases of flanking DNA (both at the 5′ and 3′ ends) are included in the vector (see, e.g., Thomas and Capecchi, 1987, Cell 51:503 for a description of homologous recombination vectors). The vector is introduced into an embryonic stem cell line (e.g., by electroporation) and cells in which the introduced gene has homologously recombined with the endogenous gene are selected (see, e.g., Li et al., 1992, Cell 69:915). The selected cells are then injected into a blastocyst of an animal (e.g., a mouse) to form aggregation chimeras (see, e.g., Bradley, Teratocarcinomas and Embryonic Stem Cells: A Practical Approach, Robertson, Ed., IRL, Oxford, 1987, pp. 113-152). A chimeric embryo can then be implanted into a suitable pseudopregnant female foster animal and the embryo brought to term. Progeny harboring the homologously recombined DNA in their germ cells can be used to breed animals in which all cells of the animal contain the homologously recombined DNA by germline transmission of the transgene. Methods for constructing homologous recombination vectors and homologous recombinant animals are described further in Bradley (1991) Current Opinion in Bio/Technology 2:823-829 and in PCT Publication NOS. WO 90/11354, WO 91/01140, WO 92/0968, and WO 93/04169.

[0232] In another embodiment, transgenic non-human animals can be produced which contain selected systems which allow for regulated expression of the transgene. One example of such a system is the cre/loxP recombinase system of bacteriophage P1. For a description of the cre/loxP recombinase system, see, e.g., Lakso et al. (1992) Proc. Natl. Acad. Sci. USA 89:6232-6236. Another example of a recombinase system is the FLP recombinase system of Saccharomyces cerevisiae (O'Gorman et al., 1991, Science 251:1351-1355). If a cre/loxP recombinase system is used to regulate expression of the transgene, animals containing transgenes encoding both the Cre recombinase and a selected protein are required. Such animals can be provided through the construction of “double” transgenic animals, e.g., by mating two transgenic animals, one containing a transgene encoding a selected protein and the other containing a transgene encoding a recombinase.

[0233] Clones of the non-human transgenic animals described herein can also be produced according to the methods described in Wilmut et al. (1997) Nature 385:810-813 and PCT Publication NOS. WO 97/07668 and WO 97/07669.

[0234] IV. Pharmaceutical Compositions

[0235] The nucleic acid molecules, polypeptides, and antibodies (also referred to herein as “active compounds”) of the invention can be incorporated into pharmaceutical compositions suitable for administration. Such compositions typically comprise the nucleic acid molecule, protein, or antibody and a pharmaceutically acceptable carrier. As used herein the language “pharmaceutically acceptable carrier” is intended to include any and all solvents, dispersion media, coatings, antibacterial and antifungal agents, isotonic and absorption delaying agents, and the like, compatible with pharmaceutical administration. The use of such media and agents for pharmaceutically active substances is well known in the art. Except insofar as any conventional media or agent is incompatible with the active compound, use thereof in the compositions is contemplated. Supplementary active compounds can also be incorporated into the compositions.

[0236] The invention includes methods for preparing pharmaceutical compositions for modulating the expression or activity of a marker nucleic acid or protein. Such methods comprise formulating a pharmaceutically acceptable carrier with an agent which modulates expression or activity of a marker nucleic acid or protein. Such compositions can further include additional active agents. Thus, the invention further includes methods for preparing a pharmaceutical composition by formulating a pharmaceutically acceptable carrier with an agent which modulates expression or activity of a marker nucleic acid or protein and one or more additional active compounds.

[0237] The invention also provides methods (also referred to herein as “screening assays”) for identifying modulators, i.e., candidate or test compounds or agents (e.g., peptides, peptidomimetics, peptoids, small molecules or other drugs) which (a) bind to the marker, or (b) have a modulatory (e.g., stimulatory or inhibitory) effect on the activity of the marker or, more specifically, (c) have a modulatory effect on the interactions of the marker with one or more of its natural substrates (e.g., peptide, protein, hormone, co-factor, or nucleic acid), or (d) have a modulatory effect on the expression of the marker. Such assays typically comprise a reaction between the marker and one or more assay components. The other components may be either the test compound itself, or a combination of test compound and a natural binding partner of the marker.

[0238] The test compounds of the present invention may be obtained from any available source, including systematic libraries of natural and/or synthetic compounds. Test compounds may also be obtained by any of the numerous approaches in combinatorial library methods known in the art, including: biological libraries; peptoid libraries (libraries of molecules having the functionalities of peptides, but with a novel, non-peptide backbone which are resistant to enzymatic degradation but which nevertheless remain bioactive; see, e.g., Zuckermann et al., 1994, J. Med. Chem. 37:2678-85); spatially addressable parallel solid phase or solution phase libraries; synthetic library methods requiring deconvolution; the ‘one-bead one-compound’ library method; and synthetic library methods using affinity chromatography selection. The biological library and peptoid library approaches are limited to peptide libraries, while the other four approaches are applicable to peptide, non-peptide oligomer or small molecule libraries of compounds (Lam, 1997, Anticancer Drug Des. 12:145).

[0239] Examples of methods for the synthesis of molecular libraries can be found in the art, for example in: DeWitt et al. (1993) Proc. Natl. Acad. Sci. U.S.A. 90:6909; Erb et al. (1994) Proc. Natl. Acad. Sci. USA 91:11422; Zuckermann et al. (1994). J. Med. Chem. 37:2678; Cho et al. (1993) Science 261:1303; Carrell et al. (1994) Angew. Chem. Int. Ed. Engl. 33:2059; Carell et al. (1994) Angew. Chem. Int. Ed. Engl. 33:2061; and in Gallop et al. (1994) J. Med. Chem. 37:1233.

[0240] Libraries of compounds may be presented in solution (e.g., Houghten, 1992, Biotechniques 13:412-421), or on beads (Lam, 1991, Nature 354:82-84), chips (Fodor, 1993, Nature 364:555-556), bacteria and/or spores, (Ladner, U.S. Pat. No. 5,223,409), plasmids (Cull et al, 1992, Proc Natl Acad Sci USA 89:1865-1869) or on phage (Scott and Smith, 1990, Science 249:386-390; Devlin, 1990, Science 249:404-406; Cwirla et al, 1990, Proc. Natl. Acad. Sci. 87:6378-6382; Felici, 1991, J. Mol. Biol. 222:301-310; Ladner, supra.).

[0241] In one embodiment, the invention provides assays for screening candidate or test compounds which are substrates of a protein encoded by or corresponding to a marker or biologically active portion thereof. In another embodiment, the invention provides assays for screening candidate or test compounds which bind to a protein encoded by or corresponding to a marker or biologically active portion thereof. Determining the ability of the test compound to directly bind to a protein can be accomplished, for example, by coupling the compound with a radioisotope or enzymatic label such that binding of the compound to the marker can be determined by detecting the labeled marker compound in a complex. For example, compounds (e.g., marker substrates) can be labeled with 125I, 35S, 14C, or 3H, either directly or indirectly, and the radioisotope detected by direct counting of radioemission or by scintillation counting. Alternatively, assay components can be enzymatically labeled with, for example, horseradish peroxidase, alkaline phosphatase, or luciferase, and the enzymatic label detected by determination of conversion of an appropriate substrate to product.

[0242] In another embodiment, the invention provides assays for screening candidate or test compounds which modulate the expression of a marker or the activity of a protein encoded by or corresponding to a marker, or a biologically active portion thereof. In all likelihood, the protein encoded by or corresponding to the marker can, in vivo, interact with one or more molecules, such as but not limited to, peptides, proteins, hormones, cofactors and nucleic acids. For the purposes of this discussion, such cellular and extracellular molecules are referred to herein as “binding partners” or marker “substrate”.

[0243] One necessary embodiment of the invention in order to facilitate such screening is the use of a protein encoded by or corresponding to marker to identify the protein's natural in vivo binding partners. There are many ways to accomplish this which are known to one skilled in the art. One example is the use of the marker protein as “bait protein” in a two-hybrid assay or three-hybrid assay (see, e.g., U.S. Pat. No. 5,283,317; Zervos et al, 1993, Cell 72:223-232; Madura et al, 1993, J. Biol. Chem. 268:12046-12054; Bartel et al, 1993, Biotechniques 14:920-924; Iwabuchi et al, 1993 Oncogene 8:1693-1696; Brent WO94/10300) in order to identify other proteins which bind to or interact with the marker (binding partners) and, therefore, are possibly involved in the natural function of the marker. Such marker binding partners are also likely to be involved in the propagation of signals by the marker protein or downstream elements of a marker protein-mediated signaling pathway. Alternatively, such marker protein binding partners may also be found to be inhibitors of the marker protein.

[0244] The two-hybrid system is based on the modular nature of most transcription factors, which consist of separable DNA-binding and activation domains. Briefly, the assay utilizes two different DNA constructs. In one construct, the gene that encodes a marker protein fused to a gene encoding the DNA binding domain of a known transcription factor (e.g., GAL-4). In the other construct, a DNA sequence, from a library of DNA sequences, that encodes an unidentified protein (“prey” or “sample”) is fused to a gene that codes for the activation domain of the known transcription factor. If the “bait” and the “prey” proteins are able to interact, in vivo, forming a marker-dependent complex, the DNA-binding and activation domains of the transcription factor are brought into close proximity. This proximity allows transcription of a reporter gene (e.g., LacZ) which is operably linked to a transcriptional regulatory site responsive to the transcription factor. Expression of the reporter gene can be readily detected and cell colonies containing the functional transcription factor can be isolated and used to obtain the cloned gene which encodes the protein which interacts with the marker protein.

[0245] In a further embodiment, assays may be devised through the use of the invention for the purpose of identifying compounds which modulate (e.g., affect either positively or negatively) interactions between a marker protein and its substrates and/or binding partners. Such compounds can include, but are not limited to, molecules such as antibodies, peptides, hormones, oligonucleotides, nucleic acids, and analogs thereof. Such compounds may also be obtained from any available source, including systematic libraries of natural and/or synthetic compounds. The preferred assay components for use in this embodiment is an colon cancer marker protein identified herein, the known binding partner and/or substrate of same, and the test compound. Test compounds can be supplied from any source.

[0246] The basic principle of the assay systems used to identify compounds that interfere with the interaction between the marker protein and its binding partner involves preparing a reaction mixture containing the marker protein and its binding partner under conditions and for a time sufficient to allow the two products to interact and bind, thus forming a complex. In order to test an agent for inhibitory activity, the reaction mixture is prepared in the presence and absence of the test compound. The test compound can be initially included in the reaction mixture, or can be added at a time subsequent to the addition of the marker protein and its binding partner. Control reaction mixtures are incubated without the test compound or with a placebo. The formation of any complexes between the marker protein and its binding partner is then detected. The formation of a complex in the control reaction, but less or no such formation in the reaction mixture containing the test compound, indicates that the compound interferes with the interaction of the marker protein and its binding partner. Conversely, the formation of more complex in the presence of compound than in the control reaction indicates that the compound may enhance interaction of the marker protein and its binding partner.

[0247] The assay for compounds that interfere with the interaction of the marker protein with its binding partner may be conducted in a heterogeneous or homogeneous format. Heterogeneous assays involve anchoring either the marker protein or its binding partner onto a solid phase and detecting complexes anchored to the solid phase at the end of the reaction. In homogeneous assays, the entire reaction is carried out in a liquid phase. In either approach, the order of addition of reactants can be varied to obtain different information about the compounds being tested. For example, test compounds that interfere with the interaction between the marker proteins and the binding partners (e.g., by competition) can be identified by conducting the reaction in the presence of the test substance, i.e., by adding the test substance to the reaction mixture prior to or simultaneously with the marker and its interactive binding partner. Alternatively, test compounds that disrupt preformed complexes, e.g., compounds with higher binding constants that displace one of the components from the complex, can be tested by adding the test compound to the reaction mixture after complexes have been formed. The various formats are briefly described below.

[0248] In a heterogeneous assay system, either the marker protein or its binding partner is anchored onto a solid surface or matrix, while the other corresponding non-anchored component may be labeled, either directly or indirectly. In practice, microtitre plates are often utilized for this approach. The anchored species can be immobilized by a number of methods, either non-covalent or covalent, that are typically well known to one who practices the art. Non-covalent attachment can often be accomplished simply by coating the solid surface with a solution of the marker protein or its binding partner and drying. Alternatively, an immobilized antibody specific for the assay component to be anchored can be used for this purpose. Such surfaces can often be prepared in advance and stored.

[0249] In related embodiments, a fusion protein can be provided which adds a domain that allows one or both of the assay components to be anchored to a matrix. For example, glutathione-S-transferase/marker fusion proteins or glutathione-S-transferase/binding partner can be adsorbed onto glutathione sepharose beads (Sigma Chemical, St. Louis, Mo.) or glutathione derivatized microtiter plates, which are then combined with the test compound or the test compound and either the non-adsorbed marker or its binding partner, and the mixture incubated under conditions conducive to complex formation (e.g., physiological conditions). Following incubation, the beads or microtiter plate wells are washed to remove any unbound assay components, the immobilized complex assessed either directly or indirectly, for example, as described above. Alternatively, the complexes can be dissociated from the matrix, and the level of marker binding or activity determined using standard techniques.

[0250] Other techniques for immobilizing proteins on matrices can also be used in the screening assays of the invention. For example, either a marker protein or a marker protein binding partner can be immobilized utilizing conjugation of biotin and streptavidin. Biotinylated marker protein or target molecules can be prepared from biotin-NHS (N-hydroxy-succinimide) using techniques known in the art (e.g., biotinylation kit, Pierce Chemicals, Rockford, Ill.), and immobilized in the wells of streptavidin-coated 96 well plates (Pierce Chemical). In certain embodiments, the protein-immobilized surfaces can be prepared in advance and stored.

[0251] In order to conduct the assay, the corresponding partner of the immobilized assay component is exposed to the coated surface with or without the test compound. After the reaction is complete, unreacted assay components are removed (e.g., by washing) and any complexes formed will remain immobilized on the solid surface. The detection of complexes anchored on the solid surface can be accomplished in a number of ways. Where the non-immobilized component is pre-labeled, the detection of label immobilized on the surface indicates that complexes were formed. Where the non-immobilized component is not pre-labeled, an indirect label can be used to detect complexes anchored on the surface; e.g., using a labeled antibody specific for the initially non-immobilized species (the antibody, in turn, can be directly labeled or indirectly labeled with, e.g., a labeled anti-Ig antibody). Depending upon the order of addition of reaction components, test compounds which modulate (inhibit or enhance) complex formation or which disrupt preformed complexes can be detected.

[0252] In an alternate embodiment of the invention, a homogeneous assay may be used. This is typically a reaction, analogous to those mentioned above, which is conducted in a liquid phase in the presence or absence of the test compound. The formed complexes are then separated from unreacted components, and the amount of complex formed is determined. As mentioned for heterogeneous assay systems, the order of addition of reactants to the liquid phase can yield information about which test compounds modulate (inhibit or enhance) complex formation and which disrupt preformed complexes.

[0253] In such a homogeneous assay, the reaction products may be separated from unreacted assay components by any of a number of standard techniques, including but not limited to: differential centrifugation, chromatography, electrophoresis and immunoprecipitation. In differential centrifugation, complexes of molecules may be separated from uncomplexed molecules through a series of centrifugal steps, due to the different sedimentation equilibria of complexes based on their different sizes and densities (see, for example, Rivas, G., and Minton, A. P., Trends Biochem Sci 1993 August;18(8):284-7). Standard chromatographic techniques may also be utilized to separate complexed molecules from uncomplexed ones. For example, gel filtration chromatography separates molecules based on size, and through the utilization of an appropriate gel filtration resin in a column format, for example, the relatively larger complex may be separated from the relatively smaller uncomplexed components. Similarly, the relatively different charge properties of the complex as compared to the uncomplexed molecules may be exploited to differentially separate the complex from the remaining individual reactants, for example through the use of ion-exchange chromatography resins. Such resins and chromatographic techniques are well known to one skilled in the art (see, e.g., Heegaard, 1998, J. Mol. Recognit. 11:141-148; Hage and Tweed, 1997, J. Chromatogr. B. Biomed. Sci. Appl., 699:499-525). Gel electrophoresis may also be employed to separate complexed molecules from unbound species (see, e.g., Ausubel et al (eds.), In: Current Protocols in Molecular Biology, J. Wiley & Sons, New York. 1999). In this technique, protein or nucleic acid complexes are separated based on size or charge, for example. In order to maintain the binding interaction during the electrophoretic process, nondenaturing gels in the absence of reducing agent are typically preferred, but conditions appropriate to the particular interactants will be well known to one skilled in the art. Immunoprecipitation is another common technique utilized for the isolation of a protein-protein complex from solution (see, e.g., Ausubel et al (eds.), In: Current Protocols in Molecular Biology, J. Wiley & Sons, New York. 1999). In this technique, all proteins binding to an antibody specific to one of the binding molecules are precipitated from solution by conjugating the antibody to a polymer bead that may be readily collected by centrifugation. The bound assay components are released from the beads (through a specific proteolysis event or other technique well known in the art which will not disturb the protein-protein interaction in the complex), and a second immunoprecipitation step is performed, this time utilizing antibodies specific for the correspondingly different interacting assay component. In this manner, only formed complexes should remain attached to the beads. Variations in complex formation in both the presence and the absence of a test compound can be compared, thus offering information about the ability of the compound to modulate interactions between the marker protein and its binding partner.

[0254] Also within the scope of the present invention are methods for direct detection of interactions between the marker protein and its natural binding partner and/or a test compound in a homogeneous or heterogeneous assay system without further sample manipulation. For example, the technique of fluorescence energy transfer may be utilized (see, e.g., Lakowicz et al, U.S. Pat. No. 5,631,169; Stavrianopoulos et al, U.S. Pat. No. 4,868,103). Generally, this technique involves the addition of a fluorophore label on a first ‘donor’ molecule (e.g., marker or test compound) such that its emitted fluorescent energy will be absorbed by a fluorescent label on a second, ‘acceptor’ molecule (e.g., marker or test compound), which in turn is able to fluoresce due to the absorbed energy. Alternately, the ‘donor’ protein molecule may simply utilize the natural fluorescent energy of tryptophan residues. Labels are chosen that emit different wavelengths of light, such that the ‘acceptor’ molecule label may be differentiated from that of the ‘donor’. Since the efficiency of energy transfer between the labels is related to the distance separating the molecules, spatial relationships between the molecules can be assessed. In a situation in which binding occurs between the molecules, the fluorescent emission of the ‘acceptor’ molecule label in the assay should be maximal. An FET binding event can be conveniently measured through standard fluorometric detection means well known in the art (e.g., using a fluorimeter). A test substance which either enhances or hinders participation of one of the species in the preformed complex will result in the generation of a signal variant to that of background. In this way, test substances that modulate interactions between a marker and its binding partner can be identified in controlled assays.

[0255] In another embodiment, modulators of marker expression are identified in a method wherein a cell is contacted with a candidate compound and the expression of marker mRNA or protein in the cell, is determined. The level of expression of marker mRNA or protein in the presence of the candidate compound is compared to the level of expression of marker mRNA or protein in the absence of the candidate compound. The candidate compound can then be identified as a modulator of marker expression based on this comparison. For example, when expression of marker mRNA or protein is greater (statistically significantly greater) in the presence of the candidate compound than in its absence, the candidate compound is identified as a stimulator of marker mRNA or protein expression. Conversely, when expression of marker mRNA or protein is less (statistically significantly less) in the presence of the candidate compound than in its absence, the candidate compound is identified as an inhibitor of marker mRNA or protein expression. The level of marker mRNA or protein expression in the cells can be determined by methods described herein for detecting marker mRNA or protein.

[0256] In another aspect, the invention pertains to a combination of two or more of the assays described herein. For example, a modulating agent can be identified using a cell-based or a cell free assay, and the ability of the agent to modulate the activity of a marker protein can be further confirmed in vivo, e.g., in a whole animal model for cellular transformation and/or tumorigenesis.

[0257] This invention further pertains to novel agents identified by the above-described screening assays. Accordingly, it is within the scope of this invention to further use an agent identified as described herein in an appropriate animal model. For example, an agent identified as described herein (e.g., an marker modulating agent, an antisense marker nucleic acid molecule, an marker-specific antibody, or an marker-binding partner) can be used in an animal model to determine the efficacy, toxicity, or side effects of treatment with such an agent. Alternatively, an agent identified as described herein can be used in an animal model to determine the mechanism of action of such an agent. Furthermore, this invention pertains to uses of novel agents identified by the above-described screening assays for treatments as described herein.

[0258] It is understood that appropriate doses of small molecule agents and protein or polypeptide agents depends upon a number of factors within the knowledge of the ordinarily skilled physician, veterinarian, or researcher. The dose(s) of these agents will vary, for example, depending upon the identity, size, and condition of the subject or sample being treated, further depending upon the route by which the composition is to be administered, if applicable, and the effect which the practitioner desires the agent to have upon the nucleic acid or polypeptide of the invention. Exemplary doses of a small molecule include milligram or microgram amounts per kilogram of subject or sample weight (e.g. about 1 microgram per kilogram to about 500 milligrams per kilogram, about 100 micrograms per kilogram to about 5 milligrams per kilogram, or about 1 microgram per kilogram to about 50 micrograms per kilogram). Exemplary doses of a protein or polypeptide include gram, milligram or microgram amounts per kilogram of subject or sample weight (e.g. about 1 microgram per kilogram to about 5 grams per kilogram, about 100 micrograms per kilogram to about 500 milligrams per kilogram, or about 1 milligram per kilogram to about 50 milligrams per kilogram). It is furthermore understood that appropriate doses of one of these agents depend upon the potency of the agent with respect to the expression or activity to be modulated. Such appropriate doses can be determined using the assays described herein. When one or more of these agents is to be administered to an animal (e.g. a human) in order to modulate expression or activity of a polypeptide or nucleic acid of the invention, a physician, veterinarian, or researcher can, for example, prescribe a relatively low dose at first, subsequently increasing the dose until an appropriate response is obtained. In addition, it is understood that the specific dose level for any particular animal subject will depend upon avariety of factors including the activity of the specific agent employed, the age, body weight, general health, gender, and diet of the subject, the time of administration, the route of administration, the rate of excretion, any drug combination, and the degree of expression or activity to be modulated.

[0259] A pharmaceutical composition of the invention is formulated to be compatible with its intended route of administration. Examples of routes of administration include parenteral, e.g., intravenous, intradermal, subcutaneous, oral (e.g., inhalation), transdermal (topical), transmucosal, and rectal administration. Solutions or suspensions used for parenteral, intradermal, or subcutaneous application can include the following components: a sterile diluent such as water for injection, saline solution, fixed oils, polyethylene glycols, glycerine, propylene glycol or other synthetic solvents; antibacterial agents such as benzyl alcohol or methyl parabens; antioxidants such as ascorbic acid or sodium bisulfite; chelating agents such as ethylenediamine-tetraacetic acid; buffers such as acetates, citrates or phosphates and agents for the adjustment of tonicity such as sodium chloride or dextrose. pH can be adjusted with acids or bases, such as hydrochloric acid or sodium hydroxide. The parenteral preparation can be enclosed in ampules, disposable syringes or multiple dose vials made of glass or plastic.

[0260] Pharmaceutical compositions suitable for injectable use include sterile aqueous solutions (where water soluble) or dispersions and sterile powders for the extemporaneous preparation of sterile injectable solutions or dispersions. For intravenous administration, suitable carriers include physiological saline, bacteriostatic water, Cremophor EL (BASF; Parsippany, NJ) or phosphate buffered saline (PBS). In all cases, the composition must be sterile and should be fluid to the extent that easy syringability exists. It must be stable under the conditions of manufacture and storage and must be preserved against the contaminating action of microorganisms such as bacteria and fungi. The carrier can be a solvent or dispersion medium containing, for example, water, ethanol, polyol (for example, glycerol, propylene glycol, and liquid polyethylene glycol, and the like), and suitable mixtures thereof. The proper fluidity can be maintained, for example, by the use of a coating such as lecithin, by the maintenance of the required particle size in the case of dispersion and by the use of surfactants. Prevention of the action of microorganisms can be achieved by various antibacterial and antifungal agents, for example, parabens, chlorobutanol, phenol, ascorbic acid, thimerosal, and the like. In many cases, it will be preferable to include isotonic agents, for example, sugars, polyalcohols such as mannitol, sorbitol, or sodium chloride in the composition. Prolonged absorption of the injectable compositions can be brought about by including in the composition an agent which delays absorption, for example, aluminum monostearate and gelatin.

[0261] Sterile injectable solutions can be prepared by incorporating the active compound (e.g., a polypeptide or antibody) in the required amount in an appropriate solvent with one or a combination of ingredients enumerated above, as required, followed by filtered sterilization. Generally, dispersions are prepared by incorporating the active compound into a sterile vehicle which contains a basic dispersion medium, and then incorporating the required other ingredients from those enumerated above. In the case of sterile powders for the preparation of sterile injectable solutions, the preferred methods of preparation are vacuum drying and freeze-drying which yields a powder of the active ingredient plus any additional desired ingredient from a previously sterile-filtered solution thereof.

[0262] Oral compositions generally include an inert diluent or an edible carrier. They can be enclosed in gelatin capsules or compressed into tablets. For the purpose of oral therapeutic administration, the active compound can be incorporated with excipients and used in the form of tablets, troches, or capsules. Oral compositions can also be prepared using a fluid carrier for use as a mouthwash, wherein the compound in the fluid carrier is applied orally and swished and expectorated or swallowed.

[0263] Pharmaceutically compatible binding agents, and/or adjuvant materials can be included as part of the composition. The tablets, pills, capsules, troches, and the like can contain any of the following ingredients, or compounds of a similar nature: a binder such as microcrystalline cellulose, gum tragacanth or gelatin; an excipient such as starch or lactose, a disintegrating agent such as alginic acid, Primogel, or corn starch; a lubricant such as magnesium stearate or Sterotes; a glidant such as colloidal silicon dioxide; a sweetening agent such as sucrose or saccharin; or a flavoring agent such as peppermint, methyl salicylate, or orange flavoring.

[0264] For administration by inhalation, the compounds are delivered in the form of an aerosol spray from a pressurized container or dispenser which contains a suitable propellant, e.g., a gas such as carbon dioxide, or a nebulizer.

[0265] Systemic administration can also be by transmucosal or transdermal means. For transmucosal or transdermal administration, penetrants appropriate to the barrier to be permeated are used in the formulation. Such penetrants are generally known in the art, and include, for example, for transmucosal administration, detergents, bile salts, and fusidic acid derivatives. Transmucosal administration can be accomplished through the use of nasal sprays or suppositories. For transdermal administration, the active compounds are formulated into ointments, salves, gels, or creams as generally known in the art.

[0266] The compounds can also be prepared in the form of suppositories (e.g., with conventional suppository bases such as cocoa butter and other glycerides) or retention enemas for rectal delivery.

[0267] In one embodiment, the active compounds are prepared with carriers that will protect the compound against rapid elimination from the body, such as a controlled release formulation, including implants and microencapsulated delivery systems. Biodegradable, biocompatible polymers can be used, such as ethylene vinyl acetate, polyanhydrides, polyglycolic acid, collagen, polyorthoesters, and polylactic acid. Methods for preparation of such formulations will be apparent to those skilled in the art. The materials can also be obtained commercially from Alza Corporation and Nova Pharmaceuticals, Inc. Liposomal suspensions (including liposomes having monoclonal antibodies incorporated therein or thereon) can also be used as pharmaceutically acceptable carriers. These can be prepared according to methods known to those skilled in the art, for example, as described in U.S. Pat. No. 4,522,811.

[0268] It is especially advantageous to formulate oral or parenteral compositions in dosage unit form for ease of administration and uniformity of dosage. Dosage unit form as used herein refers to physically discrete units suited as unitary dosages for the subject to be treated; each unit containing a predetermined quantity of active compound calculated to produce the desired therapeutic effect in association with the required pharmaceutical carrier. The specification for the dosage unit forms of the invention are dictated by and directly dependent on the unique characteristics of the active compound and the particular therapeutic effect to be achieved, and the limitations inherent in the art of compounding such an active compound for the treatment of individuals.

[0269] For antibodies, the preferred dosage is 0.1 mg/kg to 100 mg/kg of body weight (generally 10 mg/kg to 20 mg/kg). If the antibody is to act in the brain, a dosage of 50 mg/kg to 100 mg/kg is usually appropriate. Generally, partially human antibodies and fully human antibodies have a longer half-life within the human body than other antibodies. Accordingly, lower dosages and less frequent administration is often possible. Modifications such as lipidation can be used to stabilize antibodies and to enhance uptake and tissue penetration (e.g., into the colon epithelium). A method for lipidation of antibodies is described by Cruikshank et al. (1997) J. Acquired Immune Deficiency Syndromes and Human Retrovirology 14:193.

[0270] The invention also provides vaccine compositions for the prevention and/or treatment of colon cancer. The invention provides colon cancer vaccine compositions in which a protein of a marker of Tables 1 and 2, or a combination of proteins of the markers of Tables 1 and 2, are introduced into a subject in order to stimulate an immune response against the colon cancer. The invention also provides colon cancer vaccine compositions in which a gene expression construct, which expresses a marker or fragment of a marker identified in Tables 1 and 2, is introduced into the subject such that a protein or fragment of a protein encoded by a marker of Tables 1 and 2 is produced by transfected cells in the subject at a higher than normal level and elicits an immune response.

[0271] In one embodiment, a colon cancer vaccine is provided and employed as an immunotherapeutic agent for the prevention of colon cancer. In another embodiment, a colon cancer vaccine is provided and employed as an immunotherapeutic agent for the treatment of colon cancer.

[0272] By way of example, a colon cancer vaccine comprised of the proteins of the markers of Tables 1 and 2, may be employed for the prevention and/or treatment of colon cancer in a subject by administering the vaccine by a variety of routes, e.g., intradermially, subcutaneously, or intramuscularly. In addition, the colon cancer vaccine can be administered together with adjuvants and/or immunomodulators to boost the activity of the vaccine and the subject's response. In one embodiment, devices and/or compositions containing the vaccine, suitable for sustained or intermittent release could be, implanted in the body or topically applied thereto for the relatively slow release of such materials into the body. The colon cancer vaccine can be introduced along with immunomodulatory compounds, which can alter the type of immune response produced in order to produce a response which will be more effective in eliminating the cancer.

[0273] In another embodiment, a colon cancer vaccine comprised of an expression construct of the markers of Tables 1 and 2, may be introduced by injection into muscle or by coating onto microprojectiles and using a device designed for the purpose to fire the projectiles at high speed into the skin. The cells of the subject will then express the protein(s) or fragments of proteins of the markers of Tables 1 and 2 and induce an immune response. In addition, the colon cancer vaccine may be introduced along with expression constructs for immunomodulatory molecules, such as cytokines, which may increase the immune response or modulate the type of immune response produced in order to produce a response which will be more effective in eliminating the cancer.

[0274] The marker nucleic acid molecules can be inserted into vectors and used as gene therapy vectors. Gene therapy vectors can be delivered to a subject by, for example, intravenous injection, local administration (U.S. Pat. No. 5,328,470), or by stereotactic injection (see, e.g., Chen et al., 1994, Proc. Natl. Acad. Sci. USA 91:3054-3057). The pharmaceutical preparation of the gene therapy vector can include the gene therapy vector in an acceptable diluent, or can comprise a slow release matrix in which the gene delivery vehicle is imbedded. Alternatively, where the complete gene delivery vector can be produced intact from recombinant cells, e.g. retroviral vectors, the pharmaceutical preparation can include one or more cells which produce the gene delivery system.

[0275] The pharmaceutical compositions can be included in a container, pack, or dispenser together with instructions for administration.

[0276] V. Predictive Medicine

[0277] The present invention pertains to the field of predictive medicine in which diagnostic assays, prognostic assays, pharmacogenomics, and monitoring clinical trails are used for prognostic (predictive) purposes to thereby treat an individual prophylactically. Accordingly, one aspect of the present invention relates to diagnostic assays for determining the level of expression of one or more marker proteins or nucleic acids, in order to determine whether an individual is at risk of developing colon cancer. Such assays can be used for prognostic or predictive purposes to thereby prophylactically treat an individual prior to the onset of the cancer.

[0278] Yet another aspect of the invention pertains to monitoring the influence of agents (e.g., drugs or other compounds administered either to inhibit colon cancer or to treat or prevent any other disorder {i.e. in order to understand any colon carcinogenic effects that such treatment may have}) on the expression or activity of a marker of the invention in clinical trials. These and other agents are described in further detail in the following sections.

[0279] A. Diagnostic Assays

[0280] An exemplary method for detecting the presence or absence of a marker protein or nucleic acid in a biological sample involves obtaining a biological sample (e.g. a colon-associated body fluid) from a test subject and contacting the biological sample with a compound or an agent capable of detecting the polypeptide or nucleic acid (e.g., mRNA, genomic DNA, or cDNA). The detection methods of the invention can thus be used to detect mRNA, protein, cDNA, or genomic DNA, for example, in a biological sample in vitro as well as in vivo. For example, in vitro techniques for detection of mRNA include Northern hybridizations and in situ hybridizations. In vitro techniques for detection of a marker protein include enzyme linked immunosorbent assays (ELISAs), Western blots, immunoprecipitations and immunofluorescence. In vitro techniques for detection of genomic DNA include Southern hybridizations. Furthermore, in vivo techniques for detection of a marker protein include introducing into a subject a labeled antibody directed against the protein or fragment thereof. For example, the antibody can be labeled with a radioactive marker whose presence and location in a subject can be detected by standard imaging techniques.

[0281] A general principle of such diagnostic and prognostic assays involves preparing a sample or reaction mixture that may contain a marker, and a probe, under appropriate conditions and for a time sufficient to allow the marker and probe to interact and bind, thus forming a complex that can be removed and/or detected in the reaction mixture. These assays can be conducted in a variety of ways.

[0282] For example, one method to conduct such an assay would involve anchoring the marker or probe onto a solid phase support, also referred to as a substrate, and detecting target marker/probe complexes anchored on the solid phase at the end of the reaction. In one embodiment of such a method, a sample from a subject, which is to be assayed for presence and/or concentration of marker, can be anchored onto a carrier or solid phase support. In another embodiment, the reverse situation is possible, in which the probe can be anchored to a solid phase and a sample from a subject can be allowed to react as an unanchored component of the assay.

[0283] There are many established methods for anchoring assay components to a solid phase. These include, without limitation, marker or probe molecules which are immobilized through conjugation of biotin and streptavidin. Such biotinylated assay components can be prepared from biotin-NHS(N-hydroxy-succinimide) using techniques known in the art (e.g., biotinylation kit, Pierce Chemicals, Rockford, Ill.), and immobilized in the wells of streptavidin-coated 96 well plates (Pierce Chemical). In certain embodiments, the surfaces with immobilized assay components can be prepared in advance and stored.

[0284] Other suitable carriers or solid phase supports for such assays include any material capable of binding the class of molecule to which the marker or probe belongs. Well-known supports or carriers include, but are not limited to, glass, polystyrene, nylon, polypropylene, nylon, polyethylene, dextran, amylases, natural and modified celluloses, polyacrylamides, gabbros, and magnetite.

[0285] In order to conduct assays with the above mentioned approaches, the non-immobilized component is added to the solid phase upon which the second component is anchored. After the reaction is complete, uncomplexed components may be removed (e.g., by washing) under conditions such that any complexes formed will remain immobilized upon the solid phase. The detection of marker/probe complexes anchored to the solid phase can be accomplished in a number of methods outlined herein.

[0286] In a preferred embodiment, the probe, when it is the unanchored assay component, can be labeled for the purpose of detection and readout of the assay, either directly or indirectly, with detectable labels discussed herein and which are well-known to one skilled in the art.

[0287] It is also possible to directly detect marker/probe complex formation without further manipulation or labeling of either component (marker or probe), for example by utilizing the technique of fluorescence energy transfer (see, for example, Lakowicz et al., U.S. Pat. No. 5,631,169; Stavrianopoulos, et al., U.S. Pat. No. 4,868,103). A fluorophore label on the first, ‘donor’ molecule is selected such that, upon excitation with incident light of appropriate wavelength, its emitted fluorescent energy will be absorbed by a fluorescent label on a second ‘acceptor’ molecule, which in turn is able to fluoresce due to the absorbed energy. Alternately, the ‘donor’ protein molecule may simply utilize the natural fluorescent energy of tryptophan residues. Labels are chosen that emit different wavelengths of light, such that the ‘acceptor’ molecule label may be differentiated from that of the ‘donor’. Since the efficiency of energy transfer between the labels is related to the distance separating the molecules, spatial relationships between the molecules can be assessed. In a situation in which binding occurs between the molecules, the fluorescent emission of the ‘acceptor’ molecule label in the assay should be maximal. An FET binding event can be conveniently measured through standard fluorometric detection means well known in the art (e.g., using a fluorimeter).

[0288] In another embodiment, determination of the ability of a probe to recognize a marker can be accomplished without labeling either assay component (probe or marker) by utilizing a technology such as real-time Biomolecular Interaction Analysis (BIA) (see, e.g., Sjolander, S. and Urbaniczky, C., 1991, Anal. Chem. 63:2338-2345 and Szabo et al., 1995, Curr. Opin. Struct. Biol. 5:699-705). As used herein, “BIA” or “surface plasmon resonance” is a technology for studying biospecific interactions in real time, without labeling any of the interactants (e.g., BIAcore). Changes in the mass at the binding surface (indicative of a binding event) result in alterations of the refractive index of light near the surface (the optical phenomenon of surface plasmon resonance (SPR)), resulting in a detectable signal which can be used as an indication of real-time reactions between biological molecules.

[0289] Alternatively, in another embodiment, analogous diagnostic and prognostic assays can be conducted with marker and probe as solutes in a liquid phase. In such an assay, the complexed marker and probe are separated from uncomplexed components by any of a number of standard techniques, including but not limited to: differential centrifugation, chromatography, electrophoresis and immunoprecipitation. In differential centrifugation, marker/probe complexes may be separated from uncomplexed assay components through a series of centrifugal steps, due to the different sedimentation equilibria of complexes based on their different sizes and densities (see, for example, Rivas, G., and Minton, A. P., 1993, Trends Biochem Sci. 18(8):284-7). Standard chromatographic techniques may also be utilized to separate complexed molecules from uncomplexed ones. For example, gel filtration chromatography separates molecules based on size, and through the utilization of an appropriate gel filtration resin in a column format, for example, the relatively larger complex may be separated from the relatively smaller uncomplexed components. Similarly, the relatively different charge properties of the marker/probe complex as compared to the uncomplexed components may be exploited to differentiate the complex from uncomplexed components, for example through the utilization of ion-exchange chromatography resins. Such resins and chromatographic techniques are well known to one skilled in the art (see, e.g., Heegaard, N. H., 1998, J. Mol Recognit. Winter 11(1-6):141-8; Hage, D. S., and Tweed, S. A. J. Chromatogr B Biomed Sci Appl October 10, 1997;699(1-2):499-525). Gel electrophoresis may also be employed to separate complexed assay components from unbound components (see, e.g., Ausubel et al., ed., Current Protocols in Molecular Biology, John Wiley & Sons, New York, 1987-1999). In this technique, protein or nucleic acid complexes are separated based on size or charge, for example. In order to maintain the binding interaction during the electrophoretic process, non-denaturing gel matrix materials and conditions in the absence of reducing agent are typically preferred. Appropriate conditions to the particular assay and components thereof will be well known to one skilled in the art.

[0290] In a particular embodiment, the level of marker mRNA can be determined both by in situ and by in vitro formats in a biological sample using methods known in the art. The term “biological sample” is intended to include tissues, cells, biological fluids and isolates thereof, isolated from a subject, as well as tissues, cells and fluids present within a subject. Many expression detection methods use isolated RNA. For in vitro methods, any RNA isolation technique that does not select against the isolation of mRNA can be utilized for the purification of RNA from colon cells (see, e.g., Ausubel et al., ed., Current Protocols in Molecular Biology, John Wiley & Sons, New York 1987-1999). Additionally, large numbers of tissue samples can readily be processed using techniques well known to those of skill in the art, such as, for example, the single-step RNA isolation process of Chomczynski (1989, U.S. Pat. No. 4,843,155).

[0291] The isolated mRNA can be used in hybridization or amplification assays that include, but are not limited to, Southern or Northern analyses, polymerase chain reaction analyses and probe arrays. One preferred diagnostic method for the detection of mRNA levels involves contacting the isolated mRNA with a nucleic acid molecule (probe) that can hybridize to the mRNA encoded by the gene being detected. The nucleic acid probe can be, for example, a full-length cDNA, or a portion thereof, such as an oligonucleotide of at least 7, 15, 30, 50, 100, 250 or 500 nucleotides in length and sufficient to specifically hybridize under stringent conditions to a mRNA or genomic DNA encoding a marker of the present invention. Other suitable probes for use in the diagnostic assays of the invention are described herein. Hybridization of an mRNA with the probe indicates that the marker in question is being expressed.

[0292] In one format, the mRNA is immobilized on a solid surface and contacted with a probe, for example by running the isolated mRNA on an agarose gel and transferring the mRNA from the gel to a membrane, such as nitrocellulose. In an alternative format, the probe(s) are immobilized on a solid surface and the mRNA is contacted with the probe(s), for example, in an Affymetrix gene chip array. A skilled artisan can readily adapt known mRNA detection methods for use in detecting the level of mRNA encoded by the markers of the present invention.

[0293] An alternative method for determining the level of mRNA marker in a sample involves the process of nucleic acid amplification, e.g., by rtPCR (the experimental embodiment set forth in Mullis, 1987, U.S. Pat. No. 4,683,202), ligase chain reaction (Barany, 1991, Proc. Natl. Acad. Sci. USA, 88:189-193), self sustained sequence replication (Guatelli et al., 1990, Proc. Natl. Acad. Sci. USA 87:1874-1878), transcriptional amplification system (Kwoh et al., 1989, Proc. Natl. Acad. Sci. USA 86:1173-1177), Q-Beta Replicase (Lizardi et al., 1988, Bio/Technology 6:1197), rolling circle replication (Lizardi et al., U.S. Pat. No. 5,854,033) or any other nucleic acid amplification method, followed by the detection of the amplified molecules using techniques well known to those of skill in the art. These detection schemes are especially useful for the detection of nucleic acid molecules if such molecules are present in very low numbers. As used herein, amplification primers are defined as being a pair of nucleic acid molecules that can anneal to 5′ or 3′ regions of a gene (plus and minus strands, respectively, or vice-versa) and contain a short region in between. In general, amplification primers are from about 10 to 30 nucleotides in length and flank a region from about 50 to 200 nucleotides in length. Under appropriate conditions and with appropriate reagents, such primers permit the amplification of a nucleic acid molecule comprising the nucleotide sequence flanked by the primers.

[0294] For in situ methods, mRNA does not need to be isolated from the colon cells prior to detection. In such methods, a cell or tissue sample is prepared/processed using known histological methods. The sample is then immobilized on a support, typically a glass slide, and then contacted with a probe that can hybridize to mRNA that encodes the marker.

[0295] As an alternative to making determinations based on the absolute expression level of the marker, determinations may be based on the normalized expression level of the marker. Expression levels are normalized by correcting the absolute expression level of a marker by comparing its expression to the expression of a gene that is not a marker, e.g., a housekeeping gene that is constitutively expressed. Suitable genes for normalization include housekeeping genes such as the actin gene, or epithelial cell-specific genes. This normalization allows the comparison of the expression level in one sample, e.g., a patient sample, to another sample, e.g., a non-colon cancer sample, or between samples from different sources.

[0296] Alternatively, the expression level can be provided as a relative expression level. To determine a relative expression level of a marker, the level of expression of the marker is determined for 10 or more samples of normal versus cancer cell isolates, preferably 50 or more samples, prior to the determination of the expression level for the sample in question. The mean expression level of each of the genes assayed in the larger number of samples is determined and this is used as a baseline expression level for the marker. The expression level of the marker determined for the test sample (absolute level of expression) is then divided by the mean expression value obtained for that marker. This provides a relative expression level.

[0297] Preferably, the samples used in the baseline determination will be from colon cancer or from non-colon cancer cells of colon tissue. The choice of the cell source is dependent on the use of the relative expression level. Using expression found in normal tissues as a mean expression score aids in validating whether the marker assayed is colon specific (versus normal cells). In addition, as more data is accumulated, the mean expression value can be revised, providing improved relative expression values based on accumulated data. Expression data from colon cells provides a means for grading the severity of the colon cancer state.

[0298] In another embodiment of the present invention, a marker protein is detected. A preferred agent for detecting marker protein of the invention is an antibody capable of binding to such a protein or a fragment thereof, preferably an antibody with a detectable label. Antibodies can be polyclonal, or more preferably, monoclonal. An intact antibody, or a fragment or derivative thereof (e.g., Fab or F(ab′)2) can be used. The term “labeled”, with regard to the probe or antibody, is intended to encompass direct labeling of the probe or antibody by coupling (i.e., physically linking) a detectable substance to the probe or antibody, as well as indirect labeling of the probe or antibody by reactivity with another reagent that is directly labeled. Examples of indirect labeling include detection of a primary antibody using a fluorescently labeled secondary antibody and end-labeling of a DNA probe with biotin such that it can be detected with fluorescently labeled streptavidin.

[0299] Proteins from colon cells can be isolated using techniques that are well known to those of skill in the art. The protein isolation methods employed can, for example, be such as those described in Harlow and Lane (Harlow and Lane, 1988, Antibodies: A Laboratory Manual, Cold Spring Harbor Laboratory Press, Cold Spring Harbor, N.Y.).

[0300] A variety of formats can be employed to determine whether a sample contains a protein that binds to a given antibody. Examples of such formats include, but are not limited to, enzyme immunoassay (EIA), radioimmunoassay (RIA), Western blot analysis and enzyme linked immunoabsorbant assay (ELISA). A skilled artisan can readily adapt known protein/antibody detection methods for use in determining whether colon cells express a marker of the present invention.

[0301] In one format, antibodies, or antibody fragments or derivatives, can be used in methods such as Western blots or immunofluorescence techniques to detect the expressed proteins. In such uses, it is generally preferable to immobilize either the antibody or proteins on a solid support. Suitable solid phase supports or carriers include any support capable of binding an antigen or an antibody. Well-known supports or carriers include glass, polystyrene, polypropylene, polyethylene, dextran, nylon, amylases, natural and modified celluloses, polyacrylamides, gabbros, and magnetite.

[0302] One skilled in the art will know many other suitable carriers for binding antibody or antigen, and will be able to adapt such support for use with the present invention. For example, protein isolated from colon cells can be run on a polyacrylamide gel electrophoresis and immobilized onto a solid phase support such as nitrocellulose. The support can then be washed with suitable buffers followed by treatment with the detectably labeled antibody. The solid phase support can then be washed with the buffer a second time to remove unbound antibody. The amount of bound label on the solid support can then be detected by conventional means.

[0303] The invention also encompasses kits for detecting the presence of a marker protein or nucleic acid in a biological sample (e.g. a colon-associated body fluid such as a urine sample). Such kits can be used to determine if a subject is suffering from or is at increased risk of developing colon cancer. For example, the kit can comprise a labeled compound or agent capable of detecting a marker protein or nucleic acid in a biological sample and means for determining the amount of the protein or mRNA in the sample (e.g., an antibody which binds the protein or a fragment thereof, or an oligonucleotide probe which binds to DNA or mRNA encoding the protein). Kits can also include instructions for interpreting the results obtained using the kit.

[0304] For antibody-based kits, the kit can comprise, for example: (1) a first antibody (e.g., attached to a solid support) which binds to a marker protein; and, optionally, (2) a second, different antibody which binds to either the protein or the first antibody and is conjugated to a detectable label.

[0305] For oligonucleotide-based kits, the kit can comprise, for example: (1) an oligonucleotide, e.g., a detectably labeled oligonucleotide, which hybridizes to a nucleic acid sequence encoding a marker protein or (2) a pair of primers useful for amplifying a marker nucleic acid molecule. The kit can also comprise, e.g., a buffering agent, a preservative, or a protein stabilizing agent. The kit can further comprise components necessary for detecting the detectable label (e.g., an enzyme or a substrate). The kit can also contain a control sample or a series of control samples which can be assayed and compared to the test sample. Each component of the kit can be enclosed within an individual container and all of the various containers can be within a single package, along with instructions for interpreting the results of the assays performed using the kit.

[0306] B. Pharmacogenomics

[0307] The markers of the invention are also useful as pharmacogenomic markers. As used herein, a “pharmacogenomic marker” is an objective biochemical marker whose expression level correlates with a specific clinical drug response or susceptibility in a patient (see, e.g., McLeod et al. (1999) Eur. J. Cancer 35(12): 1650-1652). The presence or quantity of the pharmacogenomic marker expression is related to the predicted response of the patient and more particularly the patient's tumor to therapy with a specific drug or class of drugs. By assessing the presence or quantity of the expression of one or more pharmacogenomic markers in a patient, a drug therapy which is most appropriate for the patient, or which is predicted to have a greater degree of success, may be selected. For example, based on the presence or quantity of RNA or protein encoded by specific tumor markers in a patient, a drug or course of treatment may be selected that is optimized for the treatment of the specific tumor likely to be present in the patient. The use of pharmacogenomic markers therefore permits selecting or designing the most appropriate treatment for each cancer patient without trying different drugs or regimes.

[0308] Another aspect of pharmacogenomics deals with genetic conditions that alters the way the body acts on drugs. These pharmacogenetic conditions can occur either as rare defects or as polymorphisms. For example, glucose-6-phosphate dehydrogenase (G6PD) deficiency is a common inherited enzymopathy in which the main clinical complication is hemolysis after ingestion of oxidant drugs (anti-malarials, sulfonamides, analgesics, nitrofurans) and consumption of fava beans.

[0309] As an illustrative embodiment, the activity of drug metabolizing enzymes is a major determinant of both the intensity and duration of drug action. The discovery of genetic polymorphisms of drug metabolizing enzymes (e.g., N-acetyltransferase 2 (NAT 2) and cytochrome P450 enzymes CYP2D6 and CYP2C19) has provided an explanation as to why some patients do not obtain the expected drug effects or show exaggerated drug response and serious toxicity after taking the standard and safe dose of a drug. These polymorphisms are expressed in two phenotypes in the population, the extensive metabolizer (EM) and poor metabolizer (PM). The prevalence of PM is different among different populations. For example, the gene coding for CYP2D6 is highly polymorphic and several mutations have been identified in PM, which all lead to the absence of functional CYP2D6. Poor metabolizers of CYP2D6 and CYP2C19 quite frequently experience exaggerated drug response and side effects when they receive standard doses. If a metabolite is the active therapeutic moiety, a PM will show no therapeutic response, as demonstrated for the analgesic effect of codeine mediated by its CYP2D6-formed metabolite morphine. The other extreme are the so called ultra-rapid metabolizers who do not respond to standard doses. Recently, the molecular basis of ultra-rapid metabolism has been identified to be due to CYP2D6 gene amplification.

[0310] Thus, the level of expression of a marker of the invention in an individual can be determined to thereby select appropriate agent(s) for therapeutic or prophylactic treatment of the individual. In addition, pharmacogenetic studies can be used to apply genotyping of polymorphic alleles encoding drug-metabolizing enzymes to the identification of an individual's drug responsiveness phenotype. This knowledge, when applied to dosing or drug selection, can avoid adverse reactions or therapeutic failure and thus enhance therapeutic or prophylactic efficiency when treating a subject with a modulator of expression of a marker of the invention.

[0311] C. Monitoring Clinical Trials

[0312] Monitoring the influence of agents (e.g., drug compounds) on the level of expression of a marker of the invention can be applied not only in basic drug screening, but also in clinical trials. For example, the effectiveness of an agent to affect marker expression can be monitored in clinical trials of subjects receiving treatment for colon cancer. In a preferred embodiment, the present invention provides a method for monitoring the effectiveness of treatment of a subject with an agent (e.g., an agonist, antagonist, peptidomimetic, protein, peptide, nucleic acid, small molecule, or other drug candidate) comprising the steps of (i) obtaining a pre-administration sample from a subject prior to administration of the agent; (ii) detecting the level of expression of one or more selected markers of the invention in the pre-administration sample; (iii) obtaining one or more post-administration samples from the subject; (iv) detecting the level of expression of the marker(s) in the post-administration samples; (v) comparing the level of expression of the marker(s) in the pre-administration sample with the level of expression of the marker(s) in the post-administration sample or samples; and (vi) altering the administration of the agent to the subject accordingly. For example, increased expression of the marker gene(s) during the course of treatment may indicate ineffective dosage and the desirability of increasing the dosage. Conversely, decreased expression of the marker gene(s) may indicate efficacious treatment and no need to change dosage.

[0313] D. Electronic Apparatus Readable Media and Arrays

[0314] Electronic apparatus readable media comprising a marker of the present invention is also provided. As used herein, “electronic apparatus readable media” refers to any suitable medium for storing, holding or containing data or information that can be read and accessed directly by an electronic apparatus. Such media can include, but are not limited to: magnetic storage media, such as floppy discs, hard disc storage medium, and magnetic tape; optical storage media such as compact disc; electronic storage media such as RAM, ROM, EPROM, EEPROM and the like; general hard disks and hybrids of these categories such as magnetic/optical storage media. The medium is adapted or configured for having recorded thereon a marker of the present invention.

[0315] As used herein, the term “electronic apparatus” is intended to include any suitable computing or processing apparatus or other device configured or adapted for storing data or information. Examples of electronic apparatus suitable for use with the present invention include stand-alone computing apparatus; networks, including a local area network (LAN), a wide area network (WAN) Internet, Intranet, and Extranet; electronic appliances such as a personal digital assistants (PDAs), cellular phone, pager and the like; and local and distributed processing systems.

[0316] As used herein, “recorded” refers to a process for storing or encoding information on the electronic apparatus readable medium. Those skilled in the art can readily adopt any of the presently known methods for recording information on known media to generate manufactures comprising the markers of the present invention.

[0317] A variety of software programs and formats can be used to store the marker information of the present invention on the electronic apparatus readable medium. For example, the marker nucleic acid sequence can be represented in a word processing text file, formatted in commercially-available software such as WordPerfect and MicroSoft Word, or represented in the form of an ASCII file, stored in a database application, such as DB2, Sybase, Oracle, or the like, as well as in other forms. Any number of data processor structuring formats (e.g., text file or database) may be employed in order to obtain or create a medium having recorded thereon the markers of the present invention.

[0318] By providing the markers of the invention in readable form, one can routinely access the marker sequence information for a variety of purposes. For example, one skilled in the art can use the nucleotide or amino acid sequences of the present invention in readable form to compare a target sequence or target structural motif with the sequence information stored within the data storage means. Search means are used to identify fragments or regions of the sequences of the invention which match a particular target sequence or target motif.

[0319] The present invention therefore provides a medium for holding instructions for performing a method for determining whether a subject has colon cancer or a pre-disposition to colon cancer, wherein the method comprises the steps of determining the presence or absence of a marker and based on the presence or absence of the marker, determining whether the subject has colon cancer or a pre-disposition to colon cancer and/or recommending a particular treatment for colon cancer or pre-colon cancer condition.

[0320] The present invention further provides in an electronic system and/or in a network, a method for determining whether a subject has colon cancer or a pre-disposition to colon cancer associated with a marker wherein the method comprises the steps of determining the presence or absence of the marker, and based on the presence or absence of the marker, determining whether the subject has colon cancer or a pre-disposition to colon cancer, and/or recommending a particular treatment for the colon cancer or pre-colon cancer condition. The method may further comprise the step of receiving phenotypic information associated with the subject and/or acquiring from a network phenotypic information associated with the subject.

[0321] The present invention also provides in a network, a method for determining whether a subject has colon cancer or a pre-disposition to colon cancer associated with a marker, said method comprising the steps of receiving information associated with the marker receiving phenotypic information associated with the subject, acquiring information from the network corresponding to the marker and/or colon cancer, and based on one or more of the phenotypic information, the marker, and the acquired information, determining whether the subject has a colon cancer or a pre-disposition to colon cancer. The method may further comprise the step of recommending a particular treatment for the colon cancer or pre-colon cancer condition.

[0322] The present invention also provides a business method for determining whether a subject has colon cancer or a pre-disposition to colon cancer, said method comprising the steps of receiving information associated with the marker, receiving phenotypic information associated with the subject, acquiring information from the network corresponding to the marker and/or colon cancer, and based on one or more of the phenotypic information, the marker, and the acquired information, determining whether the subject has colon cancer or a pre-disposition to colon cancer. The method may further comprise the step of recommending a particular treatment for the colon cancer or pre-colon cancer condition.

[0323] The invention also includes an array comprising a marker of the present invention. The array can be used to assay expression of one or more genes in the array. In one embodiment, the array can be used to assay gene expression in a tissue to ascertain tissue specificity of genes in the array. In this manner, up to about 7600 genes can be simultaneously assayed for expression. This allows a profile to be developed showing a battery of genes specifically expressed in one or more tissues.

[0324] In addition to such qualitative determination, the invention allows the quantitation of gene expression. Thus, not only tissue specificity, but also the level of expression of a battery of genes in the tissue is ascertainable. Thus, genes can be grouped on the basis of their tissue expression per se and level of expression in that tissue. This is useful, for example, in ascertaining the relationship of gene expression between or among tissues. Thus, one tissue can be perturbed and the effect on gene expression in a second tissue can be determined. In this context, the effect of one cell type on another cell type in response to a biological stimulus can be determined. Such a determination is useful, for example, to know the effect of cell-cell interaction at the level of gene expression. If an agent is administered therapeutically to treat one cell type but has an undesirable effect on another cell type, the invention provides an assay to determine the molecular basis of the undesirable effect and thus provides the opportunity to co-administer a counteracting agent or otherwise treat the undesired effect. Similarly, even within a single cell type, undesirable biological effects can be determined at the molecular level. Thus, the effects of an agent on expression of other than the target gene can be ascertained and counteracted.

[0325] In another embodiment, the array can be used to monitor the time course of expression of one or more genes in the array. This can occur in various biological contexts, as disclosed herein, for example development of colon cancer, progression of colon cancer, and processes, such a cellular transformation associated with colon cancer.

[0326] The array is also useful for ascertaining the effect of the expression of a gene on the expression of other genes in the same cell or in different cells. This provides, for example, for a selection of alternate molecular targets for therapeutic intervention if the ultimate or downstream target cannot be regulated.

[0327] The array is also useful for ascertaining differential expression patterns of one or more genes in normal and abnormal cells. This provides a battery of genes that could serve as a molecular target for diagnosis or therapeutic intervention.

[0328] E. Surrogate Markers

[0329] The markers of the invention may serve as surrogate markers for one or more disorders or disease states or for conditions leading up to disease states, and in particular, colon cancer. As used herein, a “surrogate marker” is an objective biochemical marker which correlates with the absence or presence of a disease or disorder, or with the progression of a disease or disorder (e.g., with the presence or absence of a tumor). The presence or quantity of such markers is independent of the disease. Therefore, these markers may serve to indicate whether a particular course of treatment is effective in lessening a disease state or disorder. Surrogate markers are of particular use when the presence or extent of a disease state or disorder is difficult to assess through standard methodologies (e.g., early stage tumors), or when an assessment of disease progression is desired before a potentially dangerous clinical endpoint is reached (e.g., an assessment of cardiovascular disease may be made using cholesterol levels as a surrogate marker, and an analysis of HIV infection may be made using HIV RNA levels as a surrogate marker, well in advance of the undesirable clinical outcomes of myocardial infarction or fully-developed AIDS). Examples of the use of surrogate markers in the art include: Koomen et al. (2000) J. Mass. Spectrom. 35: 258-264; and James (1994) AIDS Treatment News Archive 209.

[0330] The markers of the invention are also useful as pharmacodynamic markers. As used herein, a “pharmacodynamic marker” is an objective biochemical marker which correlates specifically with drug effects. The presence or quantity of a pharmacodynamic marker is not related to the disease state or disorder for which the drug is being administered; therefore, the presence or quantity of the marker is indicative of the presence or activity of the drug in a subject. For example, a pharmacodynamic marker may be indicative of the concentration of the drug in a biological tissue, in that the marker is either expressed or transcribed or not expressed or transcribed in that tissue in relationship to the level of the drug. In this fashion, the distribution or uptake of the drug may be monitored by the pharmacodynamic marker. Similarly, the presence or quantity of the pharmacodynamic marker may be related to the presence or quantity of the metabolic product of a drug, such that the presence or quantity of the marker is indicative of the relative breakdown rate of the drug in vivo. Pharmacodynamic markers are of particular use in increasing the sensitivity of detection of drug effects, particularly when the drug is administered in low doses. Since even a small amount of a drug may be sufficient to activate multiple rounds of marker transcription or expression, the amplified marker may be in a quantity which is more readily detectable than the drug itself. Also, the marker may be more easily detected due to the nature of the marker itself; for example, using the methods described herein, antibodies may be employed in an immune-based detection system for a protein marker, or marker-specific radiolabeled probes may be used to detect a mRNA marker. Furthermore, the use of a pharmacodynamic marker may offer mechanism-based prediction of risk due to drug treatment beyond the range of possible direct observations. Examples of the use of pharmacodynamic markers in the art include: Matsuda et al. U.S. Pat. No. 6,033,862; Hattis et al. (1991) Env. Health Perspect. 90: 229-238; Schentag (1999) Am. J. Health-Syst. Pharm. 56 Suppl. 3: S21-S24; and Nicolau (1999) Am. J. Health-Syst. Pharm. 56 Suppl. 3: S16-S20.

[0331] VI. Experimental Protocol

[0332] A. Identification of Markers

[0333] Colon cancer specific cDNA clones (i.e., those which are over-expressed in metastatic colon adenocarcinoma samples as compared to expression in normal colon and normal liver samples) were identified by transcription profiling using mRNA from 5 metastatic colon adenocarcinoma samples from sites of liver metastases, 3 normal colon samples and 2 pools of normal liver samples.

[0334] PCR products of the inserts from several thousand IMAGE clones comprising human cDNA inserts were spotted onto nylon membranes using a robotic gridding system linked to a sample database. RNA from clinical samples (metastatic colon adenocarcinomas, normal colon and normal liver) were used for hybridization against the nylon membranes. The RNA was labeled using an in vitro reverse transcription reaction that contains a radiolabeled nucleotide that is incorporated during the reaction. Hybridization experiments were performed by combining the radioactive products of the reverse transcription reaction with the nylon membranes in a hybridization chamber.

[0335] The expression levels of the cloned inserts in the metastatic colon adenocarcinoma samples were compared to their expression levels in the normal tissue samples. Inserts that expressed at least three-fold higher in at least 2 of the 5 metastatic colon adenocarcinoma samples as compared to their expression in the normal colon and liver samples were selected. Inserts corresponding to 319 genes were selected. Sequences comprising the selected inserts were obtained from the UNIGENE database using the identifier numbers of IMAGE clones containing the selected inserts. The sequences were used in BLAST searches of NCBI databases to identify genes and/or mRNAs comprising such sequences. Table 1 provides, if applicable, information relating to the identifier numbers of IMAGE clones containing the selected inserts, and the sequence(s) of the selected inserts. Table 1 also provides, if applicable, information relating to and the gene, mRNA and/or cDNA comprising or corresponding to the selected inserts. In certain instances, the inserts were independently sequenced, those sequences included in the accompanying Sequence Listing and the sequence listing identifiers included in Table 1.

[0336] Using the above described protocol, fourteen inserts were selected. Their sequences are included in the accompanying Sequence Listing. Table 2 provides the identifier number of the sequence of each insert.

[0337] VII. Summary of the Data Provided in the Tables

[0338] Table 1 lists the markers obtained using the foregoing protocol (markers n1-n319) and provides where applicable, the name of the gene corresponding to the marker (“Gene Name”), the identifier number(s) of IMAGE clone(s) containing a cDNA copy of a RNA transcript of the marker gene (“IMAGE Clone Id”), and the NCBI Protein and Nucleotide Database accession numbers of entries pertaining to: the IMAGE clone cDNA insert (“NCBI Accession # IMAGE clone insert”); a sequence comprising the cDNA insert (“NCBI GI # of IMAGE clone insert”); a mRNA encoded by the marker gene (“NCBI nuc accession #”); the cDNA sequence of the mRNA (“NCBI nuc GI #”); a protein encoded by the marker gene (“NCBI protein accession #”); and the amino acid sequence of the protein (“NCBI protein GI #”). The Sequence Listing identifier number marker (“SEQ ID NO (nt)”) of cDNA sequence of a nucleotide transcript encoded by or corresponding to the marker is also set forth in Table 1 (SEQ ID NOs:1-15).

[0339] Table 2 lists the markers obtained using the foregoing protocol (markers n320-n333) and provides the Sequence Listing identifier number (“SEQ ID NO (nts)”) of the cDNA sequence of a nucleotide transcript encoded by or corresponding to the marker (SEQ ID NOs:16-29).

[0340] The markers obtained using the foregoing protocol should not be construed as limiting. All database sequences referenced by the listed accession numbers numbers are expressly incorporated herein by reference. The contents of all references, patents and published patent applications cited throughout this application are also expressly incorporated herein by reference.

[0341] Other Embodiments

[0342] Those skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, many equivalents to the specific embodiments of the invention described herein. Such equivalents are intended to be encompassed by the following claims:

Claims

1. An isolated nucleic acid molecule comprising a nucleotide sequence selected from the group consisting of SEQ ID NOs: 1-29.

2. A vector which contains the nucleic acid molecule of claim 1.

3. A host cell which contains the nucleic acid molecule of claim 1.

4. An isolated polypeptide which is encoded by a nucleic acid molecule comprising a nucleotide sequence selected from the group consisting of SEQ ID NOs: 1-29.

5. An antibody which selectively binds to the polypeptide of claim 4.

6. A method of assessing whether a patient is afflicted with colon cancer, the method comprising comparing: a) the level of expression of a marker in a patient sample, wherein the marker is selected from the group consisting of n1-n333; and b) the normal level of expression of the marker in a control non-colon cancer sample, wherein a significant increase in the level of expression of the marker in the patient sample and the normal level is an indication that the patient is afflicted with colon cancer.