Patent Application
20170198019
The present invention relates to providing improved cell-permeable (iCP)-SOCS3 recombinant protein and uses thereof. Preferably, the iCP-SOCS3 recombinant protein may be used as protein-based anti-lung cancer agent by utilizing the platform technology for macromolecule intracellular transduction.
Worldwide, lung cancer is the most common cause of cancer-related death in men and women, and was responsible for 1.56 million deaths annually. There are two main types of primary lung cancer: non-small cell lung cancer (NSCLC), small cell lung cancer (SCLC). About 85% of lung cancers are NSCLCs which is the most common type of lung cancer. Squamous cell carcinoma, adenocarcinoma, and large cell carcinoma are all subtypes of non-small cell lung cancer. Cytokines including IL-6 and interferon-gamma (IFN-γ) activate the Janus kinase (JAK)/signal transducers and activators of transcription (STAT) signaling pathway, a vital role promoting the inflammation, carcinogenesis and metastasis in the lung. STAT3, which functions as an oncogene downstream of IL-6/gp130, is hyper-activated in lung cancer cells contributes to increase cell proliferation and inhibits apoptosis.
Cytokine signaling is strictly regulated by the SOCS family proteins induced by different classes of agonists, including cytokines, hormones and infectious agents. Among them, SOCS1 and SOCS3 are relatively specific to STAT1 and STAT3, respectively. SOCS1 inhibits JAK activation through its N-terminal kinase inhibitory region (KIR) by the direct binding to the activation loop of JAKs, while SOCS3 binds to janus kinases (JAKs)-proximal sites on the receptor through its SH2 domain and inhibits JAK activity that blocks recruitment of STAT3. Both promote anti-inflammatory effects due to the suppression of inflammation-inducing cytokine signaling. Furthermore, the SOCS box, another domain in SOCS proteins, interacts with E3 ubiquitin ligases and/or couples the SH2 domain-binding proteins to the ubiquitin-proteasome pathway. Therefore, SOCSs inhibit cytokine signaling by suppressing JAK kinase activity and degrading the activated cytokine receptor complex.
A previous study has confirmed that SOCS3 may significantly inhibit the proliferation of lung cancer cells in vitro and indicated that SOCS3 may act as an anti-oncogene involved in the development of tumors. Furthermore, SOCS3 may regulate the movement and migration of tumor cells. Methylation-mediated silencing of SOCS3 has been reported in non-small cell lung cancer (NSCLC) and other human cancers. In addition to the effect of SOCS3 in inflammation, abnormalities of the JAK/STAT pathway are also associated with cancer. It has been reported that methylationin of CpG islands in the functional SOCS3 promoter is correlated with its transcription silencing in the lung cancer cell lines. Restoration of SOCS3 in lung cancer cells where SOCS3 was methylation-silenced resulted in the down-regulation of active STAT3, induction of apoptosis, and growth suppression of cancer cells. It means that SOCS3 silencing is one of the important mechanisms of constitutive activation of the JAK/STAT pathway in cancer pathogenesis. Therefore, it can be suggested that intracellular SOCS3 protein replacement therapy may be useful in the treatment of lung cancer.
In the previous study, recombinant SOCS3 proteins that contain a cell-penetrating peptide (CPP)—membrane-translocating motif (MTM) from fibroblast growth factor (FGF)-4 has been reported to negatively control JAK/STAT signaling. These recombinant SOCS3 proteins inhibited STAT phosphorylation, inflammatory cytokines production and MHC-II expression in cultured and primary macrophages. In addition, SOCS3 fused to MTM protected mice challenged with a lethal dose of the SEB super-antigen, by suppressing apoptosis and hemorrhagic necrosis in multiple organs. However, the SOCS3 proteins fused to FGF4-derived MTM displayed extremely low solubility, poor yields and relatively low cell- and tissue-permeability. Therefore, the MTM-fused SOCS3 proteins were not suitable for further clinical development as therapeutic agents.
For MITT, six critical factors (length, bending potential, instability index, aliphatic index, GRAVY, amino acid composition) have been determined through analysis of baseline hydrophobic CPPs. Advanced macromolecule transduction domain (aMTD), newly designed based on these six critical factors, could optimize cell-/tissue-permeability of SOCS3 proteins that have a therapeutic effects and develop them as protein-based drugs. Further, in order to increase solubility and yield of recombinant protein, solubilization domains (SDs) additionally fused to the aMTD-SOCS3 recombinant protein, thereby notably increased the solubility and manufacturing yield of the recombinant protein.
In this application, aMTD/SD-fused iCP-SOCS3 recombinant proteins (iCP-SOCS3), much improved physicochemical characteristics (solubility and yield) and functional activity (cell-/tissue-permeability) compared with the protein fused only to FGF-4-derived MTM. In addition, the newly developed iCP-SOCS3 proteins have now been demonstrated to have therapeutic application in treating lung cancer cells, exploiting the ability of SOCS3 to suppress JAK/STAT signaling. The present application represents that macromolecule intracellular transduction technology (MITT) enabled by the new hydrophobic CPPs that are aMTD may provide novel protein therapy through SOCS3-intracellular protein replacement against the lung cancer cells. These findings suggest that restoration of SOCS3 by replenishing the intracellular SOCS3 with iCP-SOCS3 protein creates a new paradigm for anti-cancer therapy, and the intracellular protein replacement therapy with the SOCS3 recombinant protein fused to the combination of aMTD and SD pair may be useful to treat the lung cancer.
One aspect disclosed in the present application provides an improved Cell-Permeable (iCP)-SOCS3 recombinant protein, which comprises a SOCS3 protein; and at least one advanced macromolecule transduction domain (aMTD)(s) being composed of 9-13 amino acid sequences and having improved cell and/or tissue permeability, wherein the aMTD(s) is fused to one end or both ends of the SOCS3 protein and has the following features of:
(a) being composed of 3 or more amino acid sequences selected from the group consisting of Ala, Val, Ile, Leu, and Pro;
(b) having proline as amino acid sequences corresponding to any one or more of positions 5 to 8, and 12 of its amino acid sequence; and
(c) having an instability index of 40-60; an aliphatic index of 180-220; and a grand average of hydropathy (GRAVY) of 2.1-2.6, as measured by Protparam.
According to one embodiment, the iCP-SOCS3 recombinant protein further comprises one or more solubilization domain (SD)(s), and the aMTD(s), SOCS3 protein and SD(s) may be randomly fused to one another.
According to another embodiment, the aMTD may form α-Helix structure. According to still another embodiment, the aMTD may be composed of 12 amino acid sequences and represented by the following general formula:
wherein X(s) independently refer to Alanine (A), Valine (V), Leucine (L) or Isoleucine (I); and Proline (P) can be positioned in one of U(s) (either 5′, 6′, 7′ or 8′). The remaining U(s) are independently composed of A, V, L or I, P at the 12′ is Proline.
Another aspect disclosed in the present application provides an iCP-SOCS3 recombinant protein which is represented by any one of the following structural formulae:
A-B-C, A-C-B, B-A-C, B-C-A, C-A-B, C-B-A, A-C-B-C and other possible combinations,
wherein A is an advanced macromolecule transduction domain (aMTD) having improved cell and/or tissue permeability, B is a SOCS3 protein, and C is a solubilization domain (SD); and
the aMTD is composed of 9˜13 amino acid sequences and has the following features of:
(a) being composed of 3 or more amino acids selected from the group consisting of Ala, Val, Ile, Leu, and Pro;
(b) having proline as amino acid sequences corresponding to any one or more of positions 5 to 8, and 12 of its amino acid sequence;
(c) having an instability index of 40-60; an aliphatic index of 180-220; and a grand average of hydropathy (GRAVY) of 2.1-2.6, as measured by Protparam; and
(d) forming α-Helix structure.
According to one embodiment disclosed in the present application, the SOCS3 protein may have an amino acid sequence of SEQ ID NO: 814.
According to another embodiment disclosed in the present application, the SOCS3 protein may be encoded by a polynucleotide sequence of SEQ ID NO: 815.
According to still another embodiment disclosed in the present application, the SOCS3 protein may further include a ligand selectively binding to a receptor of a cell, a tissue, or an organ.
According to still another embodiment disclosed in the present application, the at least one aMTD(s) may have an amino acid sequence independently selected from the group consisting of SEQ ID NOs: 1˜240 and 822.
According to still another embodiment disclosed in the present application, the at least one aMTD(s) may be encoded by a polynucleotide sequence independently selected from the group consisting of SEQ ID NOs: 241˜480 and 823.
According to still another embodiment disclosed in the present application, the one or more SD(s) may have an amino acid sequence independently selected from the group consisting of SEQ ID NOs: 798, 799, 800, 801, 802, 803, and 804.
According to still another embodiment disclosed in the present application, the one or more SD(s) may be encoded by a polynucleotide sequence independently selected from the group consisting of SEQ ID NOs: 805, 806, 807, 808, 809, 810, and 811.
According to still another embodiment disclosed in the present application, the iCP-SOCS3 recombinant protein may have a histidine-tag affinity domain additionally fused to one end thereof.
According to still another embodiment disclosed in the present application, the histidine-tag affinity domain may have an amino acid sequence of SEQ ID NO: 812.
According to still another embodiment disclosed in the present application, the histidine-tag affinity domain may be encoded by a polynucleotide sequence of SEQ ID NO: 813.
According to still another embodiment disclosed in the present application, the fusion may be formed via a peptide bond or a chemical bond.
According to still another embodiment disclosed in the present application, the iCP-SOCS3 recombinant protein may be used for the treating, preventing, or delaying the onset of, lung cancer.
Still another aspect disclosed in the present application provides a polynucleotide sequence encoding the iCP-SOCS3 recombinant protein.
Still another aspect disclosed in the present application provides a recombinant expression vector including the polynucleotide sequence.
Still another aspect disclosed in the present application provides a transformant transformed with the recombinant expression vector.
Still another aspect disclosed in the present application provides a preparing method of the iCP-SOCS3 recombinant protein including preparing the recombinant expression vector; preparing the transformant using the recombinant expression vector; culturing the transformant; and recovering the recombinant protein expressed by the culturing.
Still another aspect disclosed in the present application provides a composition including the iCP-SOCS3 recombinant protein as an active ingredient.
Still another aspect disclosed in the present application provides a pharmaceutical composition for the treating, preventing, or delaying the onset of, lung cancer including the iCP-SOCS3 recombinant protein as an active ingredient; and a pharmaceutically acceptable carrier.
Still another aspect disclosed in the present application provides use of the iCP-SOCS3 recombinant protein as a medicament for the treating, preventing, or delaying the onset of, lung cancer.
Still another aspect disclosed in the present application provides a medicament including the iCP-SOCS3 recombinant protein.
Still another aspect disclosed in the present application provides use of the iCP-SOCS3 recombinant protein in the preparation of a medicament for the treating, preventing, or delaying the onset of, lung cancer.
Still another aspect disclosed in the present application provides a method of treating, preventing, or delaying the onset of, lung cancer in a subject, the method including identifying a subject in need of the treating, preventing, or delaying the onset of, lung cancer; and administering to the subject a therapeutically effective amount of the iCP-SOCS3 recombinant protein.
According to one embodiment disclosed in the present application, the subject may be a mammal.
Unless defined otherwise, all terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs. Although a certain method and a material is described herein, it should not be construed as being limited thereto, any similar or equivalent method and material to those may also be used in the practice or testing of the present invention. All publications mentioned herein are incorporated herein by reference in their entirety to disclose and describe the methods and/or materials in connection with which the publications are cited. It must be noted that as used herein and in the appended claims, the singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise.
A “peptide,” as used herein, refers to a chain-type polymer formed by amino acid residues which are linked to each other via peptide bonds, and used interchangeably with “polypeptide.” Further, a “polypeptide” includes a peptide and a protein.
Further, the term “peptide” includes amino acid sequences that are conservative variations of those peptides specifically exemplified herein. The term “conservative variation,” as used herein, denotes the replacement of an amino acid residue by another, biologically similar residue. Examples of conservative variations include substitution of one hydrophobic residue, such as isoleucine, valine, leucine, alanine, cysteine, glycine, phenylalanine, proline, tryptophan, tyrosine, norleucine, or methionine for another, or substitution of one polar residue for another, for example, substitution of arginine for lysine, glutamic acid for aspartic acid, or glutamine for asparagine, and the like. Neutral hydrophilic amino acids which may be substituted for one another include asparagine, glutamine, serine, and threonine.
The term “conservative variation” also includes use of a substituted amino acid in place of an unsubstituted parent amino acid, provided that antibodies raised to the substituted polypeptide also immunoreact with the unsubstituted polypeptide. Such conservative substitutions are within the definition of the classes of the peptides disclosed in the present application.
A person having ordinary skill in the art may make similar substitutions to obtain peptides having higher cell permeability and a broader host range. For example, one aspect disclosed in the present application provides peptides corresponding to amino acid sequences (e.g. SEQ ID NOs: 1 to 240 and 822) provided herein, as well as analogues, homologs, isomers, derivatives, amidated variations, and conservative variations thereof, as long as the cell permeability of the peptide remains.
Minor modifications to primary amino acid sequence disclosed in the present application may result in peptides which have substantially equivalent or enhanced cell permeability, as compared to the specific peptides described herein. Such modifications may be deliberate, as by site-directed mutagenesis, or may be spontaneous.
All peptides may be synthesized using L-amino acids, but D forms of all of the peptides may be synthetically produced. In addition, C-terminal derivatives, such as C-terminal methyl esters and C-terminal amidates, may be produced in order to increase the cell permeability of the peptide according to one embodiment disclosed in the present application.
All of the peptides produced by these modifications are included herein, as long as in the case of amidated versions of the peptide, the cell permeability of the original peptide is altered or enhanced such that the amidated peptide is therapeutically useful. It is envisioned that such modifications are useful for altering or enhancing cell permeability of a particular peptide.
Furthermore, deletion of one or more amino acids may also result in a modification to the structure of the resultant molecule without any significant change in its cell permeability. This may lead to the development of a smaller active molecule which may also have utility. For example, amino- or carboxyl-terminal amino acids which may not be required for the cell permeability of a particular peptide may be removed.
The term “gene” refers to an arbitrary nucleic acid sequence or a part thereof having a functional role in protein coding or transcription, or regulation of other gene expression. The gene may be composed of all nucleic acids encoding a functional protein or a part of the nucleic acid encoding or expressing the protein. The nucleic acid sequence may include a gene mutation in exon, intron, initiation or termination region, promoter sequence, other regulatory sequence, or a unique sequence adjacent to the gene.
The term “primer” refers to an oligonucleotide sequence that hybridizes to a complementary RNA or DNA target polynucleotide and serves as the starting points for the stepwise synthesis of a polynucleotide from mononucleotides by the action of a nucleotidyltransferase as occurs, for example, in a polymerase chain reaction.
The term “coding region” or “coding sequence” refers to a nucleic acid sequence, a complement thereof, or a part thereof which encodes a particular gene product or a fragment thereof for which expression is desired, according to the normal base pairing and codon usage relationships. Coding sequences include exons in genomic DNA or immature primary RNA transcripts, which are joined together by the cellular biochemical machinery to provide a mature mRNA. The anti-sense strand is the complement of the nucleic acid, and the coding sequence may be deduced therefrom.
One aspect disclosed in the present application provides an iCP-SOCS3 recombinant protein, which comprises a SOCS3 protein and at least one advanced macromolecule transduction domain (aMTD)(s) being composed of 9-13 amino acid sequences, preferably 10-12 amino acid sequences, and having improved cell and/or tissue permeability, wherein the aMTD is fused to one end or both ends of the SOCS3 protein and has the following features of:
(a) being preferably composed of 3 or more amino acid sequences selected from the group consisting of Ala, Val, Ile, Leu, and Pro;
(b) having proline as amino acid sequences corresponding to any one or more of positions 5 to 8, and 12 of its amino acid sequence, and preferably one or more of positions 5 to 8 and position 12 of its amino acid sequence; and
(c) having an instability index of preferably 40-60 and more preferably 41-58; an aliphatic index of preferably 180-220 and more preferably 185-225; and a grand average of hydropathy (GRAVY) of preferably 2.1-2.6 and more preferably 2.2-2.6 as measured by Protparam (see http://web.expasy.org/protparam/).
These critical factors that facilitate the cell permeable ability of aMTD sequences were analyzed, identified, and determined according to one embodiment disclosed in the present application. These aMTD sequences are artificially assembled based on the critical factors (CFs) determined from in-depth analysis of previously published hydrophobic CPPs.
The aMTD sequences according to one aspect disclosed in the present application are the first artificially developed cell permeable polypeptides capable of mediating the transduction of biologically active macromolecules—including peptides, polypeptides, protein domains, or full-length proteins—through the plasma membrane of cells.
According to one embodiment, the iCP-SOCS3 recombinant protein further comprises one or more solubilization domain (SD)(s), and the aMTD(s), SOCS3 protein and SD(s) may be randomly fused to one another. For example, SD(s) may be further fused to one or more of the SOCS3 protein and the aMTD, preferably to one end or both ends of the SOCS3 protein, and more preferably to the C-terminus of the SOCS3 protein.
According to another embodiment, the aMTD may form α-Helix structure.
According to still another embodiment, the aMTD may be preferably composed of 12 amino acid sequences and represented by the following general formula:
Here, X(s) independently refer to Alanine (A), Valine (V), Leucine (L) or Isoleucine (I); and Proline (P) can be positioned in one of U(s) (either 5′, 6′, 7′ or 8′). The remaining U(s) are independently composed of A, V, L or I, P at the 12′ is Proline.
Still another aspect disclosed in the present application provides an iCP-SOCS3 recombinant protein which is represented by any one of structural formulae A-B-C, A-C-B, B-A-C, B-C-A, C-A-B, C-B-A, A-C-B-C and other possible combinations, preferably by A-B-C or C-B-A:
wherein A is an advanced macromolecule transduction domain (aMTD) having improved cell and/or tissue permeability, and if the iCP-SOCS3 recombinant protein comprises two or more aMTDs, they can be same or different; B is a SOCS3 protein, and C is a solubilization domain (SD), and if the iCP-SOCS3 recombinant protein comprises two or more SDs, they can be same or different; and
the aMTD is composed of 9-13, preferably 10-12 amino acid sequences and has the following features of:
(a) being composed of 3 or more amino acid sequences selected from the group consisting of Ala, Val, Ile, Leu, and Pro;
(b) having proline as amino acid sequences corresponding to any one or more of positions 5 to 8, and 12 of its amino acid sequence, and preferably, one or more of positions 5 to 8 and position 12 of its amino acid sequence;
(c) having an instability index of 40-60, preferably 41-58 and more preferably 50-58; an aliphatic index of 180-220. preferably 185-225 and more preferably 195-205; and a grand average of hydropathy (GRAVY) of 2.1-2.6 and preferably 2.2-2.6, as measured by Protparam (see http://web.expasy.org/protparam/); and
(d) preferably forming t-Helix structure.
In one embodiment disclosed in the present application, the SOCS3 protein may have an amino acid sequence of SEQ ID NO: 814.
In another embodiment disclosed in the present application, the SOCS3 protein may be encoded by a polynucleotide sequence of SEQ ID NO: 815.
When the iCP-SOCS3 recombinant protein is intended to be delivered to a particular cell, tissue, or organ, the SOCS3 protein may form a fusion product, together with an extracellular domain of a ligand capable of selectively binding to a receptor which is specifically expressed on the particular cell, tissue, or organ, or monoclonal antibody (mAb) capable of specifically binding to the receptor or the ligand and a modified form thereof.
The binding of the peptide and a biologically active substance may be formed either by indirect linkage by a cloning technique using an expression vector at a nucleotide level or by direct linkage via chemical or physical covalent or non-covalent bond of the peptide and the biologically active substance.
In still another embodiment disclosed in the present application, the SOCS3 protein may preferably further include a ligand selectively binding to a receptor of a cell, a tissue, or an organ.
In one embodiment disclosed in the present application, the at least one aMTD(s) may have an amino acid sequence independently selected from the group consisting of SEQ ID NOs: 1˜240 and 822, preferably SEQ ID NOs: 2, 16, 22, 32, 40, 43, 63, 65, 77, 84, 85, 86, 110, 131, 142, 143, 177, 228, 229, 233, 237, 239 and 822, more preferably SEQ ID NO: 43.
In still another embodiment disclosed in the present application, the at least one aMTD may be encoded by a polynucleotide sequence independently selected from the group consisting of SEQ ID NOs: 241˜480 and 823, preferably SEQ ID NOs: 242, 256, 262, 272, 280, 283, 303, 305, 317, 324, 325, 326, 350, 371, 382, 383, 417, 468, 469 473, 477, 479 and 823, more preferably SEQ ID NO: 283.
In still another embodiment disclosed in the present application, the one or more SD(s) may have an amino acid sequence independently selected from the group consisting of SEQ ID NOs: 798, 799, 800, 801, 802, 803, and 804. The SD may be preferably SDA of SEQ ID NO: 798, SDB of SEQ ID NO: 799, or SDB′ of SEQ ID NO: 804, and more preferably, SDB of SEQ ID NO: 799 which has superior structural stability, or SDB′ of SEQ ID NO: 804 which has a modified amino acid sequence of SDB to avoid immune responses upon in vivo application. The modification of the amino acid sequence in SDB may be replacement of an amino acid residue, Valine, corresponding to position 28 of the amino acid sequence of SDB (SEQ ID NO: 799) by Leucine.
In still another embodiment disclosed in the present application, the one or more SDs may be encoded by a polynucleotide sequence independently selected from the group consisting of SEQ ID NOs: 805, 806, 807, 808, 809, 810, and 811. The SD may be preferably SDA encoded by a polynucleotide sequence of SEQ ID NO: 805, SDB encoded by a polynucleotide sequence of SEQ ID NO: 806, or SDB′ for deimmunization (or humanization) encoded by a polynucleotide sequence of SEQ ID NO: 811, and more preferably, SDB having superior structural stability, which is encoded by a polynucleotide sequence of SEQ ID NO: 806, or SDB′ having a modified polynucleotide sequence of SDB to avoid immune responses upon in vivo application, which is encoded by a polynucleotide sequence of SEQ ID NO: 811.
In still another embodiment disclosed in the present application, the iCP-SOCS3 recombinant protein may be preferably selected from the group consisting of:
1) a recombinant protein, in which SOCS3 having an amino acid sequence of SEQ ID NO: 814 is fused to the N-terminus or the C-terminus of aMTD having any one amino acid sequence selected from the group consisting of SEQ ID NOs: 1 to 240 and 822, 2, 16, 22, 32, 40, 43, 63, 65, 77, 84, 85, 86, 110, 131, 142, 143, 177, 228, 229, 233, 237, 239 and 822, more preferably SEQ ID NO: 43;
2) a recombinant protein, in which SD having any one amino acid sequence selected from the group consisting of SEQ ID NOs: 798 to 804 is further fused to one or more of the N-terminus or the C-terminus of the SOCS3 and aMTD in the recombinant protein of 1); and
3) a recombinant protein, in which a Histidine tag having an amino acid sequence of 812 is further fused to the N-terminus of the recombinant protein of 1) or 2).
The SOCS3 protein may exhibit a physiological phenomenon-related activity or a therapeutic purpose-related activity by intracellular or in-vivo delivery. The recombinant expression vector may include a tag sequence which makes it easy to purify the recombinant protein, for example, consecutive histidine codon, maltose binding protein codon, Myc codon, etc., and further include a fusion partner to enhance solubility of the recombinant protein, etc. Further, for the overall structural and functional stability of the recombinant protein or flexibility of the proteins encoded by respective genes, the recombinant expression vector may further include one or more glycine, proline, and spacer amino acid or polynucleotide sequences including AAY amino acids. Furthermore, the recombinant expression vector may include a sequence specifically digested by an enzyme in order to remove an unnecessary region of the recombinant protein, an expression regulatory sequence, and a marker or reporter gene sequence to verify intracellular delivery, but is not limited thereto.
In still another embodiment disclosed in the present application, the iCP-SOCS3 recombinant protein may preferably have a histidine-tag affinity domain additionally fused to one end thereof.
In still another embodiment disclosed in the present application, the histidine-tag affinity domain may have an amino acid sequence of SEQ ID NO: 812.
In still another embodiment disclosed in the present application, the histidine-tag affinity domain may be encoded by a polynucleotide sequence of SEQ ID NO: 813.
In still another embodiment disclosed in the present application, the fusion may be formed via a peptide bond or a chemical bond.
The chemical bond may be preferably selected from the group consisting of disulfide bonds, diamine bonds, sulfide-amine bonds, carboxyl-amine bonds, ester bonds, and covalent bonds.
In still another embodiment disclosed in the present application, the iCP-SOCS3 recombinant protein may be used for the treating, preventing, or delaying the onset of, lung cancer.
Still another aspect disclosed in the present application provides a polynucleotide sequence encoding the iCP-SOCS3.
According to still another embodiment disclosed in the present application, the polynucleotide sequence may be fused with a histidine-tag affinity domain.
Still another aspect disclosed in the present application provides a recombinant expression vector including the polynucleotide sequence.
Preferably, the vector may be inserted in a host cell and recombined with the host cell genome, or refers to any nucleic acid including a nucleotide sequence competent to replicate spontaneously as an episome. Such a vector may include a linear nucleic acid, a plasmid, a phagemid, a cosmid, an RNA vector, a viral vector, etc.
Preferably, the vector may be genetically engineered to incorporate the nucleic acid sequence encoding the recombinant protein in an orientation either N-terminal and/or C-terminal to a nucleic acid sequence encoding a peptide, a polypeptide, a protein domain, or a full-length protein of interest, and in the correct reading frame so that the recombinant protein consisting of aMTD, SOCS3 protein, and preferably SD may be expressed. Expression vectors may be selected from those readily available for use in prokaryotic or eukaryotic expression systems.
Standard recombinant nucleic acid methods may be used to express a genetically engineered recombinant protein. The nucleic acid sequence encoding the recombinant protein according to one embodiment disclosed in the present application may be cloned into a nucleic acid expression vector, e.g., with appropriate signal and processing sequences and regulatory sequences for transcription and translation, and the protein may be synthesized using automated organic synthetic methods. Synthetic methods of producing proteins are described in, for example, the literature [Methods in Enzymology, Volume 289: Solid-Phase Peptide Synthesis by Gregg B. Fields (Editor), Sidney P. Colowick, Melvin I. Simon (Editor), Academic Press (1997)].
In order to obtain high level expression of a cloned gene or nucleic acid, for example, a cDNA encoding the recombinant protein according to one embodiment disclosed in the present application, the recombinant protein sequence may be typically subcloned into an expression vector that includes a strong promoter for directing transcription, a transcription/translation terminator, and in the case of a nucleic acid encoding a protein, a ribosome binding site for translational initiation. Suitable bacterial promoters are well known in the art and are described, e.g., in the literatures [Sambrook & Russell, Molecular Cloning: A Laboratory Manual, 3d Edition, Cold Spring Harbor Laboratory, N.Y. (2001); and Ausubel, et al., Current Protocols in Molecular Biology, Greene Publishing Associates and Wiley Interscience, N. Y. (1989)]. Bacterial expression systems for expression of the recombinant protein are available in, e.g., E. coli, Bacillus sp., and Salmonella (Palva et al., Gene 22: 229-235 (1983); Mosbach et al., Nature 302: 543-545 (1983)). Kits for such expression systems are commercially available. Eukaryotic expression systems for mammalian cells, yeast, and insect cells are well known in the art and are also commercially available. The eukaryotic expression vector may be preferably an adenoviral vector, an adeno-associated vector, or a retroviral vector.
Generally, the expression vector for expressing the cell permeable recombinant protein according to one embodiment disclosed in the present application in which the cargo protein, i.e. ΔSOCS3 protein, is attached to the N-terminus, C-terminus, or both termini of aMTD may include regulatory sequences including, for example, a promoter, operably attached to a sequence encoding the advanced macromolecule transduction domain. Non-limiting examples of inducible promoters that may be used include steroid-hormone responsive promoters (e.g., ecdysone-responsive, estrogen-responsive, and glutacorticoid-responsive promoters), tetracycline “Tet-On” and “Tet-Off” systems, and metal-responsive promoters.
The polynucleotide sequence according to one embodiment disclosed in the present application may be present in a vector in which the polynucleotide sequence is operably linked to regulatory sequences capable of providing for the expression of the polynucleotide sequence by a suitable host cell.
According to one embodiment disclosed in the present application, the polynucleotide sequence may be selected from the following groups:
1) a polynucleotide sequence, in which any one polynucleotide sequence selected from the group consisting of SEQ ID NOs: 241˜480 and 823, preferably SEQ ID NOs: 242, 252, 274, 279, 322, 331, 338, 345, 347, 361, 365, 370, 371, 383, 387, 417, 462, 468, 469, 473, 477, 479 and 823, more preferably SEQ ID NO: 283, is operably linked with a polynucleotide sequence of SEQ ID NO: 815; and
2) a polynucleotide sequence, in which any one polynucleotide sequence selected from the group consisting of SEQ ID NOs: 805 to 811 is further operably linked to the polynucleotide sequence of 1), or further operably linked to between: any one polynucleotide sequence selected from the group consisting of SEQ ID NOs: 241˜480 and 823, preferably SEQ ID NOs: 242, 256, 262, 272, 280, 283, 303, 305, 317, 324, 325, 326, 350, 371, 382, 383, 417, 468, 469, 473, 477, 479 and 823, more preferably SEQ ID NO: 283; and a polynucleotide sequence of SEQ ID NO: 815.
Within an expression vector, the term “operably linked” is intended to mean that the polynucleotide sequence of interest is linked to the regulatory sequence(s) in a manner which allows for expression of the polynucleotide sequence. The term “regulatory sequence” is intended to include promoters, enhancers, and other expression control elements. Such operable linkage with the expression vector can be achieved by conventional gene recombination techniques known in the art, while site-directed DNA cleavage and linkage are carried out by using conventional enzymes known in the art.
The expression vectors may contain a signal sequence or a leader sequence for membrane targeting or secretion, as well as regulatory sequences such as a promoter, an operator, an initiation codon, a termination codon, a polyadenylation signal, an enhancer and the like. The promoter may be a constitutive or an inducible promoter. Further, the expression vector may include one or more selectable marker genes for selecting the host cell containing the expression vector, and may further include a polynucleotide sequence that enables the vector to replicate in the host cell in question.
The expression vector constructed according to one embodiment disclosed in the present application may be the vector where the polynucleotide encoding the iCP-SOCS3 recombinant protein (where an aMTD is fused to the N-terminus or C-terminus of a SOCS3 protein) is inserted within the multiple cloning sites (MCS), preferably within the Nde1/Sal1 site or BamH1/Sal1 site of a pET-28a(+)(Novagen, Darmstadt, Germany) or pET-26b(+) vector(Novagen, Darmstadt, Germany).
In still another embodiment disclosed in the present application, the polynucleotide encoding the SD being additionally fused to the N-terminus or C-terminus of a SOCS3 protein or an aMTD may be inserted into a cleavage site of restriction enzyme (Nde1, BamH1 and Sal1, etc.) within the multiple cloning sites (MCS) of a pET-28a(+)(Novagen, Darmstadt, Germany) or pET-26b(+) vector(Novagen, Darmstadt, Germany).
In still another embodiment disclosed in the present application, the polynucleotide encoding the iCP-SOCS3 recombinant protein may be cloned into a pET-28a(+) vector bearing a His-tag sequence so as to fuse six histidine residues to the N-terminus of the iCP-SOCS3 recombinant protein to allow easy purification.
According to one embodiment disclosed in the present application, the polynucleotide sequence may be a polynucleotide sequence selected from the group consisting of SEQ ID NOS: 824, 826, 828 and 830.
The recombinant protein may be introduced into an appropriate host cell, e.g., a bacterial cell, a yeast cell, an insect cell, or a tissue culture cell. The recombinant protein may also be introduced into embryonic stem cells in order to generate a transgenic organism. Large numbers of suitable vectors and promoters are known to those skilled in the art and are commercially available for generating the recombinant protein.
Known methods may be used to construct vectors including the polynucleotide sequence according to one embodiment disclosed in the present application and appropriate transcriptional/translational control signals. These methods include in vitro recombinant DNA techniques, synthetic techniques, and in vivo recombination/genetic recombination. For example, these techniques are described in the literatures [Sambrook & Russell, Molecular Cloning: A Laboratory Manual, 3d Edition, Cold Spring Harbor Laboratory, N. Y. (2001); and Ausubel et al., Current Protocols in Molecular Biology Greene Publishing Associates and Wiley Interscience, N.Y. (1989)].
Still another aspect disclosed in the present application provides a transformant transformed with the recombinant expression vector.
The transformation includes transfection, and refers to a process whereby a foreign (extracellular) DNA, with or without an accompanying material, enters into a host cell. The “transfected cell” refers to a cell into which the foreign DNA is introduced into the cell, and thus the cell harbors the foreign DNA. The DNA may be introduced into the cell so that a nucleic acid thereof may be integrated into the chromosome or replicable as an extrachromosomal element. The cell introduced with the foreign DNA, etc. is called a transformant.
As used herein, ‘introducing’ of a protein, a peptide, an organic compound into a cell may be used interchangeably with the expression of ‘carrying,’ ‘penetrating,’ ‘transporting,’ ‘delivering,’ ‘permeating’ or ‘passing.’
It is understood that the host cell refers to a eukaryotic or prokaryotic cell into which one or more DNAs or vectors are introduced, and refers not only to the particular subject cell but also to the progeny or potential progeny thereof. 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.
The host cells may be preferably bacterial cells, and as the bacterial cells, there are, in principle, no limitations. They may be eubacteria (gram-positive or gram-negative) or archaebacteria, as long as they allow genetic manipulation for insertion of a gene of interest, preferably for site-specific integration, and they may be cultured on a manufacturing scale. Preferably, the host cells may have the property to allow cultivation to high cell densities.
Examples of bacterial host cells that may be used in the preparation of the recombinant protein are E. coli (Lee, 1996; Hannig and Makrides, 1998), Bacillus subtilis, Pseudomonas fluorescens (Squires et al., 2004; Retallack et al., 2006) as well as various Corynebacterium (US 2006/0003404 A1) and Lactococcus lactis (Mierau et al., 2005) strains. Preferably, the host cells are Escherichia coli cells.
More preferably, the host cell may include an RNA polymerase capable of binding to a promoter regulating the gene of interest. The RNA polymerase may be endogenous or exogenous to the host cell.
Preferably, host cells with a foreign strong RNA polymerase may be used. For example, Escherichia coli strains engineered to carry a foreign RNA polymerase (e.g. like in the case of using a T7 promoter a T7-like RNA polymerase in the so-called “T7 strains”) integrated in their genome may be used. Examples of T7 strains, e.g. BL21(DE3), HMS174(DE3), and their derivatives or relatives (see Novagen, pET System manual, 11th edition), may be widely used and commercially available. Preferably, BL21-CodonPlus (DE3)-RIL or BL21-CodonPlus (DE3)-RIPL (Agilent Technologies) may be used. These strains are DE3 lysogens containing the T7 RNA polymerase gene under control of the lacUV5 promoter. Induction with IPTG allows production of T7 RNA polymerase which then directs the expression of the gene of interest under the control of the T7 promoter.
The host cell strains, E. coli BL21(DE3) or HMS174(DE3), which have received their genome-based T7 RNA polymerase via the phage DE3, are lysogenic. It is preferred that the T7 RNA polymerase contained in the host cell has been integrated by a method which avoids, or preferably excludes, the insertion of residual phage sequences in the host cell genome since lysogenic strains have the disadvantage to potentially exhibit lytic properties, leading to undesirable phage release and cell lysis.
Still another aspect disclosed in the present application provides a preparing method of the iCP-SOCS3 recombinant protein including preparing the recombinant expression vector; preparing the transformant using the recombinant expression vector; culturing the transformant; and recovering the recombinant protein expressed by culturing.
Culturing may be preferably in a mode that employs the addition of a feed medium, this mode being selected from the fed-batch mode, semi-continuous mode, or continuous mode, and the bacterial expression host cells may include a DNA construct, integrated in their genome, carrying the DNA sequence encoding the protein of interest under the control of a promoter that enables expression of said protein.
There are no limitations in the type of the culture medium. The culture medium may be semi-defined, i.e. containing complex media compounds (e.g. yeast extract, soy peptone, casamino acids), or it may be chemically defined, without any complex compounds. Preferably, a defined medium may be used. The defined media (also called minimal or synthetic media) are exclusively composed of chemically defined substances, i.e. carbon sources such as glucose or glycerol, salts, vitamins, and, in view of a possible strain auxotrophy, specific amino acids or other substances such as thiamine. Most preferably, glucose may be used as a carbon source. Usually, the carbon source of the feed medium serves as the growth-limiting component which controls the specific growth rate.
Host cells may be disrupted by any convenient method, including freeze-thaw cycling, sonication, mechanical disruption, or the use of cell lysing agents. The literature [Scopes, Protein Purification: Principles and Practice, New York: Springer-Verlag (1994)] describes a number of general methods for purifying recombinant (and non-recombinant) proteins. The methods may include, e.g., ion-exchange chromatography, size-exclusion chromatography, affinity chromatography, selective precipitation, dialysis, and hydrophobic interaction chromatography. These methods may be adapted to devise a purification strategy for the cell permeable recombinant protein. If the cell permeable recombinant protein includes a purification handle, such as an epitope tag or a metal chelating sequence, affinity chromatography may be used to easily purify the protein.
The amount of the protein produced may be evaluated by detecting the advanced macromolecule transduction domain directly (e.g., using Western analysis) or indirectly (e.g., by assaying materials derived from the cells for specific DNA binding activity, such as by electrophoretic mobility shift assay). Proteins may be detected prior to purification, during any stage of purification, or after purification. In some implementations, purification or complete purification may not be necessary.
The iCP-SOCS3 recombinant proteins according to one embodiment disclosed in the present application are cell permeable proteins, and may be used as protein-based vaccines, particularly in the case where killed or attenuated whole organism vaccines are impractical.
The iCP-SOCS3 recombinant proteins according to one embodiment disclosed in the present application may be preferably used for the treating, preventing, or delaying the onset of, lung cancer. The cell permeable recombinant proteins may be delivered to the interior of the cell, eliminating the need to transfect or transform the cell with a recombinant vector. The cell permeable recombinant proteins may be used in vitro to investigate protein function or may be used to maintain cells in a desired state.
Still another aspect disclosed in the present application provides a composition including the iCP-SOCS3 Recombinant Protein as an active ingredient.
Still another aspect disclosed in the present application provides a pharmaceutical composition for treating, preventing, or delaying the onset of, lung cancer including the iCP-SOCS3 Recombinant Protein as an active ingredient; and a pharmaceutically acceptable carrier.
According to one embodiment disclosed in the present application, the iCP-SOCS3 Recombinant Protein may be used in a single agent, or in combination with one or more other anti-cancer agents.
Lung cancers described herein include, but are not limited to, lung cell carcinomas, fibrolamellar variants of lung cancer cells, and mixed lung cancer cells cholangiocarcinomas. In addition, the lung cancer cells may be early stage lung cancer cells, non-metastatic lung cancer cells, primary lung cancer cells, advanced lung cancer cells, locally advanced lung cancer cells, metastatic lung cancer cells, lung cancer cells in remission, recurrent lung cancer cells, lung cancer cells in an adjuvant setting, or lung cancer cells in a neoadjuvant setting.
According to one embodiment disclosed in the present application, ling cancers may be small cell lung cancers or non-small cell lung cancers.
Preferably, the composition may be for injectable (e.g. intraperitoneal, intravenous, and intra-arterial, etc.) and may include the active ingredient in an amount of 0.001 mg/kg to 1000 mg/kg, preferably 0.01 mg/kg to 100 mg/kg, more preferably 0.1 mg/kg to 50 mg/kg for human.
For examples, dosages per day normally fall within the range of about 0.001 to about 1000 mg/kg of body weight. In the treatment of adult humans, the range of about 0.1 to about 50 mg/kg/day, in single or divided dose, is especially preferred. However, it will be understood that the concentration of the iCP-SOCS3 recombinant protein actually administered will be determined by a physician, in the light of the relevant circumstances, including the condition to be treated, the chosen route of administration, the age, weight, and response of the individual patient, and the severity of the patient's symptoms, and therefore the above dosage ranges are not intended to limit the scope of the invention in any way. In some instances dosage levels below the lower limit of the aforesaid range may be more than adequate, while in other cases still larger doses may be employed without causing any harmful side effect, provided that such larger doses are first divided into several smaller doses for administration throughout the day.
Still another aspect disclosed in the present application provides use of the iCP-SOCS3 recombinant protein as a medicament for treating, preventing, or delaying the onset of, lung cancer.
Still another aspect disclosed in the present application provides a medicament including the iCP-SOCS3 recombinant protein.
Still another aspect disclosed in the present application provides use of the iCP-SOCS3 recombinant protein for the preparation of a medicament for treating, preventing, or delaying the onset of, lung cancer.
Still another aspect disclosed in the present application provides a method of treating, preventing, or delaying the onset of, lung cancer in a subject including identifying a subject in need of treating, preventing, or delaying the onset of, lung cancer; and administering to the subject a therapeutically effective amount of the iCP-SOCS3 recombinant protein.
In one embodiment disclosed in the present application, the subject may be preferably a mammal.
Preferably, the subject in need of treating, preventing, or delaying the onset of, lung cancer may be identified by any conventional diagnostic methods known in the art including ultrasound, CT scan, MRI, alpha-fetoprotein testing, and biopsy, etc.
The pharmaceutical composition according to one embodiment disclosed in the present application may be prepared by using pharmaceutically suitable and physiologically acceptable additives, in addition to the active ingredient, and the additives may include excipients, disintegrants, sweeteners, binders, coating agents, blowing agents, lubricants, glidants, flavoring agents, etc.
For administration, the pharmaceutical composition may be preferably formulated by further including one or more pharmaceutically acceptable carriers in addition to the above-described active ingredient.
Dosage forms of the pharmaceutical composition may include granules, powders, tablets, coated tablets, capsules, suppositories, liquid formulations, syrups, juice, suspensions, emulsions, drops, injectable liquid formulations, etc. For formulation of the composition into a tablet or capsule, for example, the active ingredient may be combined with any oral, non-toxic pharmaceutically acceptable inert carrier, such as ethanol, glycerol, water, etc. If desired or necessary, suitable binders, lubricants, disintegrants, and colorants may be additionally included as a mixture.
Examples of the suitable binder may include, but are not limited to, starch, gelatin, natural sugars such as glucose or beta-lactose, corn sweeteners, natural and synthetic gums such as acacia, tragacanth, or sodium oleate, sodium stearate, magnesium stearate, sodium benzoate, sodium acetate, sodium chloride, etc. Examples of the disintegrant may include, but are not limited to, starch, methyl cellulose, agar, bentonite, xanthan gum, etc. For formulation of the composition into a liquid preparation, a pharmaceutically acceptable carrier which is sterile and biocompatible may be used, such as saline, sterile water, a Ringer's solution, buffered saline, an albumin infusion solution, a dextrose solution, a maltodextrin solution, glycerol, and ethanol, and these materials may be used alone or in any combination thereof. If necessary, other common additives, such as antioxidants, buffers, bacteriostatic agents, etc., may be added. Further, diluents, dispersants, surfactants, binders, and lubricants may be additionally added to prepare injectable formulations such as aqueous solutions, suspensions, and emulsions, or pills, capsules, granules, or tablets. Furthermore, the composition may be preferably formulated, depending upon diseases and ingredients, using any appropriate method known in the art, as disclosed in Remington's Pharmaceutical Science, Mack Publishing Company, Easton Pa.
Preferably, the treatment or treating mean improving or stabilizing the subject's condition or disease; or preventing or relieving the development or worsening of symptoms associated with the subject's condition or disease. The prevention, prophylaxis and preventive treatment are used herein as synonyms.
Preferably, the treating, preventing, or delaying the onset of, lung cancer may be any one or more of the following: alleviating one or more symptoms of lung cancer, delaying progressing of lung cancer, shrinking tumor size in lung cancer patient, inhibiting tumor growth, prolonging overall survival, prolonging disease-free survival, prolonging time to lung cancer progression, preventing or delaying metastasis, reducing or eradiating preexisting tumor metastasis, reducing incidence or burden of preexisting tumor metastasis, preventing recurrence of lung cancer.
The subject and patient are used herein interchangeably. They refer to a human or another mammal (e.g., mouse, rat, rabbit, dog, cat, cattle, swine, sheep, horse or primate) that can be afflicted with or is susceptible to a disease or disorder but may or may not have the disease or disorder. In certain embodiments, the subject is a human being.
Preferably, the amount effective or effective amount is the amount of an active ingredient or a pharmaceutical composition disclosed herein that when administered to a subject for treating a disease, is sufficient to effect such treatment of the disease. Any improvement in the patient is considered sufficient to achieve treatment. An effective amount of an active ingredient or a pharmaceutical composition disclosed herein, used for the preventing, or delaying the onset of, lung cancer may vary depending upon the manner of administration, the age, body weight, and general health of the patient. Ultimately, the prescribers or researchers will decide the appropriate amount and dosage regimen.
In the treatment or prevention method according to one embodiment disclosed in the present application, the composition including the iCP-SOCS3 recombinant protein as an active ingredient may be administered in a common manner via oral, buccal, rectal, intravenous, intra-arterial, intraperitoneal, intramuscular, intrasternal, percutaneous, topical, intraocular or subcutaneous route, more preferably via intraperitoneal, intravenous, or intra-arterial injection route.
According to one aspect disclosed in the present application, development and establishment of improved cell-permeable SOCS3 recombinant protein, as therapeutics of lung cancer are provided. Because iCP-SOCS3 was designed based on endogenous proteins, it would be a safety anti-lung cancer drug without side-effect.
However, the effects of the disclosures in the present application are not limited to the above-mentioned effects, and another effects not mentioned will be clearly understood by those skilled in the art from the following description.
Previously reported MTDs were selected from a screen of more than 1,500 signal peptide sequences. Although the MTDs that have been developed did not have a common sequence or sequence motif, they were all derived from the hydrophobic (H) regions of signal sequences (HRSSs) that also lack common sequences or motifs except their hydrophobicity and the tendency to adopt alpha-helical conformations. The wide variation in H-region sequences may reflect prior evolution for proteins with membrane translocating activity and subsequent adaptation to the SRP/Sec61 machinery, which utilizes a methionine-rich signal peptide binding pocket in SRP to accommodate a wide-variety of signal peptide sequences.
Previously described hydrophobic CPPs (e.g. MTS/MTM and MTD) were derived from the hydrophobic regions present in the signal peptides of secreted and cell surface proteins. The prior art consists first, of ad hoc use of H-region sequences (MTS/MTM), and second, of H-region sequences (with and without modification) with highest CPP activity selected from a screen of 1,500 signal sequences (MTM). Second prior art, the modified H-region derived hydrophobic CPP sequences had advanced in diversity with multiple number of available sequences apart from MTS/MTM derived from fibroblast growth factor (FGF) 4. However, the number of MTDs that could be modified from naturally occurring secreted proteins are somewhat limited. Because there is no set of rules in determining their cell-permeability, no prediction for the cell-permeability of modified MTD sequences can be made before testing them.
The hydrophobic CPPs, like the signal peptides from which they originated, did not conform to a consensus sequence, and they had adverse effects on protein solubility when incorporated into protein cargo. We therefore set out to identify optimal sequence and structural determinants, namely critical factors (CFs), to design new hydrophobic CPPs with enhanced ability to deliver macromolecule cargoes including proteins into the cells and tissues while maintaining protein solubility. These newly developed CPPs, advanced macromolecule transduction domains (aMTDs) allowed almost infinite number of possible designs that could be designed and developed based on the critical factors. Also, their cell-permeability could be predicted by their character analysis before conducting any in vitro and/or in vivo experiments. These critical factors below have been developed by analyzing all published reference hydrophobic CPPs.
1-1. Analysis of Hydrophobic CPPs
Seventeen different hydrophobic CPPs (Table 1) published from 1995 to 2014 (Table 2) were selected. After physiological and chemical properties of selected hydrophobic CPPs were analyzed, 11 different characteristics that may be associated with cell-permeability have been chosen for further analysis. These 11 characteristics are as follows: sequence, amino acid length, molecular weight, pI value, bending potential, rigidity/flexibility, structural feature, hydropathy, residue structure, amino acid composition and secondary structure of the sequences (Table 3).
Table 1 shows the summary of published hydrophobic Cell-Penetrating Peptides which were chosen.
Homo
sapiens
Homo
sapiens
Streptomyces
coelicolor
Streptomyces
coelicolor
Streptomyces
coelicolor
Homo
sapiens
Drosophila
melanogaster
Homo
sapiens
Phytophthora
cactorum
Streptomyces
coelicolor
Streptomyces
coelicolor
Homo
sapiens
Streptomyces
coelicolor
Streptomyces
coelicolor
Streptomyces
coelicolor
Streptomyces
coelicolor
Neisseria
meningitidis Z2491
Table 2 summarizes reference information
Table 3 shows characteristics of published hydrophobic Cell-Penetrating Peptides (A) which were analyzed.
Two peptide/protein analysis programs were used (ExPasy: SoSui: http://harrier.nagahama-i-bio.ac.jp/sosui/sosui_submit.html) to determine various indexes and structural features of the peptide sequences and to design new sequence. Followings are important factors analyzed.
1-2. Characteristics of Analyzed Peptides: Length, Molecular Weight and pI Value
Average length, molecular weight and pl value of the peptides analyzed were 10.8±2.4, 1,011±189.6 and 5.6±0.1, respectively (Table 4)
Table 4 summarizes Critical Factors (CFs) of published hydrophobic Cell-Penetrating Peptides (A) which were analyzed.
1-3. Characteristics of Analyzed Peptides: Bending Potential—Proline Position (PP)
Bending potential (bending or no-bending) was determined based on the fact whether proline (P) exists and/or where the amino acid(s) providing bending potential to the peptide in recombinant protein is/are located. Proline differs from the other common amino acids in that its side chain is bonded to the backbone nitrogen atom as well as the alpha-carbon atom. The resulting cyclic structure markedly influences protein architecture which is often found in the bends of folded peptide/protein chain.
Eleven out of 17 were determined as ‘Bending’ peptide which means that proline is present in the middle of sequence for peptide bending and/or located at the end of the peptide for protein bending. As indicated above, peptide sequences could penetrate the plasma membrane in a “bent” configuration. Therefore, bending or no-bending potential is considered as one of the critical factors for the improvement of current hydrophobic CPPs.
1-4. Characteristics of Analyzed Peptides: Rigidity/Flexibility—Instability Index (II)
Since one of the crucial structural features of any peptide is based on the fact whether the motif is rigid or flexible, which is an intact physicochemical characteristic of the peptide sequence, instability index (II) of the sequence was determined. The index value representing rigidity/flexibility of the peptide was extremely varied (8.9-79.1), but average value was 40.1±21.9 which suggested that the peptide should be somehow flexible, but not too much rigid or flexible (Table 3).
1-5. Characteristics of Analyzed Peptides: Structural Features—Structural Feature (Aliphatic Index: AI) and Hydropathy (Grand Average of Hydropathy: GRAVY)
Alanine (V), valine (V), leucine (L) and isoleucine (I) contain aliphatic side chain and are hydrophobic—that is, they have an aversion to water and like to cluster. These amino acids having hydrophobicity and aliphatic residue enable them to pack together to form compact structure with few holes. Analyzed peptide sequence showed that all composing amino acids were hydrophobic (A, V, L and I) except glycine (G) in only one out of 17 (MTD10—Table 3) and aliphatic (A, V, L, I, and P). Their hydropathic index (Grand Average of Hydropathy: GRAVY) and aliphatic index (AI) were 2.5±0.4 and 217.9±43.6, respectively. Their amino acid composition is also indicated in the Table 3.
1-6. Characteristics of Analyzed Peptides: Secondary Structure (Helicity)
As explained above, the CPP sequences may be supposed to penetrate the plasma membrane directly after inserting into the membranes in a “bent” configuration with hydrophobic sequences having α-helical conformation. In addition, our analysis strongly indicated that bending potential was crucial for membrane penetration. Therefore, structural analysis of the peptides was conducted to determine whether the sequences were to form helix or not. Nine peptides were helix and eight were not (Table 3). It seems to suggest that helix structure may not be required.
1-7. Determination of Critical Factors (CFs)
In the 11 characteristics analyzed, the following 6 are selected namely “Critical Factors” for the development of new hydrophobic CPPs—advanced MTDs: amino acid length, bending potential (proline presence and location), rigidity/flexibility (instability index: II), structural feature (aliphatic index: AI), hydropathy (GRAVY) and amino acid composition/residue structure (hydrophobic and aliphatic A/a) (Table 3 and Table 4).
Since the analyzed data of the 17 different hydrophobic CPPs (analysis A, Table 3 and 4) previously developed during the past 2 decades showed high variation and were hard to make common—or consensus—features, analysis B (Table 5 and 6) and C (Table 7 and 8) were also conducted to optimize the critical factors for better design of improved CPPs-aMTDs. Therefore, 17 hydrophobic CPPs have been grouped into two groups and analyzed the groups for their characteristics in relation to the cell permeable property. The critical factors have been optimized by comparing and contrasting the analytical data of the groups and determining the common homologous features that may be critical for the cell permeable property.
2-1. Selective Analysis (B) of Peptides Used to Biologically Active Cargo Protein for In Vivo
In analysis B, eight CPPs were used with each biologically active cargo in vivo. Length was 11±3.2, but 3 out of 8 CPPs possessed little bending potential. Rigidity/Flexibility (instability index: II) was 41±15, but removing one [MTD85: rigid, with minimal II (9.1)] of the peptides increased the overall instability index to 45.6±9.3. This suggested that higher flexibility (40 or higher II) is potentially be better. All other characteristics of the 8 CPPs were similar to the analysis A, including structural feature and hydropathy (Table 5 and 6)
Table 5 shows characteristics of published hydrophobic Cell-Penetrating Peptides (B): selected CPPs that were used to each cargo in vivo.
Table 6 shows summarized Critical Factors of published hydrophobic Cell-Penetrating Peptides (B).
2-2. Selective Analysis (C) of Peptides that Provided Bending Potential and Higher Flexibility
To optimize the ‘Common Range and/or Consensus Feature of Critical Factor’ for the practical design of aMTDs and the random peptides (rPs or rPeptides), which were to prove that the ‘Critical Factors’ determined in the analysis A, B and C were correct to improve the current problems of hydrophobic CPPs—protein aggregation, low solubility/yield, and poor cell-/tissue-permeability of the recombinant proteins fused to the MTS/MTM or MTD, and non-common sequence and non-homologous structure of the peptides, empirically selected peptides were analyzed for their structural features and physicochemical factor indexes.
Hydrophobic CPPs which did not have a bending potential, rigid or too much flexible sequences (too much low or too much high Instability Index), or too low or too high hydrophobic CPPs were unselected, but secondary structure was not considered because helix structure of sequence was not required.
In analysis C, eight selected CPP sequences that could provide a bending potential and higher flexibility were finally analyzed (Table 7 and 8). Common amino acid length is 12 (11.6±3.0). Proline is presence in the middle of and/or the end of sequence. Rigidity/Flexibility (II) is 45.5-57.3 (Avg: 50.1±3.6). AI and GRAVY representing structural feature and hydrophobicity of the peptide are 204.7±37.5 and 2.4±0.3, respectively. All peptides are consisted with hydrophobic and aliphatic amino acids (A, V, L, I, and P). Therefore, analysis C was chosen as a standard for the new design of new hydrophobic CPPs-aMTDs.
Table 7 shows characteristics of published hydrophobic Cell-Penetrating Peptides (C): selected CPPs that provided bending potential and higher flexibility.
Table 8 shows summarized Critical Factors of published hydrophobic Cell-Penetrating Peptides (C)
3-1. Determination of Common Sequence and/or Common Homologous Structure
As mentioned above, H-regions of signal sequence (HRSS)-derived CPPs (MTS/MTM and MTD) do not have a common sequence, sequence motif, and/or common-structural homologous feature. In this invention, the aim is to develop improved hydrophobic CPPs formatted in the common sequence- and structural-motif which satisfy newly determined ‘Critical Factors’ to have ‘Common Function,’ namely, to facilitate protein translocation across the membrane with similar mechanism to the analyzed reference CPPs. Based on the analysis A, B and C, the common homologous features have been analyzed to determine the critical factors that influence the cell-permeability. The range value of each critical factor has been determined to include the analyzed index of each critical factor from analysis A, B and C to design novel aMTDs (Table 9). These features have been confirmed experimentally with newly designed aMTDs in their cell-permeability.
Table 9 shows comparison the range/feature of each Critical Factor between the value of analyzed CPPs and the value determined for new design of novel aMTDs sequences
In Table 9, universal common features and sequence/structural motif are provided. Length is 9-13 amino acids, and bending potential is provided with the presence of proline in the middle of sequence (at 5′, 6′, 7′ or 8′ amino acid) for peptide bending and at the end of peptide for recombinant protein bending and Rigidity/Flexibility of aMTDs is II >40 are described in Table 9.
3-2. Critical Factors for Development of Advanced MTDs
Recombinant cell-permeable proteins fused to the hydrophobic CPPs to deliver therapeutically active cargo molecules including proteins into live cells had previously been reported, but the fusion proteins expressed in bacteria system were hard to be purified as a soluble form due to their low solubility and yield. To address the crucial weakness for further clinical development of the cell-permeable proteins as protein-based biotherapeutics, greatly improved form of the hydrophobic CPP, named as advanced MTD (aMTD) has newly been developed through critical factors-based peptide analysis. The critical factors used for the current invention of the aMTDs are herein (Table 9).
1. Amino Acid Length: 9-13
2. Bending Potential (Proline Position: PP)
: Proline presences in the middle (from 5′ to 8′ amino acid) and at the end of sequence
3. Rigidity/Flexibility (Instability Index: II): 40-60
4. Structural Feature (Aliphatic Index: AI): 180-220
5. Hydropathy (GRAVY): 2.1-2.6
6. Amino Acid Composition: Hydrophobic and Aliphatic amino acids—A, V, L, I and P
3-3. Design of Potentially Best aMTDs that all Critical Factors are Considered and Satisfied
After careful consideration of six critical factors derived from analysis of unique features of hydrophobic CPPs, advanced macromolecule transduction domains (aMTDs) have been designed and developed based on the common 12 amino acid platform which satisfies the critical factors including amino acid length (9-13) determined from the analysis.
Unlike previously published hydrophobic CPPs that require numerous experiments to determine their cell-permeability, newly developed aMTD sequences could be designed by performing just few steps as follows using above mentioned platform to follow the determined range value/feature of each critical factor.
First, prepare the 12 amino acid sequence platform for aMTD. Second, place proline (P) in the end (12′) of sequence and determine where to place proline in one of four U(s) in 5′, 6′, 7′, and 8. Third, alanine (A), valine (V), leucine (L) or isoleucine (I) is placed in either X(s) and/or U(s), where proline is not placed. Lastly, determine whether the amino acid sequences designed based on the platform, satisfy the value or feature of six critical factors to assure the cell permeable property of aMTD sequences. Through these processes, numerous novel aMTD sequences have been constructed. The expression vectors for preparing non-functional cargo recombinant proteins fused to each aMTD, expression vectors have been constructed and forcedly expressed in bacterial cells. These aMTD-fused recombinant proteins have been purified in soluble form and determined their cell-permeability quantitatively. aMTD sequences have been newly designed, numbered from 1 to 240, as shown in Table 10-15. In Table 10-15, sequence ID Number is a sequence listings for reference, and aMTD numbers refer to amino acid listing numbers that actually have been used at the experiments. For further experiments, aMTD numbers have been used. In addition, polynucleotide sequences shown in the sequence lists have been numbered from SEQ ID NO: 241 to SEQ ID NO: 480.
Tables 10 to 15 shows 240 new hydrophobic aMTD sequences that were developed to satisfy all critical factors.
3-4. Design of the Peptides that Did not Satisfy at Least One Critical Factor
To demonstrate that this invention of new hydrophobic CPPs-aMTDs, which satisfy all critical factors described above, are correct and rationally designed, the peptides which do not satisfy at least one critical factor have also been designed. Total of 31 rPeptides (rPs) are designed, developed and categorized as follows: no bending peptides, either no proline in the middle as well at the end and/or no central proline; rigid peptides (II<40); too much flexible peptides; aromatic peptides (aromatic ring presences); hydrophobic, with non-aromatic peptides but have amino acids other than A, V, L, I, P or additional proline residues; hydrophilic, but non-aliphatic peptides.
3-4-1. Peptides that do not Satisfy the Bending Potential
Table 16 shows the peptides that do not have any proline in the middle (at 5′, 6′, 7′ or 8′) and at the end of the sequences. In addition, Table 16 describes the peptides that do not have proline in the middle of the sequences. All these peptides are supposed to have no-bending potential.
3-4-2. Peptides that do not Satisfy the Rigidity/Flexibility
To prove that rigidity/flexibility of the sequence is a crucial critical factor, rigid (Avg. II: 21.8±6.6) and too high flexible sequences (Avg. II: 82.3±21.0) were also designed. Rigid peptides that instability index is much lower than that of new aMTDs (II: 41.3-57.3, Avg. II: 53.3±5.7) are shown in Table 17. Bending, but too high flexible peptides that II is much higher than that of new aMTDs are also provided in Table 18.
3-4-3. Peptides that do not Satisfy the Structural Features
New hydrophobic CPPs-aMTDs are consisted with only hydrophobic and aliphatic amino acids (A, V, L, I and P) with average ranges of the indexes—AI: 180-220 and GRAVY: 2.1-2.6 (Table 9). Based on the structural indexes, the peptides which contain an aromatic residue (W, F or Y) are shown in Table 19 and the peptides which are hydrophobic with non-aromatic sequences but have amino acids residue other than A, V, L, I, P or additional proline residues are designed (Table 20). Finally, hydrophilic and/or bending peptides which are consisted with non-aliphatic amino acids are shown in Table 21.
3-5. Summary of Newly Designed Peptides
Total of 457 sequences have been designed based on the critical factors. Designed potentially best aMTDs (hydrophobic, flexible, bending, aliphatic and 12-A/a length peptides) that do satisfy all range/feature of critical factors are 316. Designed rPeptides that do not satisfy at least one of the critical factors are 141 that no bending peptide sequences are 26; rigid peptide (II<40) sequences are 23; too much flexible peptides are 24; aromatic peptides (aromatic ring presences) are 27; hydrophobic, but non-aromatic peptides are 23; and hydrophilic, but non-aliphatic peptides are 18.
4. Preparation of Recombinant Report Proteins Fused to aMTDs and rPeptides
Recombinant proteins fused to aMTDs and others [rPeptides, reference hydrophobic CPP sequences (MTM and MTD)] were expressed in a bacterial system, purified with single-step affinity chromatography and prepared as soluble proteins in physiological condition. These recombinant proteins have been tested for the ability of their cell-permeability by utilizing flow cytometry and laser scanning confocal microscopy.
4-1. Selection of Cargo Protein for Recombinant Proteins Fused to Peptide Sequences
For clinical/non-clinical application, aMTD-fused cargo materials would be biologically active molecules that could be one of the following: enzymes, transcription factors, toxic, antigenic peptides, antibodies and antibody fragments. Furthermore, biologically active molecules could be one of these following macromolecules: enzymes, hormones, carriers, immunoglobulin, membrane-bound proteins, transmembrane proteins, internal proteins, external proteins, secreted proteins, virus proteins, native proteins, glycoproteins, fragmented proteins, disulfide bonded proteins, recombinant proteins, chemically modified proteins and prions. In addition, these biologically active molecules could be one of the following: nucleic acid, coding nucleic acid sequence, mRNAs, antisense RNA molecule, carbohydrate, lipid and glycolipid.
According to these pre-required conditions, a non-functional cargo to evaluate aMTD-mediated protein uptake has been selected and called as Cargo A (CRA) that should be soluble and non-functional. The domain (A/a 289-840; 184 A/a length) is derived from protein S (Genbank ID: CP000113.1).
4-2. Construction of Expression Vector and Preparation of Recombinant Proteins
Coding sequences for recombinant proteins fused to each aMTD are cloned Nde1 (5′) and SalI (3′) in pET-28a(+) (Novagen, Darmstadt, Germany) from PCR-amplified DNA segments. PCR primers for the recombinant proteins fused to aMTD and rPeptides are SEQ ID NOs: 481-797. Structure of the recombinant proteins is displayed in
The recombinant proteins were forcedly expressed in E. coli BL21 (DE3) cells grown to an OD600 of 0.6 and induced for 2 hours with 0.7 mM isopropyl-β-D-thiogalactopyranoside (IPTG). The proteins were purified by Ni2+ affinity chromatography as directed by the supplier (Qiagen, Hilden, Germany) in natural condition. After the purification, purified proteins were dissolved in a physiological buffer such as DMEM medium.
4-3. Expression of aMTD- or Random Peptide (rP)-Fused Recombinant Proteins
Using the standardized six critical factors, 316 aMTD sequences have been designed. In addition, 141 rPeptides are also developed that lack one of these critical factors: no bending peptides: i) absence of proline both in the middle and at the end of sequence or ii) absence of proline either in the middle or at the end of sequence, rigid peptides, too much flexible peptides, aromatic peptides (aromatic ring presence), hydrophobic but non-aromatic peptides, and hydrophilic but non-aliphatic peptides (Table 22).
These rPeptides are devised to be compared and contrasted with aMTDs in order to analyze structure/sequence activity relationship (SAR) of each critical factor with regard to the peptides' intracellular delivery potential. All peptide (aMTD or rPeptide)-containing recombinant proteins have been fused to the CRA to enhance the solubility of the recombinant proteins to be expressed, purified, prepared and analyzed.
These designed 316 aMTDs and 141 rPeptides fused to CRA were all cloned (
To prepare the proteins fused to rPeptides, 60 proteins were expressed that were 10 out of 26 rPeptides in the category of no bending peptides (Table 16); 15 out of 23 in the category of rigid peptides [instability index (II)<40] (Table 17); 19 out of 24 in the category of too much flexible peptides (Table 18); 6 out of 27 in the category of aromatic peptides (Table 19); 8 out of 23 in the category of hydrophobic but non-aromatic peptides (Table 20); and 12 out of 18 in the category of hydrophilic but non-aliphatic peptides (Table 21).
4-4. Quantitative Cell-Permeability of aMTD-Fused Recombinant Proteins
The aMTDs and rPeptides were fluorescently labeled and compared based on the critical factors for cell-permeability by using flow cytometry and confocal laser scanning microscopy (
Table 23 shows Comparison Analysis of Cell-Permeability of aMTDs with a Negative Control (A: rP38).
Relative cell-permeability (relative fold) of aMTDs to the reference CPPs [B: MTM12 (AAVLLPVLLAAP), C: MTD85 (AVALLILAV)] was also analyzed (Tables 40 and 41)
Table 24 shows Comparison Analysis of Cell-Permeability of aMTDs with a Reference CPP (B: MTM12).
Table 25 shows Comparison Analysis of Cell-Permeability of aMTDs with a Reference CPP (C: MTD85).
Geometric means of negative control (histidine-tagged rP38-fused CRA recombinant protein) subtracted by that of naked protein (histidine-tagged CRA protein) lacking any peptide (rP38 or aMTD) was standardized as relative fold of 1. Relative cell-permeability of 240 aMTDs to the negative control (A type) was significantly increased by up to 164 fold, with average increase of 19.6±1.6 (Table 26-31).
Moreover, compared to reference CPPs (B type: MTM12 and C type: MTD85), novel 240 aMTDs averaged of 13±1.1 (maximum 109.9) and 6.6±0.5 (maximum 55.5) fold higher cell-permeability, respectively (Tables 26-31).
In addition, cell-permeability of 31 rPeptides has been compared with that of 240 aMTDs (0.3±0.04; Tables 32 and 33).
In summary, relative cell-permeability of aMTDs has shown maximum of 164.0, 109.9 and 55.5 fold higher to rP38, MTM12 and MTD85, respectively. In average of total 240 aMTD sequences, 19.6±1.6, 13.1±1.1 and 6.6±0.5 fold higher cell-permeability are shown to the rP38, MTM12 and MTD85, respectively (Tables 26-31). Relative cell-permeability of negative control (rP38) to the 240 aMTDs is only 0.3±0.04 fold.
4-5. Intracellular Delivery and Localization of aMTD-Fused Recombinant Proteins
Recombinant proteins fused to the aMTDs were tested to determine their intracellular delivery and localization by laser scanning confocal microscopy with a negative control (rP38) and previous published CPPs (MTM12 and MTD85) as the positive control references. NIH3T3 cells were exposed to 10 μM of FITC-labeled protein for 1 hour at 37, and nuclei were counterstained with DAPI. Then, cells were examined by confocal laser scanning microscopy (
4-6. Summary of Quantitative and Visual Cell-Permeability of Newly Developed aMTDs
Histidine-tagged aMTD-fused cargo recombinant proteins have been greatly enhanced in their solubility and yield. Thus, FITC-conjugated recombinant proteins have also been tested to quantitate and visualize intracellular localization of the proteins and demonstrated higher cell-permeability compared to the reference CPPs.
In the previous studies using the hydrophobic signal-sequence-derived CPPs-MTS/MTM or MTDs, 17 published sequences have been identified and analyzed in various characteristics such as length, molecular weight, pI value, bending potential, rigidity, flexibility, structural feature, hydropathy, amino acid residue and composition, and secondary structure of the peptides. Based on these analytical data of the sequences, novel artificial and non-natural peptide sequences designated as advanced MTDs (aMTDs) have been invented and determined their functional activity in intracellular delivery potential with aMTD-fused recombinant proteins.
aMTD-fused recombinant proteins have promoted the ability of protein transduction into the cells compared to the recombinant proteins containing rPeptides and/or reference hydrophobic CPPs (MTM12 and MTD85). According to the results, it has been demonstrated that critical factors of cell-penetrating peptide sequences play a major role to determine peptide-mediated intracellular delivery by penetrating plasma membrane. In addition, cell-permeability can considerably be improved by following the rational that all satisfy the critical factors.
5. Structure/Sequence Activity Relationship (SAR) of aMTDs on Delivery Potential
After determining the cell-permeability of novel aMTDs, structure/sequence activity relationship (SAR) has been analyzed for each critical factor in selected some of and all of novel aMTDs (
5-1. Proline Position:
In regards to the bending potential (proline position: PP), aMTDs with its proline at 7′ or 8′ amino acid in their sequences have much higher cell-permeability compared to the sequences in which their proline position is at 5′ or 6′ (
5-2. Hydropathy:
In addition, when the aMTDs have GRAVY (Grand Average of Hydropathy) ranging in 2.1-2.2, these sequences display relatively lower cell-permeability, while the aMTDs with 2.3-2.6 GRAVY are shown significantly higher one (
5-3. rPeptide SAR:
To the SAR of aMTDs, rPeptides have shown similar SAR correlations in the cell-permeability, pertaining to their proline position (PP) and hydropathy (GRAVY). These results confirms that rPeptides with high GRAVY (2.4-2.6) have better cell-permeability (
5-4. Analysis of Amino Acid Composition:
In addition to proline position and hydropathy, the difference of amino acid composition is also analyzed. Since aMTDs are designed based on critical factors, each aMTD-fused recombinant protein has equally two proline sequences in the composition. Other hydrophobic and aliphatic amino acids—alanine, isoleucine, leucine and valine—are combined to form the rest of aMTD peptide sequences.
Alanine: In the composition of amino acids, the result does not show a significant difference by the number of alanine in terms of the aMTD's delivery potential because all of the aMTDs have three to five alanines. In the sequences, however, four alanine compositions show the most effective delivery potential (geometric mean) (
Leucine and Isoleucine: Also, the compositions of isoleucine and leucine in the aMTD sequences show inverse relationship between the number of amino acid (I and L) and delivery potential of aMTDs. Lower number of isoleucine and leucine in the sequences tends to have higher delivery potential (geometric mean) (
Valine: Conversely, the composition of valine of aMTD sequences shows positive correlation with their cell-permeability. When the number of valine in the sequence is low, the delivery potential of aMTD is also relatively low (
Ten aMTDs having the highest cell-permeability are selected (average geometric mean: 2584±126). Their average number of valine in the sequences is 3.5; 10 aMTDs having relatively low cell-permeability (average geometric mean: 80±4) had average of 1.9 valine amino acids. The average number of valine in the sequences is lowered as their cell-permeability is also lowered as shown in
5-5. Conclusion of SAR Analysis:
As seen in
The range and feature of five out of six critical factors have been empirically and experimentally determined that are also included in the index range and feature of the critical factors initially proposed before conducting the experiments and SAR analysis. In terms of index range and feature of critical factors of newly developed 240 aMTDs, the bending potential (proline position: PP), rigidity/flexibility (Instability Index: II), structural feature (Aliphatic Index: AI), hydropathy (GRAVY), amino acid length and composition are all within the characteristics of the critical factors derived from analysis of reference hydrophobic CPPs.
Therefore, our hypothesis to design and develop new hydrophobic CPP sequences as advanced MTDs is empirically and experimentally proved and demonstrated that critical factor-based new aMTD rational design is correct.
7. Discovery and Development of Protein-Based New Biotherapeutics with MITT Enabled by aMTDs for Protein Therapy
Total of 240 aMTD sequences have been designed and developed based on the critical factors. Quantitative and visual cell-permeability of 240 aMTDs (hydrophobic, flexible, bending, aliphatic and 12 a/a-length peptides) are all practically determined.
To measure the cell-permeability of aMTDs, rPeptides have also been designed and tested. As seen in
These examined critical factors are within the range that we have set for our critical factors; therefore, we are able to confirm that the aMTDs that satisfy these critical factors have relatively high cell-permeability and much higher intracellular delivery potential compared to reference hydrophobic CPPs reported during the past two decades.
It has been widely evident that many human diseases are caused by proteins with deficiency or over-expression that causes mutations such as gain-of-function or loss-of-function. If biologically active proteins could be delivered for replacing abnormal proteins within a short time frame, possibly within an hour or two, in a quantitative manner, the dosage may be regulated depending on when and how proteins may be needed. By significantly improving the solubility and yield of novel aMTD in this invention (Table 31), one could expect its practical potential as an agent to effectively deliver therapeutic macromolecules such as proteins, peptides, nucleic acids, and other chemical compounds into live cells as well as live mammals including human. Therefore, newly developed MITT utilizing the pool (240) of novel aMTDs can be used as a platform technology for discovery and development of protein-based biotherapeutics to apprehend intracellular protein therapy after determining the optimal cargo-aMTD relationship.
The following examples are presented to aid practitioners of the invention, to provide experimental support for the invention, and to provide model protocols. In no way are these examples to be understood to limit the invention.
H-regions of signal sequences (HRSP)-derived CPPs (MTS/MTM and MTD) do not have a common sequence, a sequence motif, and/or a common structural homologous feature. In this invention, the aim is to develop improved hydrophobic CPPs formatted in the common sequence and structural motif that satisfy newly determined ‘critical factors’ to have a ‘common function,’ to facilitate protein translocation across the plasma membrane with similar mechanism to the analyzed CPPs.
The structural motif as follows:
In Table 9, universal common sequence/structural motif is provided as follows. The amino acid length of the peptides in this invention ranges from 9 to 13 amino acids, mostly 12 amino acids, and their bending potentials are dependent with the presence and location of proline in the middle of sequence (at 5′, 6′, 7′ or 8′ amino acid) and at the end of peptide (at 12′) for recombinant protein bending. Instability index (II) for rigidity/flexibility of aMTDs is 11<40, grand average of hydropathy (GRAVY) for hydropathy is around 2.2, and aliphatic index (AI) for structural features is around 200 (Table 9). Based on these standardized critical factors, new hydrophobic peptide sequences, namely advanced macromolecule transduction domain peptides (aMTDs), in this invention have been developed and summarized in Tables 10 to 15.
Our newly developed technology has enabled us to expand the method for making cell-permeable recombinant proteins. The expression vectors were designed for histidine-tagged CRA proteins fused with aMTDs or rPeptides. To construct expression vectors for recombinant proteins, polymerase chain reaction (PCR) had been devised to amplify each designed aMTD or rPeptide fused to CRA.
The PCR reactions (100 ng genomic DNA, 10 pmol each primer, each 0.2 mM dNTP mixture, 1× reaction buffer and 2.5 U Pfu(+) DNA polymerase (Doctor protein, Korea) was digested on the restriction enzyme site between Nde I (5′) and Sal I (3′) involving 35 cycles of denaturation (95° C.), annealing (62° C.), and extension (72° C.) for 30 seconds each. For the last extension cycle, the PCR reactions remained for 5 minutes at 72° C. Then, they were cloned into the site of pET-28a(+) vectors (Novagen, Darmstadt, Germany). DNA ligation was performed using T4 DNA ligase at 4° C. overnight. These plasmids were mixed with competent cells of E. coli DH5-alpha strain on the ice for 10 minutes. This mixture was placed on the ice for 2 minutes after it was heat shocked in the water bath at 42° C. for 90 seconds. Then, the mixture added with LB broth media was recovered in 37° C. shaking incubator for 1 hour. Transformant was plated on LB broth agar plate with kanamycin (50 μg/mL) (Biopure, Johnson City, Tenn., USA) before incubating at 37° C. overnight. From a single colony, plasmid DNA was extracted, and after the digestion of Nde I and Sal I restriction enzymes, digested DNA was confirmed at 645 bp by using 1.2% agarose gels electrophoresis (
To express recombinant proteins, pET-28a(+) vectors for the expression of CRA proteins fused to a negative control [rPeptide 38 (rP38)], reference hydrophobic CPPs (MTM12 and MTD85) and aMTDs were transformed in E. coli BL21 (DE3) strains. Cells were grown at 37° C. in LB medium containing kanamycin (50 μg/ml) with a vigorous shaking and induced at OD600=0.6 by adding 0.7 mM IPTG (Biopure) for 2 hours at 37° C. Induced recombinant proteins were loaded on 15% SDS-PAGE gel and stained with Coomassie Brilliant Blue (InstantBlue, Expedeon, Novexin, UK) (
The E. coli cultures were harvested by centrifugation at 5,000×rpm for 10 minutes, and the supernatant was discarded. The pellet was re-suspended in the lysis buffer (50 mM NaH2PO4, 10 mM Imidazol, 300 mM NaCl, pH 8.0). The cell lysates were sonicated on ice using a sonicator (Sonics and Materials, Inc., Newtown, Conn., USA) equipped with a probe. After centrifuging the cell lysates at 5,000×rpm for 10 minutes to pellet the cellular debris, the supernatant was incubated with lysis buffer-equilibrated Ni-NTA resin (Qiagen, Hilden, Germany) gently by open-column system (Bio-rad, Hercules, Calif., USA). After washing protein-bound resin with 200 ml wash buffer (50 mM NaH2PO4, 20 mM Imidazol, 300 mM NaCl, pH 8.0), the bounded proteins were eluted with elution buffer (50 mM NaH2PO4, 250 mM Imidazol, 300 mM NaCl, pH 8.0).
Recombinant proteins purified under natural condition were analyzed on 15% SDS-PAGE gel and stained with Coomassie Brilliant Blue (
For quantitative cell-permeability, the aMTD- or rPeptide-fused recombinant proteins were conjugated to fluorescein isothiocyanate (FITC) according to the manufacturer's instructions (Sigma-Aldrich, St. Louis, Mo., USA). RAW 264.7 cells were treated with 10 μM FITC-labeled recombinant proteins for 1 hour at 37° C., washed three times with cold PBS, treated with 0.25% tripsin/EDTA (Sigma-Aldrich, St. Louis, Mo.) for 20 minutes at 37° C. to remove cell-surface bound proteins. Cell-permeability of these recombinant proteins were analyzed by flow cytometry (Guava, Millipore, Darmstadt, Germany) using the FlowJo cytometric analysis software (
For a visual reference of cell-permeability, NIH3T3 cells were cultured for 24 hours on coverslip in 24-wells chamber slides, treated with 10 μM FITC-conjugated recombinant proteins for 1 hour at 37° C., and washed three times with cold PBS. Treated cells were fixed in 4% paraformaldehyde (PFA, Junsei, Tokyo, Japan) for 10 minutes at room temperature, washed three times with PBS, and mounted with VECTASHIELD Mounting Medium (Vector laboratories, Burlingame, Calif., USA), and counter stained with DAPI (4′,6-diamidino-2-phenylindole). The intracellular localization of the fluorescent signal was determined by confocal laser scanning microscopy (LSM700, Zeiss, Germany;
Full-length cDNA for human SOCS3 (SEQ ID NO: 815) was purchased from Origene (USA). Histidine-tagged human SOCS3 proteins were constructed by amplifying the SOCS3 cDNA (225 amino acids) using primers for aMTD fused to SOCS3 cargo. The PCR reactions (100 ng genomic DNA, 10 pmol each primer, each 0.2 mM dNTP mixture, 1× reaction buffer and 2.5 U Pfu(+) DNA polymerase (Doctor protein, Korea)) were digested on the restriction enzyme site between Nde I (5′) and Sal I (3′) involving 35 cycles of denaturing (95° C.), annealing (62° C.), and extending (72° C.) for 45 sec each. For the last extension cycle, the PCR reactions remained for 10 min at 72° C. The PCR products were subcloned into 6×His expression vector, pET-28a(+) (Novagen, Darmstadt, Germany). Coding sequence for SDA or SDB fused to C terminus of his-tagged aMTD-SOCS3 was cloned at BamHI (5′) and SalI (3′) in pET-28a(+) from PCR-amplified DNA segments and confirmed by DNA sequence analysis of the resulting plasmids.
To determine a stable structure of the cell-permeable aMTD/SD-fused SOCS3 recombinant protein, a pET-28a(+) vector and an E. coli BL21-CodonPlus (DE3)-RIL were subjected to the following experiment.
Each of the recombinant expression vectors, HS3, HMS3, HMS3A, HMS3B, HMS3C, HMS3D, and HMS3E prepared in example 6-1 was transformed into E. coli BL21 CodonPlus(DE3)-RIL by a heat shock method, and then 600 ul of each was incubated in an LB medium (Biopure, Johnson City, Tenn., USA) containing 50 μg/ml of kanamycin at 37° C. for 1 hour. Thereafter, the recombinant protein gene-introduced E. coli was inoculated in 7 ml of LB medium, and then incubated at 37° C. overnight. The E. coli was inoculated in 700 ml of LB medium and incubated at 37° C. until OD600 reached 0.6. To this culture medium, 0.6 mM of isopropyl-β-D-thiogalactoside (IPTG, Gen Depot, USA) was added as a protein expression inducer, followed by further incubation at 37° C. for 3 hours. This culture medium was centrifuged at 4° C. and 8,000 rpm for 10 minutes and a supernatant was discarded to recover a cell pellet. The cell pellet thus recovered was suspended in a lysis buffer (100 mM NaH2PO4, 10 mM Tris-HCl, 8 M Urea, pH 8.0), and cells were disrupted by sonication (on/off time: 30 sec/30 sec, on time 2 hours, amplify 40%), and centrifuged at 15,000 rpm for 30 min to obtain a soluble fraction and an insoluble fraction.
This insoluble fraction was suspended in a denature lysis buffer (8 M Urea, 10 mM Tris, 100 mM Sodium phosphate) and purified by Ni2+ affinity chromatography as directed by the supplier(Qiagen, Hilden, Germany) and refolded by dialyzing with a refolding buffer (0.55 M guanidine HCl, 0.44 M L-arginine, 50 mM Tris-HCl, 150 mM NaCl, 1 mM EDTA, 100 mM NDSB, 2 mM reduced glutathione, and 0.2 mM oxidized glutathione). After purification, the proteins were put in a SnakeSkin Dialysis Tubing bag (pore size: 10000 mw, Thermo scientific, USA) and then they were dialyzed by physiological buffer (DMEM). The strain lysate where protein expression was not induced, the strain lysate where protein expression was induced by addition of IPTG, and purified proteins were loaded on SDS-PAGE to analyze protein expression characteristics and expression levels (
As shown in
To determine aMTD/SD-fused SOCS3 recombinant proteins having optimal cell-permeability, solubilization domains were replaced in the same manner as in Example 6-2 to prepare 5 kinds of aMTD/SD-fused SOCS3 recombinant proteins, and their solubility/yield were measured (
As shown in
To compare the solubility/yield, cell/tissue-permeability, mechanism of cytopermeability of aMTD/SD-fused SOCS3 recombinant proteins to those of conventional basic CPP/SD-fused SOCS3 recombinant proteins, cloning, preparation, and measurement of solubility/yield of the basic CPP/SD-fused SOCS3 recombinant proteins were performed in the same manner as in Examples 6-1 to 6-3 except for a known basic CPP (TAT or PolyR) being used instead of aMTD. Sequences of amino acids and nucleotides of basic CPP, and the primers used in this example are shown in
The solubility/yield of aMTD165/SD-fused SOCS3 recombinant proteins was much higher than that of TAT/SD-fused SOCS3 or PolyR/SD-fused SOCS3 recombinant proteins (
To examine cell-permeability of SOCS3 recombinant protein, SOCS3 recombinant proteins were conjugated to 5/6-fluorescein isothiocyanate (FITC). RAW 264.7 (KCLB, Seoul, South Korea) (
In this regard, RAW 264.7 cells were cultured in a DMEM medium containing 10% fetal bovine serum (FBS, Hyclone, USA) and 500 mg/ml of 1% penicillin/streptomycin (Hyclone, USA).
After cultivation, the cells were washed three times with ice-cold PBS (Phosphate-buffered saline, Hyclone, USA) and treated with proteinase K (10 μg/mL, SIGMA, USA) to remove surface-bound proteins, and internalized proteins were measured by flow cytometry (FlowJo cytometric analysis software, Guava, Millipore, Darmstadt, Germany). Untreated cells (gray) and equimolar concentration of unconjugated FITC (FITC only, green)-treated cells were served as control (
As shown in
The cell-permeability of basic CPP/SD-fused SOCS3 recombinant proteins was assessed by the same method as used in Example 7-1 except for a known basic CPP (TAT or PolyR) being used instead of aMTD. The results of the assessment were shown in
According to the results, all recombinant proteins exhibited cell-permeability. Among the proteins, aMTD/SD-fused SOCS3 recombinant protein (HM165S3B) showed the highest cell-permeability.
To further investigate in vivo delivery of SOCS3 recombinant proteins, ICR mice (Doo-Yeol Biotech Co. Ltd., Seoul, Korea) were intraperitoneal (IP) injected with 600 μg/head of 10 μM FITC (Fluorescein isothiocyanate, SIGMA, USA)-labeled SOCS3 proteins and sacrificed after 2 hrs. From the mice, the liver, kidney, spleen, lung, heart, and brain were removed and washed with PBS, and then placed on a dry ice, and embedded with an O.C.T. compound (Sakura). After cryosectioning at 20 μm, tissue distributions of fluorescence-labeled-SOCS3 proteins in different organs was analyzed by fluorescence microscopy (Carl Zeiss, Gottingen, Germany) (
As shown in
The tissue-permeability of basic CPP/SD-fused SOCS3 recombinant proteins was assessed by the same method as used in Example 7-2 except for a known basic CPP (TAT or PolyR) being used instead of aMTD. The results of the assessment were shown in
According to the results, only aMTD/SD-fused SOCS3 recombinant protein (HM165S3B) exhibited superior cell-permeability.
It was examined whether the iCP-SOCS3 recombinant proteins prepared by fusion with combinations of aMTD and SD inhibits activation of the JAK/STAT-signaling pathway.
PANC-1 Cells (KCLB, Seoul, South Korea) were treated with 10 ng/ml IFN-γ (R&D systems, Abingdon, UK) for 15 min and treated with either DMEM (vehicle) or 10 μM aMTD/SD-fused SOCS3 recombinant proteins for 2 hrs. The cells were lysed in RIPA lysis buffer (Biosesang, Seongnam, Korea) containing proteinase inhibitor cocktail (Roche, Indianapolis, Ind., USA), incubated for 15 min at 4° C., and centrifuged at 13,000 rpm for 10 min at 4° C. Equal amounts of lysates were separated on 10% SDS-PAGE gels and transferred to a nitrocellulose membrane. The membranes were blocked using 5% skim milk in TBST and for western blot analysis incubated with the following antibodies: anti-phospho-STAT1 (Cell Signaling Technology, USA) and anti-phospho-STAT3 (Cell Signaling Technology, USA), then HRP conjugated anti-rabbit secondary antibody (Santacruz).
The well-known cytokine signaling inhibitory actions of SOCS3 are inflammation inhibition through i) inhibition of IFN-γ-mediated JAK/STAT and ii) inhibition of LPS-mediated cytokine secretion. The ultimate test of cell-penetrating efficiency is a determination of intracellular activity of SOCS3 proteins transported by aMTD. Since endogenous SOCS3 are known to block phosphorylation of STAT1 and STAT3 by IFN-γ-mediated Janus kinases (JAK) 1 and 2 activation, we demonstrated whether cell-permeable SOCS3 inhibits the phosphorylation of STATs. As shown in
Peritoneal macrophages were obtained from C3H/HeJ mice (Doo-Yeol Biotech Co. Ltd. Korea) Peritoneal macrophages were incubated with 10 μM SOCS3 recombinant proteins (1:HS3, 2:HM165S3, 3:HM165S3A and 4:HM165S3B, respectively) for 1 hr at 37° C. and then stimulated them with LPS (Lipopolysaccharide)(500 ng/ml) and/or IFN-γ (100 U/ml) without removing iCP-SOCS3 proteins for 3, 6, or 9 hrs. The culture media were collected, and the extracellular levels of cytokine (TNF-α, IL-6) were measured by a cytometric bead array (BD Pharmingen, San Diego, Calif., USA) according to the manufacturer's instructions.
The effect of cell-permeable SOCS3 proteins on cytokines secretion was investigated. Treatment of C3H/HeJ primary peritoneal macrophages with SOCS3 proteins containing aMTD165 suppressed TNF-α and IL-6 secretion induced by the combination of IFN-γ and LPS by 50-90% during subsequent 9 hrs of incubation (
As an experimental negative control, a SOCS3 recombinant protein having no cell permeability was prepared.
According to example 6-2, SOCS3 recombinant proteins lacking SD (HM165S3) or both aMTD and SD (HS3) were found to be less soluble, produced lower yields, and showed tendency to precipitate when they were expressed and purified in E. coli. Therefore, we additionally designed and constructed SOCS3 recombinant protein containing only SDB (without aMTD165: HS3B) as a negative control (
As expected, its solubility and yield increased compared to that of SOCS3 proteins lacking SDB (HS3;
After a basic structure of the stable recombinant proteins fused with combinations of aMTD and SD was determined, 22 aMTDs were selected for development of iCP-SOCS3 recombinant protein (Tables 38 and 39), based on the critical Factors, in order to examine which aMTD provides the highest cell-/tissue-permeability.
For comparison, 5 kinds of random peptides that do not satisfying one or more critical factors were selected (Table 40).
Solubility/yield and cell-permeability of 22 kinds of aMTD/SDB-fused SOCS3 recombinant proteins, prepared by using primers of Table 41 in the same manner as in Example 6-2, were analyzed according to examples 6-3 and 7-1, respectively.
As shown in
Four kinds of aMTD/SD-fused SOCS3 recombinant proteins having high cell permeability and one kind of aMTD/SD-fused SOCS3 recombinant protein having the lowest cell permeability were selected, and their biological activity was analyzed.
PANC-1 cells (pancreatic carcinoma cell line) were seeded in a 16-well chamber slide at a density of 5×103 cells/well, and then treated with 10 uM of aMTD/SD-fused SOCS3 for 24 hours. Apoptotic cells were analyzed using terminal dUTP nick-end labeling (TUNEL) assay with In Situ Cell Death Detection kit TMR red (Roche, 4056 Basel, Switzerland). Cells were treated with either 10 μM SOCS3 recombinant protein or buffer alone for 16 hrs with 2% fetal bovine serum (Hyclone, Logan, Utah, USA). Treated cells were washed with cold PBS two times, fixed in 4% paraformaldehyde (PFA, Junsei, Tokyo, Japan) for 1 hr at room temperature, and incubated in 0.1% Triton X-100 for 2 min on the ice. Cells were washed with cold PBS twice, and treated TUNEL reaction mixture for 1 hr at 37° C. in dark, washed cold PBS three times and observed by fluorescence microscopy (Nikon, Tokyo, Japan).
As shown in
AGS cells (gastric carcinoma cell line) (American Type Culture Collection; ATCC) were seeded in a 12-well plate at a density of 1×105 cells/well, and then treated with 10 uM of aMTD/SD-fused SOCS3 for 14 hours. Cancer cell death was analyzed by Annexin V analysis. Annexin V/7-Aminoactinomycin D (7-AAD) staining was performed using flow cytometry according to the manufacturer's guidelines (BD Pharmingen, San Diego, Calif., USA). Briefly, cells were washed three times with ice-cold PBS. The cells were then resuspended in 100 μl of binding buffer and incubated with 1 μl of 7-AAD and 1 μl of annexin V-PE for 30 min in the dark at 37° C. Flow cytometric analysis was immediately performed using a guava easyCyte™ 8 Instrument (Merck Millipore, Darmstadt, Germany).
As shown in
AGS cells (gastric cancer cell line) were seeded in a 12 well plate at a density of 2.5×105 per well, grown to 90% confluence. Confluent AGS cells were incubated with 10 μM HM#S3B in serum-free medium for 2 hrs prior to changing the growth medium (DMEM/F12, Hyclone, Logan, Utah, USA) and washed twice with PBS, and the monolayer at the center of the well was “wounded” by scraping with a sterilized white pipette tip. Cells were cultured for an additional 24 hrs and cell migration was observed by phase contrast microscopy (Nikon, ECLIPSE Ts2). The migration was quantified by counting the number of cells that migrated from the wound edge into the clear area.
As shown in
Solubility/yield, permeability, and biological activity of 22 kinds of the aMTD-fused recombinant proteins were examined in Examples 10 to 11-3, and as a result, the aMTD165/SDB-fused SOCS3 recombinant protein was found to show the most excellent effect (
To develop a new drug as an anticancer agent, His-tag-removed iCP-SOCS3 recombinant protein was prepared and equivalence of His-Tag+, −iCP-SOCS3 was investigated.
Histidine-tag free human SOCS3 proteins were constructed by amplifying the SOCS3 cDNA (225 amino acids) for aMTD fused to SOCS3 cargo. The PCR reactions (100 ng genomic DNA, 10 pmol each primer, each 0.2 mM dNTP mixture, 1× reaction buffer and 2.5 U Pfu(+) DNA polymerase (Doctor protein, Korea)) were digested on the restriction enzyme site between Nde I (5′) and Sal I (3′) involving 35 cycles of denaturing (95° C.), annealing (62° C.), and extending (72° C.) for 45 sec each. For the last extension cycle, the PCR reactions remained for 10 min at 72° C. The PCR products were subcloned into pET-26b(+) (Novagen, Darmstadt, Germany). Coding sequence for SDB fused to C terminus of aMTD-SOCS3 was cloned at BamHI (5′) and SalI (3′) in pET-26b(+) from PCR-amplified DNA segments and confirmed by DNA sequence analysis of the resulting plasmids.
Expression, purification and solubility/yield were measured in the same manner as in Examples 6-2 and 6-3, and as a result, his-tag-removed M165S3B was found to have high solubility/yield (
In the same manner as in Example 7-1, RAW264.7 cells were treated with FITC-labeled HS3B, HM165S3B, and M165S3B proteins, and cell permeability was evaluated.
As shown in
To investigate biological activity equivalence of the HM165S3B and M165S3B recombinant proteins, induction of apoptosis of gastric carcinoma cell line (AGS) was analyzed by Annexin V staining in the same manner as in Example 11-2, and inhibition of migration was analyzed in the same manner as in Example 11-3.
As shown in
In silico MHC class II binding analysis using iTope™ (ANTITOPE.LTD) revealed changing the V28 p1 anchor residue in SDB sequence to L makes this region human germline and as such both MHC class II binding peptides within this region would be expected to be low risk due to T cell tolerance.
To prepare humanized SDB domain, iCP-SOCS3 was prepared as in
As shown in
In the same manner as in Example 7-1, RAW264.7 cells were treated with FITC-labeled HM165S3B and HM165S3B′(V28L) proteins, and cell permeability was evaluated.
As shown in
To investigate biological activity equivalence of the HM165S3B and HM165S3B′(V28L) recombinant proteins, anti-proliferative activity was examined and induction of apoptosis of gastric carcinoma cell line (AGS) was analyzed by Annexin V staining in the same manner as in Example 11-2, and inhibition of migration was analyzed in the same manner as in Example 11-3.
Antiproliferative activity were evaluated with the CellTiter-Glo Cell Viability Assay. AGS cells (3×103/well) were seeded in 96 well plates. The next day, cells were treated with DMEM (vehicle) or 10 μM HM165S3B, HM165S3B′(V28L) for 96 hrs in the presence of serum (2%). Proteins were replaced daily. Cell growth and survival were evaluated with the CellTiter-Glo Cell Viability Assay (Promega, Madison, Wis.). Measurements using a Luminometer (Turner Designs, Sunnyvale, Calif.) were conducted following the manufacturer's protocol.
It was confirmed that both HM165S3B and HM165S3B′(V28L) showed high anti-proliferative effects on gastric carcinoma cells (
iCP-SOCS3 of BS3M165 structure was prepared in the same manner as in Example 6-1, and B′S3M165 iCP-SOCS3 was also prepared by humanized SDB domain (
Expressions and purifications of iCP-SOCS3 recombinant protein (BS3M165, B′S3M165) in E. coli (bottom) were analyzed in the same manner as in Examples 6-2 and 6-3, respectively, and were shown in
Whether iCP-SOCS3 (HM165S3B) recombinant protein inhibits activation of the JAK/STAT-signaling pathway was examined by the method of Example 8-1.
PANC-1 Cells (KCLB, Seoul, South Korea) were treated with 10 ng/ml IFN-γ (R&D systems, Abingdon, UK) for 15 min and treated with either DMEM (vehicle) or 1, 5, 10 μM aMTD/SD-fused SOCS3 recombinant proteins for 2 hrs. The cells were lysed in RIPA lysis buffer (Biosesang, Seongnam, Korea) containing proteinase inhibitor cocktail (Roche, Indianapolis, Ind., USA), incubated for 15 min at 4° C., and centrifuged at 13,000 rpm for 10 min at 4° C. Equal amounts of lysates were separated on 10% SDS-PAGE gels and transferred to a nitrocellulose membrane. The membranes were blocked using 5% skim milk in TBST and for western blot analysis incubated with the following antibodies: anti-phospho-STAT3 (Cell Signaling Technology, USA), then HRP conjugated anti-rabbit secondary antibody (Santacruz).
The well-known cytokine signaling inhibitory actions of SOCS3 are inflammation inhibition through i) inhibition of IFN-γ-mediated JAK/STAT and ii) inhibition of LPS-mediated cytokine secretion. The ultimate test of cell-penetrating efficiency is a determination of intracellular activity of SOCS3 proteins transported by aMTD. Since endogenous SOCS3 are known to block phosphorylation of STAT3 by IFN-γ-mediated Janus kinases (JAK) 1 and 2 activation, we demonstrated whether cell-permeable SOCS3 inhibits the phosphorylation of STATs. As shown in
The mechanism of aMTD165-mediated intracellular delivery was investigated.
(1) RAW 264.7 cells were pretreated with 100 mM EDTA for 3 hours, and then treated with 10 uM of iCP-SOCS3 (HM165S3B) protein for 1 hour, followed by flow cytometry in the same manner as in Example 7-1 (
(2) RAW 264.7 cells were pretreated with 5 ug/ml of proteinase K for 10 minutes, and then treated with 10 uM of iCP-SOCS3 (HM165S3B) protein for 1 hour, followed by flow cytometry (
(3) RAW 264.7 cells were pretreated with 20 uM taxol for 30 minutes, and then treated with 10 uM of iCP-SOCS3 (HM165S3B) protein for 1 hour, followed by flow cytometry (
(4) RAW 264.7 cells were pretreated with 1 mM ATP and 10 uM antimycin singly or in combination for 2 hours, and then treated with 10 uM of iCP-SOCS3 (HM165S3B) protein for 1 hour, followed by flow cytometry (
(5) RAW 264.7 cells were left at 4° C. and 37° C. for 1 hour, respectively, and then treated with 10 uM of iCP-SOCS3 (HM165S3B) protein for 1 hour, followed by flow cytometry (FIG. 53).
The aMTD-mediated intracellular delivery of SOCS3 protein did not require protease-sensitive protein domains displayed on the cell surface (
Moreover, whether cells treated with iCP-SOCS3 (HM165S3B) protein could transfer the protein to neighboring cells were also tested.
For this, RAW 264.7 cells were treated with 10 uM of FITC-labeled iCP-SOCS3 (HM165S3B) protein for 1 hour. Thereafter, these cells were co-cultured with PerCP-Cy5.5-CD14-stained RAW 264.7 cells for 2 hours. Cell-to-cell protein transfer was assessed by flow cytometry, scoring for CD14/FITC double-positive cells. Efficient cell-to-cell transfer of HM165S3B, but not HS3 or HS3B (
The mechanism of basic CPP (TAT and PolyR)-mediated intracellular delivery was also investigated in the same manner as in Example 7-1 and Example 14-1.
As shown in
Whether cells treated with aMTD165/SD-fused SOCS3, TAT/SD-fused SOCS3, and PolyR/SD-fused SOCS3 could transfer the protein to neighboring cells were also tested on a molecular level in the same manner as in Example 13.
For this, RAW 264.7 cells were treated with 5 μM of FITC-labeled HM165S3B, HTS3B for 2 hour and washed with PBS two times. Thereafter, they were seeded on PANC-1 cell, incubated for 2 hours and treated with 20 ng/ml of IFN-γ for 15 minutes, followed by Western blotting in the same manner as in Example 8-1. And Cell-to-cell protein transfer was assessed by flow cytometry.
As shown in
Moreover, as shown in
It was examined whether the cell-permeability of iCP-SOCS3 recombinant protein is dose-dependent. Cell-permeability of iCP-SOCS3 recombinant protein was tested in the same manner as in Example 7-1 except for the cells being treated with 0.05 μM-10 μM of iCP-SOCS3 recombinant protein for 1 hrs. As shown in
Time-dependency of cell-permeability was also investigated. The cells were treated with 10 μM of iCP-SOCS3 recombinant protein for 5˜180 minutes. As shown in
To investigate BA of the iCP-SOCS3 (HM165S3B) recombinant proteins, ICR mice (Doo-Yeol Biotech Co. Ltd., Seoul, Korea) were intravenous (IV) injected with 600 μg/head of 10 μM FITC (Fluorescein isothiocyanate, SIGMA, USA)-labeled SOCS3 recombinant proteins (HS3B, HM165S3B) and after 15 min, 30 min, 1 H, 2 H, 4 H, 8 H, 12 H, 16 H, 24 H, 36 H, 48 H, mice of each group were sacrificed. From the mice, peripheral blood mononuclear cells (PBMCs), splenocytes, and hepatocytes were separated.
Further, the spleen was removed and washed with PBS, and then placed on a dry ice and embedded in an O.C.T. compound (Sakura). After cryosectioning at 20 μm, tissue distributions of fluorescence-labeled-SOCS3 proteins in different organs was analyzed by fluorescence microscopy (Carl Zeiss, Gottingen, Germany).
Isolation of PBMC
After anesthesia with ether, ophthalmectomy was performed and the blood was collected therefrom using a 1 ml syringe. The collected blood was immediately put in an EDTA tube and mixed well. The blood was centrifuged at 4,000 rpm and 4° C. for 5 minutes, and plasma was discarded and only buffy coat was collected in a new microtube. 0.5 ml of RBC lysis buffer (Sigma) was added thereto, followed by vortexing. The microtube was left at room temperature for 5 minutes, and then centrifuged at 4,000 rpm and 4° C. for 5 minutes. 0.3 ml of PBS was added to a pellet, followed by pipetting and flow cytometry (FlowJo cytometric analysis software, Guava, Millipore, Darmstadt, Germany).
Isolation of Splenocytes and Hepatocytes
Mice were laparotomized and the spleen or liver were removed. The spleen or liver thus removed was separated into single cells using a Cell Strainer (SPL, Korea). These cells were collected in a microtube, followed by centrifugation at 4,000 rpm and 4° C. for 5 minutes. 0.5 ml of RBC lysis buffer was added thereto, followed by vortexing. The microtube was left at room temperature for 5 minutes, and then centrifuged at 4,000 rpm and 4° C. for 5 minutes. 0.5 ml of PBS was added to a pellet, followed by pipetting and flow cytometry (FlowJo cytometric analysis software, Guava, Millipore, Darmstadt, Germany).
As shown in
To investigate BA of the iCP-SOCS3 (HM165S3B) recombinant proteins, ICR mice (Doo-Yeol Biotech Co. Ltd., Seoul, Korea) were intravenous (IV) injected with 600 μg/head of 10 μM FITC (Fluorescein isothiocyanate, SIGMA, USA)-labeled SOCS3 proteins (HS3B, HM165S3B) and after 2 H, 8 H, 12 H, 24 H, mice of each group were sacrificed. From the mice, pancreas was removed and washed with PBS, and then placed on a dry ice and embedded in an O.C.T. compound (Sakura). After cryosectioning at 20 μm, tissue distributions of fluorescence-labeled-SOCS3 proteins in pancreas tissue was analyzed by fluorescence microscopy (Carl Zeiss, Gottingen, Germany) (
As shown in
Tumor-targeting of the anticancer agent iCP-SOCS3 (HM165S3B) recombinant proteins was investigated in an orthotopic xenograft model. The protocol was adapted from World J Gastroenterol. 2014 Jul. 28; 20(28): 9476-9485. To generate an orthotopic xenograft mouse model with PANC-1 cell, PANC-1-Luc cells (1×106 cells/mouse) cultured in RPMI 1640 (Hyclone, Logan, Utah, USA) containing 10% FBS were mixed with Matrigel at a 1:1 ratio and 200 μl of the mixture were injected into pancreas tail of female Balb/cnu/nu mice (5-week-old, Doo-Yeol Biotech Co. Ltd. Korea). After 7 weeks, the mice were IP injected with 100 μl of luciferin (Sigma-Aldrich, St. Louis, Mo., USA) and imaged by Xenogen IVIS-200 imaging system 15 minute later. As shown in
The iCP-SOCS3 recombinant proteins were labeled and IV injected to the mice with 40 mg/kg according to a manual of Alexa680 kit (Thermo Fisher Scientific, San Jose, Calif., USA). As shown in
To develop the iCP-SOCS3 recombinant protein as a therapeutic agent for lung cancer, its permeability to lung cancer cell lines and lung tissues was investigated.
A549 cells (ATCC, Manassas, Va., USA) were seeded in a 12 well plate, grown to 90% confluence. Cells were treated with 10 μM FITC-labeled iCP-SOCS3 recombinant proteins and cultivated for 1 hr at 37° C.
After cultivation, the cells were treated with proteinase K (10 μg/mL, SIGMA, USA) and washed three times with ice-cold PBS (Phosphate-buffered saline, Hyclone, USA) to remove surface-bound proteins, and internalized proteins were measured by flow cytometry (FlowJo cytometric analysis software, Guava, Millipore, Darmstadt, Germany). Untreated cells (gray) and equimolar concentration of unconjugated FITC (FITC only, green)-treated cells were served as control (
The lung tissue permeability was analyzed by the method described in Example 7-2.
As shown in
In addition, iCP-SOCS3 recombinant proteins (FITC-HM165S3SB) enhanced the systemic delivery to lung after intraperitoneal injection (
To develop the iCP-SOCS3 recombinant protein as a mechanism-specific therapeutic agent for lung cancer, SOCS3 levels endogenously expressed and activation of JAK/STAT-signaling pathway were investigated in different lung cancer cell lines, normal cells, and normal hepatic cells.
SOCS3 expression is suppressed due to methylation in cancer cells, and therefore, inflammation or cancer development is increased. Further, to investigate the effect of cell permeable SOCS3, a cancer cell line where endogenous SOCS3 expression is suppressed should be selected or applied to a model, and therefore, the present experiments were performed.
Genomic DNA was extracted from cancer cell line using an Exgene™ Tissue SV mini kit (Geneall®, Korea). DNA was quantified, and experiments were performed using 500 ng of gDNA and an EZ DNA Methylation-Gold™ kit (ZYMO Research, Orange, Calif., USA) according to the manufacturer's instructions. DNA was used to perform PCR, and methylation and unmethylation of endogenous SOCS3 were qualitatively analyzed by electrophoresis. In this regard, the primers used are as follows.
Unmethyl-F was 5′-tag tgt gta agt tgt agg aga gtg g-3′ (SEQ ID NO: 816), Unmethyl-R was 5′-cta aac ata aaa aaa taa cac taa tcc aaa-3′ (SEQ ID NO: 817), Methyl-F was 5′-gta gtg cgt aag ttg tag gag agc-3′ (SEQ ID NO: 818), and Methyl-R was 5′-gta aaa aaa taa cgc taa tcc gaa-3′ (SEQ ID NO: 819). PCR was performed for 30 cycles consisting of pre-denaturation at 95° C. for 5 minutes, denaturation at 95° C. for 30 seconds, annealing at 60° C. for 45 seconds, and extension at 72° C. for 1 minute, and then final extension at 72° C. for 8 minutes.
As shown in
SOCS3 mRNA expression levels in cancer cells were analyzed by RT-PCR. mRNAs were isolated from normal cell lines and cancer cell lines according to a method provided in a manufacturer's sheet of Hybrid-R (Geneall, Korea), and PCR was performed using SOCS3 primer F 5′-cct act gaa ccc tcc tcc ga-3′ (SEQ ID NO: 820) and SOCS3 primer R 5′-gca get ggg tga ctt tct ca-3′ (SEQ ID NO: 821) for 30 cycles consisting of denaturing (95° C.), annealing (60° C.), and extending (72° C.) for 45 seconds each.
It was confirmed that high expression levels of SOCS3 were observed in the normal HaCaT, HEK293 whereas low expression levels of SOCS3 were observed in the lung cancer cell lines (
JAK/STAT3 activation in cancer cells was analyzed by Western blot analysis. The normal HaCaT and HEK293 cells, and lung cancer cell lines, A549, NCI-H358, and NCI-H460 were washed with PBS, and then the cells were lysed in RIPA lysis buffer (Biosesang, Seongnam, Korea) containing proteinase inhibitor cocktail (Roche, Indianapolis, Ind., USA), incubated for 15 min at 4° C., and centrifuged at 13,000 rpm for 10 min at 4° C. to isolate proteins, followed by western blotting in the same manner as in Example 8-1.
As shown in
In order to develop the iCP-SOCS3 recombinant protein as a therapeutic agent for lung cancer, efficacy of iCP-SOCS3 on proliferation of lung cancer cell lines was investigated.
Cells originated from human lung cell (A549), HEK293 and mouse fibroblast (NIH3T3) were purchased from ATCC (Manassas, Va., USA) and maintained as recommended by the supplier. These cells (3×103/well) were seeded in 96 well plates. The next day, cells were treated with DMEM (vehicle) or recombinant SOCS3 proteins for 96 hrs in the presence of serum (2%). Proteins were replaced daily. Cell growth and survival were evaluated with the CellTiter-Glo Cell Viability Assay (Promega, Madison, Wis.). Measurements using a Luminometer (Turner Designs, Sunnyvale, Calif.) were conducted following the manufacturer's protocol.
As shown in
In order to develop the iCP-SOCS3 recombinant protein as a therapeutic agent for lung cancer, efficacy of iCP-SOCS3 on migration and metastasis of lung cancer cell lines was investigated.
A549 cells were seeded into 12-well plates, grown to 90% confluence, and incubated with 10 μM HS3B (Non-CP-SOCS3), HM165S3B (iCP-SOCS3) in serum-free medium for 2 hrs prior to changing the growth medium. The cells were washed twice with PBS, and the monolayer at the center of the well was “wounded” by scraping with a pipette tip. Cells were cultured for an additional 24-72 hrs and cell migration was observed by phase contrast microscopy. The migration is quantified by counting the number of cells that migrated from the wound edge into the clear area.
As shown in
The lower surface of Transwell inserts (Costar) was coated with 0.1% gelatin, and the membranes were allowed to dry for 1 hr at room temperature. The Transwell inserts were assembled into a 24-well plate, and the lower chamber was filled with growth media containing 10% FBS and FGF2 (40 ng/ml). Cells were added to each upper chamber at a density of 5×105, and the plate was incubated at 37° C. in a 5% CO2 incubator for 24 hrs. Migrated cells were stained with 0.6% hematoxylin and 0.5% eosin and counted.
As shown in
Invasion Assay
The lower surface of Transwell inserts (Costar) was coated with 0.1% gelatin, the upper surface of Transwell inserts was coated with matrigel (40 μg per well; BD Pharmingen, San Diego, Calif., USA), and the membranes were allowed to dry for 1 hr at room temperature. The Transwell inserts were assembled into a 24-well plate, and the lower chamber was filled with growth media containing 10% FBS and FGF2 (40 ng/ml). Cells (5×105) were added to each upper chamber, and the plate was incubated at 37° C. in a 5% CO2 incubator for 24 hrs. Migrated cells were stained with 0.6% hematoxylin and 0.5% eosin and counted.
As shown in
To further determine the effect of iCP-SOCS3 on the tumorigenicity of lung cancer cells, we subsequently investigated whether iCP-SOCS3 regulates apoptosis in A549 cells.
Annexin V/7-Aminoactinomycin D (7-AAD) staining was performed using flow cytometry according to the manufacturer's guidelines (BD Pharmingen, San Diego, Calif., USA). Briefly, 1×106 cells were washed three times with ice-cold PBS. The cells were then resuspended in 100 μl of binding buffer and incubated with 1 μl of 7-AAD and 1 μl of Annexin V-7-AAD for 30 min in the dark at 4° C. Flow cytometric analysis was immediately performed using a guava easyCyte™ 8 Instrument (Merck Millipore, Darmstadt, Germany).
As shown in
To further determine the effect of iCP-SOCS3 on the tumorigenicity of lung cancer cells, we subsequently investigated whether iCP-SOCS3 regulates apoptosis in lung cancer cell (A549).
Apoptotic cells were analyzed using terminal dUTP nick-end labeling (TUNEL) assay with In Situ Cell Death Detection kit TMR red (Roche, 4056 Basel, Switzerland). Cells were treated for 24 hr with 10 μM HS3B or HM165S3B proteins with 2% fetal bovine serum and apoptotic cells were visualized by TUNEL staining. Treated cells were washed with cold PBS two times, fixed in 4% paraformaldehyde (PFA, Junsei, Tokyo, Japan) for 1 hr at room temperature, and incubated in 0.1% Triton X-100 for 2 min on the ice. Cells were washed with cold PBS twice, and treated TUNEL reaction mixture for 1 hr at 37° C. in dark, washed cold PBS three times and observed by fluorescence microscopy (Nikon, Tokyo, Japan).
HM165S3B protein (iCP-SOCS3) was considerably efficient inducer of apoptosis in A549 cells (
To further determine the effect of iCP-SOCS3 on the tumorigenicity of lung cancer cells, we subsequently investigated whether iCP-SOCS3 regulates cell cycle progression in lung cancer cell (A549 cell).
A549 cells were treated with 10 uM protein (Non-CP-SOCS3 (HS3B) and iCP-SOSC3 (HM165S3B)) for 8 hrs. After the treatment, cells were washed twice with cold PBS and re-suspended in 1 ml cold PBS, fixed in cold 70% ethanol, washed with cold PBS twice and re-suspended in PI master mix (PI 10 ug/ml (sigma), 50 ug/ml RNase A (invitrogen) in staining buffer) at a final cell density of 2×105 cell/ml. The cell mixtures were incubated 30 min in the dark at 4° C. Flow cytometric analysis was immediately performed using a guava easyCyte™ 8 Instrument (Merck Millipore, Darmstadt, Germany).
To further determine the effect of iCP-SOCS3 on the tumorigenicity of lung cancer cells, we subsequently investigated whether iCP-SOCS3 regulates cell cycle progression in lung cancer cells. HM165S3B protein (iCP-SOCS3) efficiently inhibits cell cycle progression in A549 cells (
Anti-tumor activity of iCP-SOCS3 against human cancer xenografts was assessed. Female Balb/cnu/nu mice (5-week-old, Doo-Yeol Biotech Co. Ltd. Korea) were subcutaneously implanted with A549.1-7 tumor block (1 mm3) into the left back side of the mouse.
Tumor-bearing mice were intravenously administered with 600 μg/head of iCP-SOCS3 (HM165S3B) or the control proteins (HS3B) for 21 days and observed for 2 weeks following the termination of the treatment. After protein treatment, mice were killed, and six organs (brain, heart, lung, liver, kidney, and spleen) from each were collected and kept in a suitable fixation solution until the next step. Tumor size was monitored by measuring the longest (length) and shortest dimensions (width) once a day with a dial caliper, and tumor volume was calculated as width2×length×0.5.
As shown in
In the following experiments, RT-PCR and IHC were performed by the following method.
RT-PCR
Tumor tissues were finely minced using a homogenizer according to the manufacturer's protocol of Hybrid-R (geneall, Korea), and then mRNA was isolated therefrom. 1 ug of mRNA thus separated was used to synthesize cDNA using an Accupower RT Premix (Bioneer, Korea). PCR was performed using 2 ul of cDNA and the primers of Table 45. PCR was performed using an Accupower PCR Premix (Bioneer, Korea) for 30 cycles consisting of denaturing (95° C.), annealing (60° C.), and extending (72° C.) for 45 seconds each.
As shown in
Immunohistochemistry (IHC)
Tissue samples were fixed in 4% Paraformaldehyde (Duksan, South Korea) for 3 days, dehydrated, cleared with xylene and embedded in Paraplast. Sections (6 μm thick) of tumor were placed onto poly-L-lysine coated slides. To block endogenous peroxidase activity, sections were incubated for 15 min with 3% H2O2 in methanol. After washing three times with PBS, slides were incubated for 30 min with blocking solution (5% fetal bovine serum in PBS). Mouse anti-Bax antibody (sc-7480, Santa Cruz Biotechnology, SantaCruz, Calif., USA) and rabbit anti-VEGF (ab46154, Abcam, Cambridge, UK) were diluted 1:1000 (to protein concentration 0.1 μg/ml) in blocking solution, applied to sections, and incubated at 4° C. for 24 hrs. After washing three times with PBS, sections were incubated with biotinylated mouse and rabbit IgG (Vector Laboratories, Burlingame, Calif., USA) at a 1:1000 dilution for 1 hr at room temperature, then incubated with avidin-biotinylated peroxidase complex using a Vectorstain ABC Kit (Vector Laboratories, Burlingame, Calif., USA) for 30 min at room temperature. After the slides are reacted with oxidized 3, 3-diaminobenzidine as a chromogen, they were counterstained with Harris hematoxylin (Sigma-Aldrich, USA). Permanently mounted slides were observed and photographed using a microscope equipped with a digital imaging system (ECLIPSE Ti, Nikon, Japan).
In iCP-SOCS3-treated tumor tissues, expressions of a cell cycle regulator (p21, p27, Cyclin E, Cyclin A1, CDK4) and an apoptosis inducer (Survivin, Bax) were increased. Further, expression of an angiogenesis inducer (HIF1α, VEGF, FAK) was also remarkably decreased (
Statistical Analysis
Statistical analysis and graphic presentation have been performed using GraphPad Prism 5.01 software (GraphPad, La Jolla, Calif., USA). All experimental data are presented as means±SEM. Statistical significance was analyzed by the Student's t-test or ANOVA method. Experimental differences between groups were assessed using paired Student's t-tests. For animal experiments, ANOVA was used for comparing between and within groups to determine the significance. Differences with p<0.05 are considered to be statistically significant.
Those skilled in the art to which the present invention pertains will appreciate that the present invention may be implemented in different forms without departing from the essential characteristics thereof. Therefore, it should be understood that the disclosed embodiments are not limitative, but illustrative in all aspects. The scope of the present invention is made to the appended claims rather than to the foregoing description, and all variations which come within the range of equivalency of the claims are therefore intended to be embraced therein.
| Number | Date | Country | |
|---|---|---|---|
| 62042493 | Aug 2014 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 14838280 | Aug 2015 | US |
| Child | 15408230 | US |
