Therapy response for many complex diseases may continue to elude researchers and practitioners. A single stratification factor or biomarker may be insufficient to determine whether a therapy is effective in treating a particular patient. Instead, many diseases, such as autoimmune diseases, cancers, and the like, affect a multitude of biological sub-systems. (See e.g., Frohlich et al., BMC Med, 16, 150:1122-1127 (2018), which is incorporated herein by reference for all purposes). Effective treatment of these diseases may require a therapy capable of targeting or modulating multiple proteins and associated biological processes. A reactive approach (e.g., a trial-and-error approach) to identifying treatment for patients may be costly and introduce risk for adverse side effects, potential disease progression, and delay of proper treatment. (See e.g., Mathur & Sutton, Biomed. Rep., 7:3-5 (2017), which is incorporated herein by reference for all purposes). Moreover, confirmation of response may be limited to analysis of clinical characteristics, which do not always indicate true response or regression of a disease.
To date, many approaches to determining suitability of a therapy for a particular subject may rely on a reactive approach of attempting multiple therapies, attempting to gauge patient response by assessing clinical characteristics. These approaches may delay necessary treatment and may mischaracterize the actual responsiveness of a therapy for a patient by only examining clinical characteristics of response. Therefore, there is a need for methods and systems of providing personalized treatments for patients that avoid such pitfalls.
The present disclosure provides methods and systems that encompass an insight that treating a patient on a molecular level, e.g., providing a treatment that converts a subset of a gene expression profile from a diseased subject to resemble the gene expression profile a healthy subject, proactively, may be a better metric for assessing drug molecular response and identifying effective therapy than by a reactive approach, or seeking out a singly one-size-fits-all biomarker. Provided technologies, among other things, permit providers to identify particular methods and modes of treatment that may work for that particular patient and allow providers to monitor disease progression and treatment response without relying on subjective measures, such as clinical characteristics or patient self-assessment. In some embodiments, certain gene expression patterns for diseased patients are indicative of a response to therapy, and reversal of gene expression of this gene expression pattern in a diseased patient indicates improvement of the health of the diseased subject (“a disease gene expression signature”). Such an approach is distinct from other methods, which examines gene expression differences between patients suffering from the disease, in order to identify whether a patient has a biomarker indicative for response to therapy, as compared to other patients who do not.
In some embodiments, a disease gene expression signature is identified using a machine learning algorithm that identifies genes that are differentially expressed between diseased subjects, subsets of diseased subjects, and healthy subjects in a significant manner. Moreover, the present disclosure provides methods and systems that encompass an insight that certain genes within a gene expression profile of a disease subject, when compared to the gene expression profile of a healthy subject, lead to potential targets for therapy that are distinct from the differentially expressed genes in the diseased subject as compared to the healthy subject. That is, while other methods focus on differentially expressed genes in a diseased subject vs. a healthy subject, the present disclosure instead identifies targets for therapy that have significant connection (and thus impact) to these differentially expressed genes but may not be differentially expressed themselves as between diseased and healthy subjects. In some embodiments, a potential target for therapy has a significant connection to the differentially expressed genes in the diseased subject, such that modulating the target may reverse gene expression of the disease gene expression signature after treatment, thereby indicating that the subject's disease is responding to the particular therapy.
Further, the present disclosure provides methods and systems that encompass an insight that multiple targets for therapy can potentially have a significant connection to the differentially expressed genes in the diseased subject. Accordingly, it may be beneficial to provide a method for identifying which target from among the several targets yields the highest likelihood of success to reverse gene expression of the disease gene expression signature after treatment. In some embodiments, likelihood of success of target modulation to impact a disease gene expression response signature is determined using machine learning algorithms to predict response when a candidate target is modulated. In some embodiments, such a prediction is performed by assessing network proximity (which can include, for example, significance of connection) between a candidate target and each of the genes in a disease expression signature. In some embodiments, artificial intelligence software modules predict targets of highest significance to the disease gene expression response signature, thereby providing a target of interest for therapy of a diseased subject.
In an aspect, the present disclosure provides a method of determining or validating a target for therapy for treating a subject suffering from a disease, disorder, or condition, the method comprising: receiving a set of response genes corresponding to a disease gene expression signature, wherein the disease gene expression signature comprises one or more genes that, when expression is reversed in whole or in part, resembles gene expression of a non-diseased subject; receiving a plurality of interactions between one or more potential therapies and a plurality of gene expressions; generating, for each response gene of the set of response genes, one or more potential therapies that alter gene expression of the response gene, based at least in part on the plurality of interactions; scoring each of the one or more potential therapies based at least in part on significance of alteration of the set of response genes, to thereby provide one or more candidate therapies; determining one or more potential targets directly modulated by the one or more candidate therapies; selecting one or more secondary targets sharing significant similarity to the one or more potential targets; compiling a set of targets comprising the one or more potential targets and the one or more secondary targets; and identifying a target from the set of targets having a significant downstream impact similarity to the set of response genes to thereby provide the target for therapy.
In some embodiments, the method further comprises mapping each of the one or more potential targets onto a biological network, and selecting one or more secondary targets sharing significant topological similarity to the one or more potential targets on the biological network. In some embodiments, the biological network comprises a human interactome. In some embodiments, the biological network is a human protein-protein interactome. In some embodiments, significant topological similarity of the one or more secondary targets is determined via identification of targets that are proximal to the one or more potential targets on the biological network.
In some embodiments, the target for therapy is directly modulated by the one or more candidate therapies. In some embodiments, the target for therapy is not associated with an approved therapy for the disease, disorder, or condition. In some embodiments, the target for therapy is associated with a second disease different from the disease, disorder, or condition. In some embodiments, the therapy comprises a member selected from Table 1. In some embodiments, the therapy comprises gene knockout or gene overexpression. In some embodiments, the therapy comprises an anti-TNF therapy. In some embodiments, the anti-TNF therapy comprises infliximab, etanercept, adalimumab, certolizumab pegol, golimumab, or a biosimilar thereof. In some embodiments, the one or more potential targets comprises JAK1, JAK2, JAK3, IL23A, ITGA4, ITGB7, IL2RA, IL12A, IL12B, TNF, IL12RB1, IL23R, IL12RB2, or MADCAM1. In some embodiments, the significance in alteration comprises a significant change in gene expression of the set of response genes.
In some embodiments, the disease, disorder, or condition comprises an autoimmune disease, disorder, or condition. In some embodiments, the disease, disorder, or condition comprises ulcerative colitis, Crohn's disease, rheumatoid arthritis, juvenile arthritis, psoriatic arthritis, plaque psoriasis, ankylosing spondylitis, Guillain-Barre syndrome, Sjogren's syndrome, scleroderma, vitiligo, bipolar disorder, Graves' disease, schizophrenia, Alzheimer's disease, multiple sclerosis, Parkinson's disease, or a combination thereof. In some embodiments, the disease, disorder, or condition comprises ulcerative colitis. In some embodiments, the disease, disorder, or condition comprises rheumatoid arthritis. In some embodiments, the disease, disorder, or condition comprises Alzheimer's disease. In some embodiments, the disease, disorder, or condition comprises multiple sclerosis.
In another aspect, the present disclosure provides a method of treating a subject suffering from a disease, disorder, or condition, wherein the subject exhibits a disease gene expression signature associated with the disease, disorder, or condition, the method comprising administering to the subject a therapy that has been determined to revert the disease gene expression signature toward a non-diseased gene expression signature, wherein the therapy has been determined at least in part by: receiving a set of response genes corresponding to the disease gene expression signature, wherein the disease gene expression signature comprises one or more genes that, when expression is reversed in whole or in part, resembles gene expression of a non-diseased subject; receiving a plurality of interactions between one or more potential therapies and a plurality of gene expressions; generating, for each response gene of the set of response genes, one or more potential therapies that alter gene expression of the response gene, based at least in part on the plurality of interactions; scoring each of the one or more potential therapies based at least in part on significance of alteration of the set of response genes, to thereby provide one or more candidate therapies; determining one or more potential targets directly modulated by the one or more candidate therapies; selecting one or more secondary targets sharing significant similarity to the one or more potential targets; compiling a set of targets comprising the one or more potential targets and the one or more secondary targets; selecting a target from the list of targets for the therapy having a significant downstream impact similarity to the set of response genes; and determining that the therapy directly modulates the target.
In some embodiments, the therapy has been determined at least in part by further mapping each of the one or more potential targets onto a biological network, and selecting one or more secondary targets sharing significant topological similarity to the one or more potential targets on the biological network. In some embodiments, the biological network comprises a human interactome. In some embodiments, the biological network is a human protein-protein interactome. In some embodiments, significant topological similarity of the one or more secondary targets is determined via identification of targets that are proximal to the one or more potential targets.
In some embodiments, the disease gene expression signature is determined at least in part by: analyzing gene expression data from a cohort of subjects suffering from the disease, disorder, or condition; stratifying the cohort of subjects into two or more groups of prior subjects based at least in part on the gene expression data; and selecting one or more genes having significant differences in gene expression between the two or more groups of prior subjects and a group of non-diseased subjects (“disease candidate genes”), to thereby provide the disease gene expression signature. In some embodiments, stratifying the cohort of subjects into two or more groups of prior subjects is based on whether the prior subjects do or do not respond to a particular therapy.
In some embodiments, the target for the therapy is directly modulated by the one or more candidate therapies. In some embodiments, target for therapy is not associated with an approved therapy for the disease, disorder, or condition. In some embodiments, the therapy comprises an anti-TNF therapy. In some embodiments, the anti-TNF therapy comprises infliximab, etanercept, adalimumab, certolizumab pegol, golimumab, or a biosimilar thereof. In some embodiments, the therapy comprises gene knockout or gene overexpression. In some embodiments, the therapy comprises a member selected from Table 1. In some embodiments, the one or more potential targets comprises JAK1, JAK2, JAK3, IL23A, ITGA4, ITGB7, IL2RA, IL12A, IL12B, TNF, IL12RB1, IL23R, IL12RB2, or MADCAM1. In some embodiments, the significance in alteration comprises a significant change in gene expression of the set of response genes.
In some embodiments, the disease, disorder, or condition comprises an autoimmune disease, disorder, or condition. In some embodiments, the disease, disorder, or condition comprises ulcerative colitis, Crohn's disease, rheumatoid arthritis, juvenile arthritis, psoriatic arthritis, plaque psoriasis, ankylosing spondylitis, Guillain-Barre syndrome, Sjogren's syndrome, scleroderma, vitiligo, bipolar disorder, Graves' disease, schizophrenia, Alzheimer's disease, multiple sclerosis, Parkinson's disease, or a combination thereof. In some embodiments, the disease, disorder, or condition comprises ulcerative colitis. In some embodiments, the disease, disorder, or condition comprises rheumatoid arthritis. In some embodiments, the disease, disorder, or condition comprises Alzheimer's disease. In some embodiments, the disease, disorder, or condition comprises multiple sclerosis.
In some embodiments, scoring of each of the one or more potential therapies comprises: determining a difference in expression level of the set of response genes after treatment with the one or more potential therapies relative to the set of response genes before treatment with the one or more potential therapies; and calculating a p-value for each of the one or more potential therapies.
In some embodiments, the potential targets are identified via a machine-learning algorithm. In some embodiments, the machine-learning algorithm comprises a random walk.
In another aspect, the present disclosure provides a method for determining a personalized therapy for a subject, the method comprising: receiving or generating a disease gene expression signature comprising a set of response genes; receiving or generating one or more potential therapies that alter expression of the set of response genes; ranking each of the one or more potential therapies based at least in part on significance of alteration of the set of response genes, to thereby provide one or more candidate therapies; determining one or more potential targets directly modulated by the one or more candidate therapies; ranking one or more secondary targets based at least in part on significance of similarity to the one or more potential targets; compiling a set of targets comprising the one or more potential targets and the one or more secondary targets; selecting a target from the set of targets for the personalized therapy having a significant downstream impact similarity to the set of response genes; and determining that the personalized therapy directly modulates the target.
In some embodiments, the method further comprises mapping each of the one or more potential targets onto a biological network, and ranking one or more secondary targets based at least in part on significance of topological similarity to the one or more potential targets on the biological network. In some embodiments, the biological network comprises a human interactome.
In some embodiments, the disease gene expression signature is determined at least in part by: analyzing gene expression data from a cohort of subjects suffering from the disease, disorder, or condition; stratifying the cohort of subjects into two or more groups of prior subjects based at least in part on the gene expression data; and selecting one or more genes having significant differences in gene expression between the two or more groups of prior subjects and a group of non-diseased subjects (“disease candidate genes”), to thereby provide the disease gene expression signature.
In another aspect, the present disclosure provides a system comprising: a processor of a computing device; and a memory having instructions stored thereon, wherein the instructions, when executed by the processor cause the processor to perform any of the methods provided herein.
In another aspect, the present disclosure provides a method of determining or validating a target for therapy for treating a subject suffering from a disease, disorder, or condition, the method comprising: receiving a set of response genes corresponding to a disease gene expression signature, wherein the disease gene expression signature is or comprises one or more genes that, when expression is reversed in whole or in part, resembles gene expression of a healthy subject; receiving a plurality of interactions between one or more potential therapies and a plurality of gene expressions; generating for each gene of the set of response genes, one or more potential therapies that alter gene expression of the set of response genes; scoring each of the one or more potential therapies based on significance of alteration (e.g., the change in gene expression) of the set of response genes, to thereby provide one or more candidate therapies; determining one or more potential targets directly modulated by the one or more candidate therapies; mapping each of the one or more potential targets onto a biological network; selecting one or more secondary targets sharing significant topological similarity to the one or more potential targets on the biological network; compiling a list of targets comprising the one or more potential targets and the one or more secondary targets; identifying a target having a significant downstream impact similarity to the set of response genes from the list of targets to thereby provide the target for therapy.
In some embodiments, the target for therapy is directly modulated by the one or more candidate therapies.
In some embodiments, significant topological similarity of the one or more secondary targets is determined via identification of targets that are proximal to the one or more potential targets.
In some embodiments, the target for therapy is not associated (e.g., is not approved for use) with a therapy.
In some embodiments, the target for therapy is associated (e.g., is approved for use) with a disease distinct from the disease afflicting the subject (e.g., is a “novel target”).
In some embodiments, the therapy comprises a member selected from Table 1.
In some embodiments, the therapy comprises gene knockout or gene overexpression.
In some embodiments, the therapy comprises an anti-TNF therapy.
In some embodiments, the one or more potential targets is selected from JAK1, JAK2, JAK3, IL23A, ITGA4, ITGB7, IL2RA, IL12A, IL12B, TNF, IL12RB1, IL23R, IL12RB2, and MADCAM1.
In another aspect, the present disclosure provides a method of treating a subject that exhibits a disease gene expression signature, the method comprising administering a therapy determined to revert the disease gene expression signature toward a healthy gene expression signature, wherein the therapy has been determined by: selecting a set of response genes from the disease gene expression signature; identifying one or more potential therapies that alter gene expression of the set of response genes; scoring each of the one or more potential therapies based on significance of alteration of the set of response genes to provide one or more candidate therapies; determining one or more potential targets directly modulated by the one or more candidate therapies; mapping each of the one or more potential targets onto a biological network; selecting one or more secondary targets sharing significant topological similarity to the one or more potential targets on the biological network; compiling a list of targets comprising the one or more potential targets and the one or more secondary targets; selecting a target for treatment from the list of targets by identifying a target having a significant downstream impact to the set of response genes; and identifying the therapy that directly modulates the target for treatment.
In some embodiments, the disease gene expression signature is determined by: analyzing gene expression data from a cohort of subjects suffering from the same disease, disorder, or condition as the subject, stratifying the cohort of subjects into two or more groups of prior subjects based on the gene expression data; and selecting one or more genes having significant differences in gene expression between the two or more groups of prior subjects and a group of healthy subjects (“disease candidate genes”), to thereby provide the disease gene expression signature.
In some embodiments, the target for treatment is directly modulated by the one or more candidate therapies.
In some embodiments, significant topological similarity of the one or more secondary targets is determined via identification of targets that are proximal to the one or more potential targets
In some embodiments, target for therapy is not associated with a therapy.
In some embodiments, the therapy comprises an anti-TNF therapy.
In some embodiments, the anti-TNF therapy is selected from infliximab, etanercept, adalimumab, certolizumab pegol, golimumab, and biosimilars thereof.
In some embodiments, the therapy comprises a member selected from Table 1.
In some embodiments, the one or more potential targets are selected from JAK1, JAK2, JAK3, IL23A, ITGA4, ITGB7, IL2RA, IL12A, IL12B, TNF, IL12RB1, IL23R, IL12RB2, and MADCAM1
In some embodiments, the disease, disorder, or condition comprises ulcerative colitis, Crohn's disease, rheumatoid arthritis, juvenile arthritis, psoriatic arthritis, plaque psoriasis, ankylosing spondylitis, Guillain-Barre syndrome, Sjogren's syndrome, scleroderma, vitiligo, bipolar disorder, Graves' disease, schizophrenia, Alzheimer's disease, multiple sclerosis, Parkinson's disease, or a combination thereof.
In some embodiments, scoring of each of the one or more potential therapies comprises: determining a difference in expression level of the set of response genes after treatment with the one or more potential therapies relative to the set of response genes before treatment with the one or more potential therapies; and calculating a p-value for each of the one or more potential therapies.
In some embodiments, the potential targets are identified by a machine-learning algorithm.
In some embodiments, the machine-learning algorithm comprises a random walk.
In some embodiments, stratifying the cohort of subjects into two or more groups of prior subjects is based at least in part on whether the prior subjects do or do not respond to a particular therapy.
In another aspect, the present disclosure provides a method for engineering a personalized therapy for a subject, the method comprising: receiving or generating a disease gene expression signature comprising a set of response genes; receiving or generating a set of one or more potential therapies that alter expression of the one or more response genes; ranking each of the set of the one or more potential therapies according to significance of alteration of the one or more response genes, to provide a set of one or more candidate therapies; determining one or more potential targets directly modulated by the set of one or more candidate therapies, optionally by mapping the one or more potential targets onto a biological network; and ranking significance of topological similarity between each of the one or more potential targets and the set of response genes; mapping each of the one or more potential targets onto a biological network; identifying one or more secondary targets sharing significant downstream impact to the one or more potential targets; compiling a list of targets comprising the one or more potential targets and the one or more secondary targets; selecting a target for treatment from the list of targets; and selecting the personalized therapy that modulates the target for treatment.
In some embodiments, the disease gene expression signature is determined by: receiving or generating gene expression data from a cohort of subjects suffering from the same disease, disorder, or condition as the subject; stratifying the cohort of subjects into two or more groups of prior subjects based on the gene expression data; and selecting one or more genes having significant differences in gene expression between the two or more groups of prior subjects and a group of healthy subjects (“disease candidate genes”), to thereby provide the disease gene expression signature.
In another aspect, the present disclosure provides a system for determining or validating a target for therapy for treating a subject suffering from a disease, the system comprising: a processor of a computing device; and a memory having instructions stored thereon, wherein the instructions, when executed by the processor cause the processor to perform one or more operations of any method described herein.
Another aspect of the present disclosure provides a non-transitory computer readable medium comprising machine executable code that, upon execution by one or more computer processors, implements any of the methods above or elsewhere herein.
Another aspect of the present disclosure provides a system comprising one or more computer processors and computer memory coupled thereto. The computer memory comprises machine executable code that, upon execution by the one or more computer processors, implements any of the methods above or elsewhere herein.
Additional aspects and advantages of the present disclosure will become readily apparent to those skilled in this art from the following detailed description, wherein only illustrative embodiments of the present disclosure are shown and described. As will be realized, the present disclosure is capable of other and different embodiments, and its several details are capable of modifications in various obvious respects, all without departing from the disclosure. Accordingly, the drawings and description are to be regarded as illustrative in nature, and not as restrictive.
All publications, patents, and patent applications mentioned in this specification are herein incorporated by reference to the same extent as if each individual publication, patent, or patent application was specifically and individually indicated to be incorporated by reference. To the extent publications and patents or patent applications incorporated by reference contradict the disclosure contained in the specification, the specification is intended to supersede or take precedence over any such contradictory material.
While various embodiments of the invention have been shown and described herein, it will be obvious to those skilled in the art that such embodiments are provided by way of example only. Numerous variations, changes, and substitutions may occur to those skilled in the art without departing from the invention. It should be understood that various alternatives to the embodiments of the invention described herein may be employed.
Provided herein are systems and methods that are useful, for example, for the treatment and prevention of disease. In some embodiments, the present disclosure provides systems and methods for identifying a set of genes that, when differentially expressed as compared to a healthy subject, indicate response to therapy. In some embodiments, the present disclosure provides systems and methods for identifying targets for therapy that may or may not be differentially expressed as between healthy and diseased subjects.
Administration: As used herein, the term “administration” generally refers to the administration of a composition to a subject or system, for example to achieve delivery of an agent that is, or is included in or otherwise delivered by, the composition.
Agent: As used herein, the term “agent” generally refers to an entity (e.g., for example, a lipid, metal, nucleic acid, polypeptide, polysaccharide, small molecule, etc., or complex, combination, mixture or system [e.g., cell, tissue, organism] thereof), or phenomenon (e.g., heat, electric current or field, magnetic force or field, etc.).
Amino acid: As used herein, the term “amino acid” generally refers to any compound or substance that can be incorporated into a polypeptide chain, e.g., through formation of one or more peptide bonds. In some embodiments, an amino acid has the general structure H2N—C(H)(R)—COOH. In some embodiments, an amino acid is a naturally-occurring amino acid. In some embodiments, an amino acid is a non-natural amino acid; in some embodiments, an amino acid is a D-amino acid; in some embodiments, an amino acid is an L-amino acid. As used herein, the term “standard amino acid” refers to any of the twenty L-amino acids commonly found in naturally occurring peptides. “Nonstandard amino acid” refers to any amino acid, other than the standard amino acids, regardless of whether it is or can be found in a natural source. In some embodiments, an amino acid, including a carboxy- or amino-terminal amino acid in a polypeptide, can contain a structural modification as compared to the general structure above. For example, in some embodiments, an amino acid may be modified by methylation, amidation, acetylation, pegylation, glycosylation, phosphorylation, or substitution (e.g., of the amino group, the carboxylic acid group, one or more protons, or the hydroxyl group) as compared to the general structure. In some embodiments, such modification may, for example, alter the stability or the circulating half-life of a polypeptide containing the modified amino acid as compared to one containing an otherwise identical unmodified amino acid. In some embodiments, such modification does not significantly alter a relevant activity of a polypeptide containing the modified amino acid, as compared to one containing an otherwise identical unmodified amino acid. In some embodiments, the term “amino acid” may be used to refer to a free amino acid; in some embodiments it may be used to refer to an amino acid residue of a polypeptide, e.g., an amino acid residue within a polypeptide.
Analog: As used herein, the term “analog” generally refers to a substance that shares one or more particular structural features, elements, components, or moieties with a reference substance. In some embodiments, an “analog” shows significant structural similarity with the reference substance, for example sharing a core or consensus structure, but also differs in certain discrete ways. In some embodiments, an analog is a substance that can be generated from the reference substance, e.g., by chemical manipulation of the reference substance. In some embodiments, an analog is a substance that can be generated through performance of a synthetic process substantially similar to (e.g., sharing a plurality of operations with) one that generates the reference substance. In some embodiments, an analog is or can be generated through performance of a synthetic process different from that used to generate the reference substance.
Antagonist: As used herein, the term “antagonist” may generally refer to an agent, or condition whose presence, level, degree, type, or form is associated with a decreased level or activity of a target. An antagonist may include an agent of any chemical class including, for example, small molecules, polypeptides, nucleic acids, carbohydrates, lipids, metals, or any other entity that shows the relevant inhibitory activity. In some embodiments, an antagonist may be a “direct antagonist” in that it binds directly to its target; in some embodiments, an antagonist may be an “indirect antagonist” in that it exerts its influence by mechanisms other than binding directly to its target; e.g., by interacting with a regulator of the target, so that the level or activity of the target is altered). In some embodiments, an “antagonist” may be referred to as an “inhibitor”.
Antibody: As used herein, the term “antibody” generally refers to a polypeptide that includes canonical immunoglobulin sequence elements sufficient to confer specific binding to a particular target antigen. Intact antibodies as produced in nature are approximately 150 kD tetrameric agents comprised of two identical heavy chain polypeptides (about 50 kD each) and two identical light chain polypeptides (about 25 kD each) that associate with each other into what is commonly referred to as a “Y-shaped” structure. Each heavy chain is comprised of at least four domains (each about 110 amino acids long)—an amino-terminal variable (VH) domain (located at the tips of the Y structure), followed by three constant domains: CH1, CH2, and the carboxy-terminal CH3 (located at the base of the Y's stem). A short region, or “switch”, connects the heavy chain variable and constant regions. The “hinge” connects CH2 and CH3 domains to the rest of the antibody. Two disulfide bonds in this hinge region connect the two heavy chain polypeptides to one another in an intact antibody. Each light chain is comprised of two domains—an amino-terminal variable (VL) domain, followed by a carboxy-terminal constant (CL) domain, separated from one another by another “switch”. Intact antibody tetramers are comprised of two heavy chain-light chain dimers in which the heavy and light chains are linked to one another by a single disulfide bond; two other disulfide bonds connect the heavy chain hinge regions to one another, so that the dimers are connected to one another and the tetramer is formed. Naturally-produced antibodies are also glycosylated, such as on the CH2 domain. Each domain in a natural antibody has a structure characterized by an “immunoglobulin fold” formed from two beta sheets (e.g., 3-, 4-, or 5-stranded sheets) packed against each other in a compressed antiparallel beta barrel. Each variable domain contains three hypervariable loops (“complement determining regions”) (CDR1, CDR2, and CDR3) and four somewhat invariant “framework” regions (FR1, FR2, FR3, and FR4). When natural antibodies fold, the FR regions form the beta sheets that provide the structural framework for the domains, and the CDR loop regions from both the heavy and light chains are brought together in three-dimensional space so that they create a single hypervariable antigen binding site located at the tip of the Y structure. The Fc region of naturally-occurring antibodies binds to elements of the complement system, and also to receptors on effector cells, including for example effector cells that mediate cytotoxicity. Affinity or other binding attributes of Fc regions for Fc receptors can be modulated through glycosylation or other modification. In some embodiments, antibodies produced or utilized in accordance with the present disclosure include glycosylated Fc domains, including Fc domains with modified or engineered such glycosylation. For purposes of the present disclosure, in certain embodiments, any polypeptide or complex of polypeptides that includes sufficient immunoglobulin domain sequences as found in natural antibodies can be referred to or used as an “antibody”, whether such polypeptide is naturally produced (e.g., generated by an organism reacting to an antigen), or produced by recombinant engineering, chemical synthesis, or other artificial system or methodology. In some embodiments, an antibody is polyclonal; in some embodiments, an antibody is monoclonal. In some embodiments, an antibody has constant region sequences that are characteristic of mouse, rabbit, primate, or human antibodies. In some embodiments, antibody sequence elements are humanized, primatized, chimeric, etc. Moreover, the term “antibody” as used herein, can refer in appropriate embodiments (unless otherwise stated or clear from context) to any constructs or formats for utilizing antibody structural and functional features in alternative presentation. For example, embodiments, an antibody utilized in accordance with the present disclosure is in a format selected from, but not limited to, intact IgA, IgG, IgE or IgM antibodies; bi- or multi-specific antibodies (e.g., Zybodies®, etc.); antibody fragments such as Fab fragments, Fab′ fragments, F(ab′)2 fragments, Fd′ fragments, Fd fragments, and isolated CDRs or sets thereof; single chain Fvs; polypeptide-Fc fusions; single domain antibodies (e.g., shark single domain antibodies such as IgNAR or fragments thereof); cameloid antibodies; masked antibodies (e.g., Probodies®); Small Modular ImmunoPharmaceuticals (“SMIPs™”); single chain or Tandem diabodies (TandAb®); VHHs; Anticalins®; Nanobodies® minibodies; BiTE®s; ankyrin repeat proteins or DARPINs®; Avimers®; DARTs; TCR-like antibodies; Adnectins®; Affilins®; Trans-bodies®; Affibodies®; TrimerX®; MicroProteins; Fynomers®, Centyrins®; and KALBITOR®s. In some embodiments, an antibody may lack a covalent modification (e.g., attachment of a glycan) that it may have if produced naturally. In some embodiments, an antibody may contain a covalent modification (e.g., attachment of a glycan, a payload [e.g., a detectable moiety, a therapeutic moiety, a catalytic moiety, etc.], or other pendant group [e.g., poly-ethylene glycol, etc.]).
Associated: Two events or entities are generally “associated” with one another, as that term is used herein, if the presence, level, degree, type or form of one is correlated with that of the other. For example, a particular entity (e.g., polypeptide, genetic signature, metabolite, microbe, etc.) is considered to be associated with a particular disease, disorder, or condition, if its presence, level or form correlates with incidence of or susceptibility to the disease, disorder, or condition (e.g., across a relevant population). In some embodiments, two or more entities are physically “associated” with one another if they interact, directly or indirectly, so that they are or remain in physical proximity with one another. In some embodiments, two or more entities that are physically associated with one another are covalently linked to one another; in some embodiments, two or more entities that are physically associated with one another are not covalently linked to one another but are non-covalently associated, for example by hydrogen bonds, van der Waals interaction, hydrophobic interactions, magnetism, and combinations thereof.
Biological Sample: As used herein, the term “biological sample” generally refers to a sample obtained or derived from a biological source (e.g., a tissue or organism or cell culture) of interest, as described herein. In some embodiments, a source of interest comprises an organism, such as an animal or human. In some embodiments, a biological sample is or comprises biological tissue or fluid. In some embodiments, a biological sample may be or comprise bone marrow; blood; blood cells; ascites; tissue or fine needle biopsy samples; cell-containing body fluids; free floating nucleic acids; sputum; saliva; urine; cerebrospinal fluid, peritoneal fluid; pleural fluid; feces; lymph; gynecological fluids; skin swabs; vaginal swabs; oral swabs; nasal swabs; washings or lavages such as a ductal lavages or broncheoalveolar lavages; aspirates; scrapings; bone marrow specimens; tissue biopsy specimens; surgical specimens; feces, other body fluids, secretions, or excretions; or cells therefrom, etc. In some embodiments, a biological sample is or comprises cells obtained from an individual. In some embodiments, obtained cells are or include cells from an individual from whom the sample is obtained. In some embodiments, a sample is a “primary sample” obtained directly from a source of interest by any appropriate method. For example, in some embodiments, a primary biological sample is obtained by methods selected from the group consisting of biopsy (e.g., fine needle aspiration or tissue biopsy), surgery, collection of body fluid (e.g., blood, lymph, feces etc.), etc. In some embodiments, the term “sample” refers to a preparation that is obtained by processing (e.g., by removing one or more components of or by adding one or more agents to) a primary sample. For example, filtering using a semi-permeable membrane. Such a “processed sample” may comprise, for example nucleic acids or proteins extracted from a sample or obtained by subjecting a primary sample to techniques such as amplification or reverse transcription of mRNA, isolation or purification of certain components, etc.
Biological Network: As used herein, the term “biological network” generally refers to any network that applies to biological systems, having sub-units (e.g., “nodes”) that are linked into a whole, such as species units linked into a whole web. In some embodiments, a biological network is a protein-protein interaction network (PPI), representing interactions among proteins present in a cell, where proteins are nodes and their interactions are edges. In some embodiments, connections between nodes in a PPI are experimentally verified. In some embodiments, connections between nodes are a combination of experimentally verified a mathematically calculated. In some embodiments, a biological network is a human interactome (a network of experimentally derived interactions that occur in human cells, which includes protein-protein interaction information as well as gene expression and co-expression, cellular co-localization of proteins, genetic information, metabolic and signaling pathways, etc.). In some embodiments, a biological network is a gene regulatory network, a gene co-expression network, a metabolic network, or a signaling network.
Combination Therapy: As used herein, the term “combination therapy” generally refers to a clinical intervention in which a subject is simultaneously exposed to two or more therapeutic regimens (e.g. two or more therapeutic agents). In some embodiments, the two or more therapeutic regimens may be administered simultaneously. In some embodiments, the two or more therapeutic regimens may be administered sequentially (e.g., a first regimen administered prior to administration of any doses of a second regimen). In some embodiments, the two or more therapeutic regimens are administered in overlapping dosing regimens. In some embodiments, administration of combination therapy may involve administration of one or more therapeutic agents or modalities to a subject receiving the other agent(s) or modality. In some embodiments, combination therapy does not necessarily require that individual agents be administered together in a single composition (or even necessarily at the same time). In some embodiments, two or more therapeutic agents or modalities of a combination therapy are administered to a subject separately, e.g., in separate compositions, via separate administration routes (e.g., one agent orally and another agent intravenously), or at different time points. In some embodiments, two or more therapeutic agents may be administered together in a combination composition, or even in a combination compound (e.g., as part of a single chemical complex or covalent entity), via the same administration route, or at the same time.
Comparable: As used herein, the term “comparable” generally refers to two or more agents, entities, situations, sets of conditions, etc., that may not be identical to one another but that are sufficiently similar to permit comparison there between so that conclusions may reasonably be drawn based on differences or similarities observed. In some embodiments, comparable sets of conditions, circumstances, individuals, or populations are characterized by a plurality of substantially identical features and one or a small number of varied features. In various approaches, a different degree of identity may be required in any given circumstance for two or more such agents, entities, situations, sets of conditions, etc. to be considered comparable. For example, in various approaches, different sets of circumstances, individuals, or populations are comparable to one another when characterized by a sufficient number and type of substantially identical features to warrant a reasonable conclusion that differences in results obtained or phenomena observed under or with different sets of circumstances, individuals, or populations are caused by or indicative of the variation in those features that are varied.
Corresponding to: As used herein, the phrase “corresponding to” generally refers to a relationship between two entities, events, or phenomena that share sufficient features to be reasonably comparable such that “corresponding” attributes are apparent. For example, in some embodiments, the term may be used in reference to a compound or composition, to designate the position or identity of a structural element in the compound or composition through comparison with an appropriate reference compound or composition. For example, in some embodiments, a monomeric residue in a polymer (e.g., an amino acid residue in a polypeptide or a nucleic acid residue in a polynucleotide) may be identified as “corresponding to” a residue in an appropriate reference polymer. For example, for purposes of simplicity, residues in a polypeptide are often designated using a canonical numbering system based on a reference related polypeptide, so that an amino acid “corresponding to” a residue at position 190, for example, may not actually be the 190th amino acid in a particular amino acid chain but rather corresponds to the residue found at 190 in the reference polypeptide; various approaches may be used to identify “corresponding” amino acids. For example, various approaches may be used for sequence alignment strategies, including software programs such as, for example, BLAST, CS-BLAST, CUSASW++, DIAMOND, FASTA, GGSEARCH/GLSEARCH, Genoogle, HMMER, HHpred/HHsearch, IDF, Infernal, KLAST, USEARCH, parasail, PSI-BLAST, PSI-Search, ScalaBLAST, Sequilab, SAM, SSEARCH, SWAPHI, SWAPHI-LS, SWIMM, or SWIPE that can be utilized, for example, to identify “corresponding” residues in polypeptides or nucleic acids in accordance with the present disclosure.
Dosing regimen or therapeutic regimen: The terms “dosing regimen” and “therapeutic regimen” may be used to generally refer to a set of unit doses (such as more than one) that are administered individually to a subject, which may be separated by periods of time. In some embodiments, a given therapeutic agent has a recommended dosing regimen, which may involve one or more doses. In some embodiments, a dosing regimen comprises a plurality of doses each of which is separated in time from other doses. In some embodiments, individual doses are separated from one another by a time period of the same length; in some embodiments, a dosing regimen comprises a plurality of doses and at least two different time periods separating individual doses. In some embodiments, all doses within a dosing regimen are of the same unit dose amount. In some embodiments, different doses within a dosing regimen are of different amounts. In some embodiments, a dosing regimen comprises a first dose in a first dose amount, followed by one or more additional doses in a second dose amount different from the first dose amount. In some embodiments, a dosing regimen comprises a first dose in a first dose amount, followed by one or more additional doses in a second dose amount same as the first dose amount. In some embodiments, a dosing regimen is correlated with a beneficial outcome when administered across a relevant population (e.g., is a therapeutic dosing regimen).
Improved, increased or reduced: As used herein, the terms “improved,” “increased,” or “reduced,”, or grammatically comparable comparative terms thereof, generally indicate values that are relative to a comparable reference measurement. For example, in some embodiments, an assessed value achieved with an agent of interest may be “improved” relative to that obtained with a comparable reference agent. Alternatively or additionally, in some embodiments, an assessed value achieved in a subject or system of interest may be “improved” relative to that obtained in the same subject or system under different conditions (e.g., prior to or after an event such as administration of an agent of interest), or in a different, comparable subject (e.g., in a comparable subject or system that differs from the subject or system of interest in presence of one or more indicators of a particular disease, disorder or condition of interest, or in prior exposure to a condition or agent, etc.).
Patient or subject: As used herein, the term “patient” or “subject” generally refers to any organism to which a provided composition is or may be administered, e.g., for experimental, diagnostic, prophylactic, cosmetic, or therapeutic purposes. Some patients or subjects include animals (e.g., mammals such as mice, rats, rabbits, non-human primates, or humans). In some embodiments, a patient is a human. In some embodiments, a patient or a subject is suffering from or susceptible to one or more disorders or conditions. In some embodiments, a patient or subject displays one or more symptoms of a disorder or condition. In some embodiments, a patient or subject has been diagnosed with one or more disorders or conditions. In some embodiments, a patient or a subject is receiving or has received certain therapy to diagnose or to treat a disease, disorder, or condition.
Pharmaceutical composition: As used herein, the term “pharmaceutical composition” generally refers to an active agent, formulated together with one or more pharmaceutically acceptable carriers. In some embodiments, the active agent is present in unit dose amounts appropriate for administration in a therapeutic regimen to a relevant subject (e.g., in amounts that have been demonstrated to show a statistically significant probability of achieving a predetermined therapeutic effect when administered), or in a different, comparable subject (e.g., in a comparable subject or system that differs from the subject or system of interest in presence of one or more indicators of a particular disease, disorder or condition of interest, or in prior exposure to a condition or agent, etc.). In some embodiments, comparative terms refer to statistically relevant differences (e.g., that are of a prevalence or magnitude sufficient to achieve statistical relevance). Various approaches may be used to determine, in a given context, a degree or prevalence of difference that is required or sufficient to achieve such statistical significance.
Pharmaceutically acceptable: As used herein, the phrase “pharmaceutically acceptable” generally refers to those compounds, materials, compositions, or dosage forms which are, within the scope of sound medical judgment, suitable for use in contact with the tissues of human beings and animals without excessive toxicity, irritation, allergic response, or other problem or complication, commensurate with a reasonable benefit/risk ratio.
Prevent or prevention: As used herein, the terms “prevent” or “prevention”, when used in connection with the occurrence of a disease, disorder, or condition, generally refer to reducing the risk of developing the disease, disorder or condition or to delaying onset of one or more characteristics or symptoms of the disease, disorder or condition. Prevention may be considered complete when onset of a disease, disorder or condition has been delayed for a predefined period of time.
Reference: As used herein, the term “reference” generally describes a standard or control relative to which a comparison is performed. For example, in some embodiments, an agent, animal, individual, population, sample, sequence or value of interest is compared with a reference or control agent, animal, individual, population, sample, sequence or value. In some embodiments, a reference or control is tested or determined substantially simultaneously with the testing or determination of interest. In some embodiments, a reference or control is a historical reference or control, optionally embodied in a tangible medium. A reference or control is determined or characterized under comparable conditions or circumstances to those under assessment. Sufficient similarities are present to justify reliance on or comparison to a particular possible reference or control.
Therapeutic agent: As used herein, the phrase “therapeutic agent” generally refers to any agent that elicits a pharmacological effect when administered to an organism. In some embodiments, an agent is considered to be a therapeutic agent if it demonstrates a statistically significant effect across an appropriate population. In some embodiments, the appropriate population may be a population of model organisms. In some embodiments, an appropriate population may be defined by various criteria, such as a certain age group, gender, genetic background, preexisting clinical conditions, etc. In some embodiments, a therapeutic agent is a substance that can be used to alleviate, ameliorate, relieve, inhibit, prevent, delay onset of, reduce severity of, or reduce incidence of one or more symptoms or features of a disease, disorder, or condition. In some embodiments, a “therapeutic agent” is an agent that has been or is required to be approved by a government agency before it can be marketed for administration to humans. In some embodiments, a “therapeutic agent” is an agent for which a medical prescription is required for administration to humans.
Therapeutically effective amount: As used herein, the term “therapeutically effective amount” generally refers to an amount of a substance (e.g, a therapeutic agent, composition, or formulation) that elicits a biological response when administered as part of a therapeutic regimen. In some embodiments, a therapeutically effective amount of a substance is an amount that is sufficient, when administered to a subject suffering from or susceptible to a disease, disorder, or condition, to treat, diagnose, prevent, or delay the onset of the disease, disorder, or condition. The effective amount of a substance may vary depending on such factors as the biological endpoint, the substance to be delivered, the target cell or tissue, etc. For example, the effective amount of compound in a formulation to treat a disease, disorder, or condition is the amount that alleviates, ameliorates, relieves, inhibits, prevents, delays onset of, reduces severity of or reduces incidence of one or more symptoms or features of the disease, disorder or condition. In some embodiments, a therapeutically effective amount is administered in a single dose; in some embodiments, multiple unit doses are required to deliver a therapeutically effective amount.
Treat: As used herein, the terms “treat,” “treatment,” or “treating” generally refer to any method used to partially or completely alleviate, ameliorate, relieve, inhibit, prevent, delay onset of, reduce severity of, or reduce incidence of one or more symptoms or features of a disease, disorder, or condition. Treatment may be administered to a subject who does not exhibit signs of a disease, disorder, or condition. In some embodiments, treatment may be administered to a subject who exhibits early signs of the disease, disorder, or condition, for example, for the purpose of decreasing the risk of developing pathology associated with the disease, disorder, or condition.
Variant: As used herein, the term “variant” generally refers to an entity that shows significant structural identity with a reference entity but differs structurally from the reference entity in the presence or level of one or more chemical moieties as compared with the reference entity. In many embodiments, a variant also differs functionally from its reference entity. In general, whether a particular entity is properly considered to be a “variant” of a reference entity is based on its degree of structural identity with the reference entity. Any biological or chemical reference entity has certain characteristic structural elements. A variant, by definition, is a distinct chemical entity that shares one or more such characteristic structural elements. To give but a few examples, a small molecule may have a characteristic core structural element (e.g., a macrocycle core) or one or more characteristic pendent moieties so that a variant of the small molecule is one that shares the core structural element and the characteristic pendent moieties but differs in other pendent moieties or in types of bonds present (single vs double, E vs Z, etc.) within the core, a polypeptide may have a characteristic sequence element comprised of a plurality of amino acids having designated positions relative to one another in linear or three-dimensional space or contributing to a particular biological function, a nucleic acid may have a characteristic sequence element comprised of a plurality of nucleotide residues having designated positions relative to on another in linear or three-dimensional space. For example, a variant polypeptide may differ from a reference polypeptide as a result of one or more differences in amino acid sequence or one or more differences in chemical moieties (e.g., carbohydrates, lipids, etc.) covalently attached to the polypeptide backbone. In some embodiments, a variant polypeptide shows an overall sequence identity with a reference polypeptide that is at least 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, or 99%. Alternatively or additionally, in some embodiments, a variant polypeptide does not share at least one characteristic sequence element with a reference polypeptide. In some embodiments, the reference polypeptide has one or more biological activities. In some embodiments, a variant polypeptide shares one or more of the biological activities of the reference polypeptide. In some embodiments, a variant polypeptide lacks one or more of the biological activities of the reference polypeptide. In some embodiments, a variant polypeptide shows a reduced level of one or more biological activities as compared with the reference polypeptide. In many embodiments, a polypeptide of interest is considered to be a “variant” of a parent or reference polypeptide if the polypeptide of interest has an amino acid sequence that is identical to that of the parent but for a small number of sequence alterations at particular positions. In some embodiments, fewer than 20%, 15%, 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2% of the residues in the variant are substituted as compared with the parent. In some embodiments, a variant has 10, 9, 8, 7, 6, 5, 4, 3, 2, or 1 substituted residue as compared with a parent. Often, a variant has a very small number (e.g., fewer than 5, 4, 3, 2, or 1) of substituted functional residues (e.g., residues that participate in a particular biological activity). Furthermore, a variant may have not more than 5, 4, 3, 2, or 1 additions or deletions, and often has no additions or deletions, as compared with the parent. Moreover, any additions or deletions may be fewer than about 25, about 20, about 19, about 18, about 17, about 16, about 15, about 14, about 13, about 10, about 9, about 8, about 7, about 6, and commonly are fewer than about 5, about 4, about 3, or about 2 residues. In some embodiments, the parent or reference polypeptide is one found in nature.
The present disclosure provides, among other things, a disease gene expression signature that, when reversed (all or in substantial part), indicates that a subject is responding to a therapy. Such an approach is favorable than other methods, as the presently described methods allow for quantification of response on a molecular level, instead of relying on observing changes in clinical characteristics. Indeed, the present disclosure encompasses an insight that particular molecular signatures, e.g., expression of particular genes, when modulated to resemble healthy subjects, indicate that a diseased subject is responding to a therapy. In some embodiments, a disease expression signature is a pattern of genes that are differentially expressed in diseased subjects as compared to healthy subjects. The presently described disease expression signature accounts for subtle differences between diseased and healthy subjects on a molecular level.
In some embodiments, the present disclosure encompasses an insight that gene expression indicative of response to therapy is not necessarily derived as between subgroups of subjects suffering from the same disease. That is, for example, within a cohort of subjects suffering from a disease, the present disclosure recognizes that analyzing gene expression differences between one or more subgroups of the cohort of subjects may not lead to a gene expression pattern that indicates whether a subject may or may not respond to therapy or otherwise begin to recover from said disease, disorder, or condition. Instead, in some embodiments, the present disclosure analyzes gene expression as between subgroups of diseased subjects having similar gene expression patterns vs. healthy subjects. By analyzing the differences between diseased subjects and healthy subjects, and by identifying key gene expression targets in the diseased subjects that are different from the healthy subjects and also play an important role in driving response, it is understood (without being bound by theory) that modulating the key differentially expressed genes, a diseased subject's gene expression pattern may resemble that of a healthy subject, and thereby lead to regression of the disease.
An example workflow for identifying a disease gene expression signature is seen in
In some embodiments, baseline expression profiles of the subgroups within the cluster are analyzed and compared to one or more healthy control subjects (103). Genes that are differentially expressed are identified, referred to as “disease candidate genes.” In some embodiments, certain genes that are differentially expressed are selected as “disease candidate genes.” In some embodiments, genes that are significantly differentially expressed are selected to be disease candidate genes. In some embodiments, a significant difference in gene expression is measured by a p-value≤0.05 and absolute fold change of 0.5 or more.
In some embodiments, a disease expression signature comprises all, substantially all or a subset of identified disease candidate genes. In some embodiments, disease candidate genes are optionally mapped onto a biological network (104). Without being bound by theory, it is understood that understanding the connectivity of genes within the disease candidate genes allows for identification of the genes of highest relevance, culling out genes that may not have much of an impact of response when treating a subject for a particular disease. For example, in some embodiments, a biological network is a human interactome map. In some embodiments, genes from the set of disease candidate genes that are either significantly connected or otherwise cluster on a human interactome map are selected to be the disease gene expression signature. In some embodiments, all, substantially all, or a subset of disease candidate genes cluster or are significantly connected on a human interactome map. In some embodiments, a disease gene expression signature comprises disease candidate genes that cluster on a biological network (e.g., a human interactome map). In some embodiments, a disease gene expression signature comprises disease candidate genes that are significantly connected to one another on a biological network (e.g., a human interactome map). In some embodiments, the disease candidate genes are mapped onto a biological network before incorporation into the disease gene expression signature.
In some embodiments, a disease gene expression signature is determined by: analyzing gene expression data from a cohort of subjects suffering from the same disease, disorder, or condition as the subject; stratifying the cohort of subjects into two or more groups of prior subjects based on the gene expression data; and selecting one or more genes having significant differences in gene expression between the two or more groups of prior subjects and a group of healthy subjects (e.g., “disease candidate gene”), to thereby provide the disease gene expression signature.
As used herein, a “healthy gene expression signature” refers to gene expression of response genes in healthy control subjects (e.g., subjects who do not suffer from a disease, disorder, or condition as a subject to be treated as described herein).
As described herein, genes of a subject are measured by at least one of a microarray, RNA sequencing, real-time quantitative reverse transcription PCR (qRT-PCR), bead array, ELISA, and protein expression. In some embodiments, gene expression of a subject is measured by subtracting background data, correcting for batch effects, and dividing by mean expression of housekeeping genes. (See e.g., Eisenberg & Levanon, “Human housekeeping genes, revisited,” Trends in Genetics, 29(10):569-574 (October 2013), which is incorporated herein by reference for all purposes). In the context of microarray data analysis, background subtraction refers to subtracting the average fluorescent signal arising from probe features on a chip not complimentary to any mRNA sequence, e.g., signals that arise from non-specific binding, from the fluorescence signal intensity of each probe feature. The background subtraction can be performed with different software packages, such as Affymetrix™ Gene Expression Console. Housekeeping genes are involved in basic cell maintenance and, therefore, are expected to maintain constant expression levels in all cells and conditions. The expression level of genes of interest, e.g., those in the response signature, can be normalized by dividing the expression level by the average expression level across a group of selected housekeeping genes. This housekeeping gene normalization procedure calibrates the gene expression level for experimental variability. Further, normalization methods such as robust multi-array average (“RMA”) correct for variability across different batches of microarrays, are available in R packages recommended by either Illumina™ and/or Affymetrix™ microarray platforms. The normalized data is log transformed, and probes with low detection rates across samples are removed. Furthermore, probes with no available genes symbol or Entrez ID are removed from the analysis.
Among other things, the present disclosure provides a series of protein targets for treatment that, when modulated, impact the disease gene expression signature, causing it to alter expression such that is resembles gene expression of a healthy subject. Further, the present disclosure encompasses an insight that modulation of certain genes via therapy within the disease gene expression signature may not indicate response to said therapy. That is, the present disclosure encompasses an insight that genes within a disease gene expression signature, when modulated directly, can indicate response to therapy, but may not be so strongly connected to one another that a therapy can effectively modulate expression of the genes within the disease gene expression signature for response.
Instead, the present disclosure encompasses an insight that targets either up or downstream from the genes differentially expressed in the disease gene expression signature (as compared to healthy subjects) can be effectively modulated such that their modulation may impact the disease gene expression signature, thereby causing gene expression of a disease subject to resemble that of a healthy subject. In some embodiments, identification of targets for therapy having such a connection to certain genes within a disease gene expression signature is provided in
In some embodiments, targets for therapy are identified that are experimentally shown to cause reversal of a disease gene expression signature. Perturbation of said targets have desirable up or downstream effects, causing disease subject to reach molecular remission (measured by the amount of reversal of the disease gene expression signature to thereby resemble expression of a healthy control). In some embodiments, as seen in
In some embodiments, each gene within a disease gene expression signature is analyzed to identify potential targets for therapy. In some embodiments, certain genes from a disease gene expression signature are selected (“response genes”). In some embodiments, response genes are selected by assigning each gene within a disease gene expression signature a score characterizing their differential expression levels with respect to a baseline control (e.g., as compared to gene expression of a healthy subject). In some embodiments, once a subset of response genes is selected from a disease gene expression signature, response genes are ranked according to their differential expression levels with respect to a baseline control (e.g., as compared to gene expression of a healthy subject). In some embodiments, genes having a connection (e.g., downstream regulation) by a compound from a database of 107 are selected as response genes.
In some embodiments, response genes are selected that have a p-value of 0.05 or less.
Therapies having a significant impact on one or more selected response genes are identified (108) (“potential therapies”). In some embodiments, said potential therapies are those that alter gene expression of a set of response genes. In some embodiments, potential therapies are scored based on significance of alteration of the set of response genes. In some embodiments, therapies having the highest significant of alteration are selected, thereby providing one or more candidate therapies. As used herein, a “therapy” refers to a therapeutic agent as defined here, gene knockout (e.g., making one or more particular genes of a subject inoperative), or gene overexpression (e.g., increasing expression beyond a normal amount of one or more particular genes in a subject).
One or more candidate therapies are assessed to identify which target or targets (e.g., proteins or other cellular functions) each therapy modulates (109). In some embodiments, if there is no relationship between a therapy and a target, said therapy is excluded from the list of candidate therapies. In some embodiments, if there is no relationship between a therapy and a target, then the target is deemed a “novel target”, for which therapy can be developed. One or more potential targets that are directly modulated by the one or more candidate therapies are selected (110). One or more of said potential targets, therefore, can make up a treatment module (112). Optionally, one or more potential targets are mapped onto a biological network, e.g., a human interactome map (111). A subset of potential targets (e.g., targets for therapy) can be assessed and selected based on topological relationships in a biological network (e.g., a human interactome), or based on strength of connection in said biological network. In some embodiments, all potential targets make up a treatment module. In some embodiments, one target is selected for treatment based on having a significant connection to a set of response genes (in a disease gene expression signature). In some embodiments, a significant connection of a target to a set of response genes is whether modulation of said target reverses expression of the set of response genes.
Alternatively, in some embodiments, gene knockout is used to identify one or more targets where knock out of said one or more targets impacts gene expression of one or more of a set of response genes. In some embodiments, targets are scored based on significance of alteration of the set of response genes after knock out. In some embodiments, targets having the highest significance of alteration are selected, thereby providing one or more suitable targets for therapy. In some embodiments, targets identified by gene knockout can be useful for identifying new targets for therapy.
In some embodiments, gene overexpression is used to identify one or more targets where overexpression of said one or more targets impacts gene expression of one or more of a set of response genes. In some embodiments, targets are scored based on significance of alteration of the set of response genes after overexpression. In some embodiments, targets having the highest significance of alteration are selected, thereby providing one or more suitable targets for therapy. In some embodiments, targets identified by gene overexpression can be useful for identifying new targets for therapy.
As described, potential targets, or a subset thereof (113) are assessed to identify targets having no experimentally validated treatments available. In some embodiments, novel targets are selected within the identified treatment module. In some embodiments, novel targets are identified as those having a substantial impact similarity to potential targets (e.g., a treatment module), and ability to reverse gene expression of the set of response genes. As described herein, a “novel target” refers to a protein or other cellular mechanism for which no therapy (or no substantially effective therapy) is available. Such novel targets offer promising goals for drug development, as they provide options for targets for treatment that have not necessarily been considered to date.
Novel targets can be identified in a variety of ways from the potential targets (or a treatment module), as described herein. For example, in some embodiments, diffusion state distance (DSD), a metric based on graph diffusion property, is designed to capture finer-grained distinctions in proximity for transfer of functional annotation in biological networks (e.g., protein-protein interaction network, or a human interactome). In some embodiments, such proximity for transfer is assessed by a machine learning process method. In some embodiments, a machine learning process method is a diffusion-based method such as random walk. In some embodiments, a random walk traverses vertices of the biological network, and assessed the closeness of two states (or, nodes) u and v by comparing the expected number of visits to all states (within a given time horizon) when the initial state is u and when the initial state is v. Without being bound by theory, it is understood that two nodes having small DSD have high downstream impact similarity.
In some embodiments, perturbing targets for therapy (e.g., a treatment module) results in desirable downstream effect in response module genes and treat the patients. By way of example, anti-TNF therapies target TNF, and approved for treatment of certain autoimmune diseases, e.g., ulcerative colitis, rheumatoid arthritis, etc. A treatment module (e.g., targets for therapy) can be compared to TNF to determine their impact similarity as compared to random expectation by a machine learning process method. For example, using diffusion state difference (DSD) for 1000 iterations, the similarity between TNF and the treatment module is determined by calculating the average DSD value between TNF and every single node in the treatment module (e.g., every single target for therapy). The similarity between randomized treatment module and TNF is determined by calculating the average DSD value between randomized treatment module (e.g., nodes selected at random having similar degrees) and TNF. Network similarity analysis shows that: TNF has significantly closer network similarity to experimentally derived treatment module than to randomly selected treatment module (
Accordingly, in some embodiments, the present disclosure provides a method of determining or validating a target for therapy for treating a subject suffering from a disease, disorder, or condition, the method comprising: receiving a set of response genes corresponding to a disease gene expression signature, wherein the disease gene expression signature is or comprises one or more genes that, when expression is reversed in whole or in part, resembles gene expression of a healthy subject; receiving a plurality of interactions between one or more potential therapies and a plurality of gene expressions; generating for each gene of the set of response genes, one or more potential therapies that alter gene expression of the set of response genes; scoring each of the one or more potential therapies based on significance of alteration (e.g., the change in gene expression) of the set of response genes, to thereby provide one or more candidate therapies; determining one or more potential targets directly modulated by the one or more candidate therapies; mapping each of the one or more potential targets onto a biological network; adding secondary targets sharing significant topological similarity (e.g., are close in proximity or otherwise are similarly positioned on a biological network) to the one or more potential targets on the biological network to a list of targets comprising the one or m ore potential targets and any secondary targets; identifying a target having a significant downstream impact to the set of response genes from the list of targets to provide the target for therapy.
In some embodiments, a secondary target is a target that is connected, either directly, or indirectly (e.g., one or two or three operations removed) from a target from the one or more potential targets. In some embodiments, a secondary target is a target having
The present disclosure, among other things, encompasses an insight that network-based measures of selectivity and specificity can be used to identify a treatment module and rank and identify novel targets as well as repurposing opportunities.
Among other things, the present disclosure provides methods of treating a subject suffering from a disease using a therapy that targets one or more of the targets for treatment as described above. For example, in some embodiments, the present disclosure provides a method of treating a subject that exhibits a disease gene expression signature, the method comprising administering a therapy determined to revert (or reverse, or otherwise alter) the disease gene expression signature to resemble a healthy gene expression signature, wherein the therapy has been determined by: selecting a set of response genes from the disease gene expression signature; identifying one or more potential therapies that alter gene expression of the set of response genes; scoring each of the one or more potential therapies based on significance of alteration of the set of response genes to provide one or more candidate therapies; determining one or more potential targets directly modulated by the one or more candidate therapies; selecting a target for treatment from the one or more potential targets by identifying a target having a significant topological similarity (e.g., being in close proximity on a biological network) to the set of response genes; and identifying the therapy that directly modulates the target for treatment.
In some embodiments, disease gene expression signature is determined by analyzing gene expression data from a cohort of subjects suffering from the same disease, disorder, or condition as the subject, stratifying the cohort of subjects into two or more groups of prior subjects based on the gene expression data; and selecting one or more genes having significant differences in gene expression between the two or more groups of prior subjects and a group of healthy subjects (“disease candidate genes”), to thereby provide the disease gene expression signature.
In some embodiments, stratifying a cohort of prior subjects into two or more groups comprises stratifying subjects based on whether the prior subjects are responders or non-responders to a particular therapy (e.g., an anti-TNF therapy). In some embodiments, prior subjects are stratified randomly. In some embodiments, prior subjects are stratified by similarities based on gene expression. In some embodiments, similarities based on gene expression in prior subjects are analyzed by a machine learning process.
In some embodiments, a therapy is selected from Table 1.
In some embodiments, a therapy is an anti-TNF therapy. In some embodiments, an anti-TNF therapy is selected from infliximab, etanercept, adalimumab, certolizumab pegol, golimumab, and biosimilars thereof. In some embodiments, an anti-TNF therapy is infliximab. In some embodiments, an anti-TNF therapy is etanercept. In some embodiments, an anti-TNF therapy is adalimumab. In some embodiments, an anti-TNF therapy is certolizumab pegol. In some embodiments, an anti-TNF therapy is golimumab. In some embodiments, an anti-TNF therapy is a biosimilar of infliximab, etanercept, adalimumab, certolizumab pegol, or golimumab.
In some embodiments, a therapy is selected from rituximab, sarilumab, tofacitinib citrate, lefunomide, vedolizumab, tocilizumab, anakinra, and abatacept. In some embodiments, a therapy is rituximab. In some embodiments, a therapy is sarilumab. In some embodiments, a therapy is tofacitinib citrate. In some embodiments, a therapy is lefunomide. In some embodiments, a therapy is vedolizumab. In some embodiments, a therapy is tocilizumab. In some embodiments, a therapy is anakinra. In some embodiments, a therapy is abatacept.
In some embodiments, a disease, disorder, or condition is selected from ulcerative colitis, Crohn's disease, rheumatoid arthritis, juvenile arthritis, psoriatic arthritis, plaque psoriasis, and ankylosing spondylitis. In some embodiments, a disease, disorder, or condition is ulcerative colitis. In some embodiments, a disease, disorder, or condition is Crohn's disease. In some embodiments, a disease, disorder, or condition is rheumatoid arthritis. In some embodiments, a disease, disorder, or condition is ulcerative colitis, Crohn's disease, rheumatoid arthritis, juvenile arthritis, psoriatic arthritis, plaque psoriasis, and ankylosing spondylitis.
In some embodiments, the one or more potential targets is selected from JAK1, JAK2, JAK3, IL23A, ITGA4, ITGB7, IL2RA, IL12A, IL12B, TNF, IL12RB1, IL23R, IL12RB2, and MADCAM1.
Further, the present disclosure provides technologies for monitoring therapy for a given subject or cohort of subjects. As a subject's gene expression level can change over time, it may, in some instances, be desirable to evaluate a subject at one or more points in time, for example, at specified and or periodic intervals.
In some embodiments, repeated monitoring under time permits or achieves detection of one or more changes in a subject's gene expression profile or characteristics that may impact ongoing treatment regimens. In some embodiments, a change is detected in response to which particular therapy administered to the subject is continued, is altered, or is suspended. In some embodiments, therapy may be altered, for example, by increasing or decreasing frequency or amount of administration of one or more agents or treatments with which the subject is already being treated. Alternatively or additionally, in some embodiments, therapy may be altered by addition of therapy with one or more new agents or treatments. In some embodiments, therapy may be altered by suspension or cessation of one or more particular agents or treatments.
Also described herein is a method for engineering a personalized therapy for a subject, the method comprising: receiving or generating a disease gene expression signature comprising a set of response genes; receiving or generating a set of one or more potential therapies that alter expression of the one or more response genes; ranking each of the set of the one or more potential therapies according to significance of alteration of the one or more response genes, to provide a set of one or more candidate therapies; determining one or more potential targets directly modulated by the set of one or more candidate therapies, optionally by mapping the one or more potential targets onto a biological network; ranking significance of downstream impact (e.g., diffusion state distance) between each of the one or more potential targets and the set of response genes; selecting a target for treatment from the one or more potential targets; and selecting the personalized therapy that modulates the target for treatment.
In some embodiments, a disease gene expression signature is determined by: receiving or generating gene expression data from a cohort of subjects suffering from the same disease, disorder, or condition as the subject; stratifying the cohort of subjects into two or more groups of prior subjects based on the gene expression data; and selecting one or more genes having significant differences in gene expression between the two or more groups of prior subjects and a group of healthy subjects (“disease candidate genes”), to thereby provide the disease gene expression signature.
In some embodiments, disease candidate genes are mapped onto a biological network before being selected to be part of the disease gene expression signature.
In some embodiments, determining one or more potential targets further comprises mapping targets of the one or more candidate therapies onto a biological network, and selecting potential targets based on topological information provided by to the biological network.
In some embodiments, ranking of each of the one or more potential therapies comprises: calculating a difference in expression level of the set of response genes after treatment with the one or more potential therapies relative to the set of response genes before treatment with the one or more potential therapies; and calculating a p-value for each of the one or more potential therapies.
In some embodiments, potential targets are identified by a machine-learning process.
In some embodiments, a machine-learning process is random walk.
As shown in
The cloud computing environment 400 may include a resource manager 406. The resource manager 406 may be connected to the resource providers 402 and the computing devices 404 over the computer network 408. In some implementations, the resource manager 406 may facilitate the provision of computing resources by one or more resource providers 402 to one or more computing devices 404. The resource manager 406 may receive a request for a computing resource from a particular computing device 404. The resource manager 406 may identify one or more resource providers 402 capable of providing the computing resource requested by the computing device 404. The resource manager 406 may select a resource provider 402 to provide the computing resource. The resource manager 406 may facilitate a connection between the resource provider 402 and a particular computing device 404. In some implementations, the resource manager 406 may establish a connection between a particular resource provider 402 and a particular computing device 404. In some implementations, the resource manager 406 may redirect a particular computing device 404 to a particular resource provider 402 with the requested computing resource.
The computing device 500 includes a processor 502, a memory 504, a storage device 506, a high-speed interface 508 connecting to the memory 504 and multiple high-speed expansion ports 510, and a low-speed interface 512 connecting to a low-speed expansion port 514 and the storage device 506. Each of the processor 502, the memory 504, the storage device 506, the high-speed interface 508, the high-speed expansion ports 510, and the low-speed interface 512, are interconnected using various busses, and may be mounted on a common motherboard or in other manners as appropriate. The processor 502 can process instructions for execution within the computing device 500, including instructions stored in the memory 504 or on the storage device 506 to display graphical information for a GUI on an external input/output device, such as a display 516 coupled to the high-speed interface 508. In other implementations, multiple processors or multiple buses may be used, as appropriate, along with multiple memories and types of memory. Also, multiple computing devices may be connected, with each device providing portions of the operations (e.g., as a server bank, a group of blade servers, or a multi-processor system). Thus, as the term is used herein, where a plurality of functions are described as being performed by “a processor”, this encompasses embodiments wherein the plurality of functions are performed by any number of processors (one or more) of any number of computing devices (one or more). Furthermore, where a function is described as being performed by “a processor”, this encompasses embodiments wherein the function is performed by any number of processors (one or more) of any number of computing devices (one or more) (e.g., in a distributed computing system).
The memory 504 stores information within the computing device 500. In some implementations, the memory 504 is a volatile memory unit or units. In some implementations, the memory 504 is a non-volatile memory unit or units. The memory 504 may also be another form of computer-readable medium, such as a magnetic or optical disk.
The storage device 506 is capable of providing mass storage for the computing device 500. In some implementations, the storage device 506 may be or contain a computer-readable medium, such as a floppy disk device, a hard disk device, an optical disk device, or a tape device, a flash memory or other similar solid state memory device, or an array of devices, including devices in a storage area network or other configurations. Instructions can be stored in an information carrier. The instructions, when executed by one or more processing devices (for example, processor 502), perform one or more methods, such as those described above. The instructions can also be stored by one or more storage devices such as computer- or machine-readable mediums (for example, the memory 504, the storage device 506, or memory on the processor 502).
The high-speed interface 508 manages bandwidth-intensive operations for the computing device 500, while the low-speed interface 512 manages lower bandwidth-intensive operations. Such allocation of functions is an example. In some implementations, the high-speed interface 508 is coupled to the memory 504, the display 516 (e.g., through a graphics processor or accelerator), and to the high-speed expansion ports 510, which may accept various expansion cards (not shown). In the implementation, the low-speed interface 512 is coupled to the storage device 506 and the low-speed expansion port 514. The low-speed expansion port 514, which may include various communication ports (e.g., USB, Bluetooth®, Ethernet, wireless Ethernet) may be coupled to one or more input/output devices, such as a keyboard, a pointing device, a scanner, or a networking device such as a switch or router, e.g., through a network adapter.
The computing device 500 may be implemented in a number of different forms, as shown in
The mobile computing device 550 includes a processor 552, a memory 564, an input/output device such as a display 554, a communication interface 566, and a transceiver 568, among other components. The mobile computing device 550 may also be provided with a storage device, such as a micro-drive or other device, to provide additional storage. Each of the processor 552, the memory 564, the display 554, the communication interface 566, and the transceiver 568, are interconnected using various buses, and several of the components may be mounted on a common motherboard or in other manners as appropriate.
The processor 552 can execute instructions within the mobile computing device 550, including instructions stored in the memory 564. The processor 552 may be implemented as a chipset of chips that include separate and multiple analog and digital processors. The processor 552 may provide, for example, for coordination of the other components of the mobile computing device 550, such as control of user interfaces, applications run by the mobile computing device 550, and wireless communication by the mobile computing device 550.
The processor 552 may communicate with a user through a control interface 558 and a display interface 556 coupled to the display 554. The display 554 may be, for example, a TFT (Thin-Film-Transistor Liquid Crystal Display) display or an OLED (Organic Light Emitting Diode) display, or other appropriate display technology. The display interface 556 may comprise appropriate circuitry for driving the display 554 to present graphical and other information to a user. The control interface 558 may receive commands from a user and convert them for submission to the processor 552. In addition, an external interface 562 may provide communication with the processor 552, so as to enable near area communication of the mobile computing device 550 with other devices. The external interface 562 may provide, for example, for wired communication in some implementations, or for wireless communication in other implementations, and multiple interfaces may also be used.
The memory 564 stores information within the mobile computing device 550. The memory 564 can be implemented as one or more of a computer-readable medium or media, a volatile memory unit or units, or a non-volatile memory unit or units. An expansion memory 574 may also be provided and connected to the mobile computing device 550 through an expansion interface 572, which may include, for example, a SIMM (Single In Line Memory Module) card interface. The expansion memory 574 may provide extra storage space for the mobile computing device 550, or may also store applications or other information for the mobile computing device 550. Specifically, the expansion memory 574 may include instructions to carry out or supplement the processes described above, and may include secure information also. Thus, for example, the expansion memory 574 may be provide as a security module for the mobile computing device 550, and may be programmed with instructions that permit secure use of the mobile computing device 550. In addition, secure applications may be provided via the SIMM cards, along with additional information, such as placing identifying information on the SIMM card in a non-hackable manner.
The memory may include, for example, flash memory or NVRAM memory (non-volatile random access memory), as discussed below. In some implementations, instructions are stored in an information carrier, that the instructions, when executed by one or more processing devices (for example, processor 552), perform one or more methods, such as those described above. The instructions can also be stored by one or more storage devices, such as one or more computer- or machine-readable mediums (for example, the memory 564, the expansion memory 574, or memory on the processor 552). In some implementations, the instructions can be received in a propagated signal, for example, over the transceiver 568 or the external interface 562.
The mobile computing device 550 may communicate wirelessly through the communication interface 566, which may include digital signal processing circuitry where necessary. The communication interface 566 may provide for communications under various modes or protocols, such as GSM voice calls (Global System for Mobile communications), SMS (Short Message Service), EMS (Enhanced Messaging Service), or MMS messaging (Multimedia Messaging Service), CDMA (code division multiple access), TDMA (time division multiple access), PDC (Personal Digital Cellular), WCDMA (Wideband Code Division Multiple Access), CDMA2000, or GPRS (General Packet Radio Service), among others. Such communication may occur, for example, through the transceiver 568 using a radio-frequency. In addition, short-range communication may occur, such as using a Bluetooth®, Wi-Fi™, or other such transceiver (not shown). In addition, a GPS (Global Positioning System) receiver module 570 may provide additional navigation- and location-related wireless data to the mobile computing device 550, which may be used as appropriate by applications running on the mobile computing device 550.
The mobile computing device 550 may also communicate audibly using an audio codec 560, which may receive spoken information from a user and convert it to usable digital information. The audio codec 560 may likewise generate audible sound for a user, such as through a speaker, e.g., in a handset of the mobile computing device 550. Such sound may include sound from voice telephone calls, may include recorded sound (e.g., voice messages, music files, etc.) and may also include sound generated by applications operating on the mobile computing device 550.
The mobile computing device 550 may be implemented in a number of different forms, as shown in
Various implementations of the systems and techniques described here can be realized in digital electronic circuitry, integrated circuitry, specially designed ASICs (application specific integrated circuits), computer hardware, firmware, software, or combinations thereof. These various implementations can include implementation in one or more computer programs that are executable or interpretable on a programmable system including at least one programmable processor, which may be special or general purpose, coupled to receive data and instructions from, and to transmit data and instructions to, a storage system, at least one input device, and at least one output device.
These computer programs (e.g., programs, software, software applications or code) include machine instructions for a programmable processor, and can be implemented in a high-level procedural or object-oriented programming language, or in assembly/machine language. As used herein, the terms machine-readable medium and computer-readable medium refer to any computer program product, apparatus or device (e.g., magnetic discs, optical disks, memory, Programmable Logic Devices (PLDs)) used to provide machine instructions or data to a programmable processor, including a machine-readable medium that receives machine instructions as a machine-readable signal. The term machine-readable signal refers to any signal used to provide machine instructions or data to a programmable processor.
To provide for interaction with a user, the systems and techniques described here can be implemented on a computer having a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to the user and a keyboard and a pointing device (e.g., a mouse or a trackball) by which the user can provide input to the computer. Other kinds of devices can be used to provide for interaction with a user as well; for example, feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user can be received in any form, including acoustic, speech, or tactile input.
The systems and techniques described here can be implemented in a computing system that includes a back end component (e.g., as a data server), or that includes a middleware component (e.g., an application server), or that includes a front end component (e.g., a client computer having a graphical user interface or a Web browser through which a user can interact with an implementation of the systems and techniques described here), or any combination of such back end, middleware, or front end components. The components of the system can be interconnected by any form or medium of digital data communication (e.g., a communication network). Examples of communication networks include a local area network (LAN), a wide area network (WAN), and the Internet.
The computing system can include clients and servers. A client and server may be remote from each other and may interact through a communication network. The relationship of client and server arises by virtue of computer programs running on the respective computers and having a client-server relationship to each other.
In some implementations, the modules described herein can be separated, combined or incorporated into single or combined modules. The modules depicted in the figures are not intended to limit the systems described herein to the software architectures shown therein.
Elements of different implementations described herein may be combined to form other implementations not specifically set forth above. Elements may be left out of the processes, computer programs, databases, etc. described herein without adversely affecting their operation. In addition, the logic flows depicted in the figures do not require the particular order shown, or sequential order, to achieve desirable results. Various separate elements may be combined into one or more individual elements to perform the functions described herein. In view of the structure, functions and apparatus of the systems and methods described here, in some implementations.
The present disclosure provides computer systems that are programmed to implement methods of the disclosure.
The computer system 1401 includes a central processing unit (CPU, also “processor” and “computer processor” herein) 1405, which can be a single core or multi core processor, or a plurality of processors for parallel processing. The computer system 1401 also includes memory or memory location 1410 (e.g., random-access memory, read-only memory, flash memory), electronic storage unit 1415 (e.g., hard disk), communication interface 1420 (e.g., network adapter) for communicating with one or more other systems, and peripheral devices 1425, such as cache, other memory, data storage and/or electronic display adapters. The memory 1410, storage unit 1415, interface 1420 and peripheral devices 1425 are in communication with the CPU 1405 through a communication bus (solid lines), such as a motherboard. The storage unit 1415 can be a data storage unit (or data repository) for storing data. The computer system 1401 can be operatively coupled to a computer network (“network”) 1430 with the aid of the communication interface 1420. The network 1430 can be the Internet, an internet and/or extranet, or an intranet and/or extranet that is in communication with the Internet. The network 1430 in some cases is a telecommunication and/or data network. The network 1430 can include one or more computer servers, which can enable distributed computing, such as cloud computing. The network 1430, in some cases with the aid of the computer system 1401, can implement a peer-to-peer network, which may enable devices coupled to the computer system 1401 to behave as a client or a server.
The CPU 1405 can execute a sequence of machine-readable instructions, which can be embodied in a program or software. The instructions may be stored in a memory location, such as the memory 1410. The instructions can be directed to the CPU 1405, which can subsequently program or otherwise configure the CPU 1405 to implement methods of the present disclosure. Examples of operations performed by the CPU 1405 can include fetch, decode, execute, and writeback.
The CPU 1405 can be part of a circuit, such as an integrated circuit. One or more other components of the system 1401 can be included in the circuit. In some cases, the circuit is an application specific integrated circuit (ASIC).
The storage unit 1415 can store files, such as drivers, libraries and saved programs. The storage unit 1415 can store user data, e.g., user preferences and user programs. The computer system 1401 in some cases can include one or more additional data storage units that are external to the computer system 1401, such as located on a remote server that is in communication with the computer system 1401 through an intranet or the Internet.
The computer system 1401 can communicate with one or more remote computer systems through the network 1430. For instance, the computer system 1401 can communicate with a remote computer system of a user (e.g., a medical professional or patient). Examples of remote computer systems include personal computers (e.g., portable PC), slate or tablet PC's (e.g., Apple® iPad, Samsung® Galaxy Tab), telephones, Smart phones (e.g., Apple® iPhone, Android-enabled device, Blackberry®), or personal digital assistants. The user can access the computer system 1401 via the network 1430.
Methods as described herein can be implemented by way of machine (e.g., computer processor) executable code stored on an electronic storage location of the computer system 1401, such as, for example, on the memory 1410 or electronic storage unit 1415. The machine executable or machine readable code can be provided in the form of software. During use, the code can be executed by the processor 1405. In some cases, the code can be retrieved from the storage unit 1415 and stored on the memory 1410 for ready access by the processor 1405. In some situations, the electronic storage unit 1415 can be precluded, and machine-executable instructions are stored on memory 1410.
The code can be pre-compiled and configured for use with a machine having a processer adapted to execute the code, or can be compiled during runtime. The code can be supplied in a programming language that can be selected to enable the code to execute in a pre-compiled or as-compiled fashion.
Aspects of the systems and methods provided herein, such as the computer system 1401, can be embodied in programming. Various aspects of the technology may be thought of as “products” or “articles of manufacture” typically in the form of machine (or processor) executable code and/or associated data that is carried on or embodied in a type of machine readable medium. Machine-executable code can be stored on an electronic storage unit, such as memory (e.g., read-only memory, random-access memory, flash memory) or a hard disk. “Storage” type media can include any or all of the tangible memory of the computers, processors or the like, or associated modules thereof, such as various semiconductor memories, tape drives, disk drives and the like, which may provide non-transitory storage at any time for the software programming. All or portions of the software may at times be communicated through the Internet or various other telecommunication networks. Such communications, for example, may enable loading of the software from one computer or processor into another, for example, from a management server or host computer into the computer platform of an application server. Thus, another type of media that may bear the software elements includes optical, electrical and electromagnetic waves, such as used across physical interfaces between local devices, through wired and optical landline networks and over various air-links. The physical elements that carry such waves, such as wired or wireless links, optical links or the like, also may be considered as media bearing the software. As used herein, unless restricted to non-transitory, tangible “storage” media, terms such as computer or machine “readable medium” refer to any medium that participates in providing instructions to a processor for execution.
Hence, a machine readable medium, such as computer-executable code, may take many forms, including but not limited to, a tangible storage medium, a carrier wave medium or physical transmission medium. Non-volatile storage media include, for example, optical or magnetic disks, such as any of the storage devices in any computer(s) or the like, such as may be used to implement the databases, etc. shown in the drawings. Volatile storage media include dynamic memory, such as main memory of such a computer platform. Tangible transmission media include coaxial cables; copper wire and fiber optics, including the wires that comprise a bus within a computer system. Carrier-wave transmission media may take the form of electric or electromagnetic signals, or acoustic or light waves such as those generated during radio frequency (RF) and infrared (IR) data communications. Common forms of computer-readable media therefore include for example: a floppy disk, a flexible disk, hard disk, magnetic tape, any other magnetic medium, a CD-ROM, DVD or DVD-ROM, any other optical medium, punch cards paper tape, any other physical storage medium with patterns of holes, a RAM, a ROM, a PROM and EPROM, a FLASH-EPROM, any other memory chip or cartridge, a carrier wave transporting data or instructions, cables or links transporting such a carrier wave, or any other medium from which a computer may read programming code and/or data. Many of these forms of computer readable media may be involved in carrying one or more sequences of one or more instructions to a processor for execution.
The computer system 1401 can include or be in communication with an electronic display 1435 that comprises a user interface (UI) 1440 for providing, for example, an input or output of data, or an visual output relating to an algorithm. Examples of UI's include, without limitation, a graphical user interface (GUI) and web-based user interface.
Methods and systems of the present disclosure can be implemented by way of one or more algorithms. An algorithm can be implemented by way of software upon execution by the central processing unit 1405. The algorithm can, for example, perform analysis or operations of methods of the present disclosure.
The following non-limiting examples are intended to illustrate various embodiments of the subject matter described herein.
Gene expression data of eight ulcerative colitis (UC) patient cohorts that went through anti-TNF therapy where downloaded and studied in two separate batches (Study 1 and Study 2 described in Table 2 and Table 3, respectively).
Gene expression profile of responders and non-responders to treatment at baseline and after treatment when compared to each other and to healthy controls (
Molecular differences of a specific disease subpopulations are subtle. Comparing baseline expression profiles of UC responders and non-responders does not reveal any significantly differentiated genes. Instead, molecular differences of patient subpopulations are more pronounced when compared to healthy controls.
Gene expression of non-responders were derived by comparing the baseline expression profile of non-responders to healthy controls. The inverse was also performed (e.g., comparing baseline expression profile of responders to healthy controls). Both studies showed that responder biomarker set is almost fully contained within non-responders' biomarker set and non-responder biomarker set was generally twice lager than responder biomarker set, potentially suggesting a more severe disease state for non-responders (
For example, in some embodiments, in response module discovery, biomarkers associated to specific patient subpopulations are identified as compared to healthy controls. In order to achieve molecular remission e.g., making patient's transcriptomics resemble healthy controls, a desirable downstream effect is identified, where the response module genes are reversed.
In treatment module discovery, for example, in some embodiments, existing targets are identified that are experimentally shown to result in reversing the expression profile of response module genes. Therefore, an identified treatment module includes promising targets whose perturbations carry the desirable downstream effect, causing patients to reach molecular remission.
In order to identify novel targets, network-based downstream similarity (impact similarity) measure of Diffusion-State-Distance (DSD) was used. Novel targets were identified based on their downstream similarity (specificity) to the identified treatment module and its significance (selectivity). It was found that protein targets of different drugs approved for an indication, tend to have highly significant impact similarity to each other.
Subjects were be stratified using both supervised and unsupervised clustering algorithms. To identify subject subpopulation biomarkers, baseline expression profile of different patient subpopulations was compared to healthy controls. These biomarkers are then mapped on the map of Human Interactome. It was found that identified biomarkers form a significant cluster on the network e.g., the nodes are not scattered and instead are significantly interacting with each other forming a subnetwork consisting subpopulation-specific biomarkers (response module). It was also discovered that after-treatment expression profile of patients who responded to treatment resemble healthy controls and so response to treatment can be translated to reverting the response module genes to make them resemble healthy controls.
A treatment module is a set of gene targets that are experimentally shown to revert the expression of biomarker genes identified in the response module. Treatment module discovery pipeline comprises one or more of the following data sets as inputs:
The following exemplary operations were used to develop a treatment module:
Diffusion state distance (DSD), a metric based on graph diffusion property, designed to capture finer-grained distinctions in proximity for transfer of functional annotation in biological networks (e.g., a protein-protein interaction network, or a human interactome network). A random walk on the vertices of the graph was used to assess the closeness of two states u and v by comparing the expected number of visits to all states (within a given time horizon) when the initial state is u and when the initial state is v. Two nodes with small DSD have high downstream impact similarity.
Perturbing a treatment module results in desirable downstream effect in response module genes and treat the subjects. TNF was studied to prove this concept. TNF is an approved target for UC patients. To validate a treatment module, network-based downstream impact similarity to TNF was assessed. First, impact similarity between TNF and the treatment module was compared to random expectation where the treatment module was randomly chosen from the network 1000 times. The similarity between TNF and the treatment module is determined by calculating the average DSD value between the TNF and every single node in the treatment module. The similarity between randomized treatment module and TNF is determined by calculating the average DSD value between randomized treatment module as compared to TNF.
A randomized treatment module was selected by randomly picking targets with similar degrees as the treatment module target. This randomization was repeated for 1000 iterations, thereby providing a distribution of 1000 similarity values quantifying the similarity between randomized treatment module and TNF. Network similarity analysis shows that: TNF has significantly closer network similarity to experimentally derived treatment module than to randomly selected treatment module (
Tumor necrosis factor-α inhibitors (TNFi) have been a standard treatment in ulcerative colitis (UC) for nearly 20 years. However, not every patient responds to TNFi therapies, inciting development of alternative UC treatments. Disclosed herein are multi-omic network biology methods for prioritization of protein targets for UC treatment. Disclosed methods may identify network modules on a Human Interactome comprising genes contributing to a predisposition to UC (a Genotype module), genes whose expression may be altered to achieve low disease activity (a Response module), and proteins whose perturbation may alter expression of the Response module genes in a favorable direction (a Treatment module). Targets may be prioritized based on their topological relevance to the Genotype module and functional similarity to the Treatment module. In an example, methods described herein in UC may efficiently recover protein targets associated with launched and underdevelopment drugs for UC treatment. Avenues may be enabled for finding novel and repurposing therapeutic opportunities in UC and other complex diseases.
Ulcerative colitis (UC) is a complex disease characterized by chronic intestinal inflammation and is thought to be caused by an abnormal immune response to intestinal microbiota in genetically predisposed patients. (See e.g., C. Abraham et al., “Inflammatory Bowel Disease,” New England Journal of Medicine 361, 2066 (2009), which is incorporated herein by reference for all purposes). Treatment of UC may include aminosalicylates and steroids and, if low disease activity is not achieved, biologics such as tumor necrosis factor-α inhibitors (TNFi) may be recommended. (See e.g., S. C. Park et al., “Current and emerging biologics for ulcerative colitis,” Gut and liver 9, 18 (2015); K. Hazel et al., Emerging treatments for inflammatory bowel disease, “Therapeutic advances in chronic disease.” 11, 2040622319899297 (2020), which are incorporated herein by reference for all purposes). Nonetheless, about 40% of patients may be unresponsive to TNFi treatment, and up to 10% of initial responders may lose their response to TNFi therapy each year. (See e.g., S. C. Park et al.; P. Rutgeerts et al., “Infliximab for induction and maintenance therapy for ulcerative colitis,” New England Journal of Medicine 353, 2462 (2005), which are incorporated herein by reference for all purposes). Difficulties with TNFi therapies along with financial incentives led to research and development of alternative therapeutic approaches, for example, JAK inhibitors, IL-12/IL-23 inhibitors, S1P-receptor modulators, anti-integrin agents, or novel TNFi compounds. (See e.g., E. Troncone et al., “Novel therapeutic options for people with ulcerative colitis: an update on recent developments with Janus kinase (JAK) inhibitors,” Clinical and Experimental Gastroenterology 13, 131 (2020); A. Kashani et al., “The Expanding Role of Anti-IL-12 and/or Anti-IL-23 Antibodies in the Treatment of Inflammatory Bowel Disease,” Gastroenterology & Hepatology 15, 255 (2019); S. Danese et al., “Targeting S1P in inflammatory bowel disease: new avenues for modulating intestinal leukocyte migration,” Journal of Crohn's and Colitis 12, S678 (2018); S. C. Park et al., “Anti-integrin therapy for inflammatory bowel disease,” World journal of gastroenterology 24, 1868 (2018); K. Hazel et al., which are incorporated herein by reference for all purposes). Some approaches target biological mechanisms contributing to aberrant immune response and may require detailed knowledge about UC pathogenesis. However, due to concerns around immunogenicity and inconvenience of drug delivery through injections, there is an increasing interest in development of additional orally administered small molecule drugs.
Development of novel drugs may require identification of molecular targets whose modulation may lead to low disease activity or remission. With the surge in multi-omic data, machine learning (ML) and artificial intelligence (AI) became widely used for many tasks in therapeutics such as target prioritization, drug design, drug target interaction prediction, or small molecule optimization. (See e.g., J. Vamathevan et al., “Applications of machine learning in drug discovery and development,” Nature reviews Drug discovery 18, 463 (2019), which is incorporated herein by reference for all purposes). Current ML/AI approaches for target prioritization may focus on searching for genes involved in a given disease. Genes may be inferred by e.g., training classifiers using features constructed from a disease-specific gene expression and mutation data, along with information about relevant protein-protein, metabolic, or transcriptional interactions, or by analyzing existing textual databases or research literature for disease-genes associations using natural language processing (NLP) methods. (See e.g., P. R. Costa et al., in BMC Genomics, Vol. 11 (Springer, 2010) pp. 1-15; J. Jeon et al., “A systematic approach to identify novel cancer drug targets using machine learning, inhibitor design and high-throughput screening,” Genome medicine 6, 1 (2014); E. Ferrero et al., “In silico prediction of novel therapeutic targets using gene-disease association data,” Journal of translational medicine 15, 1 (2017); P. Mamoshina et al., “Machine learning on human muscle transcriptomic data for biomarker discovery and tissue-specific drug target identification,” Frontiers in genetics 9, 242 (2018); A. Bravo et al., “Extraction of relations between genes and diseases from text and large-scale data analysis: implications for translational research,” BMC Bioinformatics 16, 1 (2015); J. Kim et al., “An analysis of disease-gene relationship from Medline abstracts by DigSee,” Scientific Reports 7, 1 (2017), which are incorporated herein by reference for all purposes).
Yet, many ML/AI approaches may suffer from exploration biases or data incompleteness. (See e.g., T. Rolland et al., “A proteome-scale map of the human interactome network,” Cell 159, 1212 (2014); J. Menche et al., “Uncovering disease-disease relationships through the incomplete interactome,” Science 347, 1257601 (2015), which are incorporated herein by reference for all purposes). Moreover, systematic analyses demonstrated that drugs approved by the U.S. Food and Drug Administration (FDA) may not directly target protein products of the disease-associated genes. (See e.g., M. A. Yildinm et al., “Drug-target network,” Nature biotechnology 25, 1119 (2007); E. Guney et al., “Network-based in silico drug efficacy screening,” Nature communications 7, 1 (2016), which are incorporated herein by reference for all purposes). Network-based target prioritization methods may address these issues by aggregating proteomic, metabolomic, and transcriptomic interactions as well as associations between drugs, diseases, and genes in the form of networks and by deriving the network-based features distinguishing feasible targets in an unbiased and unsupervised manner. (See e.g., S. Zhao et al., “Network-based relating pharmacological and genomic spaces for drug target identification,” PloS one 5, e11764 (2010); Z. Isik et al., “Drug target prioritization by perturbed gene expression and network information,” Scientific reports 5, 1 (2015); T. Katsila et al., “Computational approaches in target identification and drug discovery,” Computational and structural biotechnology journal 14, 177 (2016); E. Guney et al., which are incorporated herein by reference for all purposes). Nonetheless, there is not yet a network-based framework that simultaneously captures the relation between disease formation and successful treatment as a method to identify novel potential targets.
To address at least these issues, disclosed herein are network-based methods for target prioritization for UC that utilizes three network regions (modules) of a Human Interactome (HI)—a network of protein-protein interactions in human cells—referred to as a module triad comprising:
Feasible targets may simultaneously (a) be topologically relevant to the Genotype module, e.g., be in the network vicinity of the genes associated with a particular disease and (b) be functionally similar to the Treatment module, e.g., have a similar transcriptomic downstream effects to that of the Treatment module proteins upon their perturbation. (See e.g., E. Guney et al.). Methods disclosed herein may demonstrate the utility of the proposed framework, using UC as an example, by efficiently recovering known targets approved for UC and distinguishing targets being at different stages of development for UC based on network-derived rankings. The module triad framework may be the first attempt to connect biological mechanisms underlying complex disease development and its treatment dynamics from the network perspective. The module triad framework may be directly extendable to other complex diseases with known gene-disease associations, available gene expression data of patients before and after treatment, and perturbation experiments in appropriate cell lines.
The module triad framework comprises: (1) discovery of the module triad for a given disease; (2) novel target discovery based on the identified module triad, which are illustrated in
For discovery of the module triad, each module may be mapped to the HI using auxiliary disease-specific information. The Genotype module may be constructed by analyzing gene-disease associations databases to locate genes whose mutations may predetermine the formation of the disease phenotype. The Response module comprises the genes that may be significantly down- or up-regulated after treatment in patients that achieved low disease activity. Treatment module construction comprises: (1) using the Library of Integrated Network-Based Cellular Signatures (LINCS) L1000 perturbations database to identify small molecule compounds that result in gene expression profiles similar to that observed for Response module genes after treatment; (2) using the DrugBank and Repurposing Hub databases to extract the set of proteins targeted by these compounds; these proteins are mapped to the HI resulting in the Treatment module. (See e.g., A. Subramanian et al., “A next generation connectivity map: L1000 platform and the first 1,000,000 profiles,” Cell 171, 1437 (2017); C. Knox et al., “DrugBank 3.0: a comprehensive resource for ‘omics’ research on drugs,” Nucleic acids research 39, D1035 (2010); S. M. Corsello et al., “The Drug Repurposing Hub: a next-generation drug library and information resource,” Nature medicine 23, 405 (2017), which are incorporated herein by reference for all purposes).
At least some proteins (nodes) of the HI are ranked based, at least in part, on the constructed Genotype and Treatment modules. For each node, its topological relevance to the Genotype module is assessed based on its proximity which is computed based on the average shortest distance from the node to the Genotype module nodes. (See e.g., E. Guney et al.). Functional similarity of the node to the Treatment module is assessed using selectivity which is computed based on the average diffusion state distance (DSD) of the node to the Treatment module nodes. (See e.g., M. Cao et al., “Going the distance for protein function prediction: a new distance metric for protein interaction networks,” PloS one 8, e76339 (2013), which is incorporated herein by reference for all purposes). For details on computing proximity and selectivity, see
Protein products of genes associated with a disease may not be randomly scattered on the HI but rather form clusters of interconnected nodes reflecting the existence of an underlying biological mechanism behind disease formation. (See e.g., J. Xu et al., Discovering disease-genes by topological features in human protein protein interaction network,” Bioinformatics 22, 2800 (2006); K.-I. Goh et al., “The human disease network,” Proceedings of the National Academy of Sciences 104, 8685 (2007); T. Ideker et al., “Protein networks in disease,” Genome research 18, 644 (2008); A.-L. Barabási et al., “Network medicine: a network-based approach to human disease,” Nature reviews genetics 12, 56 (2011), which are incorporated herein by reference for all purposes). Studying network properties of these interconnected clusters has advanced understanding of disease molecular mechanisms, target discovery, and drug repurposing. (See e.g., J. Menche et al.; A. Sharma et al., “A disease module in the interactome explains disease heterogeneity, drug response and captures novel pathways and genes in asthma,” Human molecular genetics 24, 3005 (2015); E. Guney et al.; F. Cheng et al., “Network-based approach to prediction and population-based validation of in silico drug repurposing,” Nature communications 9, 1 (2018), which are incorporated herein by reference for all purposes).
To include the notion of UC genetic associations in the module triad framework, GWAS Catalog, ClinVar, or MalaCards databases may be used to extract genes reported to have associations with UC (see Methods described elsewhere herein). (See e.g., A. Buniello et al., “The NHGRI-EBI GWAS Catalog of published genome-wide association studies, targeted arrays and summary statistics 2019,” Nucleic acids research 47, D1005 (2019); M. J. Landrum et al., “ClinVar: improving access to variant interpretations and supporting evidence,” Nucleic acids research 46, D1062 (2018); N. Rappaport et al., “MalaCards: an integrated compendium for diseases and their annotation”, Database 2013 (2013), which are incorporated herein by reference for all purposes). A total of 194 genes were reported in at least one of the three databases as being associated with UC, and 174 of them (89.7%) are mapped to their corresponding protein products in the HI. The protein products are not randomly scattered on the network; 64.9% (113/174) of proteins are interconnected, forming a largest connected component (LCC) that is significantly larger than expected at random (e.g., Z-score=4.82, p<10−4). Methods described herein define this LCC as the Genotype module representing genetic predispositions to UC. A feasible target may be located in the topological vicinity of the Genotype module. (See e.g., E. Guney et al.).
Besides being topologically close to the genes leading to predisposition to UC, a feasible target may also be functionally relevant to the treatment of UC. For example, UC treatment dynamics may be reflected at the transcriptomic level, and perturbing a feasible target may result in transcriptional changes similar to that observed upon successful UC treatment.
UC treatment may be reflected at the transcriptomic level in gene expression data of normal tissue controls and patients with active UC undergoing treatment with TNFi drugs, either infliximab or golimumab, from several studies. (See e.g., I. Arijs et al., “Mucosal gene expression of antimicrobial peptides in inflammatory bowel disease before and after first infliximab treatment,”PloS one 4, e7984 (2009); G. Toedter et al., “Gene expression profiling and response signatures associated with differential responses to infliximab treatment in ulcerative colitis,” Official journal of the American College of Gastroenterology—ACG 106, 1272 (2011); S. Pavlidis et al., “I MDS: an inflammatory bowel disease molecular activity score to classify patients with differing disease-driving pathways and therapeutic response to anti-TNF treatment,” PLoS Computational Biology 15, e1006951 (2019); N. Planell et al, “Transcriptional analysis of the intestinal mucosa of patients with ulcerative colitis in remission reveals lasting epithelial cell alterations,” Gut 62, 967 (2013); T. Montero-Melendez et al., “Identification of novel predictor classifiers for inflammatory bowel disease by gene expression profiling,” PloS one 8, e76235 (2013); J. T. Bjerrum et al., “Transcriptional analysis of left-sided colitis, pancolitis, and ulcerative colitis-associated dysplasia,” Inflammatory bowel diseases 20, 2340 (2014); S. E. Telesco, et al., “Gene expression signature for prediction of golimumab response in a phase 2a open-label trial of patients with ulcerative colitis,” Gastroenterology 155, 1008 (2018), which are incorporated herein by reference for all purposes). Table 4 summarizes TNFi treatment studies used to identify a molecular signature of UC patient response.
A set of 545 genes may be identified that are differentially expressed between patients with active UC and normal controls. These genes may be used as features for Uniform Manifold Approximation and Projection (UMAP) embedding of the gene expression profiles of normal controls and UC patients before and after treatment, split into two groups: patients who achieved low disease activity after treatment (responders) and those who did not (non-responders). (See
From UMAP embedding, apparent distinction may not be observed between the pre-treatment gene expression profiles of responders and non-responders to infliximab or golimumab. Additionally, differentially expressed genes may not be found between the pre-treatment gene expression profiles of responders and non-responders. (See “differential gene expression analysis of responders and nonresponders to TNFi therapy,” described elsewhere herein). Conversely, the post-treatment gene expression profiles of responders are clustered closely with those of normal controls, whereas post-treatment profiles of non-responders to infliximab or golimumab are clustered separately from those of normal controls, indicating that gene expression profiles with high similarity to those of normal controls may be reflective of successful UC treatment. Motivated by these observations, we define “molecular response” to UC treatment as reversal of the gene expression profile of UC patients upon treatment to resemble the gene expression profiles of normal controls.
To further understand what transcriptional changes may cause responders' gene expression profile to become more similar to those of normal controls, differential expression analysis of pre- and post-treatment gene expression profiles of responders were performed. A small fraction of genes dysregulated in responders before treatment with respect to normal controls exhibits significant changes in expression after treatment (See “differential gene expression analysis of responders and nonresponders to TNFi therapy,” described elsewhere herein). Expression of these genes may be reverted in responders upon treatment e.g., genes down-regulated in responders before treatment with respect to normal controls may become up-regulated after treatment and vice versa. Yet, these transcriptional changes may be sufficient to make the gene expression profiles of responders and normal controls similar based on the profile embeddings shown in
Genes belonging to the RBA set may be related to each other via one or multiple biological pathways, proper functioning of which may be restored by inhibition of TNF-α, and therefore may be located close to each other on the HI. To test this, TNFi RBA genes may be mapped on the HI to construct a subnetwork comprised of the nodes corresponding to the RBA genes. The RBA set forms a significant LCC on the HI (91 out of 271 nodes, 34%) as compare d to a randomly selected set of nodes with preserved degree sequence (Z-score=9.24, p<10−4). This refined set of genes in the RBA LCC is defined as the Response module, e.g., the region of the HI transcriptionally altered when a UC patient achieves low disease activity in response to therapeutic intervention.
Successful treatment of UC may require reverting the expression profile of the Response module nodes by studying the gene expression profiles of UC patients undergoing TNFi therapies. Inhibition of TNF-α may not be the only way to achieve predetermined transcriptomic effects in the Response module genes, and perturbation of other proteins may achieve similar downstream effects.
Alternative perturbations that are experimentally validated may be analyzed to result in a molecular response similar to the one observed upon successful TNFi therapy. Differential gene expression effects (signatures) may result from perturbation of human cell lines with small molecule compounds obtained from the LINCS L1000 database. (See e.g., A. Subramanian et al., “A next generation connectivity map: L1000 platform and the first 1,000,000 profiles,” Cell 171, 1437 (2017), which is incorporated herein by reference for all purposes). Perturbation signatures may be derived from LINCS L1000 Level 5 data containing gene-wise Z-scores that indicate the magnitude and direction of change in gene expression for 14,513 compound experiments in the HT29 cell line (e.g., human colorectal adenocarcinoma cell line). Perturbation experiments in the HT29 cell line may be considered because of its relevance to UC-affected tissue (colon) and relatively wide coverage of small molecule compounds.
To find the compounds and corresponding target proteins that revert expression of the Response module genes, the LINCS L1000 experiments may be assessed by computing the Weighted Connectivity Score (WTCS) with respect to the up- and down-regulated genes in the Response module using gene-wise perturbation Z-scores for each HT29 cell line experiment. (See e.g., A. Subramanian et al., “A next generation connectivity map: L1000 platform and the first 1,000,000 profiles,” Cell 171, 1437 (2017), which is incorporated herein by reference for all purposes). To assess statistical significance of the WTCS for a given experiment, a randomization procedure may be employed assigning a pair of p-values, pup and pdown, associated with the enrichment scores of the up- and downregulated genes. (See Methods described elsewhere herein). Compound experiments that have pup≥0.05 and pdown≥0.05, and WTCS≥0 are excluded. This filtering ensures consideration of compounds that have a positive and significant therapeutic effect in terms of reverting the expression of Response module genes.
Of 14,513 compound experiments conducted in the HT29 cell line, 68 experiments have a statistically significant WTCS, ranging from −0.642 to −0.480. 69 proteins appear as a target for at least one of the 25 unique compounds evaluated in these 68 experiments, according to DrugBank™ and Repurposing Hub™ databases. Two proteins may not be mapped to the HI (e.g., they have no known protein interaction partners), and 43 out of 67 remaining proteins (64%) form a LCC of significant size (Z-score=3.39, p<10−4). This LCC is called the Treatment module.
One of the targets belonging to the Treatment module is TNF-α. Moreover, by construction, targeting proteins belonging to the Treatment module may result in transcriptional changes within the Response module similar to those observed upon successful TNFi therapy. Hence, proteins belonging to the Treatment module may offer intervention opportunities for treating UC patients.
Besides potential intervention opportunities suggested directly from the Treatment module nodes, the Genotype and Treatment modules can be used to prioritize, in an unsupervised fashion, all nodes in the HI for their potential as a UC treatment target. A feasible target may simultaneously satisfy the following network properties. A feasible target may be topologically close to HI nodes associated with genetic predisposition to UC (Genotype module). Target prioritization based on the network proximity of nodes to disease modules is predictive of therapeutic effects of drugs with known targets across multiple diseases. (See e.g., E. Guney et al.). Therefore, to quantify topological relevance of a given HI node to the UC Genotype module, its proximity to the Genotype module may be calculated based on the average network shortest path of the node to the Genotype module (see Methods described elsewhere herein).
Also, targeting a feasible target may cause transcriptional changes similar to those observed upon successful UC treatment. The Treatment module defines a network region consisting of nodes that, upon perturbation, may result in desirable transcriptional changes in Response module genes. Therefore, proteins that are functionally similar to Treatment module proteins may also be promising targets. Yet, to find such targets, a methodology may quantify downstream transcriptional effect similarities of HI nodes based on network structure. For this, diffusion state distance (DSD), a metric based on network random walks designed to capture propagation-based topological similarities between each pair of nodes in the network, may be used because of its superior performance in predicting protein functional annotations. (See e.g., M. Cao et al.).
To evaluate whether DSD reflects similarities in downstream transcriptional effects between different proteins, the recovery of approved drugs for four complex diseases may be analyzed (e.g., Alzheimer's disease, ulcerative colitis, rheumatoid arthritis, and multiple sclerosis) based on DSD between the HI nodes. (See Methods, described elsewhere herein). The targets of each approved drug may result in similar therapeutic effects of treating a given disease. Thus, efficiently recovering approved targets may be possible by knowing one drug target and its DSD to other HI nodes. Such target recovery may be performed separately for each approved target and complex disease to derive receiver operator characteristic (ROC) curves as shown in
Yet, a node that has low DSD to the Treatment module may be equally close to other randomly chosen modules of equal size in the HI. To account for this, functional similarity between HI nodes and the Treatment module may be quantified using selectivity e.g., a network-based measure based on the DSD that considers statistical significance of the DSD between a node and a given network module. (See Methods described elsewhere herein).
Finally, all HI nodes may be ranked based on their proximity to the Genotype module and selectivity to the Treatment module, and the rank product may be used to determine the final combined ranking of the nodes. (See Methods described elsewhere herein). (See e.g., R. Breitling et al.).
To test if the proposed target ranking yields meaningful results, drug targets approved for UC treatment were obtained from the PharmaIntelligence™ Citeline database. (See Methods described elsewhere herein). The resulting list comprises 23 targets mapped on the HI. The approved targets are simultaneously highly proximal to the Genotype module and selective to the Treatment module compared to the rest of HI nodes as shown in
Finally, drugs that are under consideration as a UC treatment (e.g., being tested in clinical and preclinical trials) may target nodes that have a lower combined ranking based on the proximity and selectivity when compared to the targets that are already launched for UC. This is because launched targets have already been assessed through clinical stages for their ability to ameliorate disease activity in UC patients, while targets that are not yet launched may not necessarily be efficacious for treatment of UC. Distribution of the combined ranks may be compared for the targets of drugs that are launched, in clinical trials (Phase I, II, III), or preclinical studies as shown in
Described herein are a network-based framework and methods for prioritizing protein targets as novel therapies for complex diseases using UC as an example disease. The module triad framework is the first attempt at capturing both formation and successful treatment of disease at the network level assuming that the mechanism behind complex disease formation and treatment can be captured by the interplay between the three network modules of genetic predisposition, transcriptional changes, and protein targets of drugs on the HI. In methods described herein, formation of the disease phenotype is predetermined by the genetic mutations in a collection of genes that are localized in the HI region called the Genotype module. These genetic alterations within the Genotype module manifested in gene expression changes in patients with active UC. By tracking the genes whose expression levels changed significantly in the patients that achieved low disease activity upon TNFi therapy, a collection of genes may be derived that may be transcriptionally altered in order to achieve a positive response to the treatment. These genes occupy a localized region of the HI termed the Response module.
Proteins targeting may be identified which results in a similar transcriptional perturbation profile as achieved upon successful TNFi therapy. Methods described herein may do so by scanning the experimental data of the small molecule compounds perturbing human cells and matching the response profiles after compound perturbation with the profile achieved upon successful treatment. The collection of compound targets that achieve the predetermined downstream change of gene expression also occupies a localized region in the HI and is called the Treatment module. While the identified compounds matching the predetermined transcriptomic downstream effect may seem different, as illustrated in Table 6 (which indicates drugs and their known mechanisms of action mapped to the protein targets belonging to the Treatment module), their targets belong to a localized region of the HI, reflecting common underlying biology behind treatment of UC, and suggesting that other protein targets that are functionally similar to the Treatment module nodes are promising targets for UC treatment. By ranking the HI nodes based on their proximity to the Genotype module and selectivity to the Treatment module, methods disclosed herein may prioritize the HI proteins that are simultaneously topologically relevant to the genes associated with formation of UC phenotype and functionally similar to proteins that have desirable treatment downstream effect when being targeted.
Proximity used for quantifying topological relevance of targets to Genotype module was shown to offer an unbiased measure of therapeutic effects across various drugs and diseases and for distinguishing palliative treatments from effective treatments. (See e.g., E. Guney et al.). Drugs whose targets are proximal to genes associated with a disease are more likely to be effective than more distant drugs. (See e.g., E. Guney et al.). Methods described herein used DSD as a proxy for measuring similarity between downstream effects resulting from perturbing a given pair of nodes in the HI. DSD between a pair of nodes is based on similarity between random walks starting from these nodes. Visiting frequencies of random walkers per node were successfully used to assess perturbation patterns resulting from elementary mutations in genes related to cancer (e.g., single-nucleotide variations and insertion/deletion mutations). (See e.g., M. D. Leiserson et al., “Pan-cancer network analysis identifies combinations of rare somatic mutations across pathways and protein complexes,” Nature genetics 47, 106 (2015), which is incorporated herein by reference for all purposes). Visiting frequencies of the random walk starting from a given node may correspond to the amount of perturbation this node imposes on the rest of the network, and the downstream perturbation effect is reflected in the vector of visiting frequencies of the random walk starting at a given node. Since DSD measures the distance between the vectors of random walks' visiting frequencies (see Methods described elsewhere herein), a pair of nodes with small DSD corresponds to the nodes with similar downstream perturbation effects. DSD is indeed reflective of similarities between therapeutic effects of different targets by recovering known approved targets for 4 complex diseases, including UC, based on the DSD.
The module triad framework and methods disclosed herein may utilize knowledge about the treatment dynamics of patients with active UC that achieved low disease activity upon TNFi therapy. However, patients that do not demonstrate sufficient response to TNFi therapy represent a large fraction of diseased population and may potentially suffer from UC subtype that is different in its underlying biology or disrupts normal cellular processes more severely. (See “pathway enrichment analysis of differentially expressed genes in responders and non-responders to TNFi therapy,” described elsewhere herein). (See e.g., P. Rutgeerts et al.). While novel targets identified using methods described herein may help to find therapies suitable for TNFi non-responders, research of exact biology behind insufficient response to TNFi therapies may still be required.
The module triad framework and methods described herein utilizing patients genomic and transcriptomic data may offer a holistic network-based view on the formation and treatment dynamics of complex diseases and may provide an unbiased approach to novel target identification. Methods disclosed herein can be generalized to any complex disease with available gene-disease associations data, transcriptomic data of patients before and after treatment, and perturbation experiments in an appropriate cell line. Besides target prioritization, methods disclosed herein can suggest repurposing opportunities based on the targets belonging to the Treatment module. Module triad methods may be enhanced by considering available perturbation experiments such as single-gene overexpression and knockdown, including information about agonist or antagonist action of drugs on their targets, or by further refining the list of prioritized targets considering their toxicity and druggability.
Human interactome. The HI map of experimentally derived protein-protein interactions is assembled from public databases. (See e.g., T. Mellors et al., “Clinical validation of a blood-based predictive test for stratification of response to tumor necrosis factor inhibitor therapies in rheumatoid arthritis patients,” Network and Systems Medicine 3, 91 (2020), which is incorporated herein by reference for all purposes). The HI used herein is assembled using e.g., database versions as of March 2021.
Construction of the UC Genotype module. Genes associated with UC are identified as indicated by the (1) GWAS catalog; (2) ClinVar database, specifically, genes that are indicated as “pathogenic”, “likely pathogenic”, and with “conflicting interpretations” of pathogenicity; and (3) MalaCards database. (See e.g., A. Buniello et al.; M. J. Landrum et al.; N. Rappaport et al.) The genes are collected from e.g., the databases as of September 2021. All the genes that are mentioned in at least one of the three databases may be retained, and the genes that are not part of the HI network may be filtered out. The remaining genes may be used to construct a subnetwork and to extract the largest connected component (LCC) of it.
Significance of the LCC size may be assessed by randomly sampling subnetworks with the degree sequence as in the original subnetwork. By repeatedly sampling 10,000 subnetworks, an empirical distribution may be found of the LCC size of randomly sampled subnetworks with its mean μLCC and standard deviation σLCC. Methods disclosed herein define the LCC Z-score as:
where SLCC is the LCC size of the original subnetwork. Method disclosed herein also define the empirical p-value for the observed SLCC as the fraction of the randomly sampled subnetworks that had their LCC size exceeding SLCC.
Gene expression data processing for active UC cases and normal controls. Tissue mucosal samples were collected from normal controls and patients with moderately to severely active UC from Gene Expression Omnibus (GEO), as shown in Table 4. (See e.g., T. Barrett et al., “NCBI GEO: archive for functional genomics data sets—update,” Nucleic acids research 41, D991 (2012), which is incorporated herein by reference for all purposes). Three studies reported patient response statuses after treatment, where responses are determined by endoscopic and histologic findings or Mayo scores. See Table 7 for details on the response definition, for example, definitions of TNFi response across cohorts with specified UC patients' response labels. Methods disclosed herein obtained normalized data within each study from e.g., GeneVestigator® database. (See e.g., T. Hruz et al., “Genevestigator v3: a reference expression database for the meta-analysis of transcriptomes,” Advances in bioinformatics 2008 (2008), which is incorporated herein by reference for all purposes).
Methods disclosed herein may integrate the expression data from 6 infliximab studies together. Batch effects among different studies are corrected using ComBat© statistical methods. (See e.g., J. T. Leek et al., “sva: Surrogate Variable Analysis R package version 3.10.0,” DOI 10, B9 (2014), which is incorporated herein by reference for all purposes). Some studies include baseline samples and samples collected at follow-up visits. To avoid underestimating variance introduced by analysis of longitudinal correlated samples, methods disclosed herein may apply ComBat® statistical methods to baseline samples to derive correction factors for individual studies, treating response and health status as covariates. The correction factors are implemented on baseline and follow-up visit samples.
Clustering and differential gene expression analysis. To reduce dimensionality of the gene expression data, methods disclosed herein may select a subset of gene features that are significantly differentially expressed between normal controls and UC active samples. Genes with fold change (FC) of FC≥2.5 and adjusted p-value (Benjamini-Hochberg correction) of padj.<0.05 may be extracted. (See e.g., Y. Benjamini et al., “Controlling the false discovery rate: a practical and powerful approach to multiple testing,” Journal of the Royal statistical society series B (Methodological) 57, 289 (1995), which is incorporated herein by reference for all purposes). For clustering analysis, methods disclosed herein may embed gene expression vectors of the identified differentially expressed genes into 8-dimensional space using UMAP. (See e.g., L. McInnes et al.).
When comparing the pre- and post-treatment gene expression profiles of the active UC patients, FC>1.8 and padj.<0.05 thresholds may be used to identify differentially expressed genes. The differentially expressed genes with negative log-fold change are considered significantly down-regulated while genes with positive log-fold change are considered significantly up-regulated. For more details on the paired analysis of differentially expressed genes, see “differential gene expression analysis of responders and nonresponders to TNFi therapy,” described elsewhere herein.
Construction of the UC Response module. To identify genes indicative of response to TNFi therapy, methods disclosed herein may extract the genes that are significantly differentially expressed in responders to infliximab and golimumab comparing their gene expression profiles before and after treatment as described above. The two RBA gene sets may be obtained from infliximab- and golimumab-based studies (see “differential gene expression analysis of responders and nonresponders to TNFi therapy,” described elsewhere herein), and a union of these two sets may be used to account for possible drug-specific gene expression changes. A subnetwork based on the obtained merged RBA gene set and the HI may be constructed. The LCC of the resulting subnetwork may be identified as the UC Response module and significance of its size analogously to the Genotype module may be assessed.
Analysis of LINCS L1000 perturbation profiles. Methods disclosed herein may assess the concordance between the differential gene expression profile upon perturbation of HT29 cells using various compounds and the genes belonging to the Response module split into up- and down-regulated subsets using Weighted Connectivity Score (WTCS). (See e.g., A. Subramanian et al., “A next generation connectivity map: L1000 platform and the first 1,000,000 profiles,” Cell 171, 1437 (2017), which is incorporated herein by reference for all purposes). WTCS measures the enrichment score, ES, of ranked lists of genes with a given pair of up- and down-regulated gene sets, that are referred to here as up- and down-query. (See e.g., A. Subramanian et al., “Gene set enrichment analysis: a knowledge-based approach for interpreting genome-wide expression profiles,” Proceedings of the National Academy of Sciences 102, 15545 (2005), which is incorporated herein by reference for all purposes, which is incorporated herein by reference for all purposes). WTCS combines the ES for up-query (ESup) and down-query (ESdown) into a single score. A positive WTCS indicates that a perturbation resulted in a gene expression change that aligns with the Response module query set, e.g., up-query genes are also mainly up-regulated in a given perturbation while down-query genes are mainly down-regulated in a given perturbation. Conversely, a negative WTCS indicated that down-query genes are up-regulated in a given experiment while up-query genes are down-regulated. As we are interested in reverting expression patterns of the Response module genes, we look for experiments with negative WTCS. Below is the brief outline of the procedure used to compute this score and to assess its statistical significance.
LINCS L1000 Level 5 data stores differential gene expression profiles in terms of gene-specific Z-scores indicating changes in expression levels of genes with respect to controls. Large positive Z-score indicates that a gene is significantly up-regulated upon perturbation, while large negative Z-score indicates that a gene is significantly down-regulated upon perturbation. Genes for which differential expression patterns are inferred with high fidelity belong to the set of Best INferred Genes (BING) and are used for WTCS computation. (See e.g., A. Subramanian et al., “A next generation connectivity map: L1000 platform and the first 1,000,000 profiles,” Cell 171, 1437 (2017), which is incorporated herein by reference for all purposes). Up-regulated and down-regulated genes observed in the Response module that are also part of the BING set are denoted here as sup and sdown, respectively. For each sets, methods disclosed herein may calculate enrichment scores (ESup and ESdown), and WTCS is a combination of these two scores:
To assess the significance of the enrichment scores, genes sets of sizes |sup|, |sdown| may be sampled uniformly from BING genes. By repeating the sampling procedure 1,000 times, empirical distributions of up- and down-enrichment scores from random samples, ρup (ES), ρdown (ES), may be obtained. The obtained distributions may be compared to the observed ESup and ESdown: if the observed ESup is positive, the fraction of random samples which has greater or equal enrichment scores is selected as the p-value pup, and if it is negative, the fraction of random samples which has smaller or equal enrichment scores is selected as the p-value pup. The pdown is computed in a similar fashion. WTCS, pup, and pdown may be obtained for each perturbation experiment and use them for filtering the relevant perturbations.
Construction of UC Treatment module. Using LINCS L1000 data, methods disclosed herein may identify compounds that are able to revert the expression patterns observed in the Response module nodes. Relevant experiments may be extracted using WTCS<0 and pup<0.05, pdown<0.05 filters described above. The protein targets of the compounds remained after the filtering are identified using DrugBank and Repurposing Hub databases. We then map the resulting set of protein targets on the HI, and construct a subnetwork based on it analogously to the construction of the Response and Genotype modules. Treatment module is the LCC of this subnetwork.
Diffusion state distance. Diffusion state distance (DSD) is a metric defined on network nodes originally designed to predict proteins' functions in protein interaction networks. (See e.g., M. Cao et al.) DSD captures similarities between network's final states when random walkers start from two different nodes. To define the DSD, we first define He(vi, vj)—an expected number of times a random walk (RW) starting at node v, and proceeding for k operations may end up at node vj. Next, for node vi, we define a vector
He(vi)={He(vi,v1), . . . ,He(vi,vn)}.
Then the DSD between nodes vi and vj is defined as
DSD(vi,vj)=∥He(vi)−He(vj)∥1.
where ∥ . . . ∥1 denotes the L1 norm. For any fixed k, DSD is a metric and it converges as k→∞. (See e.g., M. Cao et al.).
DSD as a measure of therapeutic similarity between targeted proteins. To quantify relevance of DSD as a measure of therapeutic effect similarity between proteins, a set of complex diseases and their approved targets may be analyzed through: for each of the known approved targets for a given disease, compute DSDs between that target and the rest of the nodes in the HI; rank the rest of the nodes based on the DSD to a known target, and based on that ranking, construct a receiver operator characteristic (ROC) curve corresponding to the recovery of the rest of the approved targets for a given disease. By iterating over all known approved targets, a set of individual ROC curves is obtained for each of complex diseases. Interpolation may be used to average the individual curves and to obtain the mean ROC curve, and compute the area under it, quantifying the likelihood of finding approved targets given knowledge about a single approved target and its DSD to the rest of the network nodes.
Proximity to UC Genotype module. Computing proximity of a node to the Genotype module comprises. computing the average shortest path length
Selectivity to UC Treatment module. Computing selectivity of a node to the Treatment module is similar to computation of proximity comprising: computing the average DSD (DSD) of a node with respect to the nodes of the Treatment module; assessing statistical significance of the observed DSD by sampling 500 randomized network modules of the same size as the Treatment module, analogously to the proximity calculation. However, instead of the average shortest path distance, we compute the average DSD of the node to each randomized module and construct an empirical distribution of the average DSDs to the randomized modules, with μs being the mean and σs being the standard deviation of this distribution. We define selectivity as:
Network module randomization. Both proximity and selectivity computations may require sampling of randomized modules on the HI. As by construction both Genotype and Treatment modules are connected subnetworks, sampling connected subnetworks uniformly from the fixed HI network may avoid any possible biases of the average shortest path length or DSD with respect to the subnetwork connectedness. Neighbor Reservoir Sampling (NRS) algorithm may be used to sample connected fixed-size subnetworks uniformly. (See e.g., X. Lu et al., “International Conference on Scientific and Statistical Database Management,” Springer, (2012) pp. 195-212, which is incorporated herein by reference for all purposes).
Node ranking based on proximity and selectivity. Given the Genotype and Treatment modules, we compute proximity and selectivity scores of all nodes in the HI, and derive their corresponding ranks, rp and rs, respectively. To obtain a single combined rank r for each node, we used the rank product defined as:
r=√{square root over (rp·rs)}
Local radiality with respect to the Response module. Local radiality of node i with respect to the Response module may be determined using the following equation:
where RM is the set of the Response module nodes, G is the Human Interactome network, spl(i,g,G) is the function measuring the length of the shortest path from node i to node g.
UC approved targets. For validation of the proposed target prioritization framework, a list of targets that are approved for UC treatment may be compiled by retrieving a list of all drugs with a status of launched or in development for UC using e.g., the PharmaIntelligence™ Citeline database as of February 2022. All drugs that are launched for UC are considered as approved drugs. Additionally, drugs are considered that are being tested for UC in clinical trials (Phase I, II, and III) and preclinical trials to compare their combined rankings to those of the approved drugs. For each drug, extract its known targets from e.g., the PharmaIntelligence™ Citeline database, Repurposing Hub database, and DrugBank database. Since a target may be mapped to several drugs, assign the highest reached status to a target based on the statuses of the drugs it is mapped to. For example, if a target is mapped to the two drugs, one of which is in Phase II clinical trials, and one of which is in preclinical trials, the target is labelled as the clinical trials target. Moreover, to avoid drugs that may have potentially many off targets due to high drug promiscuity, filter out the two drugs (sulfasalazine and mesalazine) that have more than 4 targets as shown in
Differential gene expression analysis of responders and nonresponders to TNFi therapy. To assess if responders and non-responders to TNFi therapies can be stratified based on gene expression profiles before treatment, methods disclosed herein may perform differential gene expression analysis using their full gene expression profiles. Significant differences may not be found at the fold change (FC) of FC=1.8 and adjusted p-value (Benjamini-Hochberg correction) of p<0.05. Therefore, evident differences may not exist between responders' and non-responders' before treatment neither in the UMAP embedding space, nor in the actual full gene expression profile space.
Motivated by the fact that before treatment UC active patients' gene expression profiles are not enough to distinguish responders from non-responders, methods disclosed herein may consider normal tissue controls as a comparison reference to derive more evident difference in the gene expression profiles between responders and non-responders. The following four sets of differentially expressed genes may be constructed, comparing different groups of patients and normal controls (see
Non-responders may not show significant changes in gene expression profiles upon treatment, thus NRBA may not contain any significantly differentially expressed genes. R, NR, and RBA sets are highly concordant and may have significant intersection size both for infliximab and golimumab studies as shown in
Moreover, most RBA genes are differentially expressed in baseline responder samples relative to normal controls, indicating that treatment with a TNFi may result in reversion of the expression of a small subset of R genes. On the contrary, despite the significant fraction of RBA genes contained within the NR set, these genes are not significantly altered in non-responders after treatment with TNFi.
The RBA gene sets are almost exclusively comprised of genes contained within the R and NR sets. Moreover, as suggested by UMAP plots shown in
To have a better understanding of the underlying molecular mechanisms of non-response, methods disclosed herein may perform pathway enrichment analysis on the R and NR sets. For each of the KEGG pathways, the fraction of nodes that are part of the R and NR gene sets may be determined as illustrated in
UC-relevant KEGG pathways are more enriched in NR-exclusive genes than that of responders as shown in
To determine if the gene expression profile of non-responders is more severely dysregulated in comparison to that of responders with respect to various pathways, methods disclosed herein may perform enrichment analysis of signaling pathways from the Kyoto® Encyclopedia of Genes and Genomes (KEGG) database. Pathways that are significantly enriched with nonresponders' differentially expressed genes are selected using the significance threshold of padj.<0.05 (hypergeometric test with Benjamini-Hochberg correction). Each selected pathway, genes that are coming exclusively from the R and NR gene sets are identified. The difference between the number of these R- and NR-exclusive genes are computed to assess its significance using the random permutation of R- and NR-exclusive labels on the remaining genes. Pathways for which there is a significant difference between the number of NR-exclusive and R-exclusive genes are retained (padj.<0.05, random permutation test with Benjamini-Hochberg correction).
It is to be understood that while the disclosure has been described in conjunction with the detailed description thereof, the foregoing description is intended to illustrate and not limit the scope of the claims. Other aspects, advantages, and modifications are within the scope of the claims.
This written description uses examples to disclose the methods and systems, including the best mode, and also to enable any person skilled in the art to practice the present embodiments, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the present embodiments is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they include structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.
This application is a continuation of International Application No. PCT/US2022/034368, filed Jun. 21, 2022, which claims priority to U.S. Provisional Application No. 63/213,428, filed Jun. 22, 2021, and U.S. Provisional Application No. 63/329,008, filed Apr. 8, 2022, each of which is incorporated by reference herein in its entirety.
Number | Date | Country | |
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63329008 | Apr 2022 | US | |
63213428 | Jun 2021 | US |
Number | Date | Country | |
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Parent | PCT/US2022/034368 | Jun 2022 | US |
Child | 18544115 | US |