1 2444 142 EPIGENETIC STATES OF NEPHRON PROGENITORS AND EPITHELIAL DIFFERENTIATION. IN MAMMALS, FORMATION OF NEW NEPHRONS ENDS PERINATALLY DUE TO CONSUMPTION OF MESENCHYMAL PROGENITOR CELLS. PREMATURE DEPLETION OF PROGENITORS DUE TO PREMATURITY OR POSTNATAL LOSS OF NEPHRONS DUE TO INJURY CAUSES CHRONIC KIDNEY DISEASE AND HYPERTENSION. INTENSIVE EFFORTS ARE CURRENTLY INVESTED IN DESIGNING REGENERATIVE STRATEGIES TO FORM NEW NEPHRON PROGENITORS FROM PLURIPOTENT CELLS, WHICH UPON FURTHER DIFFERENTIATION PROVIDE A POTENTIAL SOURCE OF NEW NEPHRONS. TO KNOW IF REPROGRAMED RENAL CELLS CAN MAINTAIN THEIR IDENTITY AND FATE REQUIRES KNOWLEDGE OF THE EPIGENETIC STATES OF NATIVE NEPHRON PROGENITORS AND THEIR PROGENY. IN THIS ARTICLE, WE SUMMARIZE CURRENT KNOWLEDGE AND GAPS IN THE EPIGENOMIC LANDSCAPE OF THE DEVELOPING KIDNEY. WE NOW KNOW THAT PAX2/PTIP/H3K4 METHYLTRANSFERASE ACTIVITY PROVIDES THE INITIAL EPIGENETIC SPECIFICATION SIGNAL TO THE METANEPHRIC MESENCHYME. DURING NEPHROGENESIS, THE CAP MESENCHYME HOUSING NEPHRON PROGENITORS IS ENRICHED IN BIVALENT CHROMATIN MARKS; AS TUBULOGENESIS PROCEEDS, THE TUBULAR EPITHELIUM ACQUIRES H3K79ME2. THE LATTER MARK IS UNIQUELY INDUCED DURING EPITHELIAL DIFFERENTIATION. ANALYSIS OF HISTONE LANDSCAPES IN CLONAL METANEPHRIC MESENCHYME CELL LINES AND IN WILMS TUMOR AND NORMAL FETAL KIDNEY HAS REVEALED THAT PROMOTERS OF POISED NEPHROGENESIS GENES CARRY BIVALENT HISTONE SIGNATURES IN PROGENITORS. DIFFERENTIATION OR STIMULATION OF WNT SIGNALING PROMOTES RESOLUTION OF BIVALENCY; THIS DOES NOT OCCUR IN WILMS TUMOR CELLS CONSISTENT WITH THEIR DEVELOPMENTAL ARREST. THE USE OF SMALL CELL NUMBER CHIP-SEQ SHOULD FACILITATE THE CHARACTERIZATION OF THE CHROMATIN LANDSCAPE OF THE METANEPHRIC MESENCHYME AND VARIOUS NEPHRON COMPARTMENTS DURING NEPHROGENESIS. ONLY THEN WE WILL KNOW IF STEM AND SOMATIC CELL REPROGRAMMING INTO KIDNEY PROGENITORS RECAPITULATES NORMAL DEVELOPMENT. 2015 2 2566 51 EPIGENETICS MECHANISMS IN RENAL DEVELOPMENT. APPRECIATION FOR THE ROLE OF EPIGENETIC MODIFICATIONS IN THE DIAGNOSIS AND TREATMENT OF DISEASES IS FAST GAINING ATTENTION. TREATMENT OF CHRONIC KIDNEY DISEASE STEMMING FROM DIABETES OR HYPERTENSION AS WELL AS WILMS TUMOR WILL ALL PROFIT FROM KNOWLEDGE OF THE CHANGES IN THE EPIGENOMIC LANDSCAPES. TO DO SO, IT IS ESSENTIAL TO CHARACTERIZE THE EPIGENOMIC MODIFIERS AND THEIR MODIFICATIONS UNDER NORMAL PHYSIOLOGICAL CONDITIONS. THE TRANSCRIPTION FACTOR PAX2 WAS IDENTIFIED AS A MAJOR EPIGENETIC PLAYER IN THE EARLY SPECIFICATION OF THE KIDNEY. NOTABLY, THE PROGENITORS OF ALL NEPHRONS THAT RESIDE IN THE CAP MESENCHYME DISPLAY A UNIQUE BIVALENT HISTONE SIGNATURE (EXPRESSING REPRESSIVE EPIGENETIC MARKS ALONGSIDE ACTIVATION MARKS) ON LINEAGE-SPECIFIC GENES. THESE CELLS ARE DEEMED POISED FOR DIFFERENTIATION AND COMMITMENT TO THE NEPHROGENIC LINEAGE. IN RESPONSE TO THE APPROPRIATE INDUCING SIGNAL, THESE GENES LOSE THEIR REPRESSIVE HISTONE MARKS, WHICH ALLOW FOR THEIR EXPRESSION IN NASCENT NEPHRON PRECURSORS. SUCH KNOWLEDGE OF THE EPIGENETIC LANDSCAPE AND THE RESULTANT CELL FATE OR BEHAVIOR IN THE DEVELOPING KIDNEY WILL GREATLY IMPROVE THE OVERALL SUCCESS IN DESIGNING REGENERATIVE STRATEGIES AND TISSUE REPROGRAMMING METHODOLOGIES FROM PLURIPOTENT CELLS. 2016 3 859 35 CHROMATIN DYNAMICS IN KIDNEY DEVELOPMENT AND FUNCTION. EPIGENETIC MECHANISMS ARE FUNDAMENTAL KEY FEATURES OF DEVELOPING CELLS CONNECTING DEVELOPMENTAL REGULATORY FACTORS TO CHROMATIN MODIFICATION. CHANGES IN THE ENVIRONMENT DURING RENAL DEVELOPMENT CAN HAVE LONG-LASTING EFFECTS ON THE PERMANENT TISSUE STRUCTURE AND THE LEVEL OF EXPRESSION OF IMPORTANT FUNCTIONAL GENES. THESE CHANGES ARE BELIEVED TO CONTRIBUTE TO KIDNEY DISEASE OCCURRENCE AND PROGRESSION. ALTHOUGH THE MECHANISMS OF EARLY PATTERNING AND CELL FATE HAVE BEEN WELL DESCRIBED FOR RENAL DEVELOPMENT, LITTLE IS KNOWN ABOUT ASSOCIATED EPIGENETIC MODIFICATIONS AND THEIR IMPACT ON HOW GENES INTERACT TO SPECIFY THE RENAL EPITHELIAL CELLS OF NEPHRONS AND HOW THIS SPECIFICATION IS RELEVANT TO MAINTAINING NORMAL RENAL FUNCTION. A BETTER UNDERSTANDING OF THE RENAL CELL-SPECIFIC EPIGENETIC MODIFICATIONS AND THE INTERACTION OF DIFFERENT CELL TYPES TO FORM THIS HIGHLY COMPLEX ORGAN WILL NOT ONLY HELP TO BETTER UNDERSTAND DEVELOPMENTAL DEFECTS AND EARLY LOSS OF KIDNEY FUNCTION IN CHILDREN, BUT ALSO HELP TO UNDERSTAND AND IMPROVE CHRONIC DISEASE PROGRESSION, CELL REGENERATION AND RENAL AGING. 2014 4 6308 32 THE REGULATION OF APOPTOSIS IN KIDNEY DEVELOPMENT: IMPLICATIONS FOR NEPHRON NUMBER AND PATTERN? APOPTOSIS IS ESSENTIAL TO REMODEL DEVELOPING STRUCTURES AND ELIMINATE SUPERFLUOUS CELLS IN A CONTROLLED MANNER DURING NORMAL DEVELOPMENT, AND CONTINUES TO BE AN IMPORTANT COMPONENT OF TISSUE REMODELING AND REGENERATION DURING AN ORGANISM'S LIFESPAN, OR AS A RESPONSE TO INJURY. THIS MINI REVIEW WILL DISCUSS RECENT STUDIES THAT HAVE PROVIDED INSIGHTS INTO THE ROLES OF APOPTOSIS IN THE DETERMINATION OF NEPHRON NUMBER AND PATTERN, DURING NORMAL AND ABNORMAL KIDNEY DEVELOPMENT. THE REGULATION OF CONGENITAL NEPHRON ENDOWMENT HAS IMPLICATIONS FOR RISK OF CHRONIC KIDNEY DISEASE IN LATER LIFE, WHEREAS ABNORMALITIES IN NEPHRON PATTERN ARE ASSOCIATED WITH CONGENITAL ANOMALIES OF THE KIDNEY AND URINARY TRACT (THE LEADING CAUSE OF RENAL DISEASE IN CHILDREN). TIGHT REGULATION OF APOPTOSIS IS REQUIRED IN NORMAL RENAL MORPHOGENESIS, ALTHOUGH MANY QUESTIONS REMAIN REGARDING THE REGULATION OF APOPTOSIS BY GENETIC, EPIGENETIC, AND ENVIRONMENTAL FACTORS, IN ADDITION TO THE FUNCTIONAL REQUIREMENT OF DIFFERENT COMPONENTS OF THE APOPTOTIC PATHWAY. 2014 5 2592 29 EPIGENETICS OF RENAL DEVELOPMENT AND DISEASE. AN UNDERSTANDING OF EPIGENETICS IS INDISPENSABLE TO OUR UNDERSTANDING OF GENE REGULATION UNDER NORMAL AND PATHOLOGICAL STATES. THIS KNOWLEDGE WILL HELP WITH DESIGNING BETTER THERAPEUTIC APPROACHES IN REGENERATIVE TISSUE MEDICINE. EPIGENETICS ALLOWS US TO PARSE OUT THE MECHANISMS BY WHICH TRANSCRIPTIONAL REGULATORS GAIN ACCESS TO SPECIFIC GENE LOCI THEREBY IMPRINTING EPIGENETIC INFORMATION AFFECTING CHROMATIN FUNCTION. THIS EPIGENETIC MEMORY FORMS THE BASIS OF CELL LINEAGE SPECIFICATION IN MULTICELLULAR ORGANISMS. POST-TRANSLATIONAL MODIFICATIONS TO DNA AND HISTONES IN THE NUCLEOSOME CORE FORM CHARACTERISTIC EPIGENETIC CODES WHICH ARE DISTINCT FOR SELF-RENEWING AND PRIMED PROGENITOR CELL POPULATIONS. STUDIES OF CHROMATIN MODIFIERS AND MODIFICATIONS IN RENAL DEVELOPMENT AND DISEASE HAVE BEEN GAINING MOMENTUM. BOTH CONGENITAL AND ADULT RENAL DISEASES HAVE A GENE-ENVIRONMENT COMPONENT, WHICH INVOLVES ALTERATIONS TO THE EPIGENETIC INFORMATION IMPRINTED DURING DEVELOPMENT. THIS EPIGENETIC MEMORY MUST BE CHARACTERIZED TO ESTABLISH OPTIMAL TREATMENT OF BOTH ACUTE AND CHRONIC RENAL DISEASES. 2016 6 2541 34 EPIGENETICS IN KIDNEY DEVELOPMENT AND RENAL DISEASE. THE STUDY OF EPIGENETICS IS INTIMATELY LINKED AND INSEPARABLE FROM DEVELOPMENTAL BIOLOGY. MANY OF THE GENES THAT IMPRINT EPIGENETIC INFORMATION ON CHROMATIN FUNCTION DURING THE SPECIFICATION OF CELL LINEAGES IN THE DEVELOPING EMBRYO. THESE INCLUDE THE HISTONE METHYLTRANSFERASES AND THEIR COFACTORS OF THE POLYCOMB AND TRITHORAX GENE FAMILIES. HOW HISTONE METHYLATION IS ESTABLISHED AND WHAT REGULATES THE TISSUE AND LOCUS SPECIFICITY OF HISTONE METHYLATION IS AN EMERGING AREA OF RESEARCH. THE EMBRYONIC KIDNEY IS USED AS A MODEL TO UNDERSTAND HOW DNA-BINDING PROTEINS CAN SPECIFY CELL LINEAGES AND HOW SUCH PROTEINS INTERACT DIRECTLY WITH THE HISTONE METHYLATION MACHINERY TO GENERATE A UNIQUE EPIGENOME FOR PARTICULAR TISSUES AND CELL TYPES. IN ADULT TISSUES, HISTONE METHYLATION MARKS MUST BE MAINTAINED FOR NORMAL GENE EXPRESSION PATTERNS. IN CHRONIC AND ACUTE RENAL DISEASE, EPIGENETIC MARKS ARE BEING CHARACTERIZED AND CORRELATED WITH THE ESTABLISHMENT OF METABOLIC MEMORY, IN PART TO EXPLAIN THE PERSISTENCE OF PATHOLOGIES EVEN WHEN OPTIMAL TREATMENT MODALITIES ARE USED. THUS, THE STATE OF THE EPIGENOME IN ADULT CELLS MUST BE CONSIDERED WHEN ATTEMPTING TO ALLEVIATE OR ALTER GENE EXPRESSION PATTERNS IN DISEASE. 2015 7 5798 37 STEM CELLS AND LUNG REGENERATION. THE ABILITY TO REPLACE DEFECTIVE CELLS IN AN AIRWAY WITH CELLS THAT CAN ENGRAFT, INTEGRATE, AND RESTORE A FUNCTIONAL EPITHELIUM COULD POTENTIALLY CURE A NUMBER OF LUNG DISEASES. PROGRESS TOWARD THE DEVELOPMENT OF STRATEGIES TO REGENERATE THE ADULT LUNG BY EITHER IN VIVO OR EX VIVO TARGETING OF ENDOGENOUS STEM CELLS OR PLURIPOTENT STEM CELL DERIVATIVES IS LIMITED BY OUR FUNDAMENTAL LACK OF UNDERSTANDING OF THE MECHANISMS CONTROLLING HUMAN LUNG DEVELOPMENT, THE PRECISE IDENTITY AND FUNCTION OF HUMAN LUNG STEM AND PROGENITOR CELL TYPES, AND THE GENETIC AND EPIGENETIC CONTROL OF HUMAN LUNG FATE. IN THIS REVIEW, WE INTEND TO DISCUSS THE KNOWN STEM/PROGENITOR CELL POPULATIONS, THEIR RELATIVE DIFFERENCES BETWEEN RODENTS AND HUMANS, THEIR ROLES IN CHRONIC LUNG DISEASE, AND THEIR THERAPEUTIC PROSPECTS. ADDITIONALLY, WE HIGHLIGHT THE RECENT BREAKTHROUGHS THAT HAVE INCREASED OUR UNDERSTANDING OF THESE CELL TYPES. THESE ADVANCEMENTS INCLUDE NOVEL LINEAGE-TRACED ANIMAL MODELS AND SINGLE-CELL RNA SEQUENCING OF HUMAN AIRWAY CELLS, WHICH HAVE PROVIDED CRITICAL INFORMATION ON THE STEM CELL SUBTYPES, TRANSITION STATES, IDENTIFYING CELL MARKERS, AND INTRICATE PATHWAYS THAT COMMIT A STEM CELL TO DIFFERENTIATE OR TO MAINTAIN PLASTICITY. AS OUR CAPACITY TO MODEL THE HUMAN LUNG EVOLVES, SO WILL OUR UNDERSTANDING OF LUNG REGENERATION AND OUR ABILITY TO TARGET ENDOGENOUS STEM CELLS AS A THERAPEUTIC APPROACH FOR LUNG DISEASE. 2020 8 6168 21 THE GOOD AND BAD OF BETA-CATENIN IN KIDNEY DEVELOPMENT AND RENAL DYSPLASIA. CONGENITAL RENAL MALFORMATIONS ARE A MAJOR CAUSE OF CHILDHOOD AND ADULT ONSET CHRONIC KIDNEY DISEASE. IDENTIFYING THE ETIOLOGY OF THESE RENAL DEFECTS IS OFTEN CHALLENGING SINCE DISRUPTIONS IN THE PROCESSES THAT DRIVE KIDNEY DEVELOPMENT CAN RESULT FROM DISRUPTIONS IN ENVIRONMENTAL, GENETIC, OR EPIGENETIC CUES. BETA-CATENIN IS AN INTRACELLULAR MOLECULE INVOLVED IN CELL ADHESION, CELL SIGNALING, AND REGULATION OF GENE TRANSCRIPTION. IT PLAYS ESSENTIAL ROLES IN KIDNEY DEVELOPMENT AND IN THE PATHOGENESIS OF RENAL DYSPLASIA. HERE, WE REVIEW THE FUNCTION OF BETA-CATENIN DURING KIDNEY DEVELOPMENT AND IN THE GENESIS OF RENAL DYSPLASIA. 2015 9 3826 35 INVESTIGATION OF EPIGENETICS IN KIDNEY CELL BIOLOGY. EPIGENETICS IS THE STUDY OF HERITABLE CHANGES IN DNA OR ITS ASSOCIATED PROTEINS EXCEPT MUTATIONS IN GENE SEQUENCE. EPIGENETIC REGULATION PLAYS FUNDAMENTAL ROLES IN THE PROCESSES OF KIDNEY CELL BIOLOGY THROUGH THE ACTION OF DNA METHYLATION, CHROMATIN MODIFICATIONS VIA EPIGENETIC REGULATORS AND INTERACTION VIA TRANSCRIPTION FACTORS, AND NONCODING RNA SPECIES. KIDNEY DISEASES, INCLUDING ACUTE KIDNEY INJURY, CHRONIC KIDNEY DISEASE, NEPHRITIC AND NEPHROTIC SYNDROMES, PYELONEPHRITIS AND POLYCYSTIC KIDNEY DISEASES ARE DRIVEN BY ABERRANT ACTIVITY IN NUMEROUS SIGNALING PATHWAYS IN EVEN INDIVIDUAL KIDNEY CELL. EPIGENETIC ALTERATIONS, INCLUDING DNA METHYLATION, HISTONE ACETYLATION AND METHYLATION, NONCODING RNAS, AND PROTEIN POSTTRANSLATIONAL MODIFICATIONS, COULD DISRUPT ESSENTIAL PATHWAYS THAT PROTECT THE RENAL CELLS FROM UNCONTROLLED GROWTH, APOPTOSIS AND ESTABLISHMENT OF OTHER RENAL ASSOCIATED SYNDROMES, WHICH HAVE BEEN RECOGNIZED AS ONE OF THE CRITICAL MECHANISMS FOR REGULATING FUNCTIONAL CHANGES THAT DRIVE AND MAINTAIN THE KIDNEY DISEASE PHENOTYPE. IN THIS CHAPTER, WE BRIEFLY SUMMARIZE THE EPIGENETIC MECHANISMS IN KIDNEY CELL BIOLOGY AND EPIGENETIC BASIS OF KIDNEY DEVELOPMENT, AND INTRODUCE EPIGENETIC TECHNIQUES THAT CAN BE USED IN INVESTIGATING THE MOLECULAR MECHANISM OF KIDNEY CELL BIOLOGY AND KIDNEYS DISEASES, PRIMARILY FOCUSING ON THE INTEGRATION OF DNA METHYLATION AND CHROMATIN IMMUNOPRECIPITATION TECHNOLOGIES INTO KIDNEY DISEASE ASSOCIATED STUDIES. FUTURE STUDIES USING THESE EMERGING TECHNOLOGIES WILL ELUCIDATE HOW ALTERATIONS IN THE RENAL CELL EPIGENOME COOPERATE WITH GENETIC ABERRATIONS FOR KIDNEY DISEASE INITIATION AND PROGRESSION. INCORPORATING EPIGENOMIC TESTING INTO THE CLINICAL RESEARCH IS ESSENTIAL TO FUTURE STUDIES WITH EPIGENETICS BIOMARKERS AND PRECISION MEDICINE USING EMERGING EPIGENETIC THERAPIES. 2019 10 2191 38 EPIGENETIC MEMORY CONTRIBUTING TO THE PATHOGENESIS OF AKI-TO-CKD TRANSITION. EPIGENETIC MEMORY, WHICH REFERS TO THE ABILITY OF CELLS TO RETAIN AND TRANSMIT EPIGENETIC MARKS TO THEIR DAUGHTER CELLS, MAINTAINS UNIQUE GENE EXPRESSION PATTERNS. ESTABLISHING PROGRAMMED EPIGENETIC MEMORY AT EACH STAGE OF DEVELOPMENT IS REQUIRED FOR CELL DIFFERENTIATION. MOREOVER, ACCUMULATING EVIDENCE SHOWS THAT EPIGENETIC MEMORY ACQUIRED IN RESPONSE TO ENVIRONMENTAL STIMULI MAY BE ASSOCIATED WITH DIVERSE DISEASES. IN THE FIELD OF KIDNEY DISEASES, THE "MEMORY" OF ACUTE KIDNEY INJURY (AKI) LEADS TO PROGRESSION TO CHRONIC KIDNEY DISEASE (CKD); EPIDEMIOLOGICAL STUDIES SHOW THAT PATIENTS WHO RECOVER FROM AKI ARE AT HIGH RISK OF DEVELOPING CKD. THE UNDERLYING PATHOLOGICAL PROCESSES INCLUDE NEPHRON LOSS, MALADAPTIVE EPITHELIAL REPAIR, INFLAMMATION, AND ENDOTHELIAL INJURY WITH VASCULAR RAREFACTION. FURTHER, EPIGENETIC ALTERATIONS MAY CONTRIBUTE AS WELL TO THE PATHOPHYSIOLOGY OF THIS AKI-TO-CKD TRANSITION. EPIGENETIC CHANGES INDUCED BY AKI, WHICH CAN BE RECORDED IN CELLS, EXERT LONG-TERM EFFECTS AS EPIGENETIC MEMORY. CONSIDERING THE LATEST FINDINGS ON THE MOLECULAR BASIS OF EPIGENETIC MEMORY AND THE PATHOPHYSIOLOGY OF AKI-TO-CKD TRANSITION, WE PROPOSE HERE THAT EPIGENETIC MEMORY CONTRIBUTING TO AKI-TO-CKD TRANSITION CAN BE CLASSIFIED ACCORDING TO THE PRESENCE OR ABSENCE OF PERSISTENT CHANGES IN THE ASSOCIATED REGULATION OF GENE EXPRESSION, WHICH WE DESIGNATE "DRIVING" MEMORY AND "PRIMING" MEMORY, RESPECTIVELY. "DRIVING" MEMORY, WHICH PERSISTENTLY ALTERS THE REGULATION OF GENE EXPRESSION, MAY CONTRIBUTE TO DISEASE PROGRESSION BY ACTIVATING FIBROGENIC GENES OR INHIBITING RENOPROTECTIVE GENES. THIS PROCESS MAY BE INVOLVED IN GENERATING THE PROINFLAMMATORY AND PROFIBROTIC PHENOTYPES OF MALADAPTIVELY REPAIRED TUBULAR CELLS AFTER KIDNEY INJURY. "PRIMING" MEMORY IS STORED IN SEEMINGLY SUCCESSFULLY REPAIRED TUBULAR CELLS IN THE ABSENCE OF DETECTABLE PERSISTENT PHENOTYPIC CHANGES, WHICH MAY ENHANCE A SUBSEQUENT TRANSCRIPTIONAL RESPONSE TO THE SECOND STIMULUS. THIS TYPE OF MEMORY MAY CONTRIBUTE TO AKI-TO-CKD TRANSITION THROUGH THE CUMULATIVE EFFECTS OF ENHANCED EXPRESSION OF PROFIBROTIC GENES REQUIRED FOR WOUND REPAIR AFTER RECURRENT AKI. FURTHER UNDERSTANDING OF EPIGENETIC MEMORY WILL IDENTIFY THERAPEUTIC TARGETS OF FUTURE EPIGENETIC INTERVENTION TO PREVENT AKI-TO-CKD TRANSITION. 2022 11 2069 35 EPIGENETIC CONTROL OF SKELETAL MUSCLE REGENERATION: INTEGRATING GENETIC DETERMINANTS AND ENVIRONMENTAL CHANGES. DURING EMBRYONIC DEVELOPMENT, PLURIPOTENT CELLS ARE GENETICALLY COMMITTED TO SPECIFIC LINEAGES BY THE EXPRESSION OF CELL-TYPE-SPECIFIC TRANSCRIPTIONAL ACTIVATORS THAT DIRECT THE FORMATION OF SPECIALIZED TISSUES AND ORGANS IN RESPONSE TO DEVELOPMENTAL CUES. CHROMATIN-MODIFYING PROTEINS ARE EMERGING AS ESSENTIAL COMPONENTS OF THE EPIGENETIC MACHINERY, WHICH ESTABLISHES THE NUCLEAR LANDSCAPE THAT ULTIMATELY DETERMINES THE FINAL IDENTITY AND FUNCTIONAL SPECIALIZATION OF ADULT CELLS. RECENT EVIDENCE HAS REVEALED THAT DISCRETE POPULATIONS OF ADULT CELLS CAN RETAIN THE ABILITY TO ADOPT ALTERNATIVE CELL FATES IN RESPONSE TO ENVIRONMENTAL CUES. THESE CELLS INCLUDE CONVENTIONAL ADULT STEM CELLS AND A STILL POORLY DEFINED COLLECTION OF CELL TYPES ENDOWED WITH FACULTATIVE PHENOTYPE AND FUNCTIONAL PLASTICITY. UNDER PHYSIOLOGICAL CONDITIONS OR ADAPTIVE STATES, THESE CELLS COOPERATE TO SUPPORT TISSUE AND ORGAN HOMEOSTASIS, AND TO PROMOTE GROWTH OR COMPENSATORY REGENERATION. HOWEVER, DURING CHRONIC DISEASES AND AGING THESE CELLS CAN ADOPT A PATHOLOGICAL PHENOTYPE AND MEDIATE MALADAPTIVE RESPONSES, SUCH AS THE FORMATION OF FIBROTIC SCARS AND FAT DEPOSITION THAT PROGRESSIVELY REPLACES STRUCTURAL AND FUNCTIONAL UNITS OF TISSUES AND ORGANS. THE MOLECULAR DETERMINANTS OF THESE PHENOTYPIC TRANSITIONS ARE ONLY EMERGING FROM RECENT STUDIES THAT REVEAL HOW DYNAMIC CHROMATIN STATES CAN GENERATE FLEXIBLE EPIGENETIC LANDSCAPES, WHICH CONFER ON CELLS THE ABILITY TO RETAIN PARTIAL PLURIPOTENCY AND ADAPT TO ENVIRONMENTAL CHANGES. THIS REVIEW SUMMARIZES OUR CURRENT KNOWLEDGE ON THE ROLE OF THE EPIGENETIC MACHINERY AS A 'FILTER' BETWEEN GENETIC COMMITMENT AND ENVIRONMENTAL SIGNALS IN CELL TYPES THAT CAN ALTERNATIVELY PROMOTE SKELETAL MUSCLE REGENERATION OR FIBRO-ADIPOGENIC DEGENERATION. 2013 12 1923 22 ENVIRONMENTAL EPIGENETIC MODIFICATIONS AND REPROGRAMMING-RECALCITRANT GENES. THE TERM "ENVIRONMENTAL EPIGENETIC MODIFICATIONS" REFERS TO ALTERATIONS IN PHENOTYPE TRIGGERED BY ENVIRONMENTAL STIMULI VIA EPIGENETIC MECHANISMS. EPIDEMIOLOGIC AND ANIMAL MODEL STUDIES SHOW THAT A SUBSET OF SUCH ENVIRONMENTAL EPIGENETIC MARKS MAY AFFECT SUSCEPTIBILITY TO CHRONIC DISEASES. A GROWING BODY OF EVIDENCE REGARDING INCOMPLETENESS OF REPROGRAMMING INDICATES THAT THE POTENTIAL RETENTION OF PATHOGENIC ENVIRONMENTAL EPIGENETICS IN HUMAN INDUCED PLURIPOTENT STEM CELLS (IPSCS) SHOULD BE SERIOUSLY CONSIDERED. GIVEN THIS POSSIBILITY, THE OPTIMIZATION OF METHODS FOR THE GENERATION OF HUMAN INDUC PLURIPOTENT STEM CELLS MAY REQUIRE THE IDENTIFICATION OF EPIGENETICALLY APPROPRIATE SOMATIC CELL SOURCES. SIMILARLY, TECHNIQUES FOR CONTROLLING EPIGENETIC MODIFICATION BY ENVIRONMENTAL FACTORS MAY ALSO PLAY A CRITICAL ROLE IN THE DEVELOPMENT OF EPIGENETICALLY STABLE SOURCES OF PLURIPOTENT STEM CELLS. 2010 13 3156 24 GLYCEMIC MEMORIES AND THE EPIGENETIC COMPONENT OF DIABETIC NEPHROPATHY. A STRONG CASE FOR THE DEREGULATION OF EPIGENETIC CHROMATIN MODIFICATIONS IN THE DEVELOPMENT AND PROGRESSION OF VARIOUS CHRONIC COMPLICATIONS OF DIABETES HAS EMERGED FROM RECENT EXPERIMENTAL OBSERVATIONS. CLINICAL TRIALS OF TYPE 1 AND TYPE 2 DIABETES PATIENTS HIGHLIGHT THE IMPORTANCE OF EARLY AND INTENSIVE TREATMENT AND THE PROLONGED DAMAGE OF HYPERGLYCEMIA ON ORGANS SUCH AS THE KIDNEY. THE FUNCTIONAL RELATIONSHIP BETWEEN THE REGULATION OF CHROMATIN ARCHITECTURE AND PERSISTENT GENE EXPRESSION CHANGES CONFERRED BY PRIOR HYPERGLYCEMIA REPRESENTS AN IMPORTANT AVENUE OF INVESTIGATION FOR EXPLAINING DIABETIC NEPHROPATHY. WHILE SEVERAL STUDIES IMPLICATE EPIGENETIC CHANGES AT THE CHROMATIN TEMPLATE IN THE DEREGULATED GENE EXPRESSION ASSOCIATED WITH DIABETIC NEPHROPATHY, THE MOLECULAR DETERMINANTS OF METABOLIC MEMORY IN RENAL CELLS REMAIN POORLY UNDERSTOOD. THERE IS NOW STRONG EVIDENCE FROM EXPERIMENTAL ANIMALS AND CELL CULTURE OF PERSISTENT GLUCOSE-DRIVEN CHANGES IN VASCULAR ENDOTHELIAL GENE EXPRESSION THAT MAY ALSO HAVE RELEVANCE FOR THE MICROVASCULATURE OF THE KIDNEY. EXPLORATION OF EPIGENETIC MECHANISMS UNDERLYING THE HYPERGLYCEMIC CUE MEDIATING PERSISTENT TRANSCRIPTIONAL CHANGES IN RENAL CELLS HOLDS NOVEL THERAPEUTIC POTENTIAL FOR DIABETIC NEPHROPATHY. 2013 14 4882 35 OVERVIEW OF THE CELLULAR AND MOLECULAR BASIS OF KIDNEY FIBROSIS. THE COMMON PATHOGENETIC PATHWAY OF PROGRESSIVE INJURY IN PATIENTS WITH CHRONIC KIDNEY DISEASE (CKD) IS EPITOMIZED AS NORMAL KIDNEY PARENCHYMAL DESTRUCTION DUE TO SCARRING (FIBROSIS). UNDERSTANDING THE FUNDAMENTAL PATHWAYS THAT LEAD TO RENAL FIBROSIS IS ESSENTIAL IN ORDER TO DEVELOP BETTER THERAPEUTIC OPTIONS FOR HUMAN CKD. ALTHOUGH COMPLEX, FOUR CELLULAR RESPONSES ARE PIVOTAL. (1) AN INTERSTITIAL INFLAMMATORY RESPONSE THAT HAS MULTIPLE CONSEQUENCES-SOME HARMFUL AND OTHERS HEALING. (2) THE APPEARANCE OF A UNIQUE INTERSTITIAL CELL POPULATION OF MYOFIBROBLASTS, PRIMARILY DERIVED FROM KIDNEY STROMAL CELLS (FIBROBLASTS AND PERICYTES), THAT ARE THE PRIMARY SOURCE OF THE VARIOUS EXTRACELLULAR MATRIX PROTEINS THAT FORM INTERSTITIAL SCARS. (3) TUBULAR EPITHELIAL CELLS THAT HAVE VARIABLE AND TIME-DEPENDENT ROLES AS EARLY RESPONDERS TO INJURY AND LATER AS VICTIMS OF FIBROSIS DUE TO THE LOSS OF THEIR REGENERATIVE ABILITIES. (4) LOSS OF INTERSTITIAL CAPILLARY INTEGRITY THAT COMPROMISES OXYGEN DELIVERY AND LEADS TO A VICIOUS CASCADE OF HYPOXIA-OXIDANT STRESS THAT ACCENTUATES INJURY AND FIBROSIS. IN THE ABSENCE OF ADEQUATE ANGIOGENIC RESPONSES, A HEALTHY INTERSTITIAL CAPILLARY NETWORK IS NOT MAINTAINED. THE FIBROTIC 'SCAR' THAT TYPIFIES CKD IS AN INTERESTING CONSORTIUM OF MULTIFUNCTIONAL MACROMOLECULES THAT NOT ONLY CHANGE IN COMPOSITION AND STRUCTURE OVER TIME, BUT CAN BE DEGRADED VIA EXTRACELLULAR AND INTRACELLULAR PROTEASES. ALTHOUGH TRANSFORMING GROWTH FACTOR BETA APPEARS TO BE THE PRIMARY DRIVER OF KIDNEY FIBROSIS, A VAST ARRAY OF ADDITIONAL MOLECULES MAY HAVE MODULATING ROLES. THE IMPORTANCE OF GENETIC AND EPIGENETIC FACTORS IS INCREASINGLY APPRECIATED. AN INTRIGUING BUT INCOMPLETELY UNDERSTOOD CARDIORENAL SYNDROME UNDERLIES THE HIGH MORBIDITY AND MORTALITY RATES THAT DEVELOP IN ASSOCIATION WITH PROGRESSIVE KIDNEY FIBROSIS. 2014 15 4389 30 MODELING EPIGENETIC MODIFICATIONS IN RENAL DEVELOPMENT AND DISEASE WITH ORGANOIDS AND GENOME EDITING. UNDERSTANDING EPIGENETIC MECHANISMS IS CRUCIAL TO OUR COMPREHENSION OF GENE REGULATION IN DEVELOPMENT AND DISEASE. IN THE PAST DECADES, DIFFERENT STUDIES HAVE SHOWN THE ROLE OF EPIGENETIC MODIFICATIONS AND MODIFIERS IN RENAL DISEASE, ESPECIALLY DURING ITS PROGRESSION TOWARDS CHRONIC AND END-STAGE RENAL DISEASE. THUS, THE IDENTIFICATION OF GENETIC VARIATION ASSOCIATED WITH CHRONIC KIDNEY DISEASE HAS RESULTED IN BETTER CLINICAL MANAGEMENT OF PATIENTS. DESPITE THE IMPORTANCE OF THESE FINDINGS, THE TRANSLATION OF GENOTYPE-PHENOTYPE DATA INTO GENE-BASED MEDICINE IN CHRONIC KIDNEY DISEASE POPULATIONS STILL LACKS FAITHFUL CELLULAR OR ANIMAL MODELS THAT RECAPITULATE THE KEY ASPECTS OF THE HUMAN KIDNEY. THE LATEST ADVANCES IN THE FIELD OF STEM CELLS HAVE SHOWN THAT IT IS POSSIBLE TO EMULATE KIDNEY DEVELOPMENT AND FUNCTION WITH ORGANOIDS DERIVED FROM HUMAN PLURIPOTENT STEM CELLS. THESE HAVE SUCCESSFULLY RECAPITULATED NOT ONLY KIDNEY DIFFERENTIATION, BUT ALSO THE SPECIFIC PHENOTYPICAL TRAITS RELATED TO KIDNEY FUNCTION. THE COMBINATION OF THIS METHODOLOGY WITH CRISPR/CAS9 GENOME EDITING HAS ALREADY HELPED RESEARCHERS TO MODEL DIFFERENT GENETIC KIDNEY DISORDERS. NOWADAYS, CRISPR/CAS9-BASED APPROACHES ALSO ALLOW EPIGENETIC MODIFICATIONS, AND THUS REPRESENT AN UNPRECEDENTED TOOL FOR THE SCREENING OF GENETIC VARIANTS, EPIGENETIC MODIFICATIONS OR EVEN CHANGES IN CHROMATIN STRUCTURE THAT ARE ALTERED IN RENAL DISEASE. IN THIS REVIEW, WE DISCUSS THESE TECHNICAL ADVANCES IN KIDNEY MODELING, AND OFFER AN OVERVIEW OF THE ROLE OF EPIGENETIC REGULATION IN KIDNEY DEVELOPMENT AND DISEASE. 2018 16 6129 30 THE EPIGENETIC REGULATION OF PODOCYTE FUNCTION IN DIABETES. CHRONIC HYPERGLYCEMIA EARLY IN THE COURSE OF DIABETES CONFERS A SUSTAINED INCREASE IN THE RISK OF COMPLICATIONS DEVELOPMENT. IN RECENT YEARS, EFFORTS TO UNDERSTAND THE MOLECULAR BASIS FOR THIS "METABOLIC MEMORY" HAVE FOCUSED ON EPIGENETIC MECHANISMS AS A MEANS BY WHICH TRANSIENT HIGH GLUCOSE CAN CAUSE PERSISTENT AND PROPAGATED CHANGES IN CELL FUNCTION. FOR INSTANCE, IN VASCULAR ENDOTHELIAL CELLS, SMOOTH MUSCLE CELLS AND PERIPHERAL BLOOD CELLS, TEMPORARY EXPOSURE TO HIGH GLUCOSE CAUSES CHANGES IN EPIGENETIC MARKS THAT PROMOTE A SHIFT TOWARDS A PRO-INFLAMMATORY PHENOTYPE. HOWEVER, THE INFLUENCE OF EPIGENETIC PROCESSES IN COMPLICATIONS DEVELOPMENT EXTENDS BEYOND THEIR CONTRIBUTION TO METABOLIC MEMORY. PODOCYTES, FOR EXAMPLE, ARE TERMINALLY DIFFERENTIATED CELLS OF THE RENAL GLOMERULUS WHOSE INJURY IS A MAJOR CONTRIBUTOR TO THE PATHOGENESIS OF NEPHROPATHY. OVER RECENT MONTHS, SEVERAL REPORTS HAVE EMERGED DESCRIBING THE ESSENTIAL ACTIONS OF HISTONE-MODIFYING ENZYMES AND DNA METHYLATION PATTERNS (THE TWO PRINCIPAL EPIGENETIC MECHANISMS) IN MAINTAINING PODOCYTE INTEGRITY, ESPECIALLY UNDER DIABETIC CONDITIONS. HERE, WE REVIEW THE KNOWN AND POTENTIAL ROLE OF EPIGENETIC PROCESSES WITHIN PODOCYTES, FOCUSING ON THE EVIDENCE LINKING THESE PROCESSES TO OXIDATIVE STRESS, CROSSTALK WITH TUBULE CELLS, AUTOPHAGY AND SLIT-PORE PROTEIN EXPRESSION. WHETHER PODOCYTES THEMSELVES EXHIBIT A METABOLIC MEMORY AWAITS TO BE SEEN. 2015 17 2306 33 EPIGENETIC REGULATION OF CELL-FATE CHANGES THAT DETERMINE ADULT LIVER REGENERATION AFTER INJURY. THE ADULT LIVER HAS EXCELLENT REGENERATIVE POTENTIAL FOLLOWING INJURY. IN CONTRAST TO OTHER ORGANS OF THE BODY THAT HAVE HIGH CELLULAR TURNOVER DURING HOMEOSTASIS (E.G., INTESTINE, STOMACH, AND SKIN), THE ADULT LIVER IS A SLOWLY SELF-RENEWING ORGAN AND DOES NOT CONTAIN A DEFINED STEM-CELL COMPARTMENT THAT MAINTAINS HOMEOSTASIS. HOWEVER, TISSUE DAMAGE INDUCES SIGNIFICANT PROLIFERATION ACROSS THE LIVER AND CAN TRIGGER CELL-FATE CHANGES, SUCH AS TRANS-DIFFERENTIATION AND DE-DIFFERENTIATION INTO LIVER PROGENITORS, WHICH CONTRIBUTE TO EFFICIENT TISSUE REGENERATION AND RESTORATION OF LIVER FUNCTIONS. EPIGENETIC MECHANISMS HAVE BEEN SHOWN TO REGULATE CELL-FATE DECISIONS IN BOTH EMBRYONIC AND ADULT TISSUES IN RESPONSE TO ENVIRONMENTAL CUES. UNDERLYING THEIR RELEVANCE IN LIVER BIOLOGY, EXPRESSION LEVELS AND EPIGENETIC ACTIVITY OF CHROMATIN MODIFIERS ARE OFTEN ALTERED IN CHRONIC LIVER DISEASE AND LIVER CANCER. IN THIS REVIEW, I EXAMINE THE ROLE OF SEVERAL CHROMATIN MODIFIERS IN THE REGULATION OF CELL-FATE CHANGES THAT DETERMINE EFFICIENT ADULT LIVER EPITHELIAL REGENERATION IN RESPONSE TO TISSUE INJURY IN MOUSE MODELS. SPECIFICALLY, I FOCUS ON EPIGENETIC MECHANISMS SUCH AS CHROMATIN REMODELLING, DNA METHYLATION AND HYDROXYMETHYLATION, AND HISTONE METHYLATION AND DEACETYLATION. FINALLY, I ADDRESS HOW ALTERED EPIGENETIC MECHANISMS AND THE INTERPLAY BETWEEN EPIGENETICS AND METABOLISM MAY CONTRIBUTE TO THE INITIATION AND PROGRESSION OF LIVER DISEASE AND CANCER. 2021 18 1604 30 DNA METHYLATION SUSTAINS "INFLAMED" MEMORY OF PERIPHERAL IMMUNE CELLS AGGRAVATING KIDNEY INFLAMMATORY RESPONSE IN CHRONIC KIDNEY DISEASE. THE INCIDENCE OF CHRONIC KIDNEY DISEASE (CKD) HAS RAPIDLY INCREASED IN THE PAST DECADES. A PROGRESSIVE LOSS OF KIDNEY FUNCTION CHARACTERIZES A PART OF CKD EVEN WITH INTENSIVE SUPPORTIVE TREATMENT. IRRESPECTIVE OF ITS ETIOLOGY, CKD PROGRESSION IS GENERALLY ACCOMPANIED WITH THE DEVELOPMENT OF CHRONIC KIDNEY INFLAMMATION THAT IS PATHOLOGICALLY FEATURED BY THE LOW-GRADE BUT CHRONIC ACTIVATION OF RECRUITED IMMUNE CELLS. CUMULATIVE EVIDENCE SUPPORT THAT ABERRANT DNA METHYLATION PATTERN OF DIVERSE PERIPHERAL IMMUNE CELLS, INCLUDING T CELLS AND MONOCYTES, IS CLOSELY ASSOCIATED WITH CKD DEVELOPMENT IN MANY CHRONIC DISEASE SETTINGS. THE CHANGE OF DNA METHYLATION PROFILE CAN SUSTAIN FOR A LONG TIME AND AFFECT THE FUTURE GENES EXPRESSION IN THE CIRCULATING IMMUNE CELLS EVEN AFTER THEY MIGRATE FROM THE CIRCULATION INTO THE INVOLVED KIDNEY. IT IS OF CLINICAL INTEREST TO REVEAL THE UNDERLYING MECHANISM OF HOW ALTERED DNA METHYLATION REGULATES THE INTENSITY AND THE TIME LENGTH OF THE INFLAMMATORY RESPONSE IN THE RECRUITED EFFECTOR CELLS. WE AND OTHERS RECENTLY DEMONSTRATED THAT ALTERED DNA METHYLATION OCCURS IN PERIPHERAL IMMUNE CELLS AND PROFOUNDLY CONTRIBUTES TO CKD DEVELOPMENT IN SYSTEMIC CHRONIC DISEASES, SUCH AS DIABETES AND HYPERTENSION. THIS REVIEW WILL SUMMARIZE THE CURRENT FINDINGS ABOUT THE INFLUENCE OF ABERRANT DNA METHYLATION ON CIRCULATING IMMUNE CELLS AND HOW IT POTENTIALLY DETERMINES THE OUTCOME OF CKD. 2021 19 736 34 CANCER STEM CELLS--NEW APPROACH TO CANCEROGENENSIS AND TREATMENT. RECENTLY, THERE IS AN INCREASING EVIDENCE SUPPORTING THE THEORY OF CANCER STEM CELLS NOT ONLY IN LEUKEMIA BUT ALSO IN SOLID CANCER. TO DATE, THE EXISTENCE OF CANCER STEM CELLS HAS BEEN PROVEN IN ACUTE AND CHRONIC MYELOID LEUKEMIA, IN BREAST CANCER, IN BRAIN TUMORS, IN LUNG CANCER AND GASTROINTESTINAL TUMORS. THIS REVIEW IS FOCUSING ON THE RECENT DISCOVERY OF STEM CELLS IN LEUKEMIA, HUMAN BRAIN TUMORS AND BREAST CANCER. A SMALL POPULATION OF CELLS IN THE TUMOR (LESS THAN 1%) SHOWS THE POTENTIAL TO GIVE RISE TO THE TUMOR AND ITS GROWTH. THESE CELLS HAVE A SUBSTANTIAL CHARACTERISTIC OF STEM CELLS--ABILITY FOR SELF-RENEWAL WITHOUT LOSS OF PROLIFERATION CAPACITY WITH EACH CELL DIVISION. FURTHERMORE THEY ARE IMMORTAL, RATHER RESISTANT TO TREATMENT AND EXPRESS TYPICAL MARKERS OF STEM CELLS. THE ORIGIN OF THESE RESIDENT CANCER STEM CELLS IS NOT CLEAR. WHETHER THE CANCER STEM CELLS ORIGINATE FROM NORMAL STEM CELLS IN CONSEQUENCE OF GENETIC AND EPIGENETIC CHANGES AND/OR REDIFFERENTIATION FROM SOMATIC TUMOR CELLS TO THE STEM-LIKE CELLS REMAINS TO BE INVESTIGATED. WE PROPOSE THE IDEA OF THE RELATION BETWEEN NORMAL TISSUE STEM CELLS AND CANCER STEM CELLS AND THEIR POPULATIONS--PROGENITOR CELLS. BASED ON THIS WE HIGHLIGHT ONE OF THE MAJOR CHARACTERISTIC OF STEM CELL--PLASTICITY, WHICH IS EQUALLY IMPORTANT IN THE PHYSIOLOGICAL REGENERATION PROCESS AS WELL AS CARCINOGENESIS. FURTHERMORE, WE CONSIDER THE MICROENVIRONMENT AS A LIMITING FACTOR FOR TUMOR GENESIS IN AML, BREAST CANCER AND BRAIN TUMORS. THUS THE BIOLOGICAL PROPERTIES OF CANCER STEM CELLS ARE JUST BEGINNING TO BE REVEALED, THE CONTINUATION OF THESE STUDIES SHOULD LEAD TO THE DEVELOPMENT OF CANCER STEM CELLS TARGET THERAPIES FOR CANCER TREATMENT. 2008 20 2542 32 EPIGENETICS IN KIDNEY DISEASES. EPIGENETICS EXAMINES HERITABLE CHANGES IN DNA AND ITS ASSOCIATED PROTEINS EXCEPT MUTATIONS IN GENE SEQUENCE. EPIGENETIC REGULATION PLAYS FUNDAMENTAL ROLES IN KIDNEY CELL BIOLOGY THROUGH THE ACTION OF DNA METHYLATION, CHROMATIN MODIFICATION VIA EPIGENETIC REGULATORS AND NON-CODING RNA SPECIES. KIDNEY DISEASES, INCLUDING ACUTE KIDNEY INJURY, CHRONIC KIDNEY DISEASE, DIABETIC KIDNEY DISEASE AND RENAL FIBROSIS ARE MULTISTEP PROCESSES ASSOCIATED WITH NUMEROUS MOLECULAR ALTERATIONS EVEN IN INDIVIDUAL KIDNEY CELLS. EPIGENETIC ALTERATIONS, INCLUDING ANOMALOUS DNA METHYLATION, ABERRANT HISTONE ALTERATIONS AND CHANGES OF MICRORNA EXPRESSION ALL CONTRIBUTE TO KIDNEY PATHOGENESIS. THESE CHANGES ALTER THE GENOME-WIDE EPIGENETIC SIGNATURES AND DISRUPT ESSENTIAL PATHWAYS THAT PROTECT RENAL CELLS FROM UNCONTROLLED GROWTH, APOPTOSIS AND DEVELOPMENT OF OTHER RENAL ASSOCIATED SYNDROMES. MOLECULAR CHANGES IMPACT CELLULAR FUNCTION WITHIN KIDNEY CELLS AND ITS MICROENVIRONMENT TO DRIVE AND MAINTAIN DISEASE PHENOTYPE. IN THIS CHAPTER, WE BRIEFLY SUMMARIZE EPIGENETIC MECHANISMS IN FOUR KIDNEY DISEASES INCLUDING ACUTE KIDNEY INJURY, CHRONIC KIDNEY DISEASE, DIABETIC KIDNEY DISEASE AND RENAL FIBROSIS. WE PRIMARILY FOCUS ON CURRENT KNOWLEDGE ABOUT THE GENOME-WIDE PROFILING OF DNA METHYLATION AND HISTONE MODIFICATION, AND EPIGENETIC REGULATION ON SPECIFIC GENE(S) IN THE PATHOPHYSIOLOGY OF THESE DISEASES AND THE TRANSLATIONAL POTENTIAL OF IDENTIFYING NEW BIOMARKERS AND TREATMENT FOR PREVENTION AND THERAPY. INCORPORATING EPIGENOMIC TESTING INTO CLINICAL RESEARCH IS ESSENTIAL TO ELUCIDATE NOVEL EPIGENETIC BIOMARKERS AND DEVELOP PRECISION MEDICINE USING EMERGING THERAPIES. 2021