1 3047 110 GENOME-WIDE ANALYSIS OF DNA METHYLATION IN ENDOMETRIOSIS USING ILLUMINA HUMAN METHYLATION 450 K BEADCHIPS. ENDOMETRIOSIS IS A COMMON CHRONIC GYNECOLOGIC DISORDER CHARACTERIZED BY THE PRESENCE AND GROWTH OF ENDOMETRIAL-LIKE TISSUE OUTSIDE OF THE UTERINE CAVITY. ALTHOUGH THE EXACT ETIOLOGY REMAINS UNCLEAR, EPIGENETIC MODIFICATIONS, SUCH AS DNA METHYLATION, ARE THOUGHT TO CONTRIBUTE TO THE PATHOGENESIS OF ENDOMETRIOSIS. HERE, WE USED THE ILLUMINA HUMAN METHYLATION 450 K BEADCHIP ARRAY TO ANALYZE THE GENOME-WIDE DNA METHYLATION PROFILES OF SIX ENDOMETRIOTIC LESIONS AND SIX EUTOPIC ENDOMETRIA FROM PATIENTS WITH OVARIAN ENDOMETRIOSIS AND SIX ENDOMETRIA OF WOMEN WITHOUT ENDOMETRIOSIS. COMPARED WITH THE EUTOPIC ENDOMETRIA OF WOMEN WITH ENDOMETRIOSIS, 12,159 DIFFERENTIALLY METHYLATED CPG SITES AND 375 DIFFERENTIALLY METHYLATED PROMOTER REGIONS WERE IDENTIFIED IN ENDOMETRIOTIC LESIONS. GO ANALYSES SHOWED THAT THESE PUTATIVE DIFFERENTIALLY METHYLATED GENES WERE PRIMARILY ASSOCIATED WITH IMMUNE RESPONSE, INFLAMMATORY RESPONSE, RESPONSE TO STEROID HORMONE STIMULUS, CELL ADHESION, NEGATIVE REGULATION OF APOPTOSIS, AND ACTIVATION OF THE MAPK ACTIVITY. IN ADDITION, THE EXPRESSION LEVELS OF DNMT1, DNMT3A, DNMT3B, AND MBD2 IN ENDOMETRIOTIC LESIONS AND EUTOPIC ENDOMETRIA WERE SIGNIFICANTLY DECREASED COMPARED WITH CONTROL ENDOMETRIA. OUR FINDINGS SUGGEST THAT ABERRANT DNA METHYLATION STATUS IN ENDOMETRIOTIC LESIONS MAY PLAY A SIGNIFICANT ROLE IN THE PATHOGENESIS AND PROGRESSION OF ENDOMETRIOSIS. 2019 2 146 36 ABERRANT ENDOMETRIAL DNA METHYLOME AND ASSOCIATED GENE EXPRESSION IN WOMEN WITH ENDOMETRIOSIS. ENDOMETRIOSIS IS AN ESTROGEN-DEPENDENT, PROGESTERONE-RESISTANT DISORDER LARGELY DERIVED FROM RETROGRADE TRANSPLANTATION OF MENSTRUAL TISSUE/CELLS INTO THE PELVIS, ELICITING AN INFLAMMATORY RESPONSE, PELVIC PAIN, AND INFERTILITY. EUTOPIC ENDOMETRIUM (WITHIN THE UTERUS), GIVING RISE TO PELVIC DISEASE, DISPLAYS CYCLE-DEPENDENT TRANSCRIPTOMIC, PROTEOMIC, AND SIGNALING ABNORMALITIES, AND ALTHOUGH ITS DNA METHYLATION PROFILES DYNAMICALLY CHANGE ACROSS THE CYCLE IN HEALTHY WOMEN, STUDIES IN ENDOMETRIOSIS ARE LIMITED. HEREIN, WE INVESTIGATED THE DNA METHYLOME AND ASSOCIATED GENE EXPRESSION IN THREE PHASES OF THE CYCLE IN EUTOPIC ENDOMETRIUM OF WOMEN WITH SEVERE ENDOMETRIOSIS VERSUS CONTROLS, MATCHED FOR ETHNICITY, MEDICATIONS, SMOKING, AND NO RECENT CONTRACEPTIVE STEROID USE. GENOME-WIDE DNA METHYLATION AND GENE EXPRESSION WERE COASSESSED IN EACH SAMPLE. CYCLE PHASE WAS DETERMINED BY HISTOLOGY, SERUM HORMONE LEVELS, AND UNSUPERVISED PRINCIPAL COMPONENT AND HIERARCHICAL CLUSTER ANALYSES OF MICROARRAY DATA. ALTERED ENDOMETRIAL DNA METHYLATION IN ENDOMETRIOSIS WAS MOST PROMINENT IN THE MIDSECRETORY PHASE (PEAK PROGESTERONE), WITH DISRUPTION OF THE NORMAL PATTERN OF CYCLE-DEPENDENT DNA METHYLATION CHANGES, INCLUDING A BIAS TOWARD METHYLATION OF CPG ISLANDS, SUGGESTING WIDE-RANGE ABNORMALITIES OF THE CHROMATIN REMODELING MACHINERY IN ENDOMETRIOSIS. DNA METHYLATION CHANGES WERE ASSOCIATED WITH ALTERED GENE EXPRESSION RELEVANT TO ENDOMETRIAL FUNCTION/DYSFUNCTION, INCLUDING CELL PROLIFERATION, INFLAMMATION/IMMUNE RESPONSE, ANGIOGENESIS, AND STEROID HORMONE RESPONSE. THE DATA PROVIDE INSIGHT INTO EPIGENETIC REPROGRAMMING AND STEROID HORMONE ACTIONS IN ENDOMETRIUM CONTRIBUTING TO THE PATHOGENESIS AND PATHOPHYSIOLOGY OF ENDOMETRIOSIS. 2016 3 3061 45 GENOME-WIDE DNA METHYLATION ANALYSIS PREDICTS AN EPIGENETIC SWITCH FOR GATA FACTOR EXPRESSION IN ENDOMETRIOSIS. ENDOMETRIOSIS IS A GYNECOLOGICAL DISEASE DEFINED BY THE EXTRAUTERINE GROWTH OF ENDOMETRIAL-LIKE CELLS THAT CAUSE CHRONIC PAIN AND INFERTILITY. THE DISEASE IS LIMITED TO PRIMATES THAT EXHIBIT SPONTANEOUS DECIDUALIZATION, AND DISEASED CELLS ARE CHARACTERIZED BY SIGNIFICANT DEFECTS IN THE STEROID-DEPENDENT GENETIC PATHWAYS THAT TYPIFY THIS PROCESS. ALTERED DNA METHYLATION MAY UNDERLIE THESE DEFECTS, BUT FEW REGIONS WITH DIFFERENTIAL METHYLATION HAVE BEEN IMPLICATED IN THE DISEASE. WE MAPPED GENOME-WIDE DIFFERENCES IN DNA METHYLATION BETWEEN HEALTHY HUMAN ENDOMETRIAL AND ENDOMETRIOTIC STROMAL CELLS AND CORRELATED THIS WITH GENE EXPRESSION USING AN INTERACTION ANALYSIS STRATEGY. WE IDENTIFIED 42,248 DIFFERENTIALLY METHYLATED CPGS IN ENDOMETRIOSIS COMPARED TO HEALTHY CELLS. THESE EXTENSIVE DIFFERENCES WERE NOT UNIDIRECTIONAL, BUT WERE FOCUSED INTRAGENICALLY AND AT SITES DISTAL TO CLASSIC CPG ISLANDS WHERE METHYLATION STATUS WAS TYPICALLY NEGATIVELY CORRELATED WITH GENE EXPRESSION. SIGNIFICANT DIFFERENCES IN METHYLATION WERE MAPPED TO 403 GENES, WHICH INCLUDED A DISPROPORTIONALLY LARGE NUMBER OF TRANSCRIPTION FACTORS. FURTHERMORE, MANY OF THESE GENES ARE IMPLICATED IN THE PATHOLOGY OF ENDOMETRIOSIS AND DECIDUALIZATION. OUR RESULTS TREMENDOUSLY IMPROVE THE SCOPE AND RESOLUTION OF DIFFERENTIAL METHYLATION AFFECTING THE HOX GENE CLUSTERS, NUCLEAR RECEPTOR GENES, AND INTRIGUINGLY THE GATA FAMILY OF TRANSCRIPTION FACTORS. FUNCTIONAL ANALYSIS OF THE GATA FAMILY REVEALED THAT GATA2 REGULATES KEY GENES NECESSARY FOR THE HORMONE-DRIVEN DIFFERENTIATION OF HEALTHY STROMAL CELLS, BUT IS HYPERMETHYLATED AND REPRESSED IN ENDOMETRIOTIC CELLS. GATA6, WHICH IS HYPOMETHYLATED AND ABUNDANT IN ENDOMETRIOTIC CELLS, POTENTLY BLOCKED HORMONE SENSITIVITY, REPRESSED GATA2, AND INDUCED MARKERS OF ENDOMETRIOSIS WHEN EXPRESSED IN HEALTHY ENDOMETRIAL CELLS. THE UNIQUE EPIGENETIC FINGERPRINT IN ENDOMETRIOSIS SUGGESTS DNA METHYLATION IS AN INTEGRAL COMPONENT OF THE DISEASE, AND IDENTIFIES A NOVEL ROLE FOR THE GATA FAMILY AS KEY REGULATORS OF UTERINE PHYSIOLOGY-ABERRANT DNA METHYLATION IN ENDOMETRIOTIC CELLS CORRELATES WITH A SHIFT IN GATA ISOFORM EXPRESSION THAT FACILITATES PROGESTERONE RESISTANCE AND DISEASE PROGRESSION. 2014 4 3503 24 IDENTIFICATION OF POTENTIAL DIFFERENTIALLY METHYLATED GENE-RELATED BIOMARKERS IN ENDOMETRIOSIS. AIM: TO IDENTIFY EPIGENETIC ALTERATIONS OF DIFFERENTIALLY EXPRESSED GENES AND SCREEN OUT TARGETED THERAPEUTIC DRUGS IN ENDOMETRIOSIS. METHODS: BASED ON THE GENE EXPRESSION OMNIBUS DATABASE AND A SERIES OF BIOLOGICAL INFORMATION ANALYSIS TOOLS, SUPPLEMENTED BY VALIDATION OF CLINICAL SAMPLES, ABERRANT DNA METHYLATION-DRIVEN GENES AND THEIR FUNCTIONS WERE EXPLORED, AS WELL AS POSSIBLE TARGETED DRUGS. RESULTS: THIS STUDY SCREENED OUT A RANGE OF DNA METHYLATION-DRIVEN GENES THAT WERE ASSOCIATED WITH POWERFUL PROPERTIES AND CORRESPONDING PATHWAYS. AMONG THEM, BDNF AND CCL2 WERE KEY GENES IN THE DEVELOPMENT OF ENDOMETRIOSIS. FOUR CHEMICAL AGENTS HAVE BEEN FLAGGED AS POTENTIAL TREATMENTS FOR ENDOMETRIOSIS. CONCLUSION: THESE CANDIDATE GENES AND SMALL-MOLECULE AGENTS MAY BE FURTHER EXPLORED AS POTENTIAL TARGETS AND DRUGS FOR ENDOMETRIOSIS DIAGNOSIS AND THERAPY, RESPECTIVELY. 2022 5 468 40 ARGININE METHYLTRANSFERASES MEDIATE AN EPIGENETIC OVARIAN RESPONSE TO ENDOMETRIOSIS. ENDOMETRIOSIS IS ASSOCIATED WITH INFERTILITY AND DEBILITATING CHRONIC PAIN. ABNORMAL EPIGENETIC MODIFICATIONS IN THE HUMAN ENDOMETRIUM HAVE RECENTLY BEEN IMPLICATED IN THE PATHOGENESIS OF THIS CONDITION. HOWEVER, WHETHER AN ALTERED EPIGENETIC LANDSCAPE CONTRIBUTES TO PATHOLOGICAL CHANGES IN THE OVARY IS UNKNOWN. USING AN ESTABLISHED BABOON ENDOMETRIOSIS MODEL, EARLY-, AND LATE-STAGE EPIGENETIC CHANGES IN THE OVARY WERE INVESTIGATED. TRANSCRIPT PROFILING OF KEY CHROMATIN-MODIFYING ENZYMES USING PATHWAY-FOCUSED PCR ARRAYS ON OVARIAN TISSUE FROM HEALTHY CONTROL ANIMALS AND AT 3 AND 15 MONTHS OF ENDOMETRIOSIS REVEALED DRAMATIC CHANGES IN GENE EXPRESSION IN A DISEASE DURATION-DEPENDENT MANNER. INGENUITY PATHWAY ANALYSIS INDICATED THAT TRANSCRIPTS FOR CHROMATIN-REMODELING ENZYMES ASSOCIATED WITH REPRODUCTIVE SYSTEM DISEASE AND CANCER DEVELOPMENT WERE ABNORMALLY REGULATED, MOST PROMINENTLY THE ARGININE METHYLTRANSFERASES CARM1, PRMT2, AND PRMT8. DOWNREGULATION OF CARM1 PROTEIN EXPRESSION WAS ALSO DETECTED IN THE OVARY, FULLY-GROWN OOCYTES AND EUTOPIC ENDOMETRIUM FOLLOWING 15 MONTHS OF ENDOMETRIOSIS. SODIUM BISULFITE SEQUENCING REVEALED DNA HYPERMETHYLATION WITHIN THE PRMT8 PROMOTER, SUGGESTING THAT DEREGULATED CPG METHYLATION MAY PLAY A ROLE IN TRANSCRIPTIONAL REPRESSION OF THIS GENE. THESE RESULTS DEMONSTRATE THAT ENDOMETRIOSIS IS ASSOCIATED WITH CHANGES OF EPIGENETIC PROFILES IN THE PRIMATE OVARY AND SUGGEST THAT ARGININE METHYLTRANSFERASES PLAY A PROMINENT ROLE IN MEDIATING THE OVARIAN RESPONSE TO ENDOMETRIOSIS. OWING TO THE CRITICAL ROLE OF CARM1 IN NUCLEAR RECEPTOR-MEDIATED TRANSCRIPTION AND MAINTENANCE OF PLURIPOTENCY IN THE CLEAVAGE STAGE EMBRYO, OUR RESULTS SUGGEST THAT EPIGENETIC ALTERATIONS IN THE OVARY MAY HAVE FUNCTIONAL CONSEQUENCES FOR OOCYTE QUALITY AND THE ETIOLOGY OF INFERTILITY ASSOCIATED WITH ENDOMETRIOSIS. 2015 6 352 41 ALTERED GENE EXPRESSION OF VEGF, IGFS AND H19 LNCRNA AND EPIGENETIC PROFILE OF H19-DMR REGION IN ENDOMETRIAL TISSUES OF WOMEN WITH ENDOMETRIOSIS. BACKGROUND: ENDOMETRIOSIS, AS CHRONIC ESTROGEN-DEPENDENT DISEASE, IS DEFINED BY THE PRESENCE OF ENDOMETRIAL-LIKE TISSUE OUTSIDE THE UTERUS. PROLIFERATION OF ENDOMETRIAL TISSUE AND NEOANGIOGENESIS ARE CRITICAL FACTORS IN DEVELOPMENT OF ENDOMETRIOSIS. HENCE, VASCULAR ENDOTHELIAL GROWTH FACTOR (VEGF) AS WELL AS INSULIN-LIKE GROWTH FACTOR 1 AND 2 (IGF1, 2) MAY BE INVOLVED AS INDUCERS OF CELLULAR PROLIFERATION OR NEOANGIOGENESIS. IMPRINTED LONG NONCODING RNA H19 (LNCRNA H19) HAS BEEN SUGGESTED TO BE INVOLVED IN PATHOGENESIS OF ENDOMETRIOSIS VIA REGULATION OF CELLULAR PROLIFERATION AND DIFFERENTIATION. EPIGENETIC ABERRATIONS APPEAR TO PLAY AN IMPORTANT ROLE IN ITS PATHOGENESIS. THE PRESENT STUDY WAS DESIGNED TO ELUCIDATE VEGF, IGF1, IGF2 AND H19 LNCRNA GENES EXPRESSION AND EPIGENETIC ALTERATIONS OF DIFFERENTIALLY METHYLATED REGION (DMR) OF H19 (H19-DMR) REGULATORY REGION IN ENDOMETRIAL TISSUES OF PATIENTS WITH ENDOMETRIOSIS, IN COMPARISON WITH CONTROL WOMEN. METHODS: IN THIS CASE-CONTROL STUDY, 24 WOMEN WITH AND WITHOUT ENDOMETRIOSIS WERE STUDIED FOR THE RELATIVE EXPRESSION OF VEGF, IGF1, IGF2 AND H19 LNCRNA GENES USING REAL-TIME POLYMERASE CHAIN REACTION (PCR) TECHNIQUE. OCCUPANCY OF THE MECP2 ON DMR REGION OF H19 GENE WAS ASSESSED USING CHROMATIN IMMUNOPRECIPITATION (CHIP), FOLLOWED BY REAL-TIME PCR. RESULTS: GENES EXPRESSION PROFILE OF H19, IGF1 AND IGF2 WAS DECREASED IN EUTOPIC AND ECTOPIC ENDOMETRIAL TISSUES OF ENDOMETRIOSIS GROUP, COMPARED TO THE CONTROL TISSUES. DECREASED EXPRESSION OF H19 IN ECTOPIC SAMPLES WAS SIGNIFICANT IN COMPARISON WITH THE CONTROLS (P < 0.05). GENE EXPRESSION OF VEGF WAS INCREASED IN EUTOPIC TISSUES OF ENDOMETRIOSIS GROUP, COMPARED TO CONTROL GROUP. WHEREAS ITS EXPRESSION LEVEL WAS LOWER IN ECTOPIC LESIONS VERSUS EUTOPIC AND CONTROL ENDOMETRIAL SAMPLES. CHIP ANALYSIS REVEALED SIGNIFICANT AND NEARLY SIGNIFICANT HYPOMETHYLATION OF H19-DMR REGION II IN EUTOPIC AND ECTOPIC SAMPLES, COMPARED TO THE CONTROL GROUP RESPECTIVELY. THIS EPIGENETIC CHANGE WAS ALIGNED WITH EXPRESSION OF IGF2. WHILE METHYLATION OF H19-DMR REGION I WAS NOT SIGNIFICANTLY DIFFERENT BETWEEN THE EUTOPIC, ECTOPIC AND CONTROL ENDOMETRIAL SAMPLES. CONCLUSION: THESE DATA SHOWED THAT VEGF, IGF1, IGF2 AND H19 LNCRNA GENES EXPRESSION AND EPIGENETIC ALTERATIONS OF H19 LNCRNA HAVE DYNAMIC ROLE IN THE PATHOGENESIS OF ENDOMETRIOSIS, SPECIFICALLY IN THE WAY THAT HYPOMETHYLATION OF H19-DMR REGION II CAN BE INVOLVED IN IGF2 DYSREGULATION IN ENDOMETRIOSIS. 2022 7 1202 35 COULD DNA HYDROXYMETHYLATION BE CRUCIAL IN INFLUENCING STEROID HORMONE SIGNALING IN ENDOMETRIAL BIOLOGY AND ENDOMETRIOSIS? ENDOMETRIOSIS AFFECTS 10% OF REPRODUCTIVE-AGED WOMEN. IT IS CHARACTERIZED BY THE GROWTH OF THE ENDOMETRIUM, OUTSIDE THE UTERUS AND IS ASSOCIATED WITH INFERTILITY AND CHRONIC ABDOMINAL PAIN. LACK OF NONINVASIVE DIAGNOSTIC TOOLS AND EARLY SCREENING TESTS RESULTS IN DELAYED TREATMENT AND SUBSEQUENTLY INCREASED DISEASE SEVERITY. ENDOMETRIOSIS IS A DISEASE ASSOCIATED WITH A DEREGULATED HORMONAL RESPONSE, THEREFORE, UNDERSTANDING THE MOLECULAR MECHANISMS THAT GOVERN THIS HORMONAL INTERPLAY IS OF PARAMOUNT IMPORTANCE. DNA METHYLATION IS AN EPIGENETIC MARK THAT REGULATES GENE EXPRESSION AND IS OFTEN ASSOCIATED WITH GENES THAT CODE FOR STEROID RECEPTORS AND ENZYMES ASSOCIATED WITH ESTROGEN SYNTHESIS AND METABOLISM IN ENDOMETRIOSIS. DNA HYDROXYMETHYLATION, WHICH IS STRUCTURALLY SIMILAR TO METHYLATION BUT FUNCTIONALLY DIFFERENT, IS A BIOLOGICALLY CRITICAL MECHANISM THAT IS ALSO KNOWN TO REGULATE GENE EXPRESSION. TEN ELEVEN TRANSLOCATION (TET) PROTEINS MEDIATE HYDROXYMETHYLATION. HOWEVER, THE ROLE OF DNA HYDROXYMETHYLATION OR TETS IN THE ENDOMETRIUM REMAINS RELATIVELY UNEXPLORED. CURRENTLY, THE "GOLD STANDARD" TECHNIQUE USED TO STUDY METHYLATION PATTERNS IS BISULFITE GENOMIC SEQUENCING. THIS TECHNIQUE ALSO DETECTS HYDROXYMETHYLATION BUT FAILS TO DISTINGUISH BETWEEN THE TWO, THEREBY LIMITING OUR UNDERSTANDING OF THESE TWO PROCESSES. THE PRESENCE OF TETS IN THE MALE AND FEMALE REPRODUCTIVE TRACT AND ITS CONTRIBUTION TO ENDOMETRIAL CANCER MAKES IT AN IMPORTANT FACTOR TO STUDY IN ENDOMETRIOSIS. THIS REVIEW SUMMARIZES THE ROLE OF DNA METHYLATION IN ABERRANT STEROID HORMONE SIGNALING AND HYPOTHESIZES THAT HYDROXYMETHYLATION COULD BE A FACTOR INFLUENCING HORMONAL INSTABILITY SEEN IN ENDOMETRIOSIS. 2020 8 5239 43 PROGESTERONE ALLEVIATES ENDOMETRIOSIS VIA INHIBITION OF UTERINE CELL PROLIFERATION, INFLAMMATION AND ANGIOGENESIS IN AN IMMUNOCOMPETENT MOUSE MODEL. ENDOMETRIOSIS, DEFINED AS GROWTH OF THE ENDOMETRIAL CELLS OUTSIDE THE UTERUS, IS AN INFLAMMATORY DISORDER THAT IS ASSOCIATED WITH CHRONIC PELVIC PAIN AND INFERTILITY IN WOMEN OF CHILDBEARING AGE. ALTHOUGH THE ESTROGEN-DEPENDENCE OF ENDOMETRIOSIS IS WELL KNOWN, THE ROLE OF PROGESTERONE IN DEVELOPMENT OF THIS DISEASE REMAINS POORLY UNDERSTOOD. IN THIS STUDY, WE DEVELOPED A DISEASE MODEL IN WHICH ENDOMETRIOSIS WAS INDUCED IN THE PERITONEAL CAVITIES OF IMMUNOCOMPETENT FEMALE MICE, AND MAINTAINED WITH EXOGENOUS ESTROGEN. THE ENDOMETRIOSIS-LIKE LESIONS THAT WERE IDENTIFIED AT A VARIETY OF ECTOPIC LOCATIONS EXHIBITED ABUNDANT BLOOD SUPPLY AND EXTENSIVE ADHESIONS. HISTOLOGICAL EXAMINATION REVEALED THAT THESE LESIONS HAD A WELL-ORGANIZED ENDOMETRIAL ARCHITECTURE AND FIBROTIC RESPONSE, RESEMBLING THOSE RECOVERED FROM CLINICAL PATIENTS. IN ADDITION, AN EXTENSIVE PROLIFERATION, INFLAMMATORY RESPONSE, AND LOSS OF ESTROGEN RECEPTOR ALPHA (ERALPHA) AND PROGESTERONE RECEPTOR (PR) EXPRESSION WERE ALSO OBSERVED IN THESE LESIONS. INTERESTINGLY, ADMINISTRATION OF PROGESTERONE BEFORE, BUT NOT AFTER, LESION INDUCTION SUPPRESSED LESION EXPANSION AND MAINTAINED ERALPHA AND PR EXPRESSIONS. THESE PROGESTERONE-PRETREATED LESIONS EXHIBITED ATTENUATION IN KI67, CD31, AND PRO-INFLAMMATORY CYTOKINE EXPRESSION AS WELL AS MACROPHAGE INFILTRATION, INDICATING THAT PROGESTERONE AMELIORATES ENDOMETRIOSIS PROGRESSION BY INHIBITING CELL PROLIFERATION, INFLAMMATION AND NEOVASCULARIZATION. OUR STUDIES FURTHER SHOWED THAT SUPPRESSION OF GLOBAL DNA METHYLATION BY APPLICATION OF DNA METHYLTRANSFERASE INHIBITOR TO FEMALE MICE BEARING ECTOPIC LESIONS RESTRAINED LESION EXPANSION AND RESTORED ERALPHA AND PR EXPRESSION IN EUTOPIC ENDOMETRIUM AND ECTOPIC LESIONS. THESE RESULTS INDICATE THAT EPIGENETIC REGULATION OF TARGET GENE EXPRESSION VIA DNA METHYLATION CONTRIBUTES, AT LEAST IN PART, TO PROGESTERONE RESISTANCE IN ENDOMETRIOSIS. 2016 9 3139 30 GLOBAL ENDOMETRIAL DNA METHYLATION ANALYSIS REVEALS INSIGHTS INTO MQTL REGULATION AND ASSOCIATED ENDOMETRIOSIS DISEASE RISK AND ENDOMETRIAL FUNCTION. ENDOMETRIOSIS IS A LEADING CAUSE OF PAIN AND INFERTILITY AFFECTING MILLIONS OF WOMEN GLOBALLY. HEREIN, WE CHARACTERIZE VARIATION IN DNA METHYLATION (DNAM) AND ITS ASSOCIATION WITH MENSTRUAL CYCLE PHASE, ENDOMETRIOSIS, AND GENETIC VARIANTS THROUGH ANALYSIS OF GENOTYPE DATA AND METHYLATION IN ENDOMETRIAL SAMPLES FROM 984 DEEPLY-PHENOTYPED PARTICIPANTS. WE ESTIMATE THAT 15.4% OF THE VARIATION IN ENDOMETRIOSIS IS CAPTURED BY DNAM AND IDENTIFY SIGNIFICANT DIFFERENCES IN DNAM PROFILES ASSOCIATED WITH STAGE III/IV ENDOMETRIOSIS, ENDOMETRIOSIS SUB-PHENOTYPES AND MENSTRUAL CYCLE PHASE, INCLUDING OPENING OF THE WINDOW FOR EMBRYO IMPLANTATION. MENSTRUAL CYCLE PHASE WAS A MAJOR SOURCE OF DNAM VARIATION SUGGESTING CELLULAR AND HORMONALLY-DRIVEN CHANGES ACROSS THE CYCLE CAN REGULATE GENES AND PATHWAYS RESPONSIBLE FOR ENDOMETRIAL PHYSIOLOGY AND FUNCTION. DNAM QUANTITATIVE TRAIT LOCUS (MQTL) ANALYSIS IDENTIFIED 118,185 INDEPENDENT CIS-MQTLS INCLUDING 51 ASSOCIATED WITH RISK OF ENDOMETRIOSIS, HIGHLIGHTING CANDIDATE GENES CONTRIBUTING TO DISEASE RISK. OUR WORK PROVIDES FUNCTIONAL EVIDENCE FOR EPIGENETIC TARGETS CONTRIBUTING TO ENDOMETRIOSIS RISK AND PATHOGENESIS. DATA GENERATED SERVE AS A VALUABLE RESOURCE FOR UNDERSTANDING TISSUE-SPECIFIC EFFECTS OF METHYLATION ON ENDOMETRIAL BIOLOGY IN HEALTH AND DISEASE. 2023 10 3003 39 GENETIC, EPIGENETIC AND STEM CELL ALTERATIONS IN ENDOMETRIOSIS: NEW INSIGHTS AND POTENTIAL THERAPEUTIC PERSPECTIVES. HUMAN ENDOMETRIUM IS A HIGHLY DYNAMIC TISSUE, UNDERGOING PERIODIC GROWTH AND REGRESSION AT EACH MENSTRUAL CYCLE. ENDOMETRIOSIS IS A FREQUENT CHRONIC PATHOLOGICAL STATUS CHARACTERIZED BY ENDOMETRIAL TISSUE WITH AN ECTOPIC LOCALIZATION, CAUSING PELVIC PAIN AND INFERTILITY AND A VARIABLE CLINICAL PRESENTATION. IN ADDITION, THERE IS WELL-ESTABLISHED EVIDENCE THAT, ALTHOUGH ENDOMETRIOSIS IS CONSIDERED BENIGN, IT IS ASSOCIATED WITH AN INCREASED RISK OF MALIGNANT TRANSFORMATION IN APPROXIMATELY 1.0% OF AFFECTED WOMEN, WITH THE INVOLVEMENT OF MULTIPLE PATHWAYS OF DEVELOPMENT. INCREASING EVIDENCE SUPPORTS A KEY CONTRIBUTION OF DIFFERENT STEM/PROGENITOR CELL POPULATIONS NOT ONLY IN THE CYCLIC REGENERATION OF EUTOPIC ENDOMETRIUM, BUT ALSO IN THE PATHOGENESIS OF AT LEAST SOME TYPES OF ENDOMETRIOSIS. EVIDENCE HAS ARISEN FROM EXPERIMENTS IN ANIMAL MODELS OF DISEASE THROUGH DIFFERENT KINDS OF ASSAYS (INCLUDING CLONOGENICITY, THE LABEL-RETAINING CELL APPROACH, THE ANALYSIS OF UNDIFFERENTIATION MARKERS), AS WELL AS FROM DESCRIPTIVE STUDIES ON ECTOPIC AND EUTOPIC TISSUE SAMPLES HARVESTED FROM AFFECTED WOMEN. CHANGES IN STEM CELL POPULATIONS IN ENDOMETRIOTIC LESIONS ARE ASSOCIATED WITH GENETIC AND EPIGENETIC ALTERATIONS, INCLUDING IMBALANCE OF MIRNA EXPRESSION, HISTONE AND DNA MODIFICATIONS AND CHROMOSOMAL ABERRATIONS. THE PRESENT SHORT REVIEW MAINLY SUMMARIZES THE LATEST OBSERVATIONS CONTRIBUTING TO THE CURRENT KNOWLEDGE REGARDING THE PRESENCE AND THE POTENTIAL CONTRIBUTION OF STEM/PROGENITOR CELLS IN EUTOPIC ENDOMETRIUM AND THE AETIOLOGY OF ENDOMETRIOSIS, TOGETHER WITH A REPORT OF THE MOST RECENTLY IDENTIFIED GENETIC AND EPIGENETIC ALTERATIONS IN ENDOMETRIOSIS. WE ALSO DESCRIBE THE POTENTIAL ADVANTAGES OF SINGLE CELL MOLECULAR PROFILING IN ENDOMETRIUM AND IN ENDOMETRIOTIC LESIONS. ALL THESE DATA CAN HAVE CLINICAL IMPLICATIONS AND PROVIDE A BASIS FOR NEW POTENTIAL THERAPEUTIC APPLICATIONS. 2014 11 5754 23 SOCIAL PSYCHOGENIC STRESS PROMOTES THE DEVELOPMENT OF ENDOMETRIOSIS IN MOUSE. EXPOSURE TO CHRONIC STRESS BEFORE AND WELL AFTER THE INDUCTION OF ENDOMETRIOSIS IS REPORTED TO INCREASE LESION SIZES IN RATS, BUT IT IS UNCLEAR WHETHER STRESS, EXPOSED SHORTLY AFTER THE INDUCTION OF ENDOMETRIOSIS, WOULD ALSO PROMOTE THE DEVELOPMENT OF ENDOMETRIOSIS, NOR IS IT CLEAR WHAT THE UNDERLYING POSSIBLE MOLECULAR MECHANISM IS. THIS STUDY WAS UNDERTAKEN TO TEST THE HYPOTHESIS THAT CHRONIC STRESS CAN PROMOTE THE DEVELOPMENT OF ENDOMETRIOSIS. A PROSPECTIVE RANDOMIZED MOUSE EXPERIMENT WAS CONDUCTED THAT SUBJECTED MICE WITH INDUCED ENDOMETRIOSIS TO PREDATOR STRESS. IN ADDITION, A CROSS-SECTIONAL IMMUNOHISTOCHEMISTRY STUDY WAS PERFORMED IN ECTOPIC AND EUTOPIC ENDOMETRIAL TISSUE SAMPLES FROM AGE- AND ROUGHLY MENSTRUAL PHASE-MATCHED WOMEN WITH OVARIAN ENDOMETRIOMAS. IT WAS FOUND THAT THE CHRONIC PSYCHOGENIC STRESS INDUCED EPIGENETIC CHANGES IN THE HIPPOCAMPUS IN MOUSE INDEPENDENT OF ENDOMETRIOSIS. IT WAS ALSO FOUND THAT CHRONIC PSYCHOGENIC STRESS INDUCED EPIGENETIC CHANGES IN THE HIPPOCAMPUS OF MICE WITH ENDOMETRIOSIS, AND SEEMINGLY ACTIVATED THE ADRENERGIC SIGNALLING IN ECTOPIC ENDOMETRIUM, RESULTING IN INCREASED ANGIOGENESIS AND ACCELERATED GROWTH OF ENDOMETRIOTIC LESIONS. THUS, CHRONIC PSYCHOGENIC STRESS PROMOTES ENDOMETRIOSIS DEVELOPMENT, RAISING THE POSSIBILITY THAT THE USE OF ANTI-DEPRESSANTS IN CASES OF PROLONGED AND INTENSE STRESS MIGHT FORESTALL THE NEGATIVE IMPACT OF STRESS ON THE DEVELOPMENT OF ENDOMETRIOSIS. 2017 12 2400 39 EPIGENETIC REPROGRAMMING OF IMMUNE CELLS IN WOMEN WITH PCOS IMPACT GENES CONTROLLING REPRODUCTIVE FUNCTION. CONTEXT: POLYCYSTIC OVARY SYNDROME (PCOS) IS A CHRONIC DISEASE AFFECTING REPRODUCTIVE FUNCTION AND WHOLE-BODY METABOLISM. ALTHOUGH THE ETIOLOGY IS UNCLEAR, EMERGING EVIDENCE INDICATES THAT THE EPIGENETICS MAY BE A CONTRIBUTING FACTOR. OBJECTIVE: TO DETERMINE THE ROLE OF GLOBAL AND GENOME-WIDE EPIGENETIC MODIFICATIONS IN SPECIFIC IMMUNE CELLS IN PCOS COMPARED WITH CONTROLS AND WHETHER THESE COULD BE RELATED TO CLINICAL FEATURES OF PCOS. DESIGN: CROSS-SECTIONAL STUDY. PARTICIPANTS: WOMEN WITH (N = 17) OR WITHOUT PCOS (N = 17). SETTING: RECRUITED FROM THE GENERAL COMMUNITY. MAIN OUTCOME MEASURES: ISOLATED PERIPHERAL BLOOD MONONUCLEAR CELLS WERE ANALYZED USING MULTICOLOR FLOW CYTOMETRY METHODS TO DETERMINE GLOBAL DNA METHYLATION LEVELS IN A CELL-SPECIFIC FASHION. TRANSCRIPTOMIC AND GENOME-WIDE DNA METHYLATION ANALYSES WERE PERFORMED ON T HELPER CELLS USING RNA SEQUENCING AND REDUCED REPRESENTATION BISULFITE SEQUENCING. RESULTS: WOMEN WITH PCOS HAD LOWER GLOBAL DNA METHYLATION IN MONOCYTES (P = 0.006) AND IN T HELPER (P = 0.004), T CYTOTOXIC (P = 0.004), AND B CELLS (P = 0.03). SPECIFIC GENOME-WIDE DNA METHYLATION ANALYSIS OF T HELPER CELLS FROM WOMEN WITH PCOS IDENTIFIED 5581 DIFFERENTIALLY METHYLATED CPG SITES. FUNCTIONAL GENE ONTOLOGY ENRICHMENT ANALYSIS SHOWED THAT GENES LOCATED AT THE PROXIMITY OF DIFFERENTIALLY METHYLATED CPG SITES BELONG TO PATHWAYS RELATED TO REPRODUCTIVE FUNCTION AND IMMUNE CELL FUNCTION. HOWEVER, THESE GENES WERE NOT ALTERED AT THE TRANSCRIPTOMIC LEVEL. CONCLUSIONS: IT WAS SHOWN THAT PCOS IS ASSOCIATED WITH GLOBAL AND GENE-SPECIFIC DNA METHYLATION REMODELING IN A CELL TYPE-SPECIFIC MANNER. FURTHER INVESTIGATION IS WARRANTED TO DETERMINE WHETHER EPIGENETIC REPROGRAMMING OF IMMUNE CELLS IS IMPORTANT IN DETERMINING THE DIFFERENT PHENOTYPES OF PCOS. 2019 13 1500 45 DNA METHYLATION ANALYSIS OF CD4+ T CELLS IN PATIENTS WITH PSORIASIS. PSORIASIS IS A CHRONIC INFLAMMATORY SKIN DISEASE THAT IS CHARACTERIZED BY ABERRANT CROSS-TALK BETWEEN KERATINOCYTES AND IMMUNE CELLS SUCH AS CD4+ T CELLS, RESULTING IN KERATINOCYTE HYPERPROLIFERATION IN THE EPIDERMIS. DNA METHYLATION, ONE OF SEVERAL EPIGENETIC MECHANISMS, PLAYS AN IMPORTANT ROLE IN GENE EXPRESSION WITHOUT CHANGING THE DNA SEQUENCE. SEVERAL STUDIES HAVE SUGGESTED THE INVOLVEMENT OF EPIGENETIC REGULATION IN SKIN LESIONS FROM PATIENTS WITH PSORIASIS. IN THIS STUDY, WE INVESTIGATED THE GENOME-WIDE DNA METHYLATION STATUS OF CD4+ T CELLS IN PATIENTS WITH PSORIASIS COMPARED WITH HEALTHY SUBJECTS USING METHYLATED DNA IMMUNOPRECIPITATION SEQUENCING (MEDIP-SEQ). THE RESULTS OF MEDIP-SEQ SHOWED THAT THE GLOBAL METHYLATION VALUES OF CD4+ T CELLS ARE HIGHER IN PATIENTS WITH PSORIASIS THAN IN HEALTHY CONTROLS, PARTICULARLY IN THE PROMOTER REGIONS. AMONG THE MOST HYPERMETHYLATED GENES IN THE PROMOTER REGIONS, WE SELECTED THE GENES WHOSE EXPRESSION IS SIGNIFICANTLY REDUCED IN THE CD4+ T CELLS OF PSORIASIS PATIENTS. STUDIES USING THE METHYLATION INHIBITOR 5-AZACYTIDINE IN VITRO METHYLATION ASSAYS HAVE SHOWN THAT THE DIFFERENTIAL EXPRESSION LEVELS WERE ASSOCIATED WITH THE METHYLATION STATUS OF EACH GENE. BISULFITE SEQUENCING OF THE TRANSCRIPTION START REGION OF PHOSPHATIDIC ACID PHOSPHATASE TYPE 2 DOMAIN CONTAINING 3 (PPAPDC3), ONE OF THE SELECTED GENES, SHOWED HYPERMETHYLATION IN THE CD4+ T CELLS OF PSORIASIS PATIENTS. THESE RESULTS SUGGESTED THAT THE METHYLATION STATUS, WHICH IS IDENTIFIED BY MEDIP-SEQ OF THE GENES, WAS CORRELATED WITH THE MRNA EXPRESSION LEVEL OF THE GENES. COLLECTIVELY, THE DNA METHYLATION STATUS IN CD4+ T CELLS MIGHT BE ASSOCIATED WITH THE PATHOGENESIS OF PSORIASIS. 2014 14 1508 40 DNA METHYLATION AND MRNA AND MICRORNA EXPRESSION OF SLE CD4+ T CELLS CORRELATE WITH DISEASE PHENOTYPE. SYSTEMIC LUPUS ERYTHEMATOSUS (SLE) IS AN AUTOIMMUNE DISEASE WELL KNOWN FOR ITS CLINICAL HETEROGENEITY, AND ITS ETIOLOGY SECONDARY TO A CROSS-TALK INVOLVING GENETIC PREDISPOSITION AND ENVIRONMENTAL STIMULI. ALTHOUGH GENOME-WIDE ANALYSIS HAS CONTRIBUTED GREATLY TO OUR UNDERSTANDING OF THE GENETIC BASIS OF SLE, THERE IS INCREASING EVIDENCE FOR A ROLE OF EPIGENETICS. INDEED, RECENT DATA HAVE DEMONSTRATED THAT IN PATIENTS WITH SLE, THERE ARE STRIKING ALTERATIONS OF DNA METHYLATION, HISTONE MODIFICATIONS, AND DEREGULATED MICRORNA EXPRESSION, THE SUM OF WHICH CONTRIBUTE TO OVER-EXPRESSION OF SELECT AUTOIMMUNE-RELATED GENES AND LOSS OF TOLERANCE. TO ADDRESS THIS ISSUE AT THE LEVEL OF CLINICAL PHENOTYPE, WE PERFORMED DNA METHYLATION, MRNA AND MICRORNA EXPRESSION SCREENING USING HIGH-THROUGHPUT SEQUENCING OF PURIFIED CD4+ T CELLS FROM PATIENTS WITH SLE, COMPARED TO AGE AND SEX MATCHED CONTROLS. IN PARTICULAR, WE STUDIED 42 PATIENTS WITH SLE AND DIVIDED THIS GROUP INTO THREE CLINICAL PHENOTYPES: A) THE PRESENCE OF SKIN LESIONS WITHOUT SIGNS OF SYSTEMIC PATHOLOGY; B) SKIN LESIONS BUT ALSO CHRONIC RENAL PATHOLOGY; AND C) SKIN LESIONS, CHRONIC RENAL PATHOLOGY AND POLYARTICULAR DISEASE. INTERESTINGLY, AND AS EXPECTED, SEQUENCING DATA REVEALED CHANGES IN DNA METHYLATION IN SLE COMPARED TO CONTROLS. HOWEVER, AND MORE IMPORTANTLY, ALTHOUGH THERE WERE COMMON METHYLATION CHANGES FOUND IN ALL GROUPS OF SLE COMPARED TO CONTROLS, THERE WAS SPECIFIC DNA METHYLATION CHANGES THAT CORRELATED WITH CLINICAL PHENOTYPE. THESE INCLUDED CHANGES IN THE NOVEL KEY TARGET GENES NLRP2, CD300LB AND S1PR3, AS WELL AS CHANGES IN THE CRITICAL PATHWAYS, INCLUDING THE ADHERENS JUNCTION AND LEUKOCYTE TRANSENDOTHELIAL MIGRATION. WE ALSO NOTED THAT A SIGNIFICANT PROPORTION OF GENES UNDERGOING DNA METHYLATION CHANGES WERE INVERSELY CORRELATED WITH GENE EXPRESSION AND THAT MIRNA SCREENING REVEALED THE EXISTENCE OF SUBSETS WITH CHANGES IN EXPRESSION. INTEGRATED ANALYSIS OF THIS DATA HIGHLIGHTS SPECIFIC SETS OF MIRNAS CONTROLLED BY DNA METHYLATION, AND GENES THAT ARE ALTERED BY METHYLATION AND TARGETED BY MIRNAS. IN CONCLUSION, OUR FINDINGS SUGGEST SELECT EPIGENETIC MECHANISMS THAT CONTRIBUTE TO CLINICAL PHENOTYPES AND FURTHER SHED LIGHT ON A NEW VENUE FOR BASIC SLE RESEARCH. 2014 15 2920 36 GENE-SET ANALYSIS IS SEVERELY BIASED WHEN APPLIED TO GENOME-WIDE METHYLATION DATA. MOTIVATION: DNA METHYLATION IS AN EPIGENETIC MARK THAT CAN STABLY REPRESS GENE EXPRESSION. BECAUSE OF ITS BIOLOGICAL AND CLINICAL SIGNIFICANCE, SEVERAL METHODS HAVE BEEN DEVELOPED TO COMPARE GENOME-WIDE PATTERNS OF METHYLATION BETWEEN GROUPS OF SAMPLES. THE APPLICATION OF GENE SET ANALYSIS TO IDENTIFY RELEVANT GROUPS OF GENES THAT ARE ENRICHED FOR DIFFERENTIALLY METHYLATED GENES IS OFTEN A MAJOR COMPONENT OF THE ANALYSIS OF THESE DATA. THIS CAN BE USED, FOR EXAMPLE, TO IDENTIFY PROCESSES OR PATHWAYS THAT ARE PERTURBED IN DISEASE DEVELOPMENT. WE SHOW THAT GENE-SET ANALYSIS, AS IT IS TYPICALLY APPLIED TO GENOME-WIDE METHYLATION ASSAYS, IS SEVERELY BIASED AS A RESULT OF DIFFERENCES IN THE NUMBERS OF CPG SITES ASSOCIATED WITH DIFFERENT CLASSES OF GENES AND GENE PROMOTERS. RESULTS: WE DEMONSTRATE THIS BIAS USING PUBLISHED DATA FROM A STUDY OF DIFFERENTIAL CPG ISLAND METHYLATION IN LUNG CANCER AND A DATASET WE GENERATED TO STUDY METHYLATION CHANGES IN PATIENTS WITH LONG-STANDING ULCERATIVE COLITIS. WE SHOW THAT SEVERAL OF THE GENE SETS THAT SEEM ENRICHED WOULD ALSO BE IDENTIFIED WITH RANDOMIZED DATA. WE SUGGEST TWO EXISTING APPROACHES THAT CAN BE ADAPTED TO CORRECT THE BIAS. ACCOUNTING FOR THE BIAS IN THE LUNG CANCER AND ULCERATIVE COLITIS DATASETS PROVIDES NOVEL BIOLOGICAL INSIGHTS INTO THE ROLE OF METHYLATION IN CANCER DEVELOPMENT AND CHRONIC INFLAMMATION, RESPECTIVELY. OUR RESULTS HAVE SIGNIFICANT IMPLICATIONS FOR MANY PREVIOUS GENOME-WIDE METHYLATION STUDIES THAT HAVE DRAWN CONCLUSIONS ON THE BASIS OF SUCH STRONGLY BIASED ANALYSIS. CONTACT: CATHAL.SEOIGHE@NUIGALWAY.IE SUPPLEMENTARY INFORMATION: SUPPLEMENTARY DATA ARE AVAILABLE AT BIOINFORMATICS ONLINE. 2013 16 1583 37 DNA METHYLATION PROFILES OF BLOOD CELLS ARE DISTINCT BETWEEN EARLY-ONSET OBESE AND CONTROL INDIVIDUALS. OBESITY IS A HIGHLY PREVALENT, CHRONIC DISORDER THAT HAS BEEN INCREASING IN INCIDENCE IN YOUNG PATIENTS. BOTH EPIGENETIC AND GENETIC ABERRATIONS MAY PLAY A ROLE IN THE PATHOGENESIS OF OBESITY. THEREFORE, IN-DEPTH EPIGENOMIC AND GENOMIC ANALYSES WILL ADVANCE OUR UNDERSTANDING OF THE DETAILED MOLECULAR MECHANISMS UNDERLYING OBESITY AND AID IN THE SELECTION OF POTENTIAL BIOMARKERS FOR OBESITY IN YOUTH. HERE, WE PERFORMED MICROARRAY-BASED DNA METHYLATION AND GENE EXPRESSION PROFILING OF PERIPHERAL WHITE BLOOD CELLS OBTAINED FROM SIX YOUNG, OBESE INDIVIDUALS AND SIX HEALTHY CONTROLS. WE OBSERVED THAT THE HIERARCHICAL CLUSTERING OF DNA METHYLATION, BUT NOT GENE EXPRESSION, CLEARLY SEGREGATES THE OBESE INDIVIDUALS FROM THE CONTROLS, SUGGESTING THAT THE METABOLIC DISTURBANCE THAT OCCURS AS A RESULT OF OBESITY AT A YOUNG AGE MAY AFFECT THE DNA METHYLATION OF PERIPHERAL BLOOD CELLS WITHOUT ACCOMPANYING TRANSCRIPTIONAL CHANGES. TO EXAMINE THE GENOME-WIDE DIFFERENCES IN THE DNA METHYLATION PROFILES OF YOUNG OBESE AND CONTROL INDIVIDUALS, WE IDENTIFIED DIFFERENTIALLY METHYLATED CPG SITES AND INVESTIGATED THEIR GENOMIC AND EPIGENOMIC CONTEXTS. THE ABERRANT DNA METHYLATION PATTERNS IN OBESE INDIVIDUALS CAN BE SUMMARIZED AS RELATIVE GAINS AND LOSSES OF DNA METHYLATION IN GENE PROMOTERS AND GENE BODIES, RESPECTIVELY. WE ALSO OBSERVED THAT THE CPG ISLANDS OF OBESE INDIVIDUALS ARE MORE SUSCEPTIBLE TO DNA METHYLATION COMPARED TO CONTROLS. OUR PILOT STUDY SUGGESTS THAT THE GENOME-WIDE ABERRANT DNA METHYLATION PATTERNS OF OBESE INDIVIDUALS MAY ADVANCE NOT ONLY OUR UNDERSTANDING OF THE EPIGENOMIC PATHOGENESIS BUT ALSO EARLY SCREENING OF OBESITY IN YOUTH. 2017 17 2483 25 EPIGENETIC VARIATION AND HUMAN DISEASE. CYTOSINE GUANINE DINUCLEOTIDE (CPG) ISLAND METHYLATION IS A KNOWN MECHANISM OF EPIGENETIC INHERITANCE IN POSTMEIOTIC CELLS. THROUGH ASSOCIATED CHROMATIN CHANGES AND SILENCING, SUCH EPIGENETIC STATES CAN INFLUENCE CELLULAR PHYSIOLOGY AND AFFECT DISEASE RISK AND SEVERITY. OUR STUDIES OF CPG ISLAND METHYLATION IN NORMAL COLORECTAL MUCOSA REVEALED PROGRESSIVE AGE-RELATED INCREASES AT MULTIPLE GENE LOCI, SUGGESTING GENOME-WIDE MOLECULAR ALTERATIONS WITH POTENTIAL TO SILENCE GENE EXPRESSION. HOWEVER, THERE WAS CONSIDERABLE VARIATION IN THE DEGREE OF METHYLATION AMONG INDIVIDUALS OF COMPARABLE AGES. SUCH VARIATION COULD BE RELATED TO GENETIC FACTORS, LIFESTYLE, OR ENVIRONMENTAL EXPOSURES. STUDIES IN ULCERATIVE COLITIS AND HEPATOCELLULAR CIRRHOSIS AND NEOPLASIA REVEALED THAT CHRONIC INFLAMMATORY STATES ARE ACCOMPANIED BY MARKED INCREASES IN CPG ISLAND METHYLATION IN NORMAL-APPEARING TISSUES, CONFIRMING THE HYPOTHESIS THAT PROINFLAMMATORY EXPOSURES COULD ACCOUNT FOR PART OF THE EPIGENETIC VARIATION IN HUMAN POPULATIONS. PRELIMINARY DATA ALSO SUGGEST POTENTIAL INFLUENCES OF LIFESTYLE AND EXPOSURE FACTORS ON CPG ISLAND METHYLATION. IT IS SUGGESTED THAT EPIGENETIC VARIATION RELATED TO AGING, LIFESTYLE, EXPOSURES AND POSSIBLY GENETIC FACTORS, IS ONE OF THE MODULATORS OF ACQUIRED, AGE-RELATED HUMAN DISEASES, INCLUDING NEOPLASIA. 2002 18 3005 40 GENETIC, EPIGENETIC, AND STEROIDOGENIC MODULATION MECHANISMS IN ENDOMETRIOSIS. ENDOMETRIOSIS IS A CHRONIC GYNECOLOGICAL DISEASE, AFFECTING UP TO 10% OF REPRODUCTIVE-AGE WOMEN. THE EXACT CAUSE OF THE DISEASE IS UNKNOWN; HOWEVER, IT IS A HERITABLE CONDITION AFFECTED BY MULTIPLE GENETIC, EPIGENETIC, AND ENVIRONMENTAL FACTORS. PREVIOUS STUDIES REPORTED VARIATIONS IN THE EPIGENETIC PATTERNS OF NUMEROUS GENES KNOWN TO BE INVOLVED IN THE ABERRANT MODULATION OF CELL CYCLE STEROIDOGENESIS, ABNORMAL HORMONAL, IMMUNE AND INFLAMMATORY STATUS IN ENDOMETRIOSIS, APOPTOSIS, ADHESION, ANGIOGENESIS, PROLIFERATION, IMMUNE AND INFLAMMATORY PROCESSES, RESPONSE TO HYPOXIA, STEROIDOGENIC PATHWAY AND HORMONE SIGNALING ARE INVOLVED IN THE PATHOGENESIS OF ENDOMETRIOSIS. ACCUMULATING EVIDENCE SUGGEST THAT VARIOUS EPIGENETIC ABERRATIONS MAY CONTRIBUTE TO THE PATHOGENESIS OF ENDOMETRIOSIS. AMONG THEM, DNA METHYLTRANSFERASES, HISTONE DEACETYLATORS, AND NON-CODING MICRORNAS DEMONSTRATE DIFFERENTIAL EXPRESSION WITHIN ENDOMETRIOTIC LESIONS AND IN THE ENDOMETRIUM OF PATIENTS WITH ENDOMETRIOSIS. IT HAS BEEN INDICATED THAT THE IDENTIFICATION OF EPIGENETIC DIFFERENCES WITHIN THE DNA OR HISTONE PROTEINS MAY CONTRIBUTE TO THE DISCOVERY OF A USEFUL PROGNOSTIC BIOMARKER, WHICH COULD AID IN THE FUTURE EARLIER DETECTION, TIMELY DIAGNOSIS, AND INITIATION OF A NEW APPROACH TO THE TREATMENT OF ENDOMETRIOSIS, AS WELL AS INFORM US ABOUT THE EFFECTIVENESS OF TREATMENT AND THE STAGE OF THE DISEASE. AS THE ETIOLOGY OF ENDOMETRIOSIS IS HIGHLY COMPLEX AND STILL FAR FROM BEING FULLY ELUCIDATED, THE PRESENTED REVIEW FOCUSES ON DIFFERENT APPROACHES TO IDENTIFY THE GENETIC AND EPIGENETIC LINKS OF ENDOMETRIOSIS AND ITS PATHOGENESIS. 2020 19 3069 37 GENOME-WIDE DNA METHYLATION PROFILING IDENTIFIES EPIGENETIC CHANGES IN CD4+ AND CD14+ CELLS OF MULTIPLE SCLEROSIS PATIENTS. MULTIPLE SCLEROSIS (MS) IS A CHRONIC AUTOIMMUNE AND DEGENERATIVE DISEASE OF THE CENTRAL NERVOUS SYSTEM, WHICH DEVELOPS IN GENETICALLY PREDISPOSED INDIVIDUALS UPON EXPOSURE TO ENVIRONMENTAL INFLUENCES. ENVIRONMENTAL TRIGGERS OF MS, SUCH AS VIRAL INFECTIONS OR SMOKING, WERE DEMONSTRATED TO AFFECT DNA METHYLATION, AND THUS TO INVOLVE THIS IMPORTANT EPIGENETIC MECHANISM IN THE DEVELOPMENT OF PATHOLOGICAL PROCESS. TO IDENTIFY MS-ASSOCIATED DNA METHYLATION HALLMARKS, WE PERFORMED GENOME-WIDE DNA METHYLATION PROFILING OF TWO CELL POPULATIONS (CD4+ T-LYMPHOCYTES AND CD14+ MONOCYTES), COLLECTED FROM THE SAME TREATMENT-NAIVE RELAPSING-REMITTING MS PATIENTS AND HEALTHY SUBJECTS, USING ILLUMINA 450 K METHYLATION ARRAYS. WE REVEALED SIGNIFICANT CHANGES IN DNA METHYLATION FOR BOTH CELL POPULATIONS IN MS. IN CD4+ CELLS OF MS PATIENTS THE MAJORITY OF DIFFERENTIALLY METHYLATED POSITIONS (DMPS) WERE SHOWN TO BE HYPOMETHYLATED, WHILE IN CD14+ CELLS - HYPERMETHYLATED. DIFFERENTIAL METHYLATION OF HLA-DRB1 GENE IN CD4+ AND CD14+ CELLS WAS ASSOCIATED WITH CARRIAGE OF DRB1*15 ALLELE INDEPENDENTLY FROM THE DISEASE STATUS. BESIDES, ABOUT 20% OF IDENTIFIED DMPS WERE SHARED BETWEEN TWO CELL POPULATIONS AND HAD THE SAME DIRECTION OF METHYLATION CHANGES; THEY MAY BE INVOLVED IN BASIC EPIGENETIC PROCESSES OCCURING IN MS. THESE FINDINGS SUGGEST THAT THE EPIGENETIC MECHANISM OF DNA METHYLATION IN IMMUNE CELLS CONTRIBUTES TO MS; FURTHER STUDIES ARE NOW REQUIRED TO VALIDATE THESE RESULTS AND UNDERSTAND THEIR FUNCTIONAL SIGNIFICANCE. 2022 20 3726 32 INHIBITION OF HISTONE METHYLTRANSFERASE EZH2 SUPPRESSES ENDOMETRIOTIC VESICLE DEVELOPMENT IN A RAT MODEL OF ENDOMETRIOSIS. ENDOMETRIOSIS IS A PAINFUL GYNECOLOGICAL DISEASE WITH NO CURE AND LIMITED THERAPEUTIC OPTIONS. IT HAS BEEN HYPOTHESIZED THAT EPIGENETIC DRUGS CAN BE USED AS A NONHORMONAL TREATMENT FOR ENDOMETRIOSIS. THIS STUDY WAS CONDUCTED TO STUDY THE EFFICACY OF AN INHIBITOR OF THE HISTONE METHYLTRANSFERASE EZH2 USING AN ESTABLISHED RAT MODEL OF ENDOMETRIOSIS. WE HYPOTHESIZED THAT TREATMENT WILL BLOCK OR REDUCE THE NUMBER OF ENDOMETRIOTIC VESICLES IN THIS MODEL. WE CONDUCTED A PRECLINICAL DRUG STUDY IN FEMALE RATS WITH EXPERIMENTAL ENDOMETRIOSIS (UTERINE TISSUE TRANSPLANTED NEXT TO THE INTESTINAL MESENTERY) OR CONTROL SHAM (SUTURES ONLY). RATS WITH ENDOMETRIOSIS OR SHAM SURGERY RECEIVED EITHER TREATMENT WITH EZH2 INHIBITOR (5 MG/KG OR 10 MG/KG) OR VEHICLE (0.1%, 67% DMSO) EVERY OTHER DAY DURING 4 WEEKS. AFTER TREATMENT COMPLETION, THE NUMBER, AREA, VOLUME, AND WEIGHT OF VESICLES WERE EVALUATED. RT [2] PROFILER ARRAYS FOR NEUROPATHIC AND INFLAMMATION, EPITHELIAL TO MESENCHYMAL TRANSITION, INFLAMMATORY RESPONSE, AND AUTOIMMUNITY PATHWAYS WERE USED TO EXAMINE GENE EXPRESSION CHANGES IN THE VESICLES THAT DEVELOPED. TREATMENT WITH EZH2 INHIBITOR (10 MG/KG) SUPPRESSED THE DEVELOPMENT OF VESICLES, BY SIGNIFICANTLY DECREASING THE TOTAL VESICLE NUMBER, AREA, VOLUME, AND WEIGHT. IN ADDITION, EZH2 INHIBITION SIGNIFICANTLY INCREASED THE EXPRESSION OF CACNA1B AND FKBP1A GENES, INVOLVED IN PAIN AND PROLIFERATION, RESPECTIVELY. EZH2 INHIBITION SUPPRESSES THE GROWTH OF VESICLES WITHOUT APPARENT DETRIMENTAL EFFECTS TO OTHER ORGANS. TREATMENT WITH THIS EPIGENETIC INHIBITOR LEADS TO UPREGULATION OF A LIMITED NUMBER OF GENES RELATED TO ENDOMETRIOSIS-RELEVANT PATHWAYS. IN CONCLUSION, THESE DATA SUPPORT FOLLOW-UP STUDIES TO EVALUATE ITS POTENTIAL AS A THERAPEUTIC APPROACH FOR ENDOMETRIOSIS. 2020