1 6076 175 THE DYNAMICS OF NUCLEAR RECEPTORS AND NUCLEAR RECEPTOR COREGULATORS IN THE PATHOGENESIS OF ENDOMETRIOSIS. BACKGROUND: ENDOMETRIOSIS IS DEFINED AS THE COLONIZATION AND GROWTH OF ENDOMETRIAL TISSUE AT ANATOMIC SITES OUTSIDE THE UTERINE CAVITY. UP TO 15% OF REPRODUCTIVE-AGED WOMEN IN THE USA SUFFER FROM PAINFUL SYMPTOMS OF ENDOMETRIOSIS, SUCH AS INFERTILITY, PELVIC PAIN, MENSTRUAL CYCLE ABNORMALITIES AND INCREASED RISK OF CERTAIN CANCERS. HOWEVER, MANY OF THE CURRENT CLINICAL TREATMENTS FOR ENDOMETRIOSIS ARE NOT SUFFICIENTLY EFFECTIVE AND YIELD UNACCEPTABLE SIDE EFFECTS. THERE IS CLEARLY AN URGENT NEED TO IDENTIFY NEW MOLECULAR MECHANISMS THAT CRITICALLY UNDERPIN THE INITIATION AND PROGRESSION OF ENDOMETRIOSIS IN ORDER TO DEVELOP MORE SPECIFIC AND EFFECTIVE THERAPEUTICS WHICH LACK THE SIDE EFFECTS OF CURRENT THERAPIES. THE AIM OF THIS REVIEW IS TO DISCUSS HOW NUCLEAR RECEPTORS (NRS) AND THEIR COREGULATORS PROMOTE THE PROGRESSION OF ENDOMETRIOSIS. UNDERSTANDING THE PATHOGENIC MOLECULAR MECHANISMS FOR THE GENESIS AND MAINTENANCE OF ENDOMETRIOSIS AS MODULATED BY NRS AND COREGULATORS CAN REVEAL NEW THERAPEUTIC TARGETS FOR ALTERNATIVE ENDOMETRIOSIS TREATMENTS. METHODS: THIS REVIEW WAS PREPARED USING PUBLISHED GENE EXPRESSION MICROARRAY DATA SETS OBTAINED FROM PATIENTS WITH ENDOMETRIOSIS AND PUBLISHED LITERATURE ON NRS AND THEIR COREGULATORS THAT DEAL WITH ENDOMETRIOSIS PROGRESSION. USING THE ABOVE OBSERVATIONS, OUR CURRENT UNDERSTANDING OF HOW NRS AND NR COREGULATORS ARE INVOLVED IN THE PROGRESSION OF ENDOMETRIOSIS IS SUMMARIZED. RESULTS: ABERRANT LEVELS OF NRS AND NR COREGULATORS IN ECTOPIC ENDOMETRIOSIS LESIONS ARE ASSOCIATED WITH THE PROGRESSION OF ENDOMETRIOSIS. AS AN EXAMPLE, ENDOMETRIOTIC CELL-SPECIFIC ALTERATIONS IN GENE EXPRESSION ARE CORRELATED WITH A DIFFERENTIAL METHYLATION STATUS OF THE GENOME COMPARED WITH THE NORMAL ENDOMETRIUM. THESE DIFFERENTIAL EPIGENETIC REGULATIONS CAN GENERATE FAVORABLE CELL-SPECIFIC NR AND COREGULATOR MILIEUS FOR ENDOMETRIOSIS PROGRESSION. GENETIC ALTERATIONS, SUCH AS SINGLE NUCLEOTIDE POLYMORPHISMS AND INSERTION/DELETION POLYMORPHISMS OF NR AND COREGULATOR GENES, ARE FREQUENTLY DETECTED IN ECTOPIC LESIONS COMPARED WITH THE NORMAL ENDOMETRIUM. THESE GENETIC VARIATIONS IMPART NEW MOLECULAR PROPERTIES TO NRS AND COREGULATORS TO INCREASE THEIR CAPACITY TO STIMULATE PROGRESSION OF ENDOMETRIOSIS. FINALLY, POST-TRANSLATIONAL MODIFICATIONS OF NR COREGULATORS, SUCH AS PROTEOLYTIC PROCESSING, GENERATE ENDOMETRIOSIS-SPECIFIC ISOFORMS. COMPARED WITH THE UNMODIFIED COREGULATORS, THESE COREGULATOR ISOFORMS HAVE UNIQUE FUNCTIONS THAT ENHANCE THE PATHOGENESIS OF ENDOMETRIOSIS. CONCLUSIONS: EPIGENETIC/GENETIC VARIATIONS AND POSTTRANSLATIONAL MODIFICATIONS OF NRS AND COREGULATORS ALTER THEIR ORIGINAL FUNCTION SO THAT THEY BECOME POTENT 'DRIVERS' OF ENDOMETRIOSIS PROGRESSION. 2014 2 4770 47 NUCLEAR RECEPTORS AND EPIGENETIC REGULATION: OPPORTUNITIES FOR NUTRITIONAL TARGETING AND DISEASE PREVENTION. POSTTRANSLATIONAL MODIFICATIONS OF HISTONES, ALTERATIONS IN THE RECRUITMENT AND FUNCTIONS OF NON-HISTONE PROTEINS, DNA METHYLATION, AND CHANGES IN EXPRESSION OF NONCODING RNAS CONTRIBUTE TO CURRENT MODELS OF EPIGENETIC REGULATION. NUCLEAR RECEPTORS (NRS) ARE A GROUP OF TRANSCRIPTION FACTORS THAT, THROUGH LIGAND-BINDING, ACT AS SENSORS TO CHANGES IN NUTRITIONAL, ENVIRONMENTAL, DEVELOPMENTAL, PATHOPHYSIOLOGIC, AND ENDOCRINE CONDITIONS AND DRIVE ADAPTIVE RESPONSES VIA GENE REGULATION. ONE MECHANISM THROUGH WHICH NRS DIRECT GENE EXPRESSION IS THE ASSEMBLY OF TRANSCRIPTION COMPLEXES WITH COFACTORS AND COREGULATORS THAT POSSESS CHROMATIN-MODIFYING PROPERTIES. CHROMATIN MODIFICATIONS CAN BE TRANSIENT OR BECOME PART OF THE CELLULAR "MEMORY" AND CONTRIBUTE TO GENOMIC IMPRINTING. BECAUSE MANY FOOD COMPONENTS BIND TO NRS, THEY CAN ULTIMATELY INFLUENCE TRANSCRIPTION OF GENES ASSOCIATED WITH BIOLOGIC PROCESSES, SUCH AS INFLAMMATION, PROLIFERATION, APOPTOSIS, AND HORMONAL RESPONSE, AND ALTER THE SUSCEPTIBILITY TO CHRONIC DISEASES (E.G., CANCER, DIABETES, OBESITY). THE OBJECTIVE OF THIS REVIEW IS TO HIGHLIGHT HOW NRS INFLUENCE EPIGENETIC REGULATION AND THE RELEVANCE OF DIETARY COMPOUND-NR INTERACTIONS IN HUMAN NUTRITION AND FOR DISEASE PREVENTION AND TREATMENT. IDENTIFYING GENE TARGETS OF UNLIGANDED AND BOUND NRS MAY ASSIST IN THE DEVELOPMENT OF EPIGENETIC MAPS FOR FOOD COMPONENTS AND DIETARY PATTERNS. PROGRESS IN THESE AREAS MAY LEAD TO THE FORMULATION OF DISEASE-PREVENTION MODELS BASED ON EPIGENETIC CONTROL BY INDIVIDUAL OR ASSOCIATIONS OF FOOD LIGANDS OF NRS. 2014 3 5892 56 SYSTEMS GENETICS VIEW OF ENDOMETRIOSIS: A COMMON COMPLEX DISORDER. ENDOMETRIOSIS IS A CONDITION IN WHICH CELLS DERIVED FROM THE ENDOMETRIUM GROW OUTSIDE THE UTERUS, E.G. IN THE PERITONEUM (EXTERNAL GENITAL ENDOMETRIOSIS). AS THESE CELLS ARE UNDER THE INFLUENCE OF FEMALE HORMONES, MAJOR SYMPTOMS OF ENDOMETRIOSIS ARE PAIN, ESPECIALLY DURING THE CYCLE, AND INFERTILITY. NUMEROUS HYPOTHESES FOR THE FORMATION OF ENDOMETRIOSIS CAN BE FOUND IN THE LITERATURE, BUT THERE IS GROWING EVIDENCE OF SERIOUS GENETIC CONTRIBUTIONS TO ENDOMETRIOSIS SUSCEPTIBILITY. THE INVOLVEMENT OF GENES, STEROID HORMONE METABOLISM, IMMUNOLOGICAL REACTIONS, RECEPTOR FORMATION, INFLAMMATION, PROLIFERATION, APOPTOSIS, INTERCELLULAR ADHESION, CELL INVASION AND ANGIOGENESIS AS WELL AS GENES REGULATING THE ACTIVITY OF AFOREMENTIONED ENZYMES HAVE BEEN SUGGESTED. SOME MORE RECENTLY SUGGESTED CANDIDATE GENES PICKED UP IN GENOME-WIDE ASSOCIATION STUDIES ARE INVOLVED IN ONCOGENESIS, METAPLASIA OF ENDOMETRIUM CELLS AND PATHWAYS OF EMBRYONIC DEVELOPMENT OF THE FEMALE REPRODUCTIVE SYSTEM. HOWEVER, GENE MUTATIONS PROVEN TO BE CAUSATIVE FOR ENDOMETRIOSIS HAVE NOT BEEN IDENTIFIED SO FAR, EVEN THOUGH THE ABNORMAL EXPRESSION OF CANDIDATE GENES FOR ENDOMETRIOSIS COULD BE PROVOKED BY DIFFERENT EPIGENETIC MODIFICATIONS INCLUDING DNA METHYLATION, HETEROCHROMATIZATION OR INTRODUCTION OF REGULATORY MIRNA. WE HYPOTHESIZE THAT ENDOMETRIOSIS IS INDUCED BY A COMBINATION OF ABNORMAL GENETIC AND/OR EPIGENETIC MUTATIONS: THE LATTER PAVE THE WAY FOR PATHOLOGICAL CHANGES WHICH BECOME IRREVERSIBLE, AND ACCORDING TO THE "EPIGENETIC LANDSCAPE" THEORY, THIS PROCEEDS TO THE TYPICAL CLINICAL MANIFESTATIONS. TWO STAGES IN THE ENDOMETRIOSIS PATHWAY ARE SUGGESTED: (1) INDUCTION OF PRIMARY ENDOMETRIAL CELLS TOWARD ENDOMETRIOSIS, AND (2) IMPLANTATION AND PROGRESSION OF THESE CELLS INTO ENDOMETRIOSIS LESIONS. THE MODEL FAVORS ENDOMETRIOSIS AS AN OUTGROWTH OF PRIMARY CELLS DIFFERENT IN THEIR ORIGIN, CANALIZATION OF PATHOLOGICAL PROCESSES, MANIFESTATION DIVERSITY PROVOKED BY UNIQUE GENETIC BACKGROUND AND EPIGENETIC INFLUENCES, WHICH RESULT IN MANY DIFFERENT CLINICAL FORMS OF THE DISEASE. 2015 4 1028 46 CIRCULATING MIRNAS RELATED TO EPITHELIAL-MESENCHYMAL TRANSITIONS (EMT) AS THE NEW MOLECULAR MARKERS IN ENDOMETRIOSIS. ENDOMETRIOSIS IS A CHRONIC GYNECOLOGICAL DISEASE DEFINED BY THE PRESENCE OF ENDOMETRIAL-LIKE TISSUE FOUND OUTSIDE THE UTERUS, MOST COMMONLY IN THE PERITONEAL CAVITY. ENDOMETRIOSIS LESIONS ARE HETEROGENOUS BUT USUALLY CONTAIN ENDOMETRIAL STROMAL CELLS AND EPITHELIAL GLANDS, IMMUNE CELL INFILTRATES AND ARE VASCULARIZED AND INNERVATED BY NERVES. THE COMPLEX ETIOPATHOGENESIS AND HETEROGENITY OF THE CLINICAL SYMPTOMS, AS WELL AS THE LACK OF A SPECIFIC NON-INVASIVE DIAGNOSTIC BIOMARKERS, UNDERLINE THE NEED FOR MORE ADVANCED DIAGNOSTIC TOOLS. UNFORTUNATELY, THE CONTRIBUTION OF ENVIRONMENTAL, HORMONAL AND IMMUNOLOGICAL FACTORS IN THE DISEASE ETIOLOGY IS INSUFFICIENT, AND THE CONTRIBUTION OF GENETIC/EPIGENETIC FACTORS IS STILL FRAGMENTARY. THEREFORE, THERE IS A NEED FOR MORE FOCUSED STUDY ON THE MOLECULAR MECHANISMS OF ENDOMETRIOSIS AND NON-INVASIVE DIAGNOSTIC MONITORING SYSTEMS. MICRORNAS (MIRNAS) DEMONSTRATE HIGH STABILITY AND TISSUE SPECIFICITY AND PLAY A SIGNIFICANT ROLE IN MODULATING A RANGE OF MOLECULAR PATHWAYS, AND HENCE MAY BE SUITABLE DIAGNOSTIC BIOMARKERS FOR THE ORIGIN AND DEVELOPMENT OF ENDOMETRIOSIS. OF THESE, THE MOST FREQUENTLY STUDIED ARE THOSE RELATED TO ENDOMETRIOSIS, INCLUDING THOSE INVOLVED IN EPITHELIAL-MESENCHYMAL TRANSITION (EMT), WHOSE EXPRESSION IS ALTERED IN PLASMA OR ENDOMETRIOTIC LESION BIOPSIES; HOWEVER, THE RESULTS ARE AMBIGUOUS. SPECIFIC MIRNAS EXPRESSED IN ENDOMETRIOSIS MAY SERVE AS DIAGNOSTICS MARKERS WITH PROGNOSTIC VALUE, AND THEY HAVE BEEN PROPOSED AS MOLECULAR TARGETS FOR TREATMENT. THE AIM OF THIS REVIEW IS TO PRESENT SELECTED MIRNAS ASSOCIATED WITH EMT KNOWN TO HAVE EXPERIMENTALLY CONFIRMED SIGNIFICANCE, AND DISCUSS THEIR UTILITY AS BIOMARKERS IN ENDOMETRIOSIS. 2021 5 3003 56 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 6 3005 43 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 7 1202 46 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 5378 31 RECENT INSIGHTS ON THE GENETICS AND EPIGENETICS OF ENDOMETRIOSIS. ENDOMETRIOSIS IS A GYNECOLOGIC DISEASE AFFECTING UP TO 10% OF THE WOMEN AND A MAJOR CAUSE OF PAIN AND INFERTILITY. IT IS CHARACTERIZED BY THE IMPLANTATION OF FUNCTIONAL ENDOMETRIAL TISSUE AT ECTOPIC POSITIONS GENERALLY WITHIN THE PERITONEUM. THIS COMPLEX DISEASE HAS AN IMPORTANT GENETIC COMPONENT WITH A HERITABILITY ESTIMATED AT AROUND 50%. THIS REVIEW AIMS AT PROVIDING RECENT INSIGHTS INTO THE GENETIC BASES OF ENDOMETRIOSIS, AND PRESENTS A DETAILED OVERVIEW OF EVIDENCE OF EPIGENETIC ALTERATIONS SPECIFIC TO THIS DISEASE. IN THE FUTURE, THESE ALTERATIONS MAY CONSTITUTE THERAPEUTIC TARGETS FOR PHARMACOLOGICAL COMPOUNDS ABLE TO MODIFY THE EPIGENETIC CODE. 2017 9 4310 40 MICRORNAS AND PROGESTERONE RECEPTOR SIGNALING IN ENDOMETRIOSIS PATHOPHYSIOLOGY. ENDOMETRIOSIS IS A SIGNIFICANT DISEASE CHARACTERIZED BY INFERTILITY AND PELVIC PAIN IN WHICH ENDOMETRIAL STROMAL AND GLANDULAR TISSUE GROW IN ECTOPIC LOCATIONS. ALTERED RESPONSIVENESS TO PROGESTERONE IS A CONTRIBUTING FACTOR TO ENDOMETRIOSIS PATHOPHYSIOLOGY, BUT THE PRECISE MECHANISMS ARE POORLY UNDERSTOOD. PROGESTERONE RESISTANCE INFLUENCES BOTH THE EUTOPIC AND ECTOPIC (ENDOMETRIOTIC LESION) ENDOMETRIUM. AN INABILITY OF THE EUTOPIC ENDOMETRIUM TO PROPERLY RESPOND TO PROGESTERONE IS BELIEVED TO CONTRIBUTE TO THE INFERTILITY ASSOCIATED WITH THE DISEASE, WHILE AN ALTERED RESPONSIVENESS OF ENDOMETRIOTIC LESION TISSUE MAY CONTRIBUTE TO THE SURVIVAL OF THE ECTOPIC TISSUE AND ASSOCIATED SYMPTOMS. WOMEN WITH ENDOMETRIOSIS EXPRESS ALTERED LEVELS OF SEVERAL ENDOMETRIAL PROGESTERONE TARGET GENES WHICH MAY BE DUE TO THE ABNORMAL EXPRESSION AND/OR FUNCTION OF PROGESTERONE RECEPTORS AND/OR CHAPERONE PROTEINS, AS WELL AS INFLAMMATION, GENETICS, AND EPIGENETICS. MIRNAS ARE A CLASS OF EPIGENETIC MODULATORS PROPOSED TO PLAY A ROLE IN ENDOMETRIOSIS PATHOPHYSIOLOGY, INCLUDING THE MODULATION OF PROGESTERONE SIGNALING. IN THIS PAPER, WE SUMMARIZE THE ROLE OF PROGESTERONE RECEPTORS AND PROGESTERONE SIGNALING IN ENDOMETRIOSIS PATHOPHYSIOLOGY, REVIEW MIRNAS, WHICH ARE OVER-EXPRESSED IN ENDOMETRIOSIS TISSUES AND FLUIDS, AND FOLLOW THIS WITH A DISCUSSION ON THE POTENTIAL REGULATION OF KEY PROGESTERONE SIGNALING COMPONENTS BY THESE MIRNAS, CONCLUDING WITH SUGGESTIONS FOR FUTURE RESEARCH ENDEAVORS IN THIS AREA. 2022 10 4129 28 MECHANISMS OF ENDOMETRIAL PROGESTERONE RESISTANCE. THROUGHOUT THE REPRODUCTIVE YEARS, THE RISE AND FALL IN OVARIAN HORMONES ELICIT IN THE ENDOMETRIUM WAVES OF CELL PROLIFERATION, DIFFERENTIATION, RECRUITMENT OF INFLAMMATORY CELLS, APOPTOSIS, TISSUE BREAKDOWN AND REGENERATION. THE ACTIVATED PROGESTERONE RECEPTOR, A MEMBER OF THE SUPERFAMILY OF LIGAND-DEPENDENT TRANSCRIPTION FACTORS, IS THE MASTER REGULATOR OF THIS INTENSE TISSUE REMODELLING PROCESS IN THE UTERUS. ITS ACTIVITY IS TIGHTLY REGULATED BY INTERACTION WITH CELL-SPECIFIC TRANSCRIPTION FACTORS AND COREGULATORS AS WELL AS BY SPECIFIC POSTTRANSLATIONAL MODIFICATIONS THAT RESPOND DYNAMICALLY TO A VARIETY OF ENVIRONMENTAL AND INFLAMMATORY SIGNALS. ENDOMETRIOSIS, A CHRONIC INFLAMMATORY DISORDER, DISRUPTS COORDINATED PROGESTERONE RESPONSES THROUGHOUT THE REPRODUCTIVE TRACT, INCLUDING IN THE ENDOMETRIUM. THIS PHENOMENON IS INCREASINGLY REFERRED TO AS 'PROGESTERONE RESISTANCE'. EMERGING EVIDENCE SUGGESTS THAT PROGESTERONE RESISTANCE IN ENDOMETRIOSIS IS NOT JUST A CONSEQUENCE OF PERTURBED PROGESTERONE SIGNAL TRANSDUCTION CAUSED BY CHRONIC INFLAMMATION BUT ASSOCIATED WITH EPIGENETIC CHROMATIN CHANGES THAT DETERMINE THE INTRINSIC RESPONSIVENESS OF ENDOMETRIAL CELLS TO DIFFERENTIATION CUES. 2012 11 2275 48 EPIGENETIC REGULATION AND T-CELL RESPONSES IN ENDOMETRIOSIS - SOMETHING OTHER THAN AUTOIMMUNITY. ENDOMETRIOSIS IS DEFINED AS THE PRESENCE OF ENDOMETRIAL-LIKE GLANDS AND STROMA LOCATED OUTSIDE THE UTERINE CAVITY. THIS COMMON, ESTROGEN DEPENDENT, INFLAMMATORY CONDITION AFFECTS UP TO 15% OF REPRODUCTIVE-AGED WOMEN AND IS A WELL-RECOGNIZED CAUSE OF CHRONIC PELVIC PAIN AND INFERTILITY. DESPITE THE STILL UNKNOWN ETIOLOGY OF ENDOMETRIOSIS, MUCH EVIDENCE SUGGESTS THE PARTICIPATION OF EPIGENETIC MECHANISMS IN THE DISEASE ETIOPATHOGENESIS. THE MAIN RATIONALE IS BASED ON THE FACT THAT HERITABLE PHENOTYPE CHANGES THAT DO NOT INVOLVE ALTERATIONS IN THE DNA SEQUENCE ARE COMMON TRIGGERS FOR HORMONAL, IMMUNOLOGICAL, AND INFLAMMATORY DISORDERS, WHICH PLAY A KEY ROLE IN THE FORMATION OF ENDOMETRIOTIC FOCI. EPIGENETIC MECHANISMS REGULATING T-CELL RESPONSES, INCLUDING DNA METHYLATION AND POSTTRANSLATIONAL HISTONE MODIFICATIONS, DESERVE ATTENTION BECAUSE TISSUE-RESIDENT T LYMPHOCYTES WORK IN CONCERT WITH ORGAN STRUCTURAL CELLS TO GENERATE APPROPRIATE IMMUNE RESPONSES AND ARE FUNCTIONALLY SHAPED BY ORGAN-SPECIFIC ENVIRONMENTAL CONDITIONS. THUS, A FAILURE TO PRECISELY REGULATE IMMUNE CELL TRANSCRIPTION MAY RESULT IN COMPROMISED IMMUNOLOGICAL INTEGRITY OF THE ORGAN WITH AN INCREASED RISK OF INFLAMMATORY DISORDERS. THE COEXISTENCE OF ENDOMETRIOSIS AND AUTOIMMUNITY IS A WELL-KNOWN OCCURRENCE. RECENT RESEARCH RESULTS INDICATE REGULATORY T-CELL (TREG) ALTERATIONS IN ENDOMETRIOSIS, AND AN INCREASED NUMBER OF HIGHLY ACTIVE TREGS AND MACROPHAGES HAVE BEEN FOUND IN PERITONEAL FLUID FROM WOMEN WITH ENDOMETRIOSIS. ELIMINATION OF THE REGULATORY FUNCTION OF T CELLS AND AN IMBALANCE BETWEEN T HELPER CELLS OF THE TH1 AND TH2 TYPES HAVE BEEN REPORTED IN THE ENDOMETRIA OF WOMEN WITH ENDOMETRIOSIS-ASSOCIATED INFERTILITY. THIS REVIEW AIMS TO PRESENT THE STATE OF THE ART IN RECOGNITION EPIGENETIC REPROGRAMMING OF T CELLS AS THE KEY FACTOR IN THE PATHOPHYSIOLOGY OF ENDOMETRIOSIS IN THE CONTEXT OF T-CELL-RELATED AUTOIMMUNITY. THE NEW POTENTIAL THERAPEUTIC APPROACHES BASED ON EPIGENETIC MODULATION AND/OR ADOPTIVE TRANSFER OF T CELLS WILL ALSO BE OUTLINED. 2022 12 6796 40 [ENDOMETRIOSIS: A NEW APPROACH TO ETIOLOGY AND PATHOGENESIS (REVIEW)]. ENDOMETRIOSIS IS A DYSHORMONAL IMMUNE-DEPENDENT GENETICALLY DETERMINED DISEASE, WHICH APPEARS AS AN ENDOMETRIOID TISSUE THAT GROWS OUTSIDE THE UTERINE. ENDOMETRIOSIS IS ONE OF THE MOST URGENT PROBLEMS OF MEDICINE. TO DATE, NEW CONCEPTS OF THE ENDOMETRIOSIS ETIOLOGY AND PATHOGENESIS HAVE BEEN DEVELOPED, BUT, DESPITE THEIR ABUNDANCE, THERE IS NO UNIFIED THEORY. GENETIC AND EPIGENETIC FACTORS RESULT IN CHANGES IN AN EXPRESSION OF AROMATASE, STEROIDOGENIC FACTOR 1, AND ESTROGEN RECEPTORS ARE SUGGESTED TO BE THE MAIN CAUSE OF ENDOMETRIOSIS. THESE CHANGES LEAD TO AN ACTIVE SYNTHESIS OF VARIOUS PRO-INFLAMMATORY AGENTS AND A NERVE GROWTH FACTOR, THAT ARE IMPORTANT IN THE DEVELOPMENT OF PAIN SYNDROME. ALSO, CHANGES IN THE PROGESTERONE RECEPTOR FUNCTIONING AND THE LOCAL PROGESTERONE RESISTANCE DEVELOPMENT DECREASE THE ANTIPROLIFERATIVE ACTIVITY, APOPTOSIS, AND THE ANTI-INFLAMMATORY SUBSTANCES LEVEL, AS WELL AS INCREASE THE PROSTAGLANDIN, METALLOPROTEINASE ACTIVITY, AND LEVEL OF HYPOXIA FACTORS. IN ADDITION, THERE ARE SHREDS OF EVIDENCE THAT ENDOMETRIOSIS IS ASSOCIATED WITH THE RISK OF MALIGNANT TUMORS DEVELOPMENT, SO NEW CONCEPTS FOR UNDERSTANDING THESE MECHANISMS ARE ACTIVELY DEVELOPING. SOME OF THESE MECHANISMS ARE DISCUSSED IN THIS REVIEW. 2017 13 2086 42 EPIGENETIC DYSREGULATION IN ENDOMETRIOSIS: IMPLICATIONS FOR PATHOPHYSIOLOGY AND THERAPEUTICS. ENDOMETRIOSIS IS A PREVALENT GYNECOLOGICAL CONDITION ASSOCIATED WITH PELVIC PAIN AND INFERTILITY. DESPITE MORE THAN A CENTURY OF RESEARCH, THE ETIOLOGY OF ENDOMETRIOSIS STILL ELUDES SCIENTIFIC CONSENSUS. THIS LACK OF CLARITY HAS RESULTED IN SUBOPTIMAL PREVENTION, DIAGNOSIS, AND TREATMENT OPTIONS. EVIDENCE OF GENETIC CONTRIBUTORS TO ENDOMETRIOSIS IS INTERESTING BUT LIMITED; HOWEVER, SIGNIFICANT PROGRESS HAS BEEN MADE IN RECENT YEARS IN IDENTIFYING EPIGENETIC ROLE IN THE PATHOGENESIS OF ENDOMETRIOSIS THROUGH CLINICAL STUDIES, IN VITRO CELL CULTURE EXPERIMENTS, AND IN VIVO ANIMAL MODELS. THE PREDOMINANT FINDINGS INCLUDE ENDOMETRIOSIS-RELATED DIFFERENTIAL EXPRESSION OF DNA METHYLTRANSFERASES AND DEMETHYLASES, HISTONE DEACETYLASES, METHYLTRANSFERASES, AND DEMETHYLASES, AND REGULATORS OF CHROMATIN ARCHITECTURE. THERE IS ALSO AN EMERGING ROLE FOR MIRNAS IN THE CONTROL OF EPIGENETIC REGULATORS IN THE ENDOMETRIUM AND ENDOMETRIOSIS. CHANGES IN THESE EPIGENETIC REGULATORS RESULT IN DIFFERENTIAL CHROMATIN ORGANIZATION AND DNA METHYLATION WITH CONSEQUENCES FOR GENE EXPRESSION INDEPENDENT OF A GENETIC SEQUENCE. EPIGENETICALLY ALTERED EXPRESSION OF GENES RELATED TO STEROID HORMONE PRODUCTION AND SIGNALING, IMMUNE REGULATION, AND ENDOMETRIAL CELL IDENTITY AND FUNCTION HAVE ALL BEEN IDENTIFIED AND APPEAR TO PLAY INTO THE PATHOPHYSIOLOGICAL MECHANISMS OF ENDOMETRIOSIS AS WELL AS RESULTING INFERTILITY. THIS REVIEW SUMMARIZES AND CRITICALLY DISCUSSES EARLY SEMINAL FINDINGS, THE EVER-GROWING RECENT EVIDENCE OF EPIGENETIC CONTRIBUTIONS TO THE PATHOPHYSIOLOGY OF ENDOMETRIOSIS, AND IMPLICATIONS FOR PROPOSED EPIGENETICALLY TARGETED THERAPEUTICS. 2023 14 4435 47 MOLECULAR DYSREGULATIONS UNDERLYING THE PATHOGENESIS OF ENDOMETRIOSIS. ENDOMETRIOSIS IS A CRIPPLING DISEASE CHARACTERIZED BY THE PRESENCE OF ENDOMETRIUM-LIKE TISSUE OR SCAR OUTSIDE THE UTERINE CAVITY, COMMONLY CONFINED TO THE PERITONEAL AND SEROSAL SURFACES OF THE PELVIC ORGANS. 10-15% OF WOMEN IN REPRODUCTIVE AGE ARE ESTIMATED TO BE AFFECTED BY ENDOMETRIOSIS. MOST OF THESE PATIENTS PRESENT WITH INFERTILITY AND SUFFER FROM PELVIC PAIN. THE BENIGN DISEASE RARELY PROGRESSES TO MALIGNANCY. REGARDLESS OF ITS HIGH PREVALENCE, THE PATHOGENESIS OF THE DISEASE IS NOT FULLY UNDERSTOOD. TREATMENT OPTIONS FOR ENDOMETRIOSIS ARE LIMITED AND ARE OFTEN BASED ON A SYMPTOMATIC APPROACH. THE UNAVAILABILITY OF PROPER DIAGNOSTIC APPROACHES, FEWER THERAPEUTIC OPTIONS, AND SPARSE UNDERSTANDING OF MOLECULAR ALTERATIONS ARE RESPONSIBLE FOR THE CONTINUED DISEASE BURDEN. EXPLORING THE MOLECULAR ELEMENTS CAUSING THE PATHOGENESIS OF ENDOMETRIOSIS MAY LEAD TO A NUMBER OF BREAKTHROUGHS IN THE TREATMENT OF THE ILLNESS, SUCH AS THE DISCOVERY OF NEW BIOMARKERS FOR DIAGNOSIS AND THERAPEUTIC TARGETS THAT CAN BE A GUIDE TO BETTER PROGNOSIS AND REDUCED RECURRENCE. THE GOAL OF THIS REVIEW IS TO PROVIDE THE READER A CRITICAL UNDERSTANDING OF THE DISEASE BY SUMMARIZING THE GENETIC, IMMUNOLOGICAL, HORMONAL, AND EPIGENETIC DEREGULATIONS THAT SUPPORT THE MOLECULAR BASIS FOR DEVELOPMENT OF ENDOMETRIOTIC CYST, WITH A SPECIAL FOCUS ON THE STUDY MODELS NEEDED TO ANALYZE THESE CHANGES IN THE ENDOMETRIOTIC MICROENVIRONMENT. 2021 15 1893 51 ENDOMETRIOSIS: NEW PERSPECTIVE FOR THE DIAGNOSIS OF CERTAIN CYTOKINES IN WOMEN AND ADOLESCENT GIRLS, AS WELL AS THE PROGRESSION OF DISEASE OUTGROWTH: A SYSTEMATIC REVIEW. ENDOMETRIOSIS IS A COMMON CHRONIC GYNECOLOGICAL DISORDER THAT UNDOUBTEDLY IMPACTS ON QUALITY OF LIFE, AND IS ONE OF THE MORE COMPLEX AND MYSTERIOUS ILLNESSES OF OUR CENTURY, WHICH IS ASSOCIATED WITH THE IMPROPER GROWTH OF ENDOMETRIAL TISSUE OUTSIDE OF THE UTERINE CAVITY. THIS PATHOLOGICALLY IMPLANTED TISSUE CAN BE FOUND MOST FREQUENTLY IN THE MINOR PELVIS, BUT ALSO IN THE PERITONEAL CAVITY, AND CAN AFFECT MANY ORGANS, LEADING TO CHRONIC PELVIC PAIN SYNDROME, INFERTILITY, AND DYSMENORRHEA. ENDOMETRIAL TISSUE IS A PARTICULARLY DYNAMIC TISSUE THAT HAS A DIRECT IMPACT ON THE PROGRESSION OF THE DISEASE, WITH ALTERED IMMUNITY, AS WELL AS CYTOKINE STORMS WITHIN THE METAPLASTIC ENDOMETRIOTIC SITE, AS POSSIBLE KEY FACTORS. CURRENTLY, DIAGNOSIS OF THIS MYSTERIOUS CHRONIC ILLNESS RELIES ON PERFORMING A LAPAROSCOPIC PROCEDURE WITH TISSUE SAMPLING. ONE OF THE MOST TROUBLESOME OUTCOMES OF THIS UNINTENDED PROGRESSION IS THAT WE LACK ANY SPECIFIC, SENSITIVE, NON-INVASIVE DIAGNOSTIC TOOLS. CURRENTLY, THE VAST MAJORITY OF REGIME STEWARDSHIP OPTIONS RELY ON ANTI-CONTRACEPTIVE DRUGS, OR OTHER REMEDIES THAT SUPPRESS THE RELEASE OF ESTROGEN THROUGH THE GONADS-ALTHOUGH IN MOST CLINICAL TRIALS, ENDOMETRIOSIS IS A CHRONIC PROGRESSIVE DISORDER THAT DEPENDS MOSTLY ON THE HIGH CONCENTRATION OF ESTROGEN. MOREOVER, MANY SPECIFIC TRIALS HAVE DEMONSTRATED THAT THE EUTOPIC ENDOMETRIAL CELLS IN INDIVIDUALS WITH ENDOMETRIOSIS REMAIN MUCH MORE RESISTANT TO THE IMMUNOLOGICAL ANNIHILATION PROCESS CAUSED BY CERTAIN ELEMENTS OF THE IMMUNE SYSTEM. NEVERTHELESS, EUTOPIC ENDOMETRIAL CELLS HAVE THE POTENTIAL TO SIMILARLY ESCALATE THE EXPRESSION OF AROMATASE RECEPTORS ON THE SURFACE OF THE PATHOLOGICAL CELLS, WHICH IN THE FINAL CASCADE CAUSE AN INCREASE IN THE CONCENTRATION OF ESTROGEN, AS WELL AS OTHER INFLAMMATORY PROTEINS THAT CONTRIBUTE TO PATHOLOGICAL OUTGROWTH. DATA REVEAL OCCURRENCE AMONG FIRST-DEGREE RELATIVES, SUGGESTING THAT THE SPECIFIC CASCADE COULD BE RELATED TO INHERITED AS WELL AS EPIGENETIC (ACQUIRED) MECHANISMS. IN WOMEN WITH THE DISEASE, CONFIRMED BY LAPAROSCOPIC PROCEDURES, DIAGNOSIS OF ENDOMETRIOSIS CAN BE ESTABLISHED ALSO VIA DETECTION BY GENE POLYMORPHISM IN THE GENES WHICH ARE RESPONSIBLE FOR RESPONSIBLE FOR THE DETOXIFICATION PHASE OF ESTROGEN RECEPTORS AND OTHER IMMUNOMODULATOR COMPONENTS. A RECENT PUBLICATION AIMS TO REVEAL A NEW PROSPECT FOR THE NON-INVASIVE DIAGNOSIS, DETECTION, AND ESTIMATION OF CERTAIN BIOMARKERS FOR MUCH MORE SPECIFIC INVESTIGATION OF THE DISEASE'S PROGRESSION. 2021 16 2668 43 ESTROGEN RECEPTORS AND ENDOMETRIOSIS. ENDOMETRIOSIS IS A FREQUENT AND CHRONIC INFLAMMATORY DISEASE WITH IMPACTS ON REPRODUCTION, HEALTH AND QUALITY OF LIFE. THIS DISORDER IS HIGHLY ESTROGEN-DEPENDENT AND THE PURPOSE OF HORMONAL TREATMENTS IS TO DECREASE THE ENDOGENOUS OVARIAN PRODUCTION OF ESTROGENS. HIGH ESTROGEN PRODUCTION IS A CONSISTENTLY OBSERVED ENDOCRINE FEATURE OF ENDOMETRIOSIS. MRNA AND PROTEIN LEVELS OF ESTROGEN RECEPTORS (ER) ARE DIFFERENT BETWEEN A NORMAL HEALTHY ENDOMETRIUM AND ECTOPIC/EUTOPIC ENDOMETRIAL LESIONS: ENDOMETRIOTIC STROMAL CELLS EXPRESS EXTRAORDINARILY HIGHER ERBETA AND SIGNIFICANTLY LOWER ERALPHA LEVELS COMPARED WITH ENDOMETRIAL STROMAL CELLS. ABERRANT EPIGENETIC REGULATION SUCH AS DNA METHYLATION IN ENDOMETRIOTIC CELLS IS ASSOCIATED WITH THE PATHOGENESIS AND DEVELOPMENT OF ENDOMETRIOSIS. ALTHOUGH THERE IS A LARGE BODY OF DATA REGARDING ERS IN ENDOMETRIOSIS, OUR UNDERSTANDING OF THE ROLES OF ERALPHA AND ERBETA IN THE PATHOGENESIS OF ENDOMETRIOSIS REMAINS INCOMPLETE. THE GOAL OF THIS REVIEW IS TO PROVIDE AN OVERVIEW OF THE LINKS BETWEEN ENDOMETRIOSIS, ERS AND THE RECENT ADVANCES OF TREATMENT STRATEGIES BASED ON ERS MODULATION. WE WILL ALSO ATTEMPT TO SUMMARIZE THE CURRENT UNDERSTANDING OF THE MOLECULAR AND CELLULAR MECHANISMS OF ACTION OF ERS AND HOW THIS COULD PAVE THE WAY TO NEW THERAPEUTIC STRATEGIES. 2020 17 4957 41 PATHOGENESIS OF ENDOMETRIOSIS: THE GENETIC/EPIGENETIC THEORY. OBJECTIVE: TO STUDY THE PATHOPHYSIOLOGY OF ENDOMETRIOSIS. DESIGN: OVERVIEW OF OBSERVATIONS ON ENDOMETRIOSIS. SETTING: NOT APPLICABLE. PATIENT(S): NONE. INTERVENTIONS(S): NONE. MAIN OUTCOME MEASURE(S): THE HYPOTHESIS IS COMPATIBLE WITH ALL OBSERVATIONS. RESULT(S): ENDOMETRIOSIS, ENDOMETRIUM-LIKE TISSUE OUTSIDE THE UTERUS, HAS A VARIABLE MACROSCOPIC APPEARANCE AND A POORLY UNDERSTOOD NATURAL HISTORY. IT IS A HEREDITARY AND HETEROGENEOUS DISEASE WITH MANY BIOCHEMICAL CHANGES IN THE LESIONS, WHICH ARE CLONAL IN ORIGIN. IT IS ASSOCIATED WITH PAIN, INFERTILITY, ADENOMYOSIS, AND CHANGES IN THE JUNCTIONAL ZONE, PLACENTATION, IMMUNOLOGY, PLASMA, PERITONEAL FLUID, AND CHRONIC INFLAMMATION OF THE PERITONEAL CAVITY. THE SAMPSON HYPOTHESIS OF IMPLANTED ENDOMETRIAL CELLS FOLLOWING RETROGRADE MENSTRUATION, ANGIOGENIC SPREAD, LYMPHOGENIC SPREAD, OR THE METAPLASIA THEORY CANNOT EXPLAIN ALL OBSERVATIONS IF METAPLASIA IS DEFINED AS CELLS WITH REVERSIBLE CHANGES AND AN ABNORMAL BEHAVIOR/MORPHOLOGY DUE TO THE ABNORMAL ENVIRONMENT. WE PROPOSE A POLYGENETIC/POLYEPIGENETIC MECHANISM. THE SET OF GENETIC AND EPIGENETIC INCIDENTS TRANSMITTED AT BIRTH COULD EXPLAIN THE HEREDITARY ASPECTS, THE PREDISPOSITION, AND THE ENDOMETRIOSIS-ASSOCIATED CHANGES IN THE ENDOMETRIUM, IMMUNOLOGY, AND PLACENTATION. TO DEVELOP TYPICAL, CYSTIC OVARIAN OR DEEP ENDOMETRIOSIS LESIONS, A VARIABLE SERIES OF ADDITIONAL TRANSMISSIBLE GENETIC AND EPIGENETIC INCIDENTS ARE REQUIRED TO OCCUR IN A CELL WHICH MAY VARY FROM ENDOMETRIAL TO STEM CELLS. SUBTLE LESIONS ARE VIEWED AS ENDOMETRIUM IN A DIFFERENT ENVIRONMENT UNTIL ADDITIONAL INCIDENTS OCCUR. TYPICAL CYSTIC OVARIAN OR DEEP ENDOMETRIOSIS LESIONS ARE HETEROGENEOUS AND REPRESENT THREE DIFFERENT DISEASES. CONCLUSION(S): THE GENETIC EPIGENETIC THEORY IS COMPATIBLE WITH ALL OBSERVATIONS ON ENDOMETRIOSIS. IMPLICATIONS FOR TREATMENT AND PREVENTION ARE DISCUSSED. 2019 18 1889 40 ENDOMETRIOSIS MALIGNANT TRANSFORMATION: EPIGENETICS AS A PROBABLE MECHANISM IN OVARIAN TUMORIGENESIS. ENDOMETRIOSIS, DEFINED AS THE PRESENCE OF ECTOPIC ENDOMETRIAL GLANDS AND STROMA OUTSIDE THE UTERINE CAVITY, IS A CHRONIC, HORMONE-DEPENDENT GYNECOLOGIC DISEASE AFFECTING MILLIONS OF WOMEN ACROSS THE WORLD, WITH SYMPTOMS INCLUDING CHRONIC PELVIC PAIN, DYSMENORRHEA, DYSPAREUNIA, DYSURIA, AND SUBFERTILITY. IN ADDITION, THERE IS WELL-ESTABLISHED EVIDENCE THAT, ALTHOUGH ENDOMETRIOSIS IS CONSIDERED BENIGN, IT IS ASSOCIATED WITH AN INCREASED RISK OF MALIGNANT TRANSFORMATION, WITH THE INVOLVEMENT OF VARIOUS MECHANISMS OF DEVELOPMENT. MORE AND MORE EVIDENCE REVEALS AN IMPORTANT CONTRIBUTION OF EPIGENETIC MODIFICATION NOT ONLY IN ENDOMETRIOSIS BUT ALSO IN MECHANISMS OF ENDOMETRIOSIS MALIGNANT TRANSFORMATION, INCLUDING DNA METHYLATION AND DEMETHYLATION, HISTONE MODIFICATIONS, AND MIRNA ABERRANT EXPRESSIONS. IN THIS PRESENT REVIEW, WE MAINLY SUMMARIZE THE RESEARCH PROGRESS ABOUT THE CURRENT KNOWLEDGE REGARDING THE EPIGENETIC MODIFICATIONS OF THE RELATIONS BETWEEN ENDOMETRIOSIS MALIGNANT TRANSFORMATION AND OVARIAN CANCER IN AN EFFORT TO IDENTIFY SOME RISK FACTORS PROBABLY ASSOCIATED WITH ECTOPIC ENDOMETRIUM TRANSFORMATION. 2018 19 1891 43 ENDOMETRIOSIS. PELVIC ENDOMETRIOSIS IS A COMPLEX SYNDROME CHARACTERIZED BY AN ESTROGEN-DEPENDENT CHRONIC INFLAMMATORY PROCESS THAT AFFECTS PRIMARILY PELVIC TISSUES, INCLUDING THE OVARIES. IT IS CAUSED WHEN SHED ENDOMETRIAL TISSUE TRAVELS RETROGRADE INTO THE LOWER ABDOMINAL CAVITY. ENDOMETRIOSIS IS THE MOST COMMON CAUSE OF CHRONIC PELVIC PAIN IN WOMEN AND IS ASSOCIATED WITH INFERTILITY. THE UNDERLYING PATHOLOGIC MECHANISMS IN THE INTRACAVITARY ENDOMETRIUM AND EXTRAUTERINE ENDOMETRIOTIC TISSUE INVOLVE DEFECTIVELY PROGRAMMED ENDOMETRIAL MESENCHYMAL PROGENITOR/STEM CELLS. ALTHOUGH ENDOMETRIOTIC STROMAL CELLS, WHICH COMPOSE THE BULK OF ENDOMETRIOTIC LESIONS, DO NOT CARRY SOMATIC MUTATIONS, THEY DEMONSTRATE SPECIFIC EPIGENETIC ABNORMALITIES THAT ALTER EXPRESSION OF KEY TRANSCRIPTION FACTORS. FOR EXAMPLE, GATA-BINDING FACTOR-6 OVEREXPRESSION TRANSFORMS AN ENDOMETRIAL STROMAL CELL TO AN ENDOMETRIOTIC PHENOTYPE, AND STEROIDOGENIC FACTOR-1 OVEREXPRESSION CAUSES EXCESSIVE PRODUCTION OF ESTROGEN, WHICH DRIVES INFLAMMATION VIA PATHOLOGICALLY HIGH LEVELS OF ESTROGEN RECEPTOR-BETA. PROGESTERONE RECEPTOR DEFICIENCY CAUSES PROGESTERONE RESISTANCE. POPULATIONS OF ENDOMETRIAL AND ENDOMETRIOTIC EPITHELIAL CELLS ALSO HARBOR MULTIPLE CANCER DRIVER MUTATIONS, SUCH AS KRAS, WHICH MAY BE ASSOCIATED WITH THE ESTABLISHMENT OF PELVIC ENDOMETRIOSIS OR OVARIAN CANCER. IT IS NOT KNOWN HOW INTERACTIONS BETWEEN EPIGENOMICALLY DEFECTIVE STROMAL CELLS AND THE MUTATED GENES IN EPITHELIAL CELLS CONTRIBUTE TO THE PATHOGENESIS OF ENDOMETRIOSIS. ENDOMETRIOSIS-ASSOCIATED PELVIC PAIN IS MANAGED BY SUPPRESSION OF OVULATORY MENSES AND ESTROGEN PRODUCTION, CYCLOOXYGENASE INHIBITORS, AND SURGICAL REMOVAL OF PELVIC LESIONS, AND IN VITRO FERTILIZATION IS FREQUENTLY USED TO OVERCOME INFERTILITY. ALTHOUGH NOVEL TARGETED TREATMENTS ARE BECOMING AVAILABLE, AS ENDOMETRIOSIS PATHOPHYSIOLOGY IS BETTER UNDERSTOOD, PREVENTIVE APPROACHES SUCH AS LONG-TERM OVULATION SUPPRESSION MAY PLAY A CRITICAL ROLE IN THE FUTURE. 2019 20 2575 38 EPIGENETICS OF ESTROGEN AND PROGESTERONE RECEPTORS IN ENDOMETRIOSIS. ENDOMETRIOSIS IS AN ESTROGEN-DEPENDENT INFLAMMATORY GYNECOLOGICAL DISEASE. INCREASED ESTROGEN ACTIVITY AND PROGESTERONE RESISTANCE ARE THE MAIN HORMONAL SUBSTRATE OF THIS DISEASE AND ARE ASSOCIATED WITH INFLAMMATORY RESPONSE AND DEBILITATING SYMPTOMS, INCLUDING PAIN AND INFERTILITY. ESTROGENS AND PROGESTERONE ACT VIA THEIR SPECIFIC NUCLEAR RECEPTORS. THE REGULATION OF RECEPTOR EXPRESSION BY EPIGENETICS MAYBE A CRITICAL FACTOR FOR ENDOMETRIOSIS. THE PRESENT REVIEW AIMS TO DISCUSS THE EPIGENETIC MECHANISMS RELATED TO THE EXPRESSION OF ESTROGEN RECEPTORS (ERS) AND PROGESTERONE RECEPTORS (PRS) IN PATIENTS WITH ENDOMETRIOSIS, INCLUDING TWO CLASSIC EPIGENETIC MECHANISMS: DNA METHYLATION AND HISTONE MODIFICATION, AND, OTHER NON-CLASSIC MECHANISMS: MIRNAS AND LNCRNA. SEVERAL IN VITRO AND IN VIVO STUDIES SUPPORT THE KEY ROLE OF EPIGENETICS IN THE REGULATION OF THE EXPRESSION OF ERS AND PRS, WHICH MAY PROVIDE NEW MOLECULES AND TARGETS FOR THE DIAGNOSIS AND TREATMENT OF ENDOMETRIOSIS. 2020