1 111 161 A ROLE FOR G-PROTEIN COUPLED ESTROGEN RECEPTOR (GPER) IN ESTROGEN-INDUCED CARCINOGENESIS: DYSREGULATED GLANDULAR HOMEOSTASIS, SURVIVAL AND METASTASIS. MECHANISMS OF CARCINOGENESIS BY ESTROGEN CENTER ON ITS MITOGENIC AND GENOTOXIC POTENTIAL ON TUMOR TARGET CELLS. THESE MODELS SUGGEST THAT ESTROGEN RECEPTOR (ER) SIGNALING PROMOTES EXPANSION OF THE TRANSFORMED POPULATION AND THAT SUBSEQUENT ACCUMULATION OF SOMATIC MUTATIONS THAT DRIVE CANCER PROGRESSION OCCUR VIA METABOLIC ACTIVATION OF CATHECOL ESTROGENS OR BY EPIGENETIC MECHANISMS. RECENT FINDINGS THAT GPER IS LINKED TO OBESITY, VASCULAR PATHOLOGY AND IMMUNOSUPPRESSION, KEY EVENTS IN THE DEVELOPMENT OF METABOLIC SYNDROME AND INTRA-TISSULAR ESTROGEN SYNTHESIS, PROVIDES AN ALTERNATE VIEW OF ESTROGEN-INDUCED CARCINOGENESIS. CONSISTENT WITH THIS CONCEPT, GPER IS DIRECTLY ASSOCIATED WITH CLINICOPATHOLOGICAL INDICES THAT PREDICT CANCER PROGRESSION AND POOR SURVIVAL IN BREAST AND GYNECOLOGICAL CANCERS. MOREOVER, GPER MANIFESTS CELL BIOLOGICAL RESPONSES AND A MICROENVIRONMENT CONDUCIVE FOR TUMOR DEVELOPMENT AND CANCER PROGRESSION, REGULATING CELLULAR RESPONSES ASSOCIATED WITH GLANDULAR HOMEOSTASIS AND SURVIVAL, INVADING SURROUNDING TISSUE AND ATTRACTING A VASCULAR SUPPLY. THUS, THE CELLULAR ACTIONS ATTRIBUTED TO GPER FIT WELL WITH THE KNOWN MOLECULAR MECHANISMS OF G-PROTEIN COUPLED RECEPTORS, GPCRS, NAMELY, THEIR ABILITY TO TRANSACTIVATE INTEGRINS AND EGF RECEPTORS AND ALTER THE INTERACTION BETWEEN GLANDULAR EPITHELIA AND THEIR EXTRACELLULAR ENVIRONMENT, AFFECTING EPITHELIAL-TO-MESENCHYMAL TRANSITION (EMT) AND ALLOWING FOR TUMOR CELL SURVIVAL AND DISSEMINATION. THIS PERSPECTIVE REVIEWS THE MOLECULAR AND CELLULAR RESPONSES MANIFESTED BY GPER AND EVALUATES ITS CONTRIBUTION TO FEMALE REPRODUCTIVE CANCERS AS DISEASES THAT PROGRESS AS A RESULT OF DYSREGULATED GLANDULAR HOMEOSTASIS RESULTING IN CHRONIC INFLAMMATION AND METASTASIS. THIS REVIEW IS ORGANIZED IN SECTIONS AS FOLLOWS: I) A BRIEF SYNOPSIS OF THE CURRENT STATE OF KNOWLEDGE REGARDING ESTROGEN-INDUCED CARCINOGENESIS, II) A REVIEW OF EVIDENCE FROM CLINICAL AND ANIMAL-BASED STUDIES THAT SUPPORT A ROLE FOR GPER IN CANCER PROGRESSION, AND III) A MECHANISTIC FRAMEWORK DESCRIBING HOW GPER-MEDIATED ESTROGEN ACTION MAY INFLUENCE THE TUMOR AND ITS MICROENVIRONMENT. 2018 2 6272 36 THE ORIGIN AND PATHOGENESIS OF ENDOMETRIOSIS. RECENT MOLECULAR GENETIC FINDINGS ON ENDOMETRIOSIS AND NORMAL ENDOMETRIUM SUGGEST A MODIFIED MODEL IN WHICH CIRCULATING EPITHELIAL PROGENITOR OR STEM CELLS INTENDED TO REGENERATE UTERINE ENDOMETRIUM AFTER MENSTRUATION MAY BECOME OVERREACTIVE AND TRAPPED OUTSIDE THE UTERUS. THESE TRAPPED EPITHELIUM-COMMITTED PROGENITOR CELLS FORM NASCENT GLANDS THROUGH CLONAL EXPANSION AND RECRUIT POLYCLONAL STROMAL CELLS, LEADING TO THE ESTABLISHMENT OF DEEP INFILTRATING ENDOMETRIOSIS. ONCE FORMED, THE ECTOPIC TISSUE BECOMES SUBJECT TO IMMUNE SURVEILLANCE, RESULTING IN CHRONIC INFLAMMATION. THE INFLAMMATORY RESPONSE ORCHESTRATED BY NUCLEAR FACTOR-KAPPAB SIGNALING IS EXACERBATED BY ABERRATIONS IN THE ESTROGEN RECEPTOR-BETA AND PROGESTERONE RECEPTOR PATHWAYS, WHICH ARE ALSO AFFECTED BY LOCAL INFLAMMATION, FORMING A DYSREGULATED INFLAMMATION-HORMONAL LOOP. GLANDULAR EPITHELIUM WITHIN ENDOMETRIOTIC TISSUE HARBORS CANCER-ASSOCIATED MUTATIONS THAT ARE FREQUENTLY DETECTED IN ENDOMETRIOSIS-RELATED OVARIAN CANCERS. IN THIS REVIEW, WE SUMMARIZE RECENT ADVANCES THAT HAVE ILLUMINATED THE ORIGIN AND PATHOGENESIS OF ENDOMETRIOSIS AND HAVE PROVIDED NEW AVENUES FOR RESEARCH THAT PROMISE TO IMPROVE THE EARLY DIAGNOSIS AND MANAGEMENT OF ENDOMETRIOSIS. 2020 3 4310 35 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 4 3820 24 INTRODUCTION TO PRECLINICAL EVIDENCE FROM ANIMAL MODELS OF ENDOMETRIOSIS. ENDOMETRIOSIS, THE PRESENCE AND GROWTH OF UTERINE ENDOMETRIAL GLANDULAR EPITHELIAL AND STROMA CELLS OUTSIDE THE UTERINE CAVITY, CAUSES PAIN AND INFERTILITY IN WOMEN AND GIRLS OF REPRODUCTIVE AGE. AS RANDOMIZED, DOUBLE-BLINDED, CONTROLLED STUDIES OF ENDOMETRIOSIS IN WOMEN ARE IMPRACTICAL AND AT TIMES ETHICALLY PROHIBITIVE, ANIMAL MODELS FOR ENDOMETRIOSIS AROSE AS AN IMPORTANT ADJUNCT TO GAIN MECHANISTIC INSIGHTS INTO THE ETIOLOGY AND PATHOPHYSIOLOGICAL MECHANISMS OF THIS PERPLEXING DISORDER. A MORE THOROUGH UNDERSTANDING OF ENDOMETRIOSIS IN WOMEN MAY HELP DEVELOP NOVEL NONINVASIVE DIAGNOSTICS, CLASSIFICATION SYSTEMS, THERAPEUTIC REGIMES, AND EVEN PREVENTATIVE METHODS FOR THE MANAGEMENT OF ENDOMETRIOSIS. THIS CHAPTER IS INTENDED TO INTRODUCE A BRIEF HISTORICAL BACKGROUND, BIOLOGICAL AND EPIDEMIOLOGICAL ASPECTS, THE MAJOR SYMPTOMS, THE EFFECTS OF ENDOCRINE-DISRUPTING CHEMICALS, AND AN EXAMPLE OF AN EPIGENETIC FACTOR OF ENDOMETRIOSIS IN WOMEN. 2020 5 1891 42 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 6 5241 33 PROGESTERONE RESISTANCE IN ENDOMETRIOSIS: CURRENT EVIDENCE AND PUTATIVE MECHANISMS. ENDOMETRIOSIS IS AN ESTROGEN-DEPENDENT DISEASE CHARACTERIZED BY THE GROWTH OF ENDOMETRIAL-LIKE TISSUE OUTSIDE THE UTERUS. PROGESTINS ARE CURRENTLY THE MOST COMMONLY USED TREATMENT FOR ENDOMETRIOSIS BECAUSE OF THEIR EXCELLENT THERAPEUTIC EFFECTS AND LIMITED SIDE EFFECTS. HOWEVER, PROGESTINS HAVE BEEN UNSUCCESSFUL IN SOME SYMPTOMATIC PATIENTS. THE INABILITY OF THE ENDOMETRIUM TO RESPOND PROPERLY TO PROGESTERONE IS KNOWN AS PROGESTERONE RESISTANCE. AN INCREASING BODY OF EVIDENCE SUGGESTS THE LOSS OF PROGESTERONE SIGNALING AND THE EXISTENCE OF PROGESTERONE RESISTANCE IN ENDOMETRIOSIS. THE MECHANISMS OF PROGESTERONE RESISTANCE HAVE RECEIVED CONSIDERABLE SCHOLARLY ATTENTION IN RECENT YEARS. ABNORMAL PGR SIGNALING, CHRONIC INFLAMMATION, ABERRANT GENE EXPRESSION, EPIGENETIC ALTERATIONS, AND ENVIRONMENTAL TOXINS ARE CONSIDERED POTENTIAL MOLECULAR CAUSES OF PROGESTERONE RESISTANCE IN ENDOMETRIOSIS. THE GENERAL OBJECTIVE OF THIS REVIEW WAS TO SUMMARIZE THE EVIDENCE AND MECHANISMS OF PROGESTERONE RESISTANCE. A DEEPER UNDERSTANDING OF HOW THESE MECHANISMS CONTRIBUTE TO PROGESTERONE RESISTANCE MAY HELP DEVELOP A NOVEL THERAPEUTIC REGIMEN FOR WOMEN WITH ENDOMETRIOSIS BY REVERSING PROGESTERONE RESISTANCE. 2023 7 236 27 ADENOMYOSIS: MECHANISMS AND PATHOGENESIS. ADENOMYOSIS IS A COMMON DISORDER OF THE UTERUS, AND IS ASSOCIATED WITH AN ENLARGED UTERUS, HEAVY MENSTRUAL BLEEDING (HMB), PELVIC PAIN, AND INFERTILITY. IT IS CHARACTERIZED BY ENDOMETRIAL EPITHELIAL CELLS AND STROMAL FIBROBLASTS ABNORMALLY FOUND IN THE MYOMETRIUM WHERE THEY ELICIT HYPERPLASIA AND HYPERTROPHY OF SURROUNDING SMOOTH MUSCLE CELLS. WHILE BOTH THE MECHANISTIC PROCESSES AND THE PATHOGENESIS OF ADENOMYOSIS ARE UNCERTAIN, SEVERAL THEORIES HAVE BEEN PUT FORWARD ADDRESSING HOW THIS DISEASE DEVELOPS. THESE INCLUDE INTRINSIC OR INDUCED (1) MICROTRAUMA OF THE ENDOMETRIAL-MYOMETRIAL INTERFACE; (2) ENHANCED INVASION OF ENDOMETRIUM INTO MYOMETRIUM; (3) METAPLASIA OF STEM CELLS IN MYOMETRIUM; (4) INFILTRATION OF ENDOMETRIAL CELLS IN RETROGRADE MENSTRUAL EFFLUENT INTO THE UTERINE WALL FROM THE SEROSAL SIDE; (5) INDUCTION OF ADENOMYOTIC LESIONS BY ABERRANT LOCAL STEROID AND PITUITARY HORMONES; AND (6) ABNORMAL UTERINE DEVELOPMENT IN RESPONSE TO GENETIC AND EPIGENETIC MODIFICATIONS. DYSMENORRHEA, HMB, AND INFERTILITY ARE LIKELY RESULTS OF INFLAMMATION, NEUROGENESIS, ANGIOGENESIS, AND CONTRACTILE ABNORMALITIES IN THE ENDOMETRIAL AND MYOMETRIAL COMPONENTS. ELUCIDATING MECHANISMS UNDERLYING THE PATHOGENESIS OF ADENOMYOSIS RAISE POSSIBILITIES TO DEVELOP TARGETED THERAPIES TO AMELIORATE SYMPTOMS BEYOND THE CURRENT AGENTS THAT ARE LARGELY INEFFECTIVE. HEREIN, WE ADDRESS THESE POSSIBLE ETIOLOGIES AND DATA THAT SUPPORT UNDERLYING MECHANISMS. 2020 8 5242 31 PROGESTERONE RESISTANCE IN ENDOMETRIOSIS: ORIGINS, CONSEQUENCES AND INTERVENTIONS. ENDOMETRIOSIS IS A COMMON CAUSE OF PELVIC PAIN AND AFFECTS UP TO 10% OF WOMEN OF REPRODUCTIVE AGE. ABERRANT PROGESTERONE SIGNALING IN THE ENDOMETRIUM PLAYS A SIGNIFICANT ROLE IN IMPAIRED DECIDUALIZATION AND ESTABLISHMENT OF ECTOPIC ENDOMETRIAL IMPLANTS. EUTOPIC ENDOMETRIAL CELLS FROM WOMEN WITH ENDOMETRIOSIS FAIL TO DOWNREGULATE GENES NEEDED FOR DECIDUALIZATION, SUCH AS THOSE INVOLVED IN CELL CYCLE REGULATION, LEADING TO UNBRIDLED PROLIFERATION. SEVERAL CAUSES OF PROGESTERONE RESISTANCE IN THE ENDOMETRIUM HAVE BEEN POSTULATED, INCLUDING CONGENITAL "PRECONDITIONING", WHEREBY THE IN UTERO ENVIRONMENT RENDERS INFANTS SUSCEPTIBLE TO NEONATAL UTERINE BLEEDING AND ENDOMETRIOSIS. PROGESTERONE ACTION IS CRUCIAL TO DECREASING INFLAMMATION IN THE ENDOMETRIUM, AND DEVIANT PROGESTERONE SIGNALING RESULTS IN A PROINFLAMMATORY PHENOTYPE. CONVERSELY, CHRONIC INFLAMMATION CAN INDUCE A PROGESTERONE-RESISTANT STATE. REPETITIVE RETROGRADE ENDOMETRIAL SHEDDING BEGETS CHRONIC PERITONEAL INFLAMMATION, WHICH FURTHER EXACERBATES PROGESTERONE RESISTANCE. GENETIC CAUSES OF PROGESTERONE RESISTANCE INCLUDE PROGESTERONE RECEPTOR GENE POLYMORPHISMS, ALTERED MICRORNA EXPRESSION, AND EPIGENETIC MODIFICATIONS TO PROGESTERONE RECEPTORS AND THEIR TARGETS. ENVIRONMENTAL TOXINS SUCH AS DIOXIN PLAY A POSSIBLE ROLE IN THE GENESIS OF ENDOMETRIOSIS BY PERMITTING AN INFLAMMATORY MILIEU. A CONSEQUENCE OF IMPAIRED PROGESTERONE ACTION IS THAT HORMONAL THERAPY IS RENDERED INEFFECTIVE FOR A SUBSET OF WOMEN WITH ENDOMETRIOSIS. SYNTHETIC PROGESTINS, SUCH AS DIENOGEST, MAY OVERCOME THIS PHENOMENON BY INCREASING PROGESTERONE RECEPTOR EXPRESSION AND DECREASING PROINFLAMMATORY CYTOKINES. OTHER MODALITIES INCLUDE HIGH DOSE DEPOT FORMULATIONS OF PROGESTINS, MEDICATED INTRAUTERINE DEVICES AND THE LIKELY ADVENT OF ORAL GNRH ANTAGONISTS. UNEARTHING ROOT CAUSES OF PROGESTERONE INACTION IN ENDOMETRIOSIS WILL AID IN THE DEVELOPMENT OF NOVEL THERAPEUTICS GEARED TOWARD PREVENTION AND TREATMENT. 2017 9 327 38 ALLERGIC INFLAMMATORY MEMORY IN HUMAN RESPIRATORY EPITHELIAL PROGENITOR CELLS. BARRIER TISSUE DYSFUNCTION IS A FUNDAMENTAL FEATURE OF CHRONIC HUMAN INFLAMMATORY DISEASES(1). SPECIALIZED SUBSETS OF EPITHELIAL CELLS-INCLUDING SECRETORY AND CILIATED CELLS-DIFFERENTIATE FROM BASAL STEM CELLS TO COLLECTIVELY PROTECT THE UPPER AIRWAY(2-4). ALLERGIC INFLAMMATION CAN DEVELOP FROM PERSISTENT ACTIVATION(5) OF TYPE 2 IMMUNITY(6) IN THE UPPER AIRWAY, RESULTING IN CHRONIC RHINOSINUSITIS, WHICH RANGES IN SEVERITY FROM RHINITIS TO SEVERE NASAL POLYPS(7). BASAL CELL HYPERPLASIA IS A HALLMARK OF SEVERE DISEASE(7-9), BUT IT IS NOT KNOWN HOW THESE PROGENITOR CELLS(2,10,11) CONTRIBUTE TO CLINICAL PRESENTATION AND BARRIER TISSUE DYSFUNCTION IN HUMANS. HERE WE PROFILE PRIMARY HUMAN SURGICAL CHRONIC RHINOSINUSITIS SAMPLES (18,036 CELLS, N = 12) THAT SPAN THE DISEASE SPECTRUM USING SEQ-WELL FOR MASSIVELY PARALLEL SINGLE-CELL RNA SEQUENCING(12), REPORT TRANSCRIPTOMES FOR HUMAN RESPIRATORY EPITHELIAL, IMMUNE AND STROMAL CELL TYPES AND SUBSETS FROM A TYPE 2 INFLAMMATORY DISEASE, AND MAP KEY MEDIATORS. BY COMPARISON WITH NASAL SCRAPINGS (18,704 CELLS, N = 9), WE DEFINE SIGNATURES OF CORE, HEALTHY, INFLAMED AND POLYP SECRETORY CELLS. WE REVEAL MARKED DIFFERENCES BETWEEN THE EPITHELIAL COMPARTMENTS OF THE NON-POLYP AND POLYP CELLULAR ECOSYSTEMS, IDENTIFYING AND VALIDATING A GLOBAL REDUCTION IN CELLULAR DIVERSITY OF POLYPS CHARACTERIZED BY BASAL CELL HYPERPLASIA, CONCOMITANT DECREASES IN GLANDULAR CELLS, AND PHENOTYPIC SHIFTS IN SECRETORY CELL ANTIMICROBIAL EXPRESSION. WE DETECT AN ABERRANT BASAL PROGENITOR DIFFERENTIATION TRAJECTORY IN POLYPS, AND PROPOSE CELL-INTRINSIC(13), EPIGENETIC(14,15) AND EXTRINSIC FACTORS(11,16,17) THAT LOCK POLYP BASAL CELLS INTO THIS UNCOMMITTED STATE. FINALLY, WE FUNCTIONALLY DEMONSTRATE THAT EX VIVO CULTURED BASAL CELLS RETAIN INTRINSIC MEMORY OF IL-4/IL-13 EXPOSURE, AND TEST THE POTENTIAL FOR CLINICAL BLOCKADE OF THE IL-4 RECEPTOR ALPHA-SUBUNIT TO MODIFY BASAL AND SECRETORY CELL STATES IN VIVO. OVERALL, WE FIND THAT REDUCED EPITHELIAL DIVERSITY STEMMING FROM FUNCTIONAL SHIFTS IN BASAL CELLS IS A KEY CHARACTERISTIC OF TYPE 2 IMMUNE-MEDIATED BARRIER TISSUE DYSFUNCTION. OUR RESULTS DEMONSTRATE THAT EPITHELIAL STEM CELLS MAY CONTRIBUTE TO THE PERSISTENCE OF HUMAN DISEASE BY SERVING AS REPOSITORIES FOR ALLERGIC MEMORIES. 2018 10 2669 38 ESTROGEN- AND PROGESTERONE (P4)-MEDIATED EPIGENETIC MODIFICATIONS OF ENDOMETRIAL STROMAL CELLS (ENSCS) AND/OR MESENCHYMAL STEM/STROMAL CELLS (MSCS) IN THE ETIOPATHOGENESIS OF ENDOMETRIOSIS. ENDOMETRIOSIS IS A COMMON CHRONIC INFLAMMATORY CONDITION IN WHICH ENDOMETRIAL TISSUE APPEARS OUTSIDE THE UTERINE CAVITY. BECAUSE ECTOPIC ENDOMETRIOSIS CELLS EXPRESS BOTH ESTROGEN AND PROGESTERONE (P4) RECEPTORS, THEY GROW AND UNDERGO CYCLIC PROLIFERATION AND BREAKDOWN SIMILAR TO THE ENDOMETRIUM. THIS DEBILITATING GYNECOLOGICAL DISEASE AFFECTS UP TO 15% OF REPRODUCTIVE AGED WOMEN. DESPITE MANY YEARS OF RESEARCH, THE ETIOPATHOGENESIS OF ENDOMETRIAL LESIONS REMAINS UNCLEAR. RETROGRADE TRANSPORT OF THE VIABLE MENSTRUAL ENDOMETRIAL CELLS WITH RETAINED ABILITY FOR ATTACHMENT WITHIN THE PELVIC CAVITY, PROLIFERATION, DIFFERENTIATION AND SUBSEQUENT INVASION INTO THE SURROUNDING TISSUE CONSTITUTES THE RATIONALE FOR WIDELY ACCEPTED IMPLANTATION THEORY. ACCORDINGLY, THE MOST ABUNDANT CELLS IN THE ENDOMETRIUM ARE ENDOMETRIAL STROMAL CELLS (ENSCS). THESE CELLS CONSTITUTE A PARTICULAR POPULATION WITH CLONOGENIC ACTIVITY THAT RESEMBLES PROPERTIES OF MESENCHYMAL STEM/STROMAL CELLS (MSCS). THUS, A SIGNIFICANT ROLE OF STEM CELL-BASED DYSFUNCTION IN FORMATION OF THE INITIAL ENDOMETRIAL LESIONS IS SUSPECTED. THERE IS INCREASING EVIDENCE THAT THE ROLE OF EPIGENETIC MECHANISMS AND PROCESSES IN ENDOMETRIOSIS HAVE BEEN UNDERESTIMATED. THE IMPORTANCE OF EXCESS ESTROGEN EXPOSURE AND P4 RESISTANCE IN EPIGENETIC HOMEOSTASIS FAILURE IN THE ENDOMETRIAL/ENDOMETRIOTIC TISSUE ARE CRUCIAL. EPIGENETIC ALTERATIONS REGARDING TRANSCRIPTION FACTORS OF ESTROGEN AND P4 SIGNALING PATHWAYS IN MSCS ARE ROBUST IN ENDOMETRIOTIC TISSUE. THUS, PERSPECTIVES FOR THE FUTURE MAY INCLUDE MSCS AND ENSCS AS THE TARGETS OF EPIGENETIC THERAPIES IN THE PREVENTION AND TREATMENT OF ENDOMETRIOSIS. HERE, WE REVIEWED THE CURRENT KNOWN CHANGES IN THE EPIGENETIC BACKGROUND OF ENSCS AND MSCS DUE TO ESTROGEN/P4 IMBALANCES IN THE CONTEXT OF ETIOPATHOGENESIS OF ENDOMETRIOSIS. GRAPHICAL ABSTRACT. 2021 11 898 36 CHRONIC EXPOSURE OF MICE TO BISPHENOL-A ALTERS UTERINE FIBROBLAST GROWTH FACTOR SIGNALING AND LEADS TO ABERRANT EPITHELIAL PROLIFERATION. UTERINE EPITHELIAL PROLIFERATION IS REGULATED IN A PARACRINE MANNER BY A COMPLEX INTERPLAY BETWEEN ESTROGEN (E) AND PROGESTERONE (P) SIGNALING, IN WHICH E STIMULATES PROLIFERATION AND P INHIBITS IT. PERTURBATION OF STEROID HORMONE SIGNALING WITHIN THE UTERINE MILIEU COULD CONTRIBUTE TO THE DEVELOPMENT OF ENDOMETRIAL HYPERPLASIA AND CANCER. IT IS WELL ESTABLISHED THAT BISPHENOL-A (BPA) IS AN ENDOCRINE-DISRUPTING CHEMICAL WITH WEAK ESTROGENIC EFFECTS, ALTHOUGH LITTLE IS KNOWN ABOUT HOW IT AFFECTS STEROID HORMONE SIGNALING IN THE ADULT UTERUS. BECAUSE BPA ACTS AS A WEAK E, WE HYPOTHESIZED THAT CHRONIC EXPOSURE TO BPA WOULD CREATE AN IMBALANCE BETWEEN E AND P SIGNALING AND CAUSE CHANGES IN THE UTERUS, SUCH AS ABERRANT EPITHELIAL PROLIFERATION. INDEED, EXPOSURE TO AN ENVIRONMENTALLY RELEVANT DOSE OF BPA HAD A UTEROTROPHIC AFFECT. BPA-TREATED MICE SHOWED INCREASED PROLIFERATION, NOTABLY IN THE GLANDULAR EPITHELIUM, WHICH ARE SITES OF ORIGIN FOR ENDOMETRIAL HYPERPLASIA AND CANCER. INCREASED PROLIFERATION APPEARED TO BE MEDIATED THROUGH A SIMILAR MECHANISM AS E-INDUCED PROLIFERATION, VIA ACTIVATION OF THE FIBROBLAST GROWTH FACTOR RECEPTOR PATHWAY AND PHOSPHORYLATION OF THE ERK1/2 MITOGEN-ACTIVATED PROTEIN KINASES IN THE EPITHELIUM. INTERESTINGLY, BPA REDUCED EXPRESSION OF HEART AND NEURAL CREST DERIVATIVES EXPRESSED 2 (HAND2), A KNOWN MEDIATOR OF THE ANTIPROLIFERATIVE EFFECTS OF P. BPA ALSO INCREASED METHYLATION OF A CPG ISLAND IN THE HAND2 GENE PROMOTER, SUGGESTING THAT BPA MAY PROMOTE EPITHELIAL PROLIFERATION THROUGH EPIGENETIC SILENCING OF ANTIPROLIFERATIVE FACTORS LIKE HAND2. COLLECTIVELY, THESE FINDINGS ESTABLISH THAT CHRONIC EXPOSURE TO BPA IMPAIRS STEROID HORMONE SIGNALING IN THE MOUSE UTERUS, AND MAY CONTRIBUTE TO THE PATHOGENESIS OF UTERINE HYPERPLASIA AND CANCER. 2019 12 1889 29 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 13 1114 30 COMMONALITIES AND DISPARITIES BETWEEN ENDOMETRIOSIS AND CHRONIC ENDOMETRITIS: THERAPEUTIC POTENTIAL OF NOVEL ANTIBIOTIC TREATMENT STRATEGY AGAINST ECTOPIC ENDOMETRIUM. CHRONIC ENDOMETRITIS (CE) IS A LOCAL MUCOSAL INFLAMMATORY DISORDER OF THE UTERINE LINING, WHICH IS HISTOPATHOLOGICALLY RECOGNIZED AS THE UNUSUAL INFILTRATION OF CD138(+) PLASMACYTES INTO THE ENDOMETRIAL STROMAL COMPARTMENT. ACCUMULATING BODY OF RESEARCH DOCUMENTED THAT CE IS ASSOCIATED WITH FEMALE INFERTILITY AND SEVERAL OBSTETRIC/NEONATAL COMPLICATIONS. THE MAJOR CAUSE OF CE IS THOUGHT TO BE INTRAUTERINE INFECTION REPRESENTED BY COMMON BACTERIA (ESCHERICHIA COLI, ENTEROCOCCUS FAECALIS, STREPTOCOCCUS, AND STAPHYLOCOCCUS), MYCOPLASMA/UREAPLASMA, AND MYCOBACTERIUM. ADDITIONALLY, LOCAL DYSBIOSIS IN THE FEMALE REPRODUCTIVE TRACT MAY BE INVOLVED IN THE ONSET AND DEVELOPMENT OF CE. ANTIBIOTIC TREATMENTS AGAINST THESE MICROORGANISMS ARE EFFECTIVE IN THE ELIMINATION OF ENDOMETRIAL STROMAL PLASMACYTES IN THE AFFECTED PATIENTS. MEANWHILE, ENDOMETRIOSIS IS A COMMON FEMALE REPRODUCTIVE TRACT DISEASE CHARACTERIZED BY ENDOMETRIOTIC TISSUES (ECTOPIC ENDOMETRIUM) GROWING OUTSIDE THE UTERUS AND POTENTIALLY CAUSES CHRONIC PELVIC SYMPTOMS (DYSMENORRHEA, DYSPAREUNIA, DYSCHEZIA, AND DYSURIA), INFERTILITY, AND OVARIAN CANCERS. ENDOMETRIOSIS INVOLVES ENDOCRINOLOGICAL, GENETIC, AND EPIGENETIC FACTORS IN ITS ETIOLOGY AND PATHOGENESIS. RECENT STUDIES FOCUS ON IMMUNOLOGICAL, INFLAMMATORY, AND INFECTIOUS ASPECTS OF ENDOMETRIOSIS AND DEMONSTRATE SEVERAL COMMON CHARACTERISTICS BETWEEN ENDOMETRIOSIS AND CE. THIS REVIEW AIMED TO BETTER UNDERSTAND THE IMMUNOLOGICAL AND MICROBIAL BACKGROUNDS UNDERLYING ENDOMETRIOSIS AND CE AND LOOK INTO THE THERAPEUTIC POTENTIAL OF THE NOVEL ANTIBIOTIC TREATMENT STRATEGY AGAINST ENDOMETRIOSIS IN LIGHT OF ENDOMETRIAL INFECTIOUS DISEASE. 2023 14 2602 33 EPIGENETICS, ENDOMETRIOSIS AND SEX STEROID RECEPTORS: AN UPDATE ON THE EPIGENETIC REGULATORY MECHANISMS OF ESTROGEN AND PROGESTERONE RECEPTORS IN PATIENTS WITH ENDOMETRIOSIS. ENDOMETRIOSIS IS A BENIGN GYNECOLOGICAL DISEASE AFFECTING APPROXIMATELY 10% OF REPRODUCTIVE-AGED WOMEN AND IS DEFINED AS THE PRESENCE OF ENDOMETRIAL GLANDS AND STROMA OUTSIDE THE UTERINE CAVITY. ENDOMETRIOSIS CAN CAUSE A VARIETY OF HEALTH PROBLEMS, FROM PELVIC DISCOMFORT TO CATAMENIAL PNEUMOTHORAX, BUT IT'S MAINLY LINKED WITH SEVERE AND CHRONIC PELVIC PAIN, DYSMENORRHEA, AND DEEP DYSPAREUNIA, AS WELL AS REPRODUCTIVE ISSUES. THE PATHOGENESIS OF ENDOMETRIOSIS INVOLVES AN ENDOCRINE DYSFUNCTION, WITH ESTROGEN DEPENDENCY AND PROGESTERONE RESISTANCE, AND INFLAMMATORY MECHANISM ACTIVATION, TOGETHER WITH IMPAIRED CELL PROLIFERATION AND NEUROANGIOGENESIS. THE PRESENT CHAPTER AIMS TO DISCUSS THE MAIN EPIGENETIC MECHANISMS RELATED TO ESTROGEN RECEPTORS (ERS) AND PROGESTERONE RECEPTORS (PRS) IN PATIENTS WITH ENDOMETRIOSIS. THERE ARE NUMEROUS EPIGENETIC MECHANISMS PARTICIPATING IN ENDOMETRIOSIS, REGULATING THE EXPRESSION OF THE GENES ENCODING THESE RECEPTORS BOTH INDIRECTLY, THROUGH THE REGULATION OF TRANSCRIPTION FACTORS, AND DIRECTLY, THROUGH DNA METHYLATION, HISTONE MODIFICATIONS, MICRO RNAS AND LONG NONCODING RNAS. THIS REPRESENTS AN OPEN FIELD OF INVESTIGATION, WHICH MAY LEAD TO IMPORTANT CLINICAL IMPLICATIONS SUCH AS THE DEVELOPMENT OF EPIGENETIC DRUGS FOR THE TREATMENT OF ENDOMETRIOSIS AND THE IDENTIFICATION OF SPECIFIC AND EARLY BIOMARKERS FOR THE DISEASE. 2023 15 4956 24 PATHOGENESIS OF ENDOMETRIOSIS: FOCUS ON ADENOGENESIS-RELATED FACTORS. ENDOMETRIOSIS CAN BE DEFINED AS THE PRESENCE OF THE ENDOMETRIUM OUTSIDE THE UTERINE CAVITY. IT AFFECTS APPROXIMATELY 10% OF WOMEN OF REPRODUCTIVE AGE AND CAUSES INFERTILITY, CHRONIC PAIN, AND DETERIORATION OF THE QUALITY OF LIFE. SINCE THE IDENTIFICATION OF THE DISEASE, VARIOUS PATHOGENETIC MECHANISMS HAVE BEEN PROPOSED, SUCH AS RETROGRADE MENSTRUATION, COELOMIC METAPLASIA, HORMONAL IMBALANCE, STEM CELL INVOLVEMENT, AND ALTERATIONS IN EPIGENETIC REGULATION. HOWEVER, THE UNDERLYING PATHOGENESIS OF ENDOMETRIOSIS REMAINS INADEQUATELY UNDERSTOOD. ELUCIDATION OF THE PRECISE MECHANISM OF THE DEVELOPMENT AND PROGRESSION OF ENDOMETRIOSIS IS CRUCIAL FOR EFFECTIVE TREATMENT. THIS REVIEW PRESENTS THE MAJOR PATHOGENETIC THEORIES OF ENDOMETRIOSIS BASED ON CURRENT RESEARCH STUDIES WITH A MAJOR FOCUS ON THE POTENTIAL ROLE OF UTERINE FACTORS. 2023 16 4129 30 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 17 2575 30 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 18 6237 26 THE MAIN THEORIES ON THE PATHOGENESIS OF ENDOMETRIOSIS. ENDOMETRIOSIS IS A COMPLEX DISEASE, WHICH IS DEFINED BY ABNORMAL GROWTH OF ENDOMETRIAL TISSUE OUTSIDE THE UTERUS. IT AFFECTS ABOUT 10% OF WOMEN OF REPRODUCTIVE AGE ALL OVER THE WORLD. ENDOMETRIOSIS CAUSES SYMPTOMS THAT NOTABLY WORSEN PATIENT'S WELL-BEING-SUCH AS SEVERE PELVIC PAIN, DYSFUNCTION OF THE ORGANS OF PELVIC CAVITY, INFERTILITY AND SECONDARY MENTAL ISSUES. THE DIAGNOSIS OF ENDOMETRIOSIS IS QUITE OFTEN DELAYED BECAUSE OF NONSPECIFIC MANIFESTATIONS. SINCE THE DISEASE WAS DEFINED, SEVERAL DIFFERENT PATHOGENETIC PATHWAYS HAVE BEEN CONSIDERED, INCLUDING RETROGRADE MENSTRUATION, BENIGN METASTASIS, IMMUNE DYSREGULATION, COELOMIC METAPLASIA, HORMONAL DISBALANCE, INVOLVEMENT OF STEM CELLS AND ALTERATIONS IN EPIGENETIC REGULATION, BUT THE TRUE PATHOGENESIS OF ENDOMETRIOSIS REMAINS POORLY UNDERSTOOD. THE KNOWLEDGE OF THE EXACT MECHANISM OF THE ORIGIN AND PROGRESSION OF THIS DISEASE IS SIGNIFICANT FOR THE APPROPRIATE TREATMENT. THEREFORE, THIS REVIEW REPORTS THE MAIN PATHOGENETIC THEORIES OF ENDOMETRIOSIS BASED ON CURRENT STUDIES. 2023 19 2852 33 FROM GASTRIC INFLAMMATION TO GASTRIC CANCER. THE MAJORITY OF GASTRIC ADENOCARCINOMAS ARE RELATED TO CHRONIC INFLAMMATION INDUCED BY HELICOBACTER PYLORI INFECTION. FOR INTESTINAL-TYPE GASTRIC CANCER, A MULTISTEP PROCESS OF MUCOSAL ALTERATIONS LEADING FROM GASTRITIS VIA GLANDULAR ATROPHY, INTESTINAL METAPLASIA AND DYSPLASIA TO INVASIVE CARCINOMA IS WELL RECOGNIZED. ONGOING CLINICAL STUDIES FOCUS ON A 'POINT OF NO RETURN'. IT IS DEFINED AS A SITUATION WHEN CERTAIN ALTERATIONS ARE NO LONGER REVERSIBLE BY H. PYLORI ERADICATION AND PROGRESSION TO GASTRIC CANCER MAY CONTINUE. H. PYLORI AFFECTS THE MUCOSAL AS WELL AS THE SYSTEMIC IMMUNE RESPONSE BY SECRETION OF CYTOKINES AND THE RECRUITMENT OF DISTINCT INFLAMMATORY CELLS. THE IMMUNE RESPONSE IS CHARACTERIZED BY A BALANCE BETWEEN A TH1-DOMINATED RESPONSE AND THE RECRUITMENT OF ANTIGEN-SPECIFIC REGULATORY T CELLS THAT ALLOW THE BACTERIA TO PERSIST IN HUMAN GASTRIC MUCOSA. BESIDES IMMUNE-MEDIATED EFFECTS, H. PYLORI INDUCES CELLULAR ALTERATIONS AS WELL AS GENETIC ALTERATIONS IN GENES THAT ARE ESSENTIAL FOR THE EPIGENETIC INTEGRITY AND MUCOSAL HOMEOSTASIS. THESE GENETIC ALTERATIONS DURING GASTRIC CANCER DEVELOPMENT ARE IN FOCUS OF INTENSIVE RESEARCH AND SHOULD ULTIMATELY ALLOW THE IDENTIFICATION OF RISK FACTORS INVOLVED IN GASTRIC CARCINOGENESIS. THE DETECTION OF INDIVIDUALS AT HIGH RISK FOR GASTRIC CANCER WOULD HELP TO DESIGN APPROPRIATE STRATEGIES FOR PREVENTION AND SURVEILLANCE. 2010 20 2668 34 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