1 4563 134 MYELOID DNA METHYLTRANSFERASE3B DEFICIENCY AGGRAVATES PULMONARY FIBROSIS BY ENHANCING PROFIBROTIC MACROPHAGE ACTIVATION. BACKGROUND: IDIOPATHIC PULMONARY FIBROSIS (IPF) IS A CHRONIC, PROGRESSIVE AND SEVERE DISEASE CHARACTERIZED BY EXCESSIVE MATRIX DEPOSITION IN THE LUNGS. MACROPHAGES PLAY CRUCIAL ROLES IN MAINTAINING LUNG HOMEOSTASIS BUT ARE ALSO CENTRAL IN THE PATHOGENESIS OF LUNG DISEASES LIKE PULMONARY FIBROSIS. ESPECIALLY, MACROPHAGE POLARIZATION/ACTIVATION SEEMS TO PLAY A CRUCIAL ROLE IN PATHOLOGY AND EPIGENETIC REPROGRAMING IS WELL-KNOWN TO REGULATE MACROPHAGE POLARIZATION. DNA METHYLATION ALTERATIONS IN IPF LUNGS HAVE BEEN WELL DOCUMENTED, BUT THE ROLE OF DNA METHYLATION IN SPECIFIC CELL TYPES, ESPECIALLY MACROPHAGES, IS POORLY DEFINED. METHODS: IN ORDER TO DETERMINE THE ROLE OF DNA METHYLATION IN MACROPHAGES DURING PULMONARY FIBROSIS, WE SUBJECTED MACROPHAGE SPECIFIC DNA METHYLTRANSFERASE (DNMT)3B, WHICH MEDIATES THE DE NOVO DNA METHYLATION, DEFICIENT MICE TO THE BLEOMYCIN-INDUCED PULMONARY FIBROSIS MODEL. MACROPHAGE POLARIZATION AND FIBROTIC PARAMETERS WERE EVALUATED AT 21 DAYS AFTER BLEOMYCIN ADMINISTRATION. DNMT3B KNOCKOUT AND WILD TYPE BONE MARROW-DERIVED MACROPHAGES WERE STIMULATED WITH EITHER INTERLEUKIN (IL)4 OR TRANSFORMING GROWTH FACTOR BETA 1 (TGFB1) IN VITRO, AFTER WHICH PROFIBROTIC GENE EXPRESSION AND DNA METHYLATION AT THE ARG1 PROMOTOR WERE DETERMINED. RESULTS: WE SHOW THAT DNMT3B DEFICIENCY PROMOTES ALTERNATIVE MACROPHAGE POLARIZATION INDUCED BY IL4 AND TGFB1 IN VITRO AND ALSO ENHANCES PROFIBROTIC MACROPHAGE POLARIZATION IN THE ALVEOLAR SPACE DURING PULMONARY FIBROSIS IN VIVO. MOREOVER, MYELOID SPECIFIC DELETION OF DNMT3B PROMOTED THE DEVELOPMENT OF EXPERIMENTAL PULMONARY FIBROSIS. CONCLUSIONS: IN SUMMARY, THESE DATA SUGGEST THAT MYELOID DNMT3B REPRESSES FIBROTIC MACROPHAGE POLARIZATION AND PROTECTS AGAINST BLEOMYCIN INDUCED PULMONARY FIBROSIS. 2022 2 172 40 ABSENCE OF HDAC3 BY MATRIX STIFFNESS PROMOTES CHROMATIN REMODELING AND FIBROBLAST ACTIVATION IN IDIOPATHIC PULMONARY FIBROSIS. IDIOPATHIC PULMONARY FIBROSIS (IPF) IS A CHRONIC AND FATAL DISEASE CHARACTERIZED BY PROGRESSIVE AND IRREVERSIBLE LUNG SCARRING ASSOCIATED WITH PERSISTENT ACTIVATION OF FIBROBLASTS. EPIGENETICS COULD INTEGRATE DIVERSE MICROENVIRONMENTAL SIGNALS, SUCH AS STIFFNESS, TO DIRECT PERSISTENT FIBROBLAST ACTIVATION. HISTONE MODIFICATIONS BY DEACETYLASES (HDAC) MAY PLAY AN ESSENTIAL ROLE IN THE GENE EXPRESSION CHANGES INVOLVED IN THE PATHOLOGICAL REMODELING OF THE LUNG. PARTICULARLY, HDAC3 IS CRUCIAL FOR MAINTAINING CHROMATIN AND REGULATING GENE EXPRESSION, BUT LITTLE IS KNOWN ABOUT ITS ROLE IN IPF. IN THE STUDY, CONTROL AND IPF-DERIVED FIBROBLASTS WERE USED TO DETERMINE THE INFLUENCE OF HDAC3 ON CHROMATIN REMODELING AND GENE EXPRESSION ASSOCIATED WITH IPF SIGNATURE. ADDITIONALLY, THE CELLS WERE GROWN ON HYDROGELS TO MIMIC THE STIFFNESS OF A FIBROTIC LUNG. OUR RESULTS SHOWED A DECREASED HDAC3 IN THE NUCLEUS OF IPF FIBROBLASTS, WHICH CORRELATES WITH CHANGES IN NUCLEUS SIZE AND HETEROCHROMATIN LOSS. THE INHIBITION OF HDAC3 WITH A PHARMACOLOGICAL INHIBITOR CAUSES HYPERACETYLATION OF H3K9 AND PROVOKES AN INCREASED EXPRESSION OF COL1A1, ACTA2, AND P21. COMPARABLE RESULTS WERE FOUND IN HYDROGELS, WHERE MATRIX STIFFNESS PROMOTES THE LOSS OF NUCLEAR HDAC3 AND INCREASES THE PROFIBROTIC SIGNATURE. FINALLY, LATRUNCULIN B WAS USED TO CONFIRM THAT CHANGES BY STIFFNESS DEPEND ON THE MECHANOTRANSDUCTION SIGNALS. TOGETHER, THESE RESULTS SUGGEST THAT HDAC3 COULD BE A LINK BETWEEN EPIGENETIC MECHANISMS AND THE FIBROTIC MICROENVIRONMENT. 2023 3 2493 39 EPIGENETICS AND CHROMATIN REMODELING PLAY A ROLE IN LUNG DISEASE. EPIGENETICS IS DEFINED AS HERITABLE CHANGES THAT AFFECT GENE EXPRESSION WITHOUT ALTERING THE DNA SEQUENCE. EPIGENETIC REGULATION OF GENE EXPRESSION IS FACILITATED THROUGH DIFFERENT MECHANISMS SUCH AS DNA METHYLATION, HISTONE MODIFICATIONS AND RNA-ASSOCIATED SILENCING BY SMALL NON-CODING RNAS. ALL THESE MECHANISMS ARE CRUCIAL FOR NORMAL DEVELOPMENT, DIFFERENTIATION AND TISSUE-SPECIFIC GENE EXPRESSION. THESE THREE SYSTEMS INTERACT AND STABILIZE ONE ANOTHER AND CAN INITIATE AND SUSTAIN EPIGENETIC SILENCING, THUS DETERMINING HERITABLE CHANGES IN GENE EXPRESSION. HISTONE ACETYLATION REGULATES DIVERSE CELLULAR FUNCTIONS INCLUDING INFLAMMATORY GENE EXPRESSION, DNA REPAIR AND CELL PROLIFERATION. TRANSCRIPTIONAL COACTIVATORS POSSESS INTRINSIC HISTONE ACETYLTRANSFERASE ACTIVITY AND THIS ACTIVITY DRIVES INFLAMMATORY GENE EXPRESSION. ELEVEN CLASSICAL HISTONE DEACETYLASES (HDACS) ACT TO REGULATE THE EXPRESSION OF DISTINCT SUBSETS OF INFLAMMATORY/IMMUNE GENES. THUS, LOSS OF HDAC ACTIVITY OR THE PRESENCE OF HDAC INHIBITORS CAN FURTHER ENHANCE INFLAMMATORY GENE EXPRESSION BY PRODUCING A GENE-SPECIFIC CHANGE IN HAT ACTIVITY. FOR EXAMPLE, HDAC2 EXPRESSION AND ACTIVITY ARE REDUCED IN LUNG MACROPHAGES, BIOPSY SPECIMENS, AND BLOOD CELLS FROM PATIENTS WITH SEVERE ASTHMA AND SMOKING ASTHMATICS, AS WELL AS IN PATIENTS WITH CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD). THIS MAY ACCOUNT, AT LEAST IN PART, FOR THE ENHANCED INFLAMMATION AND REDUCED STEROID RESPONSIVENESS SEEN IN THESE PATIENTS. OTHER PROTEINS, PARTICULARLY TRANSCRIPTION FACTORS, ARE ALSO ACETYLATED AND ARE TARGETS FOR DEACETYLATION BY HDACS AND SIRTUINS, A RELATED FAMILY OF 7 PREDOMINANTLY PROTEIN DEACETYLASES. THUS THE ACETYLATION/DEACETYLATION STATUS OF NF-KAPPAB AND THE GLUCOCORTICOID RECEPTOR CAN ALSO AFFECT THE OVERALL EXPRESSION PATTERN OF INFLAMMATORY GENES AND REGULATE THE INFLAMMATORY RESPONSE. UNDERSTANDING AND TARGETING SPECIFIC ENZYMES INVOLVED IN THIS PROCESS MIGHT LEAD TO NEW THERAPEUTIC AGENTS, PARTICULARLY IN SITUATIONS IN WHICH CURRENT ANTI-INFLAMMATORY THERAPIES ARE SUBOPTIMAL. 2011 4 2228 31 EPIGENETIC MODIFICATIONS OF HISTONES IN PERIODONTAL DISEASE. PERIODONTITIS IS A CHRONIC INFECTIOUS DISEASE DRIVEN BY DYSBIOSIS, AN IMBALANCE BETWEEN COMMENSAL BACTERIA AND THE HOST ORGANISM. PERIODONTITIS IS A LEADING CAUSE OF TOOTH LOSS IN ADULTS AND OCCURS IN ABOUT 50% OF THE US POPULATION. IN ADDITION TO THE CLINICAL CHALLENGES ASSOCIATED WITH TREATING PERIODONTITIS, THE PROGRESSION AND CHRONIC NATURE OF THIS DISEASE SERIOUSLY AFFECT HUMAN HEALTH. EMERGING EVIDENCE SUGGESTS THAT PERIODONTITIS IS ASSOCIATED WITH MECHANISMS BEYOND BACTERIA-INDUCED PROTEIN AND TISSUE DEGRADATION. HERE, WE HYPOTHESIZE THAT BACTERIA ARE ABLE TO INDUCE EPIGENETIC MODIFICATIONS IN ORAL EPITHELIAL CELLS MEDIATED BY HISTONE MODIFICATIONS. IN THIS STUDY, WE FOUND THAT DYSBIOSIS IN VIVO LED TO EPIGENETIC MODIFICATIONS, INCLUDING ACETYLATION OF HISTONES AND DOWNREGULATION OF DNA METHYLTRANSFERASE 1. IN ADDITION, IN VITRO EXPOSURE OF ORAL EPITHELIAL CELLS TO LIPOPOLYSACCHARIDES RESULTED IN HISTONE MODIFICATIONS, ACTIVATION OF TRANSCRIPTIONAL COACTIVATORS, SUCH AS P300/CBP, AND ACCUMULATION OF NUCLEAR FACTOR-KAPPAB (NF-KAPPAB). GIVEN THAT ORAL EPITHELIAL CELLS ARE THE FIRST LINE OF DEFENSE FOR THE PERIODONTIUM AGAINST BACTERIA, WE ALSO EVALUATED WHETHER ACTIVATION OF PATHOGEN RECOGNITION RECEPTORS INDUCED HISTONE MODIFICATIONS. WE FOUND THAT ACTIVATION OF THE TOLL-LIKE RECEPTORS 1, 2, AND 4 AND THE NUCLEOTIDE-BINDING OLIGOMERIZATION DOMAIN PROTEIN 1 INDUCED HISTONE ACETYLATION IN ORAL EPITHELIAL CELLS. OUR FINDINGS CORROBORATE THE EMERGING CONCEPT THAT EPIGENETIC MODIFICATIONS PLAY A ROLE IN THE DEVELOPMENT OF PERIODONTITIS. 2016 5 3795 32 INTERLEUKIN-6 CONTRIBUTES TO GROWTH IN CHOLANGIOCARCINOMA CELLS BY ABERRANT PROMOTER METHYLATION AND GENE EXPRESSION. THE ASSOCIATION BETWEEN CHRONIC INFLAMMATION AND THE DEVELOPMENT AND PROGRESSION OF MALIGNANCY IS EXEMPLIFIED IN THE BILIARY TRACT WHERE PERSISTENT INFLAMMATION STRONGLY PREDISPOSES TO CHOLANGIOCARCINOMA. THE INFLAMMATORY CYTOKINE INTERLEUKIN-6 (IL-6) ENHANCES TUMOR GROWTH IN CHOLANGIOCARCINOMA BY ALTERED GENE EXPRESSION VIA AUTOCRINE MECHANISMS. IL-6 CAN REGULATE THE ACTIVITY OF DNA METHYLTRANSFERASES, AND MOREOVER, ABERRANT DNA METHYLATION CAN CONTRIBUTE TO CARCINOGENESIS. WE THEREFORE INVESTIGATED THE EFFECT OF CHRONIC EXPOSURE TO IL-6 ON METHYLATION-DEPENDENT GENE EXPRESSION AND TRANSFORMED CELL GROWTH IN HUMAN CHOLANGIOCARCINOMA. THE RELATIONSHIP BETWEEN AUTOCRINE IL-6 PATHWAYS, DNA METHYLATION, AND TRANSFORMED CELL GROWTH WAS ASSESSED USING MALIGNANT CHOLANGIOCYTES STABLY TRANSFECTED TO OVEREXPRESS IL-6. TREATMENT WITH THE DNA METHYLATION INHIBITOR 5-AZA-2'-DEOXYCYTIDINE DECREASED CELL PROLIFERATION, GROWTH IN SOFT AGAR, AND METHYLCYTOSINE CONTENT OF MALIGNANT CHOLANGIOCYTES. HOWEVER, THIS EFFECT WAS NOT OBSERVED IN IL-6-OVEREXPRESSING CELLS. IL-6 OVEREXPRESSION RESULTED IN THE ALTERED EXPRESSION AND PROMOTER METHYLATION OF SEVERAL GENES, INCLUDING THE EPIDERMAL GROWTH FACTOR RECEPTOR (EGFR). EGFR PROMOTER METHYLATION WAS DECREASED AND GENE AND PROTEIN EXPRESSION WAS INCREASED BY IL-6. THUS, EPIGENETIC REGULATION OF GENE EXPRESSION BY IL-6 CAN CONTRIBUTE TO TUMOR PROGRESSION BY ALTERING PROMOTER METHYLATION AND GENE EXPRESSION OF GROWTH-REGULATORY PATHWAYS, SUCH AS THOSE INVOLVING EGFR. MOREOVER, ENHANCED IL-6 EXPRESSION MAY DECREASE THE SENSITIVITY OF TUMOR CELLS TO THERAPEUTIC TREATMENTS USING METHYLATION INHIBITORS. THESE OBSERVATIONS HAVE IMPORTANT IMPLICATIONS FOR CANCER TREATMENT AND PROVIDE A MECHANISM BY WHICH PERSISTENT CYTOKINE STIMULATION CAN PROMOTE TUMOR GROWTH. 2006 6 476 42 ARSENIC INDUCES FIBROGENIC CHANGES IN HUMAN KIDNEY EPITHELIAL CELLS POTENTIALLY THROUGH EPIGENETIC ALTERATIONS IN DNA METHYLATION. ARSENIC CONTAMINATION IS A SIGNIFICANT PUBLIC HEALTH ISSUE, AND KIDNEY IS ONE OF THE TARGET ORGAN FOR ARSENIC-INDUCED ADVERSE EFFECTS. RENAL FIBROSIS IS A WELL-KNOWN PATHOLOGICAL STAGE FREQUENTLY OBSERVED IN PROGRESSIVE CHRONIC KIDNEY DISEASE (CKD). EPIDEMIOLOGICAL STUDIES IMPLICATE ARSENIC EXPOSURE TO CKD, BUT THE ROLE OF ARSENIC IN KIDNEY FIBROSIS AND THE UNDERLYING MECHANISM IS STILL UNCLEAR. IT IS IN THIS CONTEXT THAT THE CURRENT STUDY EVALUATED THE EFFECTS OF LONG-TERM ARSENIC EXPOSURE ON THE CELLULAR RESPONSE IN MORPHOLOGY, AND MARKER GENES EXPRESSION WITH RESPECT TO FIBROSIS USING HUMAN KIDNEY 2 (HK-2) EPITHELIAL CELLS. RESULTS OF THIS STUDY REVEALED THAT IN ADDITION TO INCREASED GROWTH, HK-2 CELLS UNDERWENT PHENOTYPIC, BIOCHEMICAL AND MOLECULAR CHANGES INDICATIVE OF EPITHELIAL-MESENCHYMAL TRANSITION (EMT) IN RESPONSE TO THE EXPOSURE TO ARSENIC. MOST IMPORTANTLY, THE ARSENIC-EXPOSED CELLS ACQUIRED THE PATHOGENIC FEATURES OF FIBROSIS AS SUPPORTED BY INCREASED EXPRESSION OF MARKERS FOR FIBROSIS, SUCH AS COLLAGEN I, FIBRONECTIN, TRANSFORMING GROWTH FACTOR BETA, AND ALPHA-SMOOTH MUSCLE ACTIN. UPREGULATION OF FIBROSIS ASSOCIATED SIGNALING MOLECULES SUCH AS TISSUE INHIBITOR OF METALLOPROTEINASES-3 AND MATRIX METALLOPROTEINASE-2 AS WELL AS ACTIVATION OF AKT WAS ALSO OBSERVED. ADDITIONALLY, THE EXPRESSION OF EPIGENETIC GENES (DNA METHYLTRANSFERASES 3A AND 3B; METHYL-CPG BINDING DOMAIN 4) WAS INCREASED IN ARSENIC-EXPOSED CELLS. TREATMENT WITH DNA METHYLATION INHIBITOR 5-AZA-2'-DC REVERSED THE EMT PROPERTIES AND RESTORED THE LEVEL OF PHOSPHO-AKT. TOGETHER, THESE DATA FOR THE FIRST TIME SUGGEST THAT LONG-TERM EXPOSURE TO ARSENIC CAN INCREASE THE RISK OF KIDNEY FIBROSIS. ADDITIONALLY, OUR DATA SUGGEST THAT THE ARSENIC-INDUCED FIBROTIC CHANGES ARE, AT LEAST IN PART, MEDIATED BY DNA METHYLATION AND THEREFORE POTENTIALLY CAN BE REVERSED BY EPIGENETIC THERAPEUTICS. 2019 7 141 25 ABERRANT DNA METHYLATION OF MTOR PATHWAY GENES PROMOTES INFLAMMATORY ACTIVATION OF IMMUNE CELLS IN DIABETIC KIDNEY DISEASE. DNA METHYLATION HAS BEEN IMPLICATED IN THE PATHOGENESIS OF DIABETIC KIDNEY DISEASE (DKD), BUT THE UNDERLYING MECHANISMS REMAIN UNCLEAR. IN THIS STUDY, WE TESTED THE HYPOTHESIS THAT ABERRANT DNA METHYLATION IN PERIPHERAL IMMUNE CELLS CONTRIBUTES TO DKD PROGRESSION. WE SHOWED THAT LEVELS OF DNA METHYLTRANSFERASE 1 (DNMT1), A KEY ENZYME FOR DNA METHYLATION, WERE INCREASED ALONG WITH INFLAMMATORY ACTIVITY OF PERIPHERAL BLOOD MONONUCLEAR CELLS IN DKD PATIENTS. INHIBITION OF DNMT1 WITH 5-AZA-2'-DEOXYCYTIDINE (5-AZA) MARKEDLY INCREASED THE PROPORTION OF CD4(+)CD25(+) REGULATORY T CELLS IN PERIPHERAL BLOOD MONONUCLEAR CELLS IN CULTURE AND IN DIABETIC ANIMALS. ADOPTIVE TRANSFER OF IMMUNE CELLS FROM 5-AZA-TREATED ANIMALS SHOWED BENEFICIAL EFFECTS ON THE HOST IMMUNE SYSTEM, RESULTING IN A SIGNIFICANT IMPROVEMENT OF DKD. USING GENOME-WIDE DNA METHYLATION ASSAYS, WE IDENTIFIED THE DIFFERENTIALLY METHYLATED CYTOSINES IN THE PROMOTER REGIONS OF MAMMALIAN TARGET OF RAPAMYCIN (MTOR) REGULATORS IN PERIPHERAL BLOOD MONONUCLEAR CELLS OF DIABETIC PATIENTS. FURTHER, MRNA ARRAYS CONFIRMED THE CONSISTENT INDUCTION OF GENES EXPRESSED IN THE MTOR PATHWAY. IMPORTANTLY, DOWN-REGULATION OF DNMT1 EXPRESSION VIA RNA INTERFERENCE RESULTED IN PROMINENT CYTOSINE DEMETHYLATION OF MTOR NEGATIVE REGULATORS AND SUBSEQUENT DECREASE OF MTOR ACTIVITY. LASTLY, MODULATION OF MTOR RESULTED IN CHANGES IN THE EFFECT OF 5-AZA ON DIABETIC IMMUNE CELLS. THUS, UP-REGULATION OF DNMT1 IN DIABETIC IMMUNE CELLS INDUCES ABERRANT CYTOSINE METHYLATION OF THE UPSTREAM REGULATORS OF MTOR, LEADING TO PATHOGENIC ACTIVATION OF THE MTOR PATHWAY AND CONSEQUENT INFLAMMATION IN DIABETIC KIDNEYS. HENCE, THIS STUDY HIGHLIGHTS THERAPEUTIC POTENTIAL OF TARGETING EPIGENETIC EVENTS IN IMMUNE SYSTEM FOR TREATING DKD. 2019 8 2169 35 EPIGENETIC MECHANISMS IN PARENCHYMAL LUNG DISEASES: BYSTANDERS OR THERAPEUTIC TARGETS? EPIGENETIC RESPONSES DUE TO ENVIRONMENTAL CHANGES ALTER CHROMATIN STRUCTURE, WHICH IN TURN MODIFIES THE PHENOTYPE, GENE EXPRESSION PROFILE, AND ACTIVITY OF EACH CELL TYPE THAT HAS A ROLE IN THE PATHOPHYSIOLOGY OF A DISEASE. PULMONARY DISEASES ARE ONE OF THE MAJOR CAUSES OF DEATH IN THE WORLD, INCLUDING LUNG CANCER, IDIOPATHIC PULMONARY FIBROSIS (IPF), CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD), PULMONARY HYPERTENSION (PH), LUNG TUBERCULOSIS, PULMONARY EMBOLISM, AND ASTHMA. SEVERAL LINES OF EVIDENCE INDICATE THAT EPIGENETIC MODIFICATIONS MAY BE ONE OF THE MAIN FACTORS TO EXPLAIN THE INCREASING INCIDENCE AND PREVALENCE OF LUNG DISEASES INCLUDING IPF AND COPD. INTERESTINGLY, ISOLATED FIBROBLASTS AND SMOOTH MUSCLE CELLS FROM PATIENTS WITH PULMONARY DISEASES SUCH AS IPF AND PH THAT WERE CULTURED EX VIVO MAINTAINED THE DISEASE PHENOTYPE. THE CELLS OFTEN SHOW A HYPER-PROLIFERATIVE, APOPTOSIS-RESISTANT PHENOTYPE WITH INCREASED EXPRESSION OF EXTRACELLULAR MATRIX (ECM) AND ACTIVATED FOCAL ADHESIONS SUGGESTING THE PRESENCE OF AN EPIGENETICALLY IMPRINTED PHENOTYPE. MOREOVER, MANY ABNORMALITIES OBSERVED IN MOLECULAR PROCESSES IN IPF PATIENTS ARE SHOWN TO BE EPIGENETICALLY REGULATED, SUCH AS INNATE IMMUNITY, CELLULAR SENESCENCE, AND APOPTOTIC CELL DEATH. DNA METHYLATION, HISTONE MODIFICATION, AND MICRORNA REGULATION CONSTITUTE THE MOST COMMON EPIGENETIC MODIFICATION MECHANISMS. 2022 9 3659 29 INDUCTION OF EPIGENETIC ALTERATIONS BY CHRONIC INFLAMMATION AND ITS SIGNIFICANCE ON CARCINOGENESIS. CHRONIC INFLAMMATION IS DEEPLY INVOLVED IN DEVELOPMENT OF HUMAN CANCERS, SUCH AS GASTRIC AND LIVER CANCERS. INDUCTION OF CELL PROLIFERATION, PRODUCTION OF REACTIVE OXYGEN SPECIES, AND DIRECT STIMULATION OF EPITHELIAL CELLS BY INFLAMMATION-INDUCING FACTORS HAVE BEEN CONSIDERED AS MECHANISMS INVOLVED. INFLAMMATION-RELATED CANCERS ARE KNOWN FOR THEIR MULTIPLE OCCURRENCES, AND ABERRANT DNA METHYLATION IS KNOWN TO BE PRESENT EVEN IN NONCANCEROUS TISSUES. IMPORTANTLY, FOR SOME CANCERS, THE DEGREE OF ACCUMULATION HAS BEEN DEMONSTRATED TO BE CORRELATED WITH RISK OF DEVELOPING CANCERS. THIS INDICATES THAT INFLAMMATION INDUCES ABERRANT EPIGENETIC ALTERATIONS IN A TISSUE EARLY IN THE PROCESS OF CARCINOGENESIS, AND ACCUMULATION OF SUCH ALTERATIONS FORMS "AN EPIGENETIC FIELD FOR CANCERIZATION." THIS ALSO SUGGESTS THAT INHIBITION OF INDUCTION OF EPIGENETIC ALTERATIONS AND REMOVAL OF THE ACCUMULATED ALTERATIONS ARE NOVEL APPROACHES TO CANCER PREVENTION. DISTURBANCES IN CYTOKINE AND CHEMOKINE SIGNALS AND INDUCTION OF CELL PROLIFERATIONS ARE IMPORTANT MECHANISMS OF HOW INFLAMMATION INDUCES ABERRANT DNA METHYLATION. ABERRANT DNA METHYLATION IS INDUCED IN SPECIFIC GENES, AND GENE EXPRESSION LEVELS, THE PRESENCE OF RNA POLYMERASE II (ACTIVE OR STALLED), AND TRIMETHYLATION OF H3K4 ARE INVOLVED IN THE SPECIFICITY. EXPRESSION OF DNA METHYLTRANSFERASES (DNMTS) IS NOT NECESSARILY INDUCED BY INFLAMMATION, AND LOCAL IMBALANCE BETWEEN DNMTS AND FACTORS THAT PROTECT GENES FROM DNA METHYLATION SEEMS TO BE IMPORTANT. 2010 10 4111 30 MECHANISMS CONTRIBUTING TO PERSISTENTLY ACTIVATED CELL PHENOTYPES IN PULMONARY HYPERTENSION. CHRONIC PULMONARY HYPERTENSION (PH) IS CHARACTERIZED BY THE ACCUMULATION OF PERSISTENTLY ACTIVATED CELL TYPES IN THE PULMONARY VESSEL EXHIBITING ABERRANT EXPRESSION OF GENES INVOLVED IN APOPTOSIS RESISTANCE, PROLIFERATION, INFLAMMATION AND EXTRACELLULAR MATRIX (ECM) REMODELLING. CURRENT THERAPIES FOR PH, FOCUSING ON VASODILATATION, DO NOT NORMALIZE THESE ACTIVATED PHENOTYPES. FURTHERMORE, CURRENT APPROACHES TO DEFINE ADDITIONAL THERAPEUTIC TARGETS HAVE FOCUSED ON DETERMINING THE INITIATING SIGNALS AND THEIR DOWNSTREAM EFFECTORS THAT ARE IMPORTANT IN PH ONSET AND DEVELOPMENT. ALTHOUGH THESE APPROACHES HAVE PRODUCED A LARGE NUMBER OF COMPELLING PH TREATMENT TARGETS, MANY PROMISING HUMAN DRUGS HAVE FAILED IN PH CLINICAL TRIALS. HEREIN, WE PROPOSE THAT ONE CONTRIBUTING FACTOR TO THESE FAILURES IS THAT PROCESSES IMPORTANT IN PH DEVELOPMENT MAY NOT BE GOOD TREATMENT TARGETS IN THE ESTABLISHED PHASE OF CHRONIC PH. WE HYPOTHESIZE THAT THIS IS DUE TO ALTERATIONS OF CHROMATIN STRUCTURE IN PH CELLS, RESULTING IN FUNCTIONAL DIFFERENCES BETWEEN THE SAME FACTOR OR PATHWAY IN NORMAL OR EARLY PH CELLS VERSUS CELLS IN CHRONIC PH. WE PROPOSE THAT THE HIGH EXPRESSION OF GENES INVOLVED IN THE PERSISTENTLY ACTIVATED PHENOTYPE OF PH VASCULAR CELLS IS PERPETUATED BY AN OPEN CHROMATIN STRUCTURE AND MULTIPLE TRANSCRIPTION FACTORS (TFS) VIA THE RECRUITMENT OF HIGH LEVELS OF EPIGENETIC REGULATORS INCLUDING THE HISTONE ACETYLASES P300/CBP, HISTONE ACETYLATION READERS INCLUDING BRDS, THE MEDIATOR COMPLEX AND THE POSITIVE TRANSCRIPTION ELONGATION FACTOR (ABSTRACT FIGURE). THUS, DETERMINING HOW GENE EXPRESSION IS CONTROLLED BY EXAMINING CHROMATIN STRUCTURE, TFS AND EPIGENETIC REGULATORS ASSOCIATED WITH ABERRANTLY EXPRESSED GENES IN PULMONARY VASCULAR CELLS IN CHRONIC PH, MAY UNCOVER NEW PH THERAPEUTIC TARGETS. 2019 11 2067 30 EPIGENETIC CONTROL OF MACROPHAGE SHAPE TRANSITION TOWARDS AN ATYPICAL ELONGATED PHENOTYPE BY HISTONE DEACETYLASE ACTIVITY. INFLAMMATORY CHRONIC PATHOLOGIES ARE COMPLEX PROCESSES CHARACTERIZED BY AN IMBALANCE BETWEEN THE RESOLUTION OF THE INFLAMMATORY PHASE AND THE ESTABLISHMENT OF TISSUE REPAIR. THE MAIN PLAYERS IN THESE INFLAMMATORY PATHOLOGIES ARE BONE MARROW DERIVED MONOCYTES (BMDMS). HOWEVER, HOW MONOCYTE DIFFERENTIATION IS MODULATED TO GIVE RISE TO SPECIFIC MACROPHAGE SUBPOPULATIONS (M1 OR M2) THAT MAY EITHER MAINTAIN THE CHRONIC INFLAMMATORY PROCESS OR LEAD TO WOUND HEALING IS STILL UNCLEAR. CONSIDERING THAT INHIBITORS OF HISTONE DEACETYLASE (HDAC) HAVE AN ANTI-INFLAMMATORY ACTIVITY, WE ASKED WHETHER THIS ENZYME WOULD PLAY A ROLE ON MONOCYTE DIFFERENTIATION INTO M1 OR M2 PHENOTYPE AND IN THE CELL SHAPE TRANSITION THAT FOLLOWS. WE THEN INDUCED MURINE BONE MARROW PROGENITORS INTO MONOCYTE/MACROPHAGE DIFFERENTIATION PATHWAY USING MEDIA CONTAINING GM-CSF AND THE HDAC BLOCKER, TRICHOSTATIN A (TSA). WE FOUND THAT THE PHARMACOLOGICAL INHIBITION OF HDAC ACTIVITY LED TO A SHAPE TRANSITION FROM THE TYPICAL MACROPHAGE PANCAKE-LIKE SHAPE INTO AN ELONGATED MORPHOLOGY, WHICH WAS CORRELATED TO A MIXED M1/M2 PROFILE OF CYTOKINE AND CHEMOKINE SECRETION. OUR RESULTS PRESENT, FOR THE FIRST TIME, THAT HDAC ACTIVITY ACTS AS A REGULATOR OF MACROPHAGE DIFFERENTIATION IN THE ABSENCE OF LYMPHOCYTE STIMULI. WE PROPOSE THAT HDAC ACTIVITY DOWN REGULATES MACROPHAGE PLASTICITY FAVORING THE PRO-INFLAMMATORY PHENOTYPE. 2015 12 6431 35 THE USE OF TARGETED NEXT GENERATION SEQUENCING TO EXPLORE CANDIDATE REGULATORS OF TGF-BETA1'S IMPACT ON KIDNEY CELLS. AIMS/HYPOTHESIS: TRANSFORMING GROWTH FACTOR-BETA (TGF-BETA1) PLAYS AN IMPORTANT REGULATORY ROLE IN THE PROGRESSION OF CHRONIC KIDNEY FAILURE. FURTHER, DAMAGE TO KIDNEY GLOMERULAR MESANGIAL CELLS IS CENTRAL TO THE PROGRESSION OF DIABETIC NEPHROPATHY. THE AIM OF THIS STUDY WAS TO EXPLORE THE GENETIC ASSOCIATIONS BETWEEN MRNA, MICRORNA, AND EPIGENETICS IN MESANGIAL CELLS IN RESPONSE TO TGF-BETA1. METHODS: THE REGULATORY EFFECTS OF TGF-BETA1 ON MESANGIAL CELLS WERE INVESTIGATED AT DIFFERENT MOLECULAR LEVELS BY TREATING MESANGIAL CELLS WITH TGF-BETA1 FOR 3 DAYS FOLLOWED BY GENOME-WIDE MIRNA, RNA, DNA METHYLATION, AND H3K27ME3 EXPRESSION PROFILING USING NEXT GENERATION SEQUENCING (NGS). RESULTS: OUR RESULTS PROVIDE THE FIRST COMPREHENSIVE, COMPUTATIONALLY INTEGRATED REPORT OF RNA-SEQ, MIRNA-SEQ, AND EPIGENOMIC ANALYSES ACROSS ALL GENETIC VARIATIONS, CONFIRMING THE OCCURRENCE OF DNA METHYLATION AND H3K27ME3 IN RESPONSE TO TGF-BETA1. OUR FINDINGS SHOW THAT THE EXPRESSION OF KLF7 AND GJA4 ARE INVOLVED IN TGF-BETA1 REGULATED DNA METHYLATION. OUR DATA ALSO PROVIDE EVIDENCE OF THE ASSOCIATION BETWEEN EPIGENETIC CHANGES AND THE EXPRESSION OF GENES CLOSELY RELATED TO TGF-BETA1 REGULATION. CONCLUSION: THIS STUDY HAS ADVANCED OUR CURRENT KNOWLEDGE OF MECHANISMS THAT CONTRIBUTE TO THE EXPRESSION OF TGF-BETA1-REGULATED GENES INVOLVED IN THE PATHOGENESIS OF KIDNEY DISEASE. THE MOLECULAR UNDERPINNINGS OF TGF-BETA1 STIMULATION OF KIDNEY CELLS WAS DETERMINED, THEREBY PROVIDING A ROBUST PLATFORM FOR FURTHER TARGET EXPLORATION. 2018 13 6839 28 [LUNG CANCER AND ITS EPIGENETICS ASSOCIATION WITH CHRONIC OBSTRUCTIVE PULMONARY DISEASE]. LUNG CANCER AND CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) ARE THE LEADING CAUSES OF MORBIDITY AND MORTALITY WORLDWIDE. DEVELOPMENT OF LUNG CANCER INVOLVES BOTH GENETIC AND ENVIRONMENT FACTORS. IN ADDITION TO GENETIC ALTERATIONS, EPIGENETIC MECHANISM IS CLOSELY INVOLVED IN PATHOGENESIS OF LUNG CANCER. CHARACTERIZED BY AN ABNORMAL PERSISTENT INFLAMMATORY RESPONSE TO NOXIOUS ENVIRONMENTAL STIMULATION, COPD HAS SHOWN TO INCREASE THE SUSCEPTIBILITY FOR LUNG TUMORIGENESIS IN PREVIOUS RESEARCH. CURRENT RESEARCH ON EPIGENETICS OF LUNG CANCER AND COPD HAS FOCUSED ON ABERRANT DNA METHYLATION, HISTONE ACETYLATION AND NON-CODING RNAS REGULATION. THE ABERRANT DNA METHYLATION ASSOCIATED WITH LUNG CANCER AND COPD HAS INCLUDED OVEREXPRESSION OF DNA METHYLTRANSFERASE, GLOBAL DNA HYPOMETHYLATION AND DNA HYPERMETHYLATION IN PROMOTER REGIONS, WHILE HISTONE ACETYLATION AND HISTONE METHYLATION ARE THE MAJOR CHANGES FOR HISTONE MODIFICATION, IN WHICH HISTONE ACETYLTRANSFERASES, HISTONE DEACETYLASES, HISTONE METHYLTRANSFERASES AND HISTONE DEMETHYLASES PLAY THE MOST IMPORTANT ROLES. RNA INTERFERENCE AND MICRORNAS ARE BOTH HOT TOPICS OF RESEARCH ON NON-CODING RNAS REGULATION. UNDERSTANDING OF CONCURRENT EPIGENETIC ALTERATIONS IN THE PATHOGENESIS OF LUNG CANCER AND COPD MAY FACILITATE IDENTIFICATION OF SPECIFIC THERAPEUTIC TARGETS AND DEVELOPMENT OF EFFECTIVE TREATMENT. 2013 14 5575 38 ROLE OF MICRORNAS IN SIGNALING PATHWAYS ASSOCIATED WITH THE PATHOGENESIS OF IDIOPATHIC PULMONARY FIBROSIS: A FOCUS ON EPITHELIAL-MESENCHYMAL TRANSITION. IDIOPATHIC PULMONARY FIBROSIS (IPF) IS A CHRONIC AND PROGRESSIVE DISEASE WITH HIGH MORTALITY AND UNCLEAR ETIOLOGY. PREVIOUS EVIDENCE SUPPORTS THAT THE ORIGIN OF THIS DISEASE IS ASSOCIATED WITH EPIGENETIC ALTERATIONS, AGE, AND ENVIRONMENTAL FACTORS. IPF INITIATES WITH CHRONIC EPITHELIAL LUNG INJURIES, FOLLOWED BY BASAL MEMBRANE DESTRUCTION, WHICH PROMOTES THE ACTIVATION OF MYOFIBROBLASTS AND EXCESSIVE SYNTHESIS OF EXTRACELLULAR MATRIX (ECM) PROTEINS, AS WELL AS EPITHELIAL-MESENCHYMAL TRANSITION (EMT). DUE TO MIRNAS' ROLE AS REGULATORS OF APOPTOSIS, PROLIFERATION, DIFFERENTIATION, AND CELL-CELL INTERACTION PROCESSES, SOME STUDIES HAVE INVOLVED MIRNAS IN THE BIOGENESIS AND PROGRESSION OF IPF. IN THIS CONTEXT, THE ANALYSIS AND DISCUSSION OF THE PROBABLE ASSOCIATION OF MIRNAS WITH THE SIGNALING PATHWAYS INVOLVED IN THE DEVELOPMENT OF IPF WOULD IMPROVE OUR KNOWLEDGE OF THE ASSOCIATED MOLECULAR MECHANISMS, THEREBY FACILITATING ITS EVALUATION AS A THERAPEUTIC TARGET FOR THIS SEVERE LUNG DISEASE. IN THIS WORK, THE MOST RECENT PUBLICATIONS EVALUATING THE ROLE OF MIRNAS AS REGULATORS OR ACTIVATORS OF SIGNAL PATHWAYS ASSOCIATED WITH THE PATHOGENESIS OF IPF WERE ANALYZED. THE SEARCH IN PUBMED WAS MADE USING THE FOLLOWING TERMS: "MIRNAS AND IDIOPATHIC PULMONARY FIBROSIS (IPF)"; "MIRNAS AND IPF AND SIGNALING PATHWAYS (SP)"; AND "MIRNAS AND IPF AND SP AND IPF PATHOGENESIS". ADDITIONALLY, WE FOCUS MAINLY ON THOSE WORKS WHERE THE SIGNALING PATHWAYS INVOLVED WITH EMT, FIBROBLAST DIFFERENTIATION, AND SYNTHESIS OF ECM COMPONENTS WERE ASSESSED. FINALLY, THE IMPORTANCE AND SIGNIFICANCE OF MIRNAS AS POTENTIAL THERAPEUTIC OR DIAGNOSTIC TOOLS FOR THE TREATMENT OF IPF ARE DISCUSSED. 2022 15 4228 23 METHYLATION OF INFLAMMATORY CELLS IN LUNG DISEASES. THIS CHAPTER OVERVIEWS ROLES OF DNA METHYLATION IN INFLAMMATORY CELL BIOLOGY WITH THE FOCUSES ON LYMPHOCYTES AND MACROPHAGES/MONOCYTES IN LUNG DISEASES, ALTHOUGH THE MOLECULAR MECHANISMS BY WHICH TARGET GENES ARE METHYLATED AND REGULATED IN LUNG DISEASES REMAIN UNCLEAR. MOST OF EPIGENETIC STUDIES ON DNA METHYLATION OF TARGET GENES IN LUNG DISEASES MAINLY DEMONSTRATED THE CORRELATION OF DNA METHYLATION OF TARGET GENES WITH THE LEVELS OF OTHER CORRESPONDING FACTORS, WITH THE SPECIFICITY OF CLINICAL PHENOMES, AND WITH THE SEVERITY OF LUNG DISEASES. THERE IS AN URGENT NEED TO IDENTIFY AND VALIDATE THE SPECIFICITY AND REGULATORY MECHANISMS OF INFLAMMATORY CELL EPIGENETICS IN DEPTH. THE EPIGENETIC HETEROGENEITY AMONG DIFFERENT SUBSETS OF T CELLS AND AMONG PROMOTERS OR NON-PROMOTERS OF TARGET GENES SHOULD BE FURTHERMORE CLARIFIED IN ACUTE OR CHRONIC LUNG DISEASES AND CANCERS. THE HYPER/HYPO-METHYLATION AND MODIFICATIONS OF CHROMOSOL AND EXTRACHROMOSOMAL DNA MAY RESULT IN ALTERNATIONS IN PROTEINS WITHIN INFLAMMATORY CELLS, WHICH CAN BE IDENTIFIED AS DISEASE-SPECIFIC BIOMARKERS AND THERAPEUTIC TARGETS. 2020 16 2026 30 EPIGENETIC CHANGES IN BONE MARROW PROGENITOR CELLS INFLUENCE THE INFLAMMATORY PHENOTYPE AND ALTER WOUND HEALING IN TYPE 2 DIABETES. CLASSICALLY ACTIVATED (M1) MACROPHAGES ARE KNOWN TO PLAY A ROLE IN THE DEVELOPMENT OF CHRONIC INFLAMMATION ASSOCIATED WITH IMPAIRED WOUND HEALING IN TYPE 2 DIABETES (T2D); HOWEVER, THE MECHANISM RESPONSIBLE FOR THE DOMINANT PROINFLAMMATORY (M1) MACROPHAGE PHENOTYPE IN T2D WOUNDS IS UNKNOWN. SINCE EPIGENETIC ENZYMES CAN DIRECT MACROPHAGE PHENOTYPES, WE ASSESSED THE ROLE OF HISTONE METHYLATION IN BONE MARROW (BM) STEM/PROGENITOR CELLS IN THE PROGRAMMING OF MACROPHAGES TOWARD A PROINFLAMMATORY PHENOTYPE. WE HAVE FOUND THAT A REPRESSIVE HISTONE METHYLATION MARK, H3K27ME3, IS DECREASED AT THE PROMOTER OF THE IL-12 GENE IN BM PROGENITORS AND THIS EPIGENETIC SIGNATURE IS PASSED DOWN TO WOUND MACROPHAGES IN A MURINE MODEL OF GLUCOSE INTOLERANCE (DIET-INDUCED OBESE). THESE EPIGENETICALLY "PREPROGRAMMED" MACROPHAGES RESULT IN POISED MACROPHAGES IN PERIPHERAL TISSUE AND NEGATIVELY IMPACT WOUND REPAIR. WE FOUND THAT IN DIABETIC CONDITIONS THE H3K27 DEMETHYLASE JMJD3 DRIVES IL-12 PRODUCTION IN MACROPHAGES AND THAT IL-12 PRODUCTION CAN BE MODULATED BY INHIBITING JMJD3. USING HUMAN T2D TISSUE AND MURINE MODELS, WE HAVE IDENTIFIED A PREVIOUSLY UNRECOGNIZED MECHANISM BY WHICH MACROPHAGES ARE PROGRAMMED TOWARD A PROINFLAMMATORY PHENOTYPE, ESTABLISHING A PATTERN OF UNRESTRAINED INFLAMMATION ASSOCIATED WITH NONHEALING WOUNDS. HENCE, HISTONE DEMETHYLASE INHIBITOR-BASED THERAPY MAY REPRESENT A NOVEL TREATMENT OPTION FOR DIABETIC WOUNDS. 2015 17 4661 23 NEW ASPECTS OF THE EPIGENETIC REGULATION OF EMT RELATED TO PULMONARY FIBROSIS. PULMONARY FIBROSIS IS A CHRONIC AND PROGRESSIVE FIBROTIC DISEASE THAT RESULTS IN IMPAIRED GAS EXCHANGE, VENTILATION, AND EVENTUAL DEATH. THE PRO-FIBROTIC ENVIRONMENT IS INSTIGATED BY VARIOUS FACTORS, LEADING TO THE TRANSFORMATION OF EPITHELIAL CELLS INTO MYOFIBROBLASTS AND/OR FIBROBLASTS THAT TRIGGER FIBROSIS. EPITHELIAL MESENCHYMAL TRANSITION (EMT) IS A BIOLOGICAL PROCESS THAT PLAYS A CRITICAL ROLE IN THE PATHOGENESIS OF PULMONARY FIBROSIS. EPIGENETIC REGULATION OF TISSUE-STROMAL CROSSTALK INVOLVING DNA METHYLATION, HISTONE MODIFICATIONS, NON-CODING RNA, AND CHROMATIN REMODELING PLAYS A KEY ROLE IN THE CONTROL OF EMT. THE REVIEW INVESTIGATES THE EPIGENETIC REGULATION OF EMT AND ITS SIGNIFICANCE IN PULMONARY FIBROSIS. 2023 18 5975 27 TET1 IS AN IMPORTANT TRANSCRIPTIONAL ACTIVATOR OF TNFALPHA EXPRESSION IN MACROPHAGES. ACTIVATION OF MACROPHAGES AND OVEREXPRESSION OF TNFALPHA IS ASSOCIATED WITH THE PATHOGENESIS OF CHRONIC INFLAMMATORY DISEASES. HOWEVER, THE MECHANISMS LEADING TO TNFALPHA OVEREXPRESSION ARE STILL UNKNOWN. 5-METHYLOCYTOSINE (5-MC) IS AN EPIGENETIC MODIFICATION THAT IS ASSOCIATED WITH SILENCED GENES. RECENT STUDIES SHOWED THAT IT IS CONVERTED TO 5-HYDROXYLMETHYLOCYTOSINE (5-HMC) AND REACTIVATES GENE EXPRESSION THROUGH THE ACTION OF THE FAMILY OF TEN-ELEVEN-TRANSLOCATION (TET1-3) ENZYMES. IN THIS STUDY, WE SHOW THAT 5-HMC LEVELS ARE INCREASED GLOBALLY AND SPECIFICALLY IN THE TNFALPHA PROMOTER DURING THE DIFFERENTIATION OF MONOCYTES TO MACROPHAGES. IN ADDITION, THE LEVELS OF 5-HMC ARE INCREASED UPON LPS STIMULATION OF MACROPHAGES. FURTHERMORE, CRIPSR STABLE KNOCKOUT OF TET1 DECREASES THE EXPRESSION OF TNFALPHA AND OTHER PRO-INFLAMMATORY CYTOKINES. IN CONCLUSION, WE SHOWED THAT TET1 CONTRIBUTES TO THE ACTIVATION OF MACROPHAGES POSSIBLY THROUGH REGULATION OF 5-HYDROXYMETHYLATION IN THE PROMOTER OF PRO-INFLAMMATORY CYTOKINE GENES. THE TET1 ENZYME COULD BE A PROMISING THERAPEUTIC TARGET TO INHIBIT THE PERSISTENT INFLAMMATION CAUSED BY MACROPHAGES IN CHRONIC INFLAMMATORY DISEASES. 2019 19 5418 41 REGULATION OF DNA METHYLATION SIGNATURES ON NF-KAPPAB AND STAT3 PATHWAY GENES AND TET ACTIVITY IN CIGARETTE SMOKE EXTRACT-CHALLENGED CELLS/COPD EXACERBATION MODEL IN VITRO. BACKGROUND: CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) IS A GLOBAL HEALTH PROBLEM. CURRENTLY, THERE IS A LACK OF KNOWLEDGE ABOUT THE PATHOBIOLOGY OF THIS DISEASE AND AVAILABLE THERAPIES ARE INEFFECTIVE. CIGARETTE SMOKING IS THE LEADING CAUSE OF COPD; HOWEVER, NOT ALL SMOKERS DEVELOP COPD. EXACERBATIONS OF COPD CAUSED BY MICROBES ARE COMMON AND DETRIMENTAL. APPROXIMATELY 20-50% OF PATIENT EXACERBATIONS ARE CAUSED BY BACTERIAL COLONIZATION IN THE LOWER AIRWAYS. IT IS GENERALLY ACCEPTED THAT EPIGENETIC MECHANISMS, ESPECIALLY DNA METHYLATION, PLAY AN IMPORTANT ROLE DURING PROGRESSION OF COPD. THUS, WE HYPOTHESIZED THAT DNA METHYLATION PATTERNS VARY SIGNIFICANTLY FOLLOWING SMOKE EXPOSURE AND DURING EXACERBATIONS CAUSED BY BACTERIAL INFECTIONS. TO TEST OUR HYPOTHESIS, WE USED AN IN VITRO STUDY MODEL THAT MIMICS COPD EXACERBATIONS AND PERFORMED EXTENSIVE STUDIES TO UNDERSTAND THE ROLE OF CPG PROMOTER METHYLATION OF NF-KAPPAB AND STAT3-MEDIATED PATHWAY GENES. BOTH NF-KAPPAB AND STAT3 TRANSCRIPTION FACTORS PLAY CRITICAL ROLES IN ORCHESTRATING INFLAMMATORY RESPONSES DURING CIGARETTE SMOKE EXPOSURE. IN BRIEF, HUMAN LUNG ADENOCARCINOMA CELLS WITH TYPE II ALVEOLAR EPITHELIUM CHARACTERISTICS (A549) WERE CHALLENGED WITH CIGARETTE SMOKE EXTRACT (CSE) OR DMSO (CONTROL) FOLLOWED BY A 3-H CHALLENGE WITH BACTERIAL LIPOPOLYSACCHARIDE (LPS; FROM PSEUDOMONAS AERUGINOSA) PRIOR TO THE TERMINATION OF CSE EXPOSURE (COPD EXACERBATION GROUP). THE PRODUCTION OF CYTOKINES/CHEMOKINES, REGULATION OF TRANSCRIPTION FACTORS, AND DNA METHYLATION OF SPECIFIC GENES WERE THEN ASSESSED. WE ALSO STUDIED CHANGES IN THE EXPRESSION AND ACTIVITY OF TEN-ELEVEN TRANSLOCASES (TETS), THE ENZYMES RESPONSIBLE FOR DNA DEMETHYLATION, AND ASSESSED THEIR ROLE IN REGULATING DNA METHYLATION IN THE CSE-CHALLENGED GROUP. RESULTS: THERE WAS A SIGNIFICANT INCREASE IN THE RELEASE OF CYTOKINES/CHEMOKINES (IL-8, MCP-1, IL-6 AND CCL5) IN THE COPD EXACERBATION GROUP AS COMPARED TO THE CONTROL GROUP. HYPOMETHYLATION OF NF-KAPPAB-MEDIATED PATHWAY GENES CORRELATED WITH THEIR INDUCTION IN OUR COPD EXACERBATION STUDY MODEL. FURTHER, WE OBSERVED AN IMPORTANT ROLE OF TET1/2 IN REGULATING THE DNA METHYLATION OF NF-KAPPAB, STAT3, IKK, AND NIK GENES AND CYTOKINE/CHEMOKINE PRODUCTION BY A549 CELLS DURING CSE CHALLENGE. CONCLUSIONS: STUDIES TO FURTHER DEFINE THE ROLE OF TETS IN CSE-MEDIATED EPIGENETIC REGULATION MAY LEAD TO THE DEVELOPMENT OF BETTER AND MORE EFFECTIVE THERAPEUTIC INTERVENTION STRATEGIES FOR COPD. 2020 20 1269 33 CYTOSINE METHYLATION CHANGES IN ENHANCER REGIONS OF CORE PRO-FIBROTIC GENES CHARACTERIZE KIDNEY FIBROSIS DEVELOPMENT. BACKGROUND: ONE IN ELEVEN PEOPLE IS AFFECTED BY CHRONIC KIDNEY DISEASE, A CONDITION CHARACTERIZED BY KIDNEY FIBROSIS AND PROGRESSIVE LOSS OF KIDNEY FUNCTION. EPIDEMIOLOGICAL STUDIES INDICATE THAT ADVERSE INTRAUTERINE AND POSTNATAL ENVIRONMENTS HAVE A LONG-LASTING ROLE IN CHRONIC KIDNEY DISEASE DEVELOPMENT. EPIGENETIC INFORMATION REPRESENTS A PLAUSIBLE CARRIER FOR MEDIATING THIS PROGRAMMING EFFECT. HERE WE DEMONSTRATE THAT GENOME-WIDE CYTOSINE METHYLATION PATTERNS OF HEALTHY AND CHRONIC KIDNEY DISEASE TUBULE SAMPLES OBTAINED FROM PATIENTS SHOW SIGNIFICANT DIFFERENCES. RESULTS: WE IDENTIFY DIFFERENTIALLY METHYLATED REGIONS AND VALIDATE THESE IN A LARGE REPLICATION DATASET. THE DIFFERENTIALLY METHYLATED REGIONS ARE RARELY OBSERVED ON PROMOTERS, BUT MOSTLY OVERLAP WITH PUTATIVE ENHANCER REGIONS, AND THEY ARE ENRICHED IN CONSENSUS BINDING SEQUENCES FOR IMPORTANT RENAL TRANSCRIPTION FACTORS. THIS INDICATES THEIR IMPORTANCE IN GENE EXPRESSION REGULATION. A CORE SET OF GENES THAT ARE KNOWN TO BE RELATED TO KIDNEY FIBROSIS, INCLUDING GENES ENCODING COLLAGENS, SHOW CYTOSINE METHYLATION CHANGES CORRELATING WITH DOWNSTREAM TRANSCRIPT LEVELS. CONCLUSIONS: OUR REPORT RAISES THE POSSIBILITY THAT EPIGENETIC DYSREGULATION PLAYS A ROLE IN CHRONIC KIDNEY DISEASE DEVELOPMENT VIA INFLUENCING CORE PRO-FIBROTIC PATHWAYS AND CAN AID THE DEVELOPMENT OF NOVEL BIOMARKERS AND FUTURE THERAPEUTICS. 2013