1 5099 104 PM2.5 EXPOSURE EXACERBATES ALLERGIC RHINITIS IN MICE BY INCREASING DNA METHYLATION IN THE IFN-GAMMA GENE PROMOTER IN CD4+T CELLS VIA THE ERK-DNMT PATHWAY. ALLERGIC RHINITIS (AR) IS A COMMON CHRONIC INFLAMMATORY DISEASE THAT HAS A SIGNIFICANT IMPACT ON THE QUALITY OF LIFE OF PATIENTS. OUR PREVIOUS STUDY SUGGESTED THAT PM2.5 MIGHT AFFECT PEDIATRIC AR THROUGH EPIGENETIC REGULATION, BUT THE UNDERLYING MECHANISMS REMAINED UNCLEAR. IN THIS STUDY, AN EXPERIMENTAL MURINE AR MODEL WAS CREATED, AND THE NASAL SYMPTOMS, PATHOLOGICAL CHANGES, THE DNA METHYLATION LEVEL OF THE IFN-GAMMA GENE PROMOTER AND ACTIVATION OF THE ERK-DNMT PATHWAY WERE EVALUATED AFTER TREATMENT WITH PM2.5. OUR RESULTS SHOWED THAT PM2.5 EXPOSURE LED TO MORE SEVERE SYMPTOMS OF AR IN MICE. IN ADDITION, PM2.5 EXPOSURE SIGNIFICANTLY DECREASED THE PERCENTAGE OF TH1 T CELLS IN THE AR GROUP, AND THIS CHANGE WAS CORRELATED WITH INCREASED DNA METHYLATION OF THE IFN-GAMMA GENE PROMOTER IN CD4 + T CELLS (R=-0.916, P = 0.029). IN ADDITION, PM2.5 EXPOSURE INCREASED THE ACTIVATION OF THE ERK-DNMT PATHWAY IN CD4+ T CELLS, AND INHIBITING THIS EFFECT RESCUED THE POLARIZATION OF THE TH1/TH2 BALANCE TOWARD TH2, THEREBY DECREASING THE RISK OF AR. OUR FINDINGS DEMONSTRATE THAT PM2.5 EXPOSURE COULD EXACERBATE AR BY INCREASING THE DNA METHYLATION OF THE IFN-GAMMA GENE PROMOTER IN CD4 + T CELLS VIA THE ERK-DNMT PATHWAY, AND THESE EFFECTS WERE RESCUED WHEN THE ERK-DNMT PATHWAY WAS INHIBITED. 2019 2 1584 21 DNA METHYLATION PROFILES OF SELECTED PRO-INFLAMMATORY CYTOKINES IN ALZHEIMER DISEASE. BY MEANS OF FUNCTIONAL GENOMICS ANALYSIS, WE RECENTLY DESCRIBED THE MRNA EXPRESSION PROFILES OF VARIOUS GENES INVOLVED IN THE NEUROINFLAMMATORY RESPONSE IN THE BRAINS OF SUBJECTS WITH LATE-ONSET ALZHEIMER DISEASE (LOAD). SOME OF THESE GENES, NAMELY INTERLEUKIN (IL)-1BETA AND IL-6, SHOWED DISTINCT EXPRESSION PROFILES WITH PEAK EXPRESSION DURING THE FIRST STAGES OF THE DISEASE AND CONTROL-LIKE LEVELS AT LATER STAGES. IL-1BETA AND IL-6 GENES ARE MODULATED BY DNA METHYLATION IN DIFFERENT CHRONIC AND DEGENERATIVE DISEASES; IT IS ALSO WELL KNOWN THAT LOAD MAY HAVE AN EPIGENETIC BASIS. INDEED, WE AND OTHERS HAVE PREVIOUSLY REPORTED GENE-SPECIFIC DNA METHYLATION ALTERATIONS IN LOAD AND IN RELATED ANIMAL MODELS. BASED ON THESE DATA, WE STUDIED THE DNA METHYLATION PROFILES, AT SINGLE CYTOSINE RESOLUTION, OF IL-1BETA AND IL-6 5'-FLANKING REGION BY BISULPHITE MODIFICATION IN THE CORTEX OF HEALTHY CONTROLS AND LOAD PATIENTS AT 2 DIFFERENT DISEASE STAGES: BRAAK I-II/A AND BRAAK V-VI/C. OUR ANALYSIS PROVIDES EVIDENCE THAT NEUROINFLAMMATION IN LOAD IS ASSOCIATED WITH (AND POSSIBLY MEDIATED BY) EPIGENETIC MODIFICATIONS. 2017 3 6794 32 [EFFECT OF BENZO(A)PYRENE ON THE EXPRESSION OF AHR-REGULATED MICRORNA IN FEMALE AND MALE RAT LUNGS]. SMOKING IS THE MAIN RISK FACTOR FOR LUNG CANCER, MAINLY DUE TO PRESENCE OF NITROSAMINES AND POLYCYCLIC AROMATIC HYDROCARBONS, INCLUDING BENZO[A]PYRENE (BP) IN TOBACCO SMOKE COMPOSITION. THE GENOTOXIC EFFECT OF BP IS BASED ON THE HIGH DNA-BINDING ABILITY OF ITS METABOLITES, WHILE THE EPIGENETIC EFFECTS ARE MEDIATED BY A CHANGE IN THE EXPRESSION OF CANCER RELATED GENES OR REGULATORY RNAS. IT HAS BEEN SHOWN THAT WOMEN HAVE A HIGHER RISK TO DEVELOP LUNG CANCER UPON SMOKING RATHER THAN MEN. WE HYPOTHESIZED THAT CROSSTALK BETWEEN SIGNALING PATHWAYS ACTIVATED BY BP AND ESTROGENS COULD UNDERLIE THE SEX-DEPENDENT DIFFERENCES IN MIRNAS EXPRESSION. TO TEST THIS HYPOTHESIS, MALE AND FEMALE RATS WERE SUBJECTED TO SHORT-TERM OR LONG-TERM BP EXPOSURE. USING IN SILICO ANALYSIS, MIRNAS CONTAINING THE ER- AND AHR-BINDING SITES IN THE PROMOTERS OF THE GENES (OR HOST GENES) WERE SELECTED. DURING CHRONIC EXPOSURE OF BP THE EXPRESSION OF MIR-22-3P, -29A-3P, -126A-3P, -193B-5P IN THE LUNGS OF MALE RATS WERE SIGNIFICANTLY INCREASED, WHILE THE LEVEL OF MIRNA-483-3P WERE DECREASED. EXPRESSION OF MIRNA-483-3P WAS UP-REGULATED DURING CHRONIC BP EXPOSURE IN THE LUNGS OF FEMALE RATS AND THE LEVELS OF OTHER STUDIED MIRNAS WERE UNCHANGED. IN TURN, CHANGES IN THE EXPRESSION OF MIRNAS WERE FOLLOWED BY CHANGES IN THE EXPRESSION OF THEIR TARGET GENES, INCLUDING PTEN, EMP2, IGF1, ITGA6, SLC34A2, AND THE OBSERVED CHANGES IN FEMALE AND MALE RAT LUNGS WERE VARIED. THUS, OUR RESULTS SUGGEST THAT SEX-DEPENDENT EPIGENETIC EFFECTS OF BP MAY BE BASED ON DIFFERENT EXPRESSION OF AHR- AND ER- REGULATED MIRNAS. 2020 4 419 32 ANDROGEN AXIS IN PROSTATE CANCER. ENDOCRINE THERAPY FOR ADVANCED PROSTATE CANCER IS BASED ON ANDROGEN ABLATION OR BLOCKADE OF THE ANDROGEN RECEPTOR (AR). AR ACTION IN PROSTATE CANCER HAS BEEN INVESTIGATED IN A NUMBER OF CELL LINES, THEIR DERIVATIVES, AND TRANSGENIC ANIMALS. AR EXPRESSION IS HETEROGENOUS IN PROSTATE CANCER IN VIVO; IT COULD BE DETECTED IN MOST PRIMARY TUMORS AND THEIR METASTASES. HOWEVER, SOME CELLS LACK THE AR BECAUSE OF EPIGENETIC CHANGES IN THE GENE PROMOTER. AR EXPRESSION INCREASES AFTER CHRONIC ANDROGEN ABLATION IN VITRO. IN SEVERAL XENOGRAFTS, AR UPREGULATION IS THE MOST CONSISTENT CHANGE IDENTIFIED DURING PROGRESSION TOWARDS THERAPY RESISTANCE. IN CONTRAST, THE AR PATHWAY MAY BE BY-PASSED DURING CHRONIC TREATMENT WITH A NONSTEROIDAL ANTI-ANDROGEN. AR SENSITIVITY IN PROSTATE CANCER INCREASES AS A RESULT OF ACTIVATION OF THE RAS/MITOGEN-ACTIVATED PROTEIN KINASE PATHWAY. ONE OF THE MAJOR DIFFICULTIES IN ENDOCRINE THERAPY FOR PROSTATE CANCER IS ACQUISITION OF AGONISTIC PROPERTIES OF AR ANTAGONISTS OBSERVED IN THE PRESENCE OF MUTATED AR. ENHANCEMENT OF AR FUNCTION BY ASSOCIATED COACTIVATOR PROTEINS HAS BEEN EXTENSIVELY INVESTIGATED. COFACTORS SRC-1, RAC3, P300/CBP, TIF-2, AND TIP60 ARE UPREGULATED IN ADVANCED PROSTATE CANCER. MOST STUDIES ON LIGAND-INDEPENDENT ACTIVATION OF THE AR ARE FOCUSED ON HER-2/NEU AND INTERLEUKIN-6 (IL-6). ON THE BASIS OF STUDIES THAT SHOWED OVEREXPRESSION AND ACTIVATION OF THE AR IN ADVANCED PROSTATE CANCER, IT WAS SUGGESTED THAT NOVEL THERAPIES THAT REDUCE AR EXPRESSION WILL PROVIDE A BENEFIT TO PATIENTS. THERE IS EXPERIMENTAL EVIDENCE SHOWING THAT PROSTATE TUMOR GROWTH IN VITRO AND IN VIVO IS INHIBITED FOLLOWING ADMINISTRATION OF CHEMOPREVENTIVE DRUGS OR ANTISENSE OLIGONUCLEOTIDES THAT DOWNREGULATE AR MRNA AND PROTEIN EXPRESSION. 2006 5 2864 28 FUNCTION OF PM2.5 IN THE PATHOGENESIS OF LUNG CANCER AND CHRONIC AIRWAY INFLAMMATORY DISEASES. PREVIOUS RESEARCH HAS IDENTIFIED THAT AIR POLLUTION IS ASSOCIATED WITH VARIOUS RESPIRATORY DISEASES, BUT FEW STUDIES HAVE INVESTIGATED THE FUNCTION SERVED BY PARTICULATE MATTER 2.5 (PM2.5) IN THESE DISEASES. PM2.5 IS KNOWN TO CAUSE EPIGENETIC AND MICROENVIRONMENTAL ALTERATIONS IN LUNG CANCER, INCLUDING TUMOR-ASSOCIATED SIGNALING PATHWAY ACTIVATION MEDIATED BY MICRORNA DYSREGULATION, DNA METHYLATION, AND INCREASED LEVELS OF CYTOKINES AND INFLAMMATORY CELLS. AUTOPHAGY AND APOPTOSIS OF TUMOR CELLS MAY ALSO BE DETECTED IN LUNG CANCER ASSOCIATED WITH PM2.5 EXPOSURE. A NUMBER OF MECHANISMS ARE INVOLVED IN TRIGGERING AND AGGRAVATING ASTHMA AND COPD, INCLUDING PM2.5-INDUCED CYTOKINE RELEASE AND OXIDATIVE STRESS. THE PRESENT REVIEW IS AN OVERVIEW OF THE UNDERLYING MOLECULAR MECHANISMS OF PM2.5-INDUCED PATHOGENESIS IN LUNG CANCER AND CHRONIC AIRWAY INFLAMMATORY DISEASES. 2018 6 3468 36 HYPOXIA-INDUCED DNA HYPERMETHYLATION IN HUMAN PULMONARY FIBROBLASTS IS ASSOCIATED WITH THY-1 PROMOTER METHYLATION AND THE DEVELOPMENT OF A PRO-FIBROTIC PHENOTYPE. BACKGROUND: PULMONARY FIBROSIS IS A DEBILITATING AND LETHAL DISEASE WITH NO EFFECTIVE TREATMENT OPTIONS. UNDERSTANDING THE PATHOLOGICAL PROCESSES AT PLAY WILL DIRECT THE APPLICATION OF NOVEL THERAPEUTIC AVENUES. HYPOXIA HAS BEEN IMPLICATED IN THE PATHOGENESIS OF PULMONARY FIBROSIS YET THE PRECISE MECHANISM BY WHICH IT CONTRIBUTES TO DISEASE PROGRESSION REMAINS TO BE FULLY ELUCIDATED. IT HAS BEEN SHOWN THAT CHRONIC HYPOXIA CAN ALTER DNA METHYLATION PATTERNS IN TUMOUR-DERIVED CELL LINES. THIS EPIGENETIC ALTERATION CAN INDUCE CHANGES IN CELLULAR PHENOTYPE WITH PROMOTER METHYLATION BEING ASSOCIATED WITH GENE SILENCING. OF PARTICULAR RELEVANCE TO IDIOPATHIC PULMONARY FIBROSIS (IPF) IS THE OBSERVATION THAT THY-1 PROMOTER METHYLATION IS ASSOCIATED WITH A MYOFIBROBLAST PHENOTYPE WHERE LOSS OF THY-1 OCCURS ALONGSIDE INCREASED ALPHA SMOOTH MUSCLE ACTIN (ALPHA-SMA) EXPRESSION. THE INITIAL AIM OF THIS STUDY WAS TO DETERMINE WHETHER HYPOXIA REGULATES DNA METHYLATION IN NORMAL HUMAN LUNG FIBROBLASTS (CCD19LU). AS IT HAS BEEN REPORTED THAT HYPOXIA SUPPRESSES THY-1 EXPRESSION DURING LUNG DEVELOPMENT WE ALSO STUDIED THE EFFECT OF HYPOXIA ON THY-1 PROMOTER METHYLATION AND GENE EXPRESSION. METHODS: CCD19LU WERE GROWN FOR UP TO 8 DAYS IN HYPOXIA AND ASSESSED FOR GLOBAL CHANGES IN DNA METHYLATION USING FLOW CYTOMETRY. REAL-TIME PCR WAS USED TO QUANTIFY EXPRESSION OF THY-1, ALPHA-SMA, COLLAGEN I AND III. GENOMIC DNA WAS BISULPHITE TREATED AND METHYLATION SPECIFIC PCR (MSPCR) WAS USED TO EXAMINE THE METHYLATION STATUS OF THE THY-1 PROMOTER. RESULTS: SIGNIFICANT GLOBAL HYPERMETHYLATION WAS DETECTED IN HYPOXIC FIBROBLASTS RELATIVE TO NORMOXIC CONTROLS AND WAS ACCOMPANIED BY INCREASED EXPRESSION OF MYOFIBROBLAST MARKERS. THY-1 MRNA EXPRESSION WAS SUPPRESSED IN HYPOXIC CELLS, WHICH WAS RESTORED WITH THE DEMETHYLATING AGENT 5-AZA-2'-DEOXYCYTIDINE. MSPCR REVEALED THAT THY-1 BECAME METHYLATED FOLLOWING FIBROBLAST EXPOSURE TO 1% O2. CONCLUSION: THESE DATA SUGGEST THAT GLOBAL AND GENE-SPECIFIC CHANGES IN DNA METHYLATION MAY PLAY AN IMPORTANT ROLE IN FIBROBLAST FUNCTION IN HYPOXIA. 2012 7 2395 33 EPIGENETIC REPROGRAMMING IN MIST1(-/-) MICE PREDICTS THE MOLECULAR RESPONSE TO CERULEIN-INDUCED PANCREATITIS. GENE EXPRESSION IS AFFECTED BY MODIFICATIONS TO HISTONE CORE PROTEINS WITHIN CHROMATIN. CHANGES IN THESE MODIFICATIONS, OR EPIGENETIC REPROGRAMMING, CAN DICTATE CELL FATE AND PROMOTE SUSCEPTIBILITY TO DISEASE. THE GOAL OF THIS STUDY WAS TO DETERMINE THE EXTENT OF EPIGENETIC REPROGRAMMING IN RESPONSE TO CHRONIC STRESS THAT OCCURS FOLLOWING ABLATION OF MIST1 (MIST1(-/-) ), WHICH IS REPRESSED IN PANCREATIC DISEASE. CHROMATIN IMMUNOPRECIPITATION FOR TRIMETHYLATION OF LYSINE RESIDUE 4 ON HISTONE 3 (H3K4ME3) IN PURIFIED ACINAR CELLS FROM WILD TYPE AND MIST1(-/-) MICE WAS FOLLOWED BY NEXT GENERATION SEQUENCING (CHIP-SEQ) OR CHIP-QPCR. H3K4ME3-ENRICHED GENES WERE ASSESSED FOR EXPRESSION BY QRT-PCR IN PANCREATIC TISSUE BEFORE AND AFTER INDUCTION OF CERULEIN-INDUCED PANCREATITIS. WHILE MOST OF H3K4ME3-ENRICHMENT IS RESTRICTED TO TRANSCRIPTIONAL START SITES, >25% OF ENRICHMENT SITES ARE FOUND WITHIN, DOWNSTREAM OR BETWEEN ANNOTATED GENES. LESS THAN 10% OF THESE SITES WERE ALTERED IN MIST1(-/-) ACINI, WITH MOST CHANGES IN H3K4ME3 ENRICHMENT NOT REFLECTING ALTERED GENE EXPRESSION. INGENUITY PATHWAY ANALYSIS OF GENES DIFFERENTIALLY-ENRICHED FOR H3K4ME3 REVEALED AN ASSOCIATION WITH PANCREATITIS AND PANCREATIC DUCTAL ADENOCARCINOMA IN MIST1(-/-) TISSUE. MOST OF THESE GENES WERE NOT DIFFERENTIALLY EXPRESSED BUT SEVERAL WERE READILY INDUCED BY ACUTE EXPERIMENTAL PANCREATITIS, WITH SIGNIFICANTLY INCREASED EXPRESSION IN MIST1(-/-) TISSUE RELATIVE TO WILD TYPE MICE. WE SUGGEST THAT THE CHRONIC CELL STRESS OBSERVED IN THE ABSENCE OF MIST1 RESULTS IN EPIGENETIC REPROGRAMMING OF GENES INVOLVED IN PROMOTING PANCREATITIS TO A POISED STATE, THEREBY INCREASING THE SENSITIVITY TO EVENTS THAT PROMOTE DISEASE. 2014 8 5269 35 PROMOTER DNA METHYLATION CONTRIBUTES TO HUMAN BETA-DEFENSIN-1 DEFICIENCY IN ATOPIC DERMATITIS. ATOPIC DERMATITIS (AD) IS A CHRONIC INFLAMMATORY SKIN DISEASE CAUSED BY EPIDERMAL BARRIER DYSFUNCTION AND DYSREGULATION OF INNATE AND ADAPTIVE IMMUNITY. EPIGENETIC REGULATION OF HUMAN BETA-DEFENSIN-1 (HBD-1) MIGHT BE ASSOCIATED WITH A VARIETY OF DEFECTS IN THE INNATE IMMUNE SYSTEM DURING AD PATHOGENESIS. WE INVESTIGATED THE POSSIBLE MECHANISM OF DECREASED HBD-1 GENE EXPRESSION IN AD AND DEMONSTRATED THE RESTORATION OF HBD-1 TRANSCRIPTION IN UNDIFFERENTIATED NORMAL HUMAN EPIDERMAL KERATINOCYTE CELLS AFTER TREATMENT WITH A DNA METHYLTRANSFERASE INHIBITOR. WE ALSO CONDUCTED AN IN VITRO METHYLATED REPORTER ASSAY USING A REPORTER CONTAINING 14 CPG SITES. METHYLATION OF THE 14 CPG SITES WITHIN THE HBD-1 5' REGION RESULTED IN AN APPROXIMATELY 86% REDUCTION IN PROMOTER ACTIVITY AND AFFECTED HBD-1 TRANSCRIPTIONAL REGULATION. WE THEN COMPARED METHYLATION FREQUENCIES AT CPG 3 AND CPG 4 BETWEEN NON-LESIONAL AND LESIONAL EPIDERMIS SAMPLES OF PATIENTS WITH SEVERE AD AND BETWEEN THESE PAIRED TISSUES AND HEALTHY CONTROL EPIDERMIS FROM NORMAL VOLUNTEERS WITHOUT AD HISTORY. BISULFITE PYROSEQUENCING DATA SHOWED SIGNIFICANTLY HIGHER METHYLATION FREQUENCIES AT THE CPG 3 AND 4 SITES IN AD LESIONAL SAMPLES THAN IN NON-LESIONAL AD SKIN AND NORMAL SKIN SAMPLES (P < 0.05). THESE RESULTS SUGGEST THAT THE DNA METHYLATION SIGNATURE OF HBD-1 IS A NOVEL DIAGNOSTIC/PROGNOSTIC MARKER AND A PROMISING THERAPEUTIC TARGET FOR THE COMPROMISED STRATUM CORNEUM BARRIER ATTRIBUTED TO HBD-1 DEFICIENCY. 2018 9 1117 30 COMPARATIVE AND EXPERIMENTAL STUDIES ON THE GENES ALTERED BY CHRONIC HYPOXIA IN HUMAN BRAIN MICROENDOTHELIAL CELLS. BACKGROUND : HYPOXIA INDUCIBLE FACTOR 1 ALPHA (HIF1A) IS A MASTER REGULATOR OF ACUTE HYPOXIA; HOWEVER, WITH CHRONIC HYPOXIA, HIF1A LEVELS RETURN TO THE NORMOXIC LEVELS. IMPORTANTLY, THE GENES THAT ARE INVOLVED IN THE CELL SURVIVAL AND VIABILITY UNDER CHRONIC HYPOXIA ARE NOT KNOWN. THEREFORE, WE TESTED THE HYPOTHESIS THAT CHRONIC HYPOXIA LEADS TO THE UPREGULATION OF A CORE GROUP OF GENES WITH ASSOCIATED CHANGES IN THE PROMOTER DNA METHYLATION THAT MEDIATES THE CELL SURVIVAL UNDER HYPOXIA. RESULTS : WE EXAMINED THE EFFECT OF CHRONIC HYPOXIA (3 DAYS; 0.5% OXYGEN) ON HUMAN BRAIN MICRO ENDOTHELIAL CELLS (HBMEC) VIABILITY AND APOPTOSIS. HYPOXIA CAUSED A SIGNIFICANT REDUCTION IN CELL VIABILITY AND AN INCREASE IN APOPTOSIS. NEXT, WE EXAMINED CHRONIC HYPOXIA ASSOCIATED CHANGES IN TRANSCRIPTOME AND GENOME-WIDE PROMOTER METHYLATION. THE DATA OBTAINED WAS COMPARED WITH 16 OTHER MICROARRAY STUDIES ON CHRONIC HYPOXIA. NINE GENES WERE ALTERED IN RESPONSE TO CHRONIC HYPOXIA IN ALL 17 STUDIES. INTERESTINGLY, HIF1A WAS NOT ALTERED WITH CHRONIC HYPOXIA IN ANY OF THE STUDIES. FURTHERMORE, WE COMPARED OUR DATA TO THREE OTHER STUDIES THAT IDENTIFIED HIF-RESPONSIVE GENES BY VARIOUS APPROACHES. ONLY TWO GENES WERE FOUND TO BE HIF DEPENDENT. WE SILENCED EACH OF THESE 9 GENES USING CRISPR/CAS9 SYSTEM. DOWNREGULATION OF EGLN3 SIGNIFICANTLY INCREASED THE CELL DEATH UNDER CHRONIC HYPOXIA, WHEREAS DOWNREGULATION OF ERO1L, ENO2, ADRENOMEDULLIN, AND SPAG4 REDUCED THE CELL DEATH UNDER HYPOXIA. CONCLUSIONS : WE PROVIDE A CORE GROUP OF GENES THAT REGULATES CELLULAR ACCLIMATIZATION UNDER CHRONIC HYPOXIC STRESS, AND MOST OF THEM ARE HIF INDEPENDENT. 2017 10 164 29 ABNORMAL HISTONE METHYLATION IS RESPONSIBLE FOR INCREASED VASCULAR ENDOTHELIAL GROWTH FACTOR 165A SECRETION FROM AIRWAY SMOOTH MUSCLE CELLS IN ASTHMA. VASCULAR ENDOTHELIAL GROWTH FACTOR (VEGF), A KEY ANGIOGENIC MOLECULE, IS ABERRANTLY EXPRESSED IN SEVERAL DISEASES INCLUDING ASTHMA WHERE IT CONTRIBUTES TO BRONCHIAL VASCULAR REMODELING AND CHRONIC INFLAMMATION. ASTHMATIC HUMAN AIRWAY SMOOTH MUSCLE CELLS HYPERSECRETE VEGF, BUT THE MECHANISM IS UNCLEAR. IN THIS STUDY, WE DEFINED THE MECHANISM IN HUMAN AIRWAY SMOOTH MUSCLE CELLS FROM NONASTHMATIC AND ASTHMATIC PATIENTS. WE FOUND THAT ASTHMATIC CELLS LACKED A REPRESSION COMPLEX AT THE VEGF PROMOTER, WHICH WAS PRESENT IN NONASTHMATIC CELLS. RECRUITMENT OF G9A, TRIMETHYLATION OF HISTONE H3 AT LYSINE 9 (H3K9ME3), AND A RESULTANT DECREASE IN RNA POLYMERASE II AT THE VEGF PROMOTER WAS CRITICAL TO REPRESSION OF VEGF SECRETION IN NONASTHMATIC CELLS. AT THE ASTHMATIC PROMOTER, H3K9ME3 WAS ABSENT BECAUSE OF FAILED RECRUITMENT OF G9A; RNA POLYMERASE II BINDING, IN ASSOCIATION WITH TATA-BINDING PROTEIN-ASSOCIATED FACTOR 1, WAS INCREASED; H3K4ME3 WAS PRESENT; AND SP1 BINDING WAS EXAGGERATED AND SUSTAINED. IN CONTRAST, DNA METHYLATION AND HISTONE ACETYLATION WERE SIMILAR IN ASTHMATIC AND NONASTHMATIC CELLS. THIS IS THE FIRST STUDY, TO OUR KNOWLEDGE, TO SHOW THAT AIRWAY CELLS IN ASTHMA HAVE ALTERED EPIGENETIC REGULATION OF REMODELING GENE(S). HISTONE METHYLATION AT GENES SUCH AS VEGF MAY BE AN IMPORTANT NEW THERAPEUTIC TARGET. 2012 11 1011 27 CIGARETTE SMOKE CONDENSATE INDUCES DIFFERENTIAL EXPRESSION AND PROMOTER METHYLATION PROFILES OF CRITICAL GENES INVOLVED IN LUNG CANCER IN NL-20 LUNG CELLS IN VITRO: SHORT-TERM AND CHRONIC EXPOSURE. ESTABLISHING EARLY DIAGNOSTIC MARKERS OF HARM IS CRITICAL FOR EFFECTIVE PREVENTION PROGRAMS AND REGULATION OF TOBACCO PRODUCTS. THIS STUDY EXAMINED EFFECTS OF CIGARETTE SMOKE CONDENSATE (CSC) ON EXPRESSION AND PROMOTER METHYLATION PROFILE OF CRITICAL GENES (DAPK, ECAD, MGMT, AND RASSF1A) INVOLVED IN LUNG CANCER DEVELOPMENT IN DIFFERENT HUMAN LUNG CELL LINES. NL-20 CELLS WERE TREATED WITH 0.1-100 MUG/ML OF CSC FOR 24 TO 72 HRS FOR SHORT-TERM EXPOSURES. DAPK EXPRESSION OR METHYLATION STATUS WAS NOT SIGNIFICANTLY AFFECTED. HOWEVER, CSC TREATMENT RESULTED IN CHANGES IN EXPRESSION AND PROMOTER METHYLATION PROFILE OF ECAD, MGMT, AND RASSF1A. FOR CHRONIC STUDIES, CELLS WERE EXPOSED TO 1 OR 10 MUG/ML CSC UP TO 28 DAYS. CELLS SHOWED MORPHOLOGICAL CHANGES ASSOCIATED WITH TRANSFORMATION AND CHANGES IN INVASION CAPACITIES AND GLOBAL METHYLATION STATUS. THIS STUDY PROVIDES CRITICAL DATA SUGGESTING THAT EPIGENETIC CHANGES COULD SERVE AS AN EARLY BIOMARKER OF HARM DUE TO EXPOSURE TO CIGARETTE SMOKE. 2013 12 2297 30 EPIGENETIC REGULATION OF ACUTE INFLAMMATORY PAIN. ACUTE PAIN IS ASSOCIATED WITH TISSUE DAMAGE, WHICH RESULTS IN THE RELEASE OF INFLAMMATORY MEDIATORS. RECENT STUDIES POINT TO THE INVOLVEMENT OF EPIGENETIC MECHANISMS (DNA METHYLATION) IN THE DEVELOPMENT OF PAIN. WE HAVE FOUND THAT DURING ACUTE INFLAMMATORY PAIN INDUCED BY THE APPLICATION OF 10% MUSTARD OIL ON THE TONGUES OF RATS, LEVELS OF DNMT3A AND 3B WERE ELEVATED MARKEDLY (36 AND 42 % RESPECTIVELY), WHEREAS THE LEVEL OF DNMT1 WAS NOT CHANGED SIGNIFICANTLY. PREVIOUS INJECTION OF XEFOCAM WITH 0,4 MG/KG DOSE DECREASED LEVELS OF DNMT3A AND 3B (25 AND 24% RESPECTIVELY). THE LEVEL OF DNMT1 WAS NOT CHANGED SIGNIFICANTLY COMPARED TO THE CONTROL GROUP. THE FINDINGS SUPPORT THE IDEA THAT INHIBITORS OF DNA-METHYLTRANSFERASES COULD BE USEFUL FOR PAIN MANAGEMENT. OUR DATA SUGGEST THAT NSAIDS (ALONE OR IN COMBINATION WITH DNMT INHIBITORS) MAY BE PROPOSED AS POSSIBLE EPIGENETIC REGULATORY AGENTS, WHICH MAY PLAY A ROLE IN EPIGENETIC MECHANISMS INDIRECTLY THROUGH ALTERING THE ACTIVITY OF INFLAMMATORY MEDIATORS INVOLVED IN PAIN DEVELOPMENT. 2014 13 1545 31 DNA METHYLATION IN LIVER TUMORIGENESIS IN FISH FROM THE ENVIRONMENT. THE LINK BETWEEN ENVIRONMENT, ALTERATION IN DNA METHYLATION AND CANCER HAS BEEN WELL ESTABLISHED IN HUMANS; YET, IT IS UNDER-STUDIED IN UNSEQUENCED NON-MODEL ORGANISMS. THE OCCURRENCE OF LIVER TUMORS IN THE FLATFISH DAB COLLECTED AT CERTAIN UK SAMPLING SITES EXCEEDS 20%, YET THE CAUSATIVE AGENTS AND THE MOLECULAR MECHANISMS OF TUMOR FORMATION ARE NOT KNOWN, ESPECIALLY REGARDING THE BALANCE BETWEEN EPIGENETIC AND GENETIC FACTORS. METHYLATED DNA IMMUNOPRECIPITATION (MEDIP) COMBINED WITH DE NOVO HIGH-THROUGHPUT DNA SEQUENCING WERE USED TO INVESTIGATE DNA METHYLATION CHANGES IN DAB HEPATOCELLULAR ADENOMA TUMORS FOR THE FIRST TIME IN AN UNSEQUENCED SPECIES. NOVEL CUSTOM-MADE DAB GENE EXPRESSION ARRAYS WERE DESIGNED AND USED TO DETERMINE THE RELATIONSHIP BETWEEN DNA METHYLATION AND GENE EXPRESSION. IN ADDITION, THE CONFIRMATORY TECHNIQUES OF BISULFITE SEQUENCING PCR (BSP) AND RT-PCR WERE APPLIED. GENES INVOLVED IN PATHWAYS RELATED TO CANCER, INCLUDING APOPTOSIS, WNT/BETA-CATENIN SIGNALING AND GENOMIC AND NON-GENOMIC ESTROGEN RESPONSES, WERE ALTERED BOTH IN METHYLATION AND TRANSCRIPTION. GLOBAL METHYLATION WAS STATISTICALLY SIGNIFICANTLY 1.8-FOLD REDUCED IN HEPATOCELLULAR ADENOMA AND NON-CANCEROUS SURROUNDING TISSUES COMPARED WITH LIVER FROM NON-CANCER BEARING DAB. BASED ON THE IDENTIFIED CHANGES AND CHEMICAL EXPOSURE DATA, OUR STUDY SUPPORTS THE EPIGENETIC MODEL OF CANCER. WE HYPOTHESIZE THAT CHRONIC EXPOSURE TO A MIXTURE OF ENVIRONMENTAL CONTAMINANTS CONTRIBUTES TO A GLOBAL HYPOMETHYLATION FOLLOWED BY FURTHER EPIGENETIC AND GENOMIC CHANGES. THE FINDINGS SUGGEST A LINK BETWEEN ENVIRONMENT, EPIGENETICS AND CANCER IN FISH TUMORS IN THE WILD AND SHOW THE UTILITY OF THIS METHODOLOGY FOR STUDIES IN NON-MODEL ORGANISMS. 2011 14 1567 35 DNA METHYLATION OF THE KLF14 GENE REGION IN WHOLE BLOOD CELLS PROVIDES PREDICTION FOR THE CHRONIC INFLAMMATION IN THE ADIPOSE TISSUE. KRUPPEL-LIKE FACTOR 14 (KLF14) GENE, WHICH APPEARS TO BE A MASTER REGULATOR OF GENE EXPRESSION IN THE ADIPOSE TISSUE AND HAVE PREVIOUSLY BEEN ASSOCIATED WITH BMI AND TYPE 2 DIABETES (T2D) BY LARGE GENOME-WIDE ASSOCIATION STUDIES. IN ORDER TO FIND PREDICTIVE BIOMARKERS FOR THE DEVELOPMENT OF T2D, IT IS NECESSARY TO TAKE EPIGENOMIC CHANGES AFFECTED BY ENVIRONMENTAL FACTORS INTO ACCOUNT. THIS STUDY FOCUSES ON AGEING AND OBESITY, WHICH ARE T2D RISK FACTORS, AND EXAMINES EPIGENETIC CHANGES AND INFLAMMATORY CHANGES. WE INVESTIGATED DNA METHYLATION CHANGES IN THE KLF14 PROMOTER REGION IN DIFFERENT ORGANS OF MICE FOR COMPARING AGING AND WEIGHT. WE FOUND THAT METHYLATION LEVELS OF THESE SITES WERE INCREASED WITH AGING AND WEIGHT IN THE SPLEEN, THE ADIPOSE TISSUE, THE KIDNEY, THE LUNG, THE COLON AND THE WHOLE BLOOD CELLS. IN ADDITION, IN THE SPLEEN, THE ADIPOSE TISSUE AND THE WHOLE BLOOD, THESE EPIGENETIC CHANGES WERE ALSO SIGNIFICANTLY ASSOCIATED WITH INFLAMMATORY LEVELS. MOREOVER, NOT ONLY KLF14, BUT ALSO EXPRESSION LEVELS OF SOME DOWNSTREAM GENES WERE DECREASED WITH METHYLATION IN THE SPLEEN, THE ADIPOSE TISSUE AND THE WHOLE BLOOD CELLS. TAKEN TOGETHER, OUR RESULTS SUGGEST THAT METHYLATION CHANGES OF KLF14 IN THOSE TISSUES MAY BE ASSOCIATED WITH CHANGES IN GENE EXPRESSION AND INFLAMMATION ON THE ADIPOSE TISSUE OF OBESITY AND T2D. IN ADDITION, THE METHYLATION CHANGES IN THE WHOLE BLOOD CELLS MAY SERVE AS A PREDICTIVE EPIGENETIC BIOMARKER FOR THE DEVELOPMENT OF T2D. 2018 15 1739 29 EARLY DNA METHYLATION CHANGES IN CHILDREN DEVELOPING BETA CELL AUTOIMMUNITY AT A YOUNG AGE. AIMS/HYPOTHESIS: TYPE 1 DIABETES IS A CHRONIC AUTOIMMUNE DISEASE OF COMPLEX AETIOLOGY, INCLUDING A POTENTIAL ROLE FOR EPIGENETIC REGULATION. PREVIOUS EPIGENOMIC STUDIES FOCUSED MAINLY ON CLINICALLY DIAGNOSED INDIVIDUALS. THE AIM OF THE STUDY WAS TO ASSESS EARLY DNA METHYLATION CHANGES ASSOCIATED WITH TYPE 1 DIABETES ALREADY BEFORE THE DIAGNOSIS OR EVEN BEFORE THE APPEARANCE OF AUTOANTIBODIES. METHODS: REDUCED REPRESENTATION BISULPHITE SEQUENCING (RRBS) WAS APPLIED TO STUDY DNA METHYLATION IN PURIFIED CD4(+) T CELL, CD8(+) T CELL AND CD4(-)CD8(-) CELL FRACTIONS OF 226 PERIPHERAL BLOOD MONONUCLEAR CELL SAMPLES LONGITUDINALLY COLLECTED FROM SEVEN TYPE 1 DIABETES-SPECIFIC AUTOANTIBODY-POSITIVE INDIVIDUALS AND CONTROL INDIVIDUALS MATCHED FOR AGE, SEX, HLA RISK AND PLACE OF BIRTH. WE ALSO EXPLORED CORRELATIONS BETWEEN DNA METHYLATION AND GENE EXPRESSION USING RNA SEQUENCING DATA FROM THE SAME SAMPLES. TECHNICAL VALIDATION OF RRBS RESULTS WAS PERFORMED USING PYROSEQUENCING. RESULTS: WE IDENTIFIED 79, 56 AND 45 DIFFERENTIALLY METHYLATED REGIONS IN CD4(+) T CELLS, CD8(+) T CELLS AND CD4(-)CD8(-) CELL FRACTIONS, RESPECTIVELY, BETWEEN TYPE 1 DIABETES-SPECIFIC AUTOANTIBODY-POSITIVE INDIVIDUALS AND CONTROL PARTICIPANTS. THE ANALYSIS OF PRE-SEROCONVERSION SAMPLES IDENTIFIED DNA METHYLATION SIGNATURES AT THE VERY EARLY STAGE OF DISEASE, INCLUDING DIFFERENTIAL METHYLATION AT THE PROMOTER OF IRF5 IN CD4(+) T CELLS. FURTHER, WE VALIDATED RRBS RESULTS USING PYROSEQUENCING AT THE FOLLOWING CPG SITES: CHR19:18118304 IN THE PROMOTER OF ARRDC2; CHR21:47307815 IN THE INTRON OF PCBP3; AND CHR14:81128398 IN THE INTERGENIC REGION NEAR TRAF3 IN CD4(+) T CELLS. CONCLUSIONS/INTERPRETATION: THESE PRELIMINARY RESULTS PROVIDE NOVEL INSIGHTS INTO CELL TYPE-SPECIFIC DIFFERENTIAL EPIGENETIC REGULATION OF GENES, WHICH MAY CONTRIBUTE TO TYPE 1 DIABETES PATHOGENESIS AT THE VERY EARLY STAGE OF DISEASE DEVELOPMENT. SHOULD THESE FINDINGS BE VALIDATED, THEY MAY SERVE AS A POTENTIAL SIGNATURE USEFUL FOR DISEASE PREDICTION AND MANAGEMENT. 2022 16 5972 24 TET REPRESSION AND INCREASED DNMT ACTIVITY SYNERGISTICALLY INDUCE ABERRANT DNA METHYLATION. CHRONIC INFLAMMATION IS DEEPLY INVOLVED IN VARIOUS HUMAN DISORDERS, SUCH AS CANCER, NEURODEGENERATIVE DISORDERS, AND METABOLIC DISORDERS. INDUCTION OF EPIGENETIC ALTERATIONS, ESPECIALLY ABERRANT DNA METHYLATION, IS ONE OF THE MAJOR MECHANISMS, BUT HOW IT IS INDUCED IS STILL UNCLEAR. HERE, WE FOUND THAT EXPRESSION OF TET GENES, METHYLATION ERASERS, WAS DOWNREGULATED IN INFLAMED MOUSE AND HUMAN TISSUES, AND THAT THIS WAS CAUSED BY UPREGULATION OF TET-TARGETING MIRNAS SUCH AS MIR20A, MIR26B, AND MIR29C, LIKELY DUE TO ACTIVATION OF NF-KAPPAB SIGNALING DOWNSTREAM OF IL-1BETA AND TNF-ALPHA. HOWEVER, TET KNOCKDOWN INDUCED ONLY MILD ABERRANT METHYLATION. NITRIC OXIDE (NO), PRODUCED BY NOS2, ENHANCED ENZYMATIC ACTIVITY OF DNA METHYLTRANSFERASES (DNMTS), METHYLATION WRITERS, AND NO EXPOSURE INDUCED MINIMAL ABERRANT METHYLATION. IN CONTRAST, A COMBINATION OF TET KNOCKDOWN AND NO EXPOSURE SYNERGISTICALLY INDUCED ABERRANT METHYLATION, INVOLVING GENOMIC REGIONS NOT METHYLATED BY EITHER ALONE. THE RESULTS SHOWED THAT A VICIOUS COMBINATION OF TET REPRESSION, DUE TO NF-KAPPAB ACTIVATION, AND DNMT ACTIVATION, DUE TO NO PRODUCTION, IS RESPONSIBLE FOR ABERRANT METHYLATION INDUCTION IN HUMAN TISSUES. 2020 17 217 32 ACUTE EXERCISE INCREASES THE EXPRESSION OF KIR2DS4 BY PROMOTER DEMETHYLATION IN NK CELLS. POSITIVE EFFECTS OF EXERCISE ON CANCER PREVENTION AND PROGRESSION HAVE BEEN PROPOSED TO BE MEDIATED BY STIMULATING NATURAL KILLER (NK) CELLS. BECAUSE NK CELL RECEPTORS ARE REGULATED BY EPIGENETIC MODIFICATIONS, WE INVESTIGATED WHETHER ACUTE AEROBIC EXERCISE AND TRAINING CHANGE PROMOTER DNA METHYLATION AND GENE EXPRESSION OF THE ACTIVATING KIR2DS4 AND THE INHIBITING KIR3DL1 GENE. SIXTEEN HEALTHY WOMEN (50-60 YEARS) PERFORMED A GRADED EXERCISE TEST (GXT) AND WERE RANDOMIZED INTO EITHER A PASSIVE CONTROL GROUP OR AN INTERVENTION GROUP PERFORMING A FOUR-WEEK ENDURANCE EXERCISE INTERVENTION. BLOOD SAMPLES (PRE-, POST-GXT AND POST-TRAINING) WERE USED FOR ISOLATION OF DNA/RNA OF NK CELLS TO ASSESS DNA PROMOTER METHYLATION BY TARGETED DEEP-AMPLICON SEQUENCING AND GENE EXPRESSION BY QRT-PCR. POTENTIAL CHANGES IN NK CELL SUBSETS WERE DETERMINED BY FLOW CYTOMETRY. ACUTE AND CHRONIC EXERCISE DID NOT PROVOKE SIGNIFICANT ALTERATIONS OF NK CELL PROPORTIONS. PROMOTER METHYLATION DECREASED AND GENE EXPRESSION INCREASED FOR KIR2DS4 AFTER ACUTE EXERCISE. A HIGH GENE EXPRESSION CORRELATED WITH A LOW METHYLATION OF CPGS THAT WERE ALTERED BY ACUTE EXERCISE. CHRONIC EXERCISE RESULTED IN A MINOR DECREASE OF DNA METHYLATION AND DID NOT ALTER GENE EXPRESSION. ACUTE EXERCISE PROVOKES EPIGENETIC MODIFICATIONS, AFFECTING THE BALANCE BETWEEN THE ACTIVATING KIR2DS4 AND THE INHIBITING KIR3DL1, WITH POTENTIAL BENEFITS ON NK CELL FUNCTION. 2019 18 194 33 ACETYLSHIKONIN SUPPRESSES INVASION OF PORPHYROMONAS GINGIVALIS?INFECTED YD10B ORAL CANCER CELLS BY MODULATING THE INTERLEUKIN-8/MATRIX METALLOPROTEINASE AXIS. THE DEVELOPMENT OF PHARMACEUTICAL AGENTS POSSESSING ANTI?INVASIVE AND ANTI?METASTATIC ABILITIES, AS WELL AS APOPTOTIC ACTIVITY, IS IMPORTANT IN DECREASING THE INCIDENCE AND RECURRENCE OF ORAL CANCER. CANCER CELLS ARE KNOWN TO ACQUIRE INVASIVENESS NOT ONLY THROUGH EPIGENETIC CHANGES, BUT ALSO FROM INFLAMMATORY STIMULI WITHIN THE TUMOR MICROENVIRONMENT. ACCORDINGLY, THE IDENTIFICATION OF AGENTS THAT CAN SUPPRESS THE INFLAMMATION?PROMOTED INVASIVENESS OF CANCER CELLS MAY BE IMPORTANT IN TREATING CANCER AND IMPROVING THE PROGNOSIS OF PATIENTS WITH CANCER. ACETYLSHIKONIN, A FLAVONOID WITH ANTI?INFLAMMATORY ACTIVITY, INHIBITS PROLIFERATION AND INDUCES APOPTOSIS OF ORAL CANCER CELLS. IN THE PRESENT STUDY, THE ANTI?INVASIVE EFFECT OF ACETYLSHIKONIN ON YD10B ORAL CANCER CELLS INFECTED WITH PORPHYROMONAS GINGIVALIS, A MAJOR PATHOGEN OF CHRONIC PERIODONTITIS, AND THE MECHANISMS INVOLVED WERE INVESTIGATED. FIRSTLY, WE EXAMINED WHETHER P. GINGIVALIS INFECTION INCREASED THE INVASIVENESS OF YD10B CELLS. RESULTS SUGGESTED THAT YD10B ORAL CANCER CELLS BECOME MORE AGGRESSIVE WHEN THEY ARE INFECTED WITH P. GINGIVALIS. SECONDLY, ACETYLSHIKONIN SIGNIFICANTLY INHIBITED THE INVASION OF P. GINGIVALIS?INFECTED YD10B CELLS BY SUPPRESSING IL?8 RELEASE AND IL?8?DEPENDENT MMP RELEASE. THESE DATA SUGGEST THAT ACETYLSHIKONIN MAY BE A USEFUL PREVENTIVE AND THERAPEUTIC CANDIDATE FOR ORAL CANCER THAT IS CHRONICALLY INFECTED WITH PERIODONTAL PATHOGENS. 2018 19 1965 31 EPIGENETIC ALTERATION OF MITOCHONDRIAL BIOGENESIS REGULATORY GENES IN ARSENIC EXPOSED INDIVIDUALS (WITH AND WITHOUT SKIN LESIONS) AND IN SKIN CANCER TISSUES: A CASE CONTROL STUDY. CHRONIC ARSENIC TOXICITY HAS BECOME A GLOBAL CONCERN DUE TO ITS ADVERSE PATHOPHYSIOLOGICAL OUTCOME AND CARCINOGENIC POTENTIAL. IT IS ALREADY ESTABLISHED THAT ARSENIC INDUCED REACTIVE OXYGEN SPECIES ALTERS MITOCHONDRIAL FUNCTIONALITY. MAJOR REGULATORY GENES FOR MITOCHONDRIAL BIOGENESIS, I.E., PGC1ALPHA, TFAM, NRF1AND NRF2 ARE LOCATED IN THE NUCLEUS. AS A RESULT, MITOCHONDRIA-NUCLEUS CROSSTALK IS CRUCIAL FOR PROPER MITOCHONDRIAL FUNCTION. THIS PREVIOUS HYPOTHESIS LED US TO INVESTIGATEINVOLVEMENT OF EPIGENETIC ALTERATION BEHINDENHANCED MITOCHONDRIAL BIOGENESIS IN CHRONIC ARSENIC EXPOSURE. AN EXTENSIVE CASE-CONTROL STUDY WAS CONDUCTED WITH 390 STUDY PARTICIPANTS (UNEXPOSED, EXPOSED WITHOUT SKIN LESION, EXPOSED WITH SKIN LESION AND EXPOSED SKIN TUMOUR) FROM HIGHLY ARSENIC EXPOSED AREAS OFWEST BENGAL, INDIA. METHYLATION SPECIFIC PCRREVEALED SIGNIFICANT PROMOTER HYPOMETHYLATION OFTWO KEY BIOGENESIS REGULATORY GENES, PGC1ALPHAANDTFAM IN ARSENIC EXPOSED INDIVIDUALS AND ALSO IN SKIN TUMOUR TISSUES. LINEAR REGRESSION ANALYSIS INDICATED SIGNIFICANT NEGATIVE CORRELATION BETWEEN URINARY ARSENIC CONCENTRATION AND PROMOTER METHYLATION STATUS. INCREASED EXPRESSION OF BIOGENESIS REGULATORY GENES WASOBTAINED BY QUANTITATIVE REAL-TIME PCR ANALYSIS. MOREOVER, ALTERED MITOCHONDRIAL FUSION-FISSION REGULATORY GENE EXPRESSION WAS ALSO OBSERVED IN SKIN TUMOUR TISSUES. MIR663, HAVING TUMOUR SUPPRESSOR GENE LIKE FUNCTION WAS KNOWN TO BE EPIGENETICALLY REGULATED THROUGH MITOCHONDRIAL RETROGRADE SIGNAL. PROMOTER HYPERMETHYLATION WITH SIGNIFICANTLY DECREASED EXPRESSION OF MIR663 WAS FOUND IN SKIN CANCER TISSUES COMPARED TO NON-CANCEROUS CONTROL TISSUE. IN CONCLUSION, RESULTS INDICATED CRUCIAL ROLE OF EPIGENETIC ALTERATION IN ARSENIC INDUCED MITOCHONDRIAL BIOGENESIS AND ARSENICAL SKIN CARCINOGENESIS FOR THE FIRST TIME. HOWEVER, FURTHER MECHANISTIC STUDIES ARE NECESSARY FOR DETAILED UNDERSTANDING OF MITOCHONDRIA-NUCLEUS CROSSTALK IN ARSENIC PERTURBATION. 2020 20 3658 34 INDUCTION OF ABERRANT TRIMETHYLATION OF HISTONE H3 LYSINE 27 BY INFLAMMATION IN MOUSE COLONIC EPITHELIAL CELLS. A FIELD FOR CANCERIZATION (FIELD DEFECT), WHERE GENETIC AND EPIGENETIC ALTERATIONS ARE ACCUMULATED IN NORMAL-APPEARING TISSUES, IS INVOLVED IN HUMAN CARCINOGENESIS, ESPECIALLY CANCERS ASSOCIATED WITH CHRONIC INFLAMMATION. ALTHOUGH ABERRANT DNA METHYLATION IS INVOLVED IN THE FIELD DEFECT AND INDUCED BY CHRONIC INFLAMMATION, IT IS STILL UNCLEAR FOR TRIMETHYLATION OF HISTONE H3 LYSINE 27 (H3K27ME3), WHICH IS INVOLVED IN GENE REPRESSION INDEPENDENT OF DNA METHYLATION AND FUNCTIONS AS A PRE-MARK FOR ABERRANT DNA METHYLATION. IN THIS STUDY, USING A MOUSE COLITIS MODEL INDUCED BY DEXTRAN SULFATE SODIUM (DSS), WE AIMED TO CLARIFY WHETHER ABERRANT H3K27ME3 IS INDUCED BY INFLAMMATION AND INVOLVED IN A FIELD DEFECT. CHIP-ON-CHIP ANALYSIS OF COLONIC EPITHELIAL CELLS REVEALED THAT H3K27ME3 LEVELS WERE INCREASED OR DECREASED FOR 266 GENOMIC REGIONS BY AGING, AND MORE EXTENSIVELY (23 INCREASED AND 3574 DECREASED REGIONS) BY COLITIS. SUCH INCREASE OR DECREASE OF H3K27ME3 WAS INDUCED AS EARLY AS 2 WEEKS AFTER THE INITIATION OF DSS TREATMENT, AND PERSISTED AT LEAST FOR 16 WEEKS EVEN AFTER THE INFLAMMATION DISAPPEARED. SOME OF THE ABERRANT H3K27ME3 IN COLONIC EPITHELIAL CELLS WAS CARRIED OVER INTO COLON TUMORS. FURTHERMORE, H3K27ME3 ACQUIRED AT DAPK1 BY COLITIS WAS FOLLOWED BY INCREASED DNA METHYLATION, SUPPORTING ITS FUNCTION AS A PRE-MARK FOR ABERRANT DNA METHYLATION. THESE RESULTS DEMONSTRATED THAT ABERRANT H3K27ME3 CAN BE INDUCED BY EXPOSURE TO A SPECIFIC ENVIRONMENT, SUCH AS COLITIS, AND SUGGESTED THAT ABERRANT HISTONE MODIFICATION, IN ADDITION TO ABERRANT DNA METHYLATION, IS INVOLVED IN THE FORMATION OF A FIELD DEFECT. 2012