1 1615 124 DNA METHYLTRANSFERASE 3B PLAYS A PROTECTIVE ROLE AGAINST HEPATOCARCINOGENESIS CAUSED BY CHRONIC INFLAMMATION VIA MAINTAINING MITOCHONDRIAL HOMEOSTASIS. MOST HEPATOCELLULAR CARCINOMAS (HCCS) DEVELOP ON THE BASIS OF CHRONIC HEPATITIS, BUT THE MECHANISM OF EPIGENETIC REGULATION IN INFLAMMATORY HEPATOCARCINOGENESIS HAS YET TO BE ELUCIDATED. AMONG DE NOVO DNA METHYLTRANSFERASES (DNMTS), DNMT3B HAS LATELY BEEN REPORTED TO ACT SPECIFICALLY ON ACTIVELY TRANSCRIBED GENES, SUGGESTING THE POSSIBILITY THAT IT PLAYS A ROLE IN THE PATHOGENESIS OF CANCER. WE CONFIRMED THAT DNMT3B ISOFORMS LACKING ITS CATALYTIC DOMAIN WERE HIGHLY EXPRESSED IN HCCS COMPARED WITH NON-TUMOROUS LIVER TISSUE. TO ELUCIDATE THE ROLE OF DNMT3B IN HEPATOCARCINOGENESIS, WE GENERATED A GENETICALLY ENGINEERED MOUSE MODEL WITH HEPATOCYTE-SPECIFIC DNMT3B DELETION. THE LIVER OF THE DNMT3B-DEFICIENT MICE EXHIBITED AN EXACERBATION OF THIOACETAMIDE-INDUCED HEPATITIS, PROGRESSION OF LIVER FIBROSIS AND A HIGHER INCIDENCE OF HCC COMPARED WITH THE LIVER OF THE CONTROL MICE. WHOLE-GENOME BISULFITE SEQUENCING VERIFIED A LOWER CG METHYLATION LEVEL IN THE DNMT3B-DEFICIENT LIVER, DEMONSTRATING DIFFERENTIALLY METHYLATED REGIONS THROUGHOUT THE GENOME. TRANSCRIPTOME ANALYSIS REVEALED DECREASED EXPRESSION OF GENES RELATED TO OXIDATIVE PHOSPHORYLATION IN THE DNMT3B-DEFICIENT LIVER. MOREOVER, PRIMARY HEPATOCYTES ISOLATED FROM THE DNMT3B-DEFICIENT MICE SHOWED REDUCED MITOCHONDRIAL RESPIRATORY CAPACITY, LEADING TO THE ENHANCEMENT OF OXIDATIVE STRESS IN THE LIVER TISSUE. OUR FINDINGS SUGGEST THE PROTECTIVE ROLE OF DNMT3B AGAINST CHRONIC INFLAMMATION AND HCC DEVELOPMENT VIA MAINTAINING MITOCHONDRIAL HOMEOSTASIS. 2020 2 5972 27 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 3 3527 26 IL-6 ENHANCES THE NUCLEAR TRANSLOCATION OF DNA CYTOSINE-5-METHYLTRANSFERASE 1 (DNMT1) VIA PHOSPHORYLATION OF THE NUCLEAR LOCALIZATION SEQUENCE BY THE AKT KINASE. THE EPIGENETIC PROGRAMMING OF GENOMIC DNA IS ACCOMPLISHED, IN PART, BY SEVERAL DNA CYTOSINE-5-METHYLTRANSFERASES THAT ACT BY COVALENTLY MODIFYING CYTOSINES WITH THE ADDITION OF A METHYL GROUP. THIS COVALENT MODIFICATION IS MAINTAINED BY THE DNA CYTOSINE-5-METHYLTRANSFERASE-1 ENZYME (DNMT1), WHICH IS CAPABLE OF ACTING IN CONCERT WITH OTHER SIMILAR ENZYMES TO SILENCE IMPORTANT TUMOR SUPPRESSOR GENES. IL-6 IS A MULTIFUNCTIONAL MEDIATOR OF INFLAMMATION, ACTING THROUGH SEVERAL MAJOR SIGNALING CASCADES, INCLUDING THE PHOSPHATIDYLINOSITOL-3-KINASE PATHWAY (PI-3-K), WHICH ACTIVATES PROTEIN KINASE B (AKT/PKB) DOWNSTREAM. HERE, WE SHOW THAT THE SUBCELLULAR LOCALIZATION OF DNMT1 CAN BE ALTERED BY THE ADDITION OF IL-6, INCREASING THE RATE OF NUCLEAR TRANSLOCATION OF THE ENZYME FROM THE CYTOSOLIC COMPARTMENT. THE MECHANISM OF NUCLEAR TRANSLOCATION OF DNMT1 IS GREATLY ENHANCED BY PHOSPHORYLATION OF THE DNMT1 NUCLEAR LOCALIZATION SIGNAL (NLS) BY PKB/AKT KINASE. MUTAGENIC ALTERATION OF THE TWO AKT TARGET AMINO ACIDS WITHIN THE NLS RESULTS IN A MAJOR LOSS OF DNMT1 NUCLEAR TRANSLOCATION, WHILE THE CREATION OF A "PHOSPHO-MIMIC" AMINO ACID (MUTATION TO ACIDIC RESIDUES) RESTORES THIS COMPARTMENTATION ABILITY. THESE OBSERVATIONS SUGGEST AN INTERESTING HYPOTHESIS REGARDING HOW MEDIATORS OF CHRONIC INFLAMMATION MAY DISTURB THE DELICATE BALANCE OF CELLULAR COMPARTMENTALIZATION OF IMPORTANT PROTEINS, AND REVEALS A POTENTIAL MECHANISM FOR THE INDUCTION OR ENHANCEMENT OF TUMOR GROWTH VIA ALTERATION OF THE COMPONENTS INVOLVED IN THE EPIGENETIC PROGRAMMING OF A CELL. 2007 4 6092 31 THE EFFECTS OF EPIGENETIC MODIFICATION ON THE OCCURRENCE AND PROGRESSION OF LIVER DISEASES AND THE INVOLVED MECHANISM. INTRODUCTION: EPIGENETIC MODIFICATION IS A TYPE OF GENE EXPRESSION AND REGULATION THAT DOES NOT INVOLVE CHANGES IN DNA SEQUENCES. AN INCREASING NUMBER OF STUDIES HAVE PROVEN THAT EPIGENETIC MODIFICATIONS PLAY AN IMPORTANT ROLE IN THE OCCURRENCE AND PROGRESSION OF LIVER DISEASES THROUGH THE GENE REGULATION AND PROTEIN EXPRESSIONS OF HEPATOCELLULAR LIPID METABOLISM, INFLAMMATORY REACTION, CELL PROLIFERATION, AND ACTIVATION, ETC.AREAS COVERED: IN THIS STUDY, WE ELABORATED AND ANALYZED THE UNDERLYING FUNCTIONAL MECHANISM OF EPIGENETIC MODIFICATION IN ALCOHOLIC LIVER DISEASE (ALD), NONALCOHOLIC FATTY LIVER DISEASE (NAFLD), LIVER FIBROSIS (LF), VIRAL HEPATITIS, HEPATOCELLULAR CARCINOMA (HCC), AND RESEARCH PROGRESS OF RECENT YEARS.EXPERT OPINION: THE FURTHER UNDERSTANDING OF EPIGENETIC MECHANISMS THAT CAN REGULATE GENE EXPRESSION AND CELL PHENOTYPE LEADS TO NEW INSIGHTS IN EPIGENETIC CONTROL OF CHRONIC LIVER DISEASE. CURRENTLY, HEPATOLOGISTS ARE EXPLORING THE ROLE OF DNA METHYLATION, HISTONE/CHROMATIN MODIFICATION, AND NON-CODING RNA IN SPECIFIC LIVER PATHOLOGY. THESE FINDINGS HAVE LED TO ADVANCES IN DIRECT EPIGENETIC BIOMARKER TESTING OF PATIENT TISSUE OR BODY FLUID SPECIMENS, AS WELL AS QUANTITATIVE ANALYSIS. BASED ON THESE FINDINGS, DRUG VALIDATION OF SOME TARGETS INVOLVED IN THE EPIGENETIC MECHANISM OF LIVER DISEASE IS GRADUALLY BEING CARRIED OUT CLINICALLY. 2020 5 2926 27 GENERATION OF AN EPIGENETIC SIGNATURE BY CHRONIC HYPOXIA IN PROSTATE CELLS. INCREASING LEVELS OF TISSUE HYPOXIA HAVE BEEN REPORTED AS A NATURAL FEATURE OF THE AGING PROSTATE GLAND AND MAY BE A RISK FACTOR FOR THE DEVELOPMENT OF PROSTATE CANCER. IN THIS STUDY, WE HAVE USED PWR-1E BENIGN PROSTATE EPITHELIAL CELLS AND AN EQUIVALENTLY AGED HYPOXIA-ADAPTED PWR-1E SUB-LINE TO IDENTIFY PHENOTYPIC AND EPIGENETIC CONSEQUENCES OF CHRONIC HYPOXIA IN PROSTATE CELLS. WE HAVE IDENTIFIED A SIGNIFICANTLY ALTERED CELLULAR PHENOTYPE IN RESPONSE TO CHRONIC HYPOXIA AS CHARACTERIZED BY INCREASED RECEPTOR-MEDIATED APOPTOTIC RESISTANCE, THE INDUCTION OF CELLULAR SENESCENCE, INCREASED INVASION AND THE INCREASED SECRETION OF IL-1 BETA, IL6, IL8 AND TNFALPHA CYTOKINES. IN ASSOCIATION WITH THESE PHENOTYPIC CHANGES AND THE ABSENCE OF HIF-1 ALPHA PROTEIN EXPRESSION, WE HAVE DEMONSTRATED SIGNIFICANT INCREASES IN GLOBAL LEVELS OF DNA METHYLATION AND H3K9 HISTONE ACETYLATION IN THESE CELLS, CONCOMITANT WITH THE INCREASED EXPRESSION OF DNA METHYLTRANSFERASE DMNT3B AND GENE-SPECIFIC CHANGES IN DNA METHYLATION AT KEY IMPRINTING LOCI. IN CONCLUSION, WE HAVE DEMONSTRATED A GENOME-WIDE ADJUSTMENT OF DNA METHYLATION AND HISTONE ACETYLATION UNDER CHRONIC HYPOXIC CONDITIONS IN THE PROSTATE. THESE EPIGENETIC SIGNATURES MAY REPRESENT AN ADDITIONAL MECHANISM TO PROMOTE AND MAINTAIN A HYPOXIC-ADAPTED CELLULAR PHENOTYPE WITH A POTENTIAL ROLE IN TUMOUR DEVELOPMENT. 2009 6 4056 37 MAPPING THE HETEROGENEITY OF HISTONE MODIFICATIONS ON HEPATITIS B VIRUS DNA USING LIVER NEEDLE BIOPSIES OBTAINED FROM CHRONICALLY INFECTED PATIENTS. COVALENTLY CLOSED CIRCULAR DNA (CCCDNA) FORMS THE BASIS FOR REPLICATION AND PERSISTENCE OF HEPATITIS B VIRUS (HBV) IN THE CHRONICALLY INFECTED LIVER. WE HAVE PREVIOUSLY SHOWN THAT VIRAL TRANSCRIPTION IS SUBJECT TO REGULATION BY POSTTRANSLATIONAL MODIFICATIONS (PTMS) OF HISTONE PROTEINS BOUND TO CCCDNA THROUGH ANALYSIS OF DE NOVO HBV-INFECTED CELL LINES. WE NOW REPORT THE SUCCESSFUL ADAPTATION OF THIS CHROMATIN IMMUNOPRECIPITATION SEQUENCING (CHIPSEQ) APPROACH FOR ANALYSIS OF FINE-NEEDLE PATIENT LIVER BIOPSY SPECIMENS TO INVESTIGATE THE ROLE OF HISTONE PTMS IN CHRONICALLY HBV-INFECTED PATIENTS. USING 18 SPECIMENS FROM PATIENTS IN DIFFERENT STAGES OF CHRONIC HBV INFECTION, OUR WORK SHOWS THAT THE PROFILE OF HISTONE PTMS IN CHRONIC INFECTION IS MORE NUANCED THAN PREVIOUSLY OBSERVED IN IN VITRO MODELS OF ACUTE INFECTION. IN LINE WITH OUR PREVIOUS FINDINGS, WE FIND THAT THE MAJORITY OF HBV-DERIVED SEQUENCES ARE ASSOCIATED WITH THE ACTIVATING HISTONE PTM H3K4ME3. HOWEVER, WE SHOW A STRIKING INTERPATIENT VARIABILITY OF ITS DEPOSITION IN THIS PATIENT COHORT CORRELATED WITH VIRAL TRANSCRIPTION AND PATIENT HBV EARLY ANTIGEN (HBEAG) STATUS. UNEXPECTEDLY, WE DETECTED DEPOSITION OF THE CLASSICAL INHIBITORY HISTONE PTM H3K9ME3 ON HBV-DNA IN AROUND HALF OF THE PATIENT BIOPSY SPECIMENS, WHICH COULD NOT BE LINKED TO REDUCED LEVELS OF VIRAL TRANSCRIPTS. OUR RESULTS SHOW THAT CURRENT IN VITRO MODELS ARE UNABLE TO FULLY RECAPITULATE THE COMPLEX EPIGENETIC LANDSCAPE OF CHRONIC HBV INFECTION OBSERVED IN VIVO AND DEMONSTRATE THAT FINE-NEEDLE LIVER BIOPSY SPECIMENS CAN PROVIDE SUFFICIENT MATERIAL TO FURTHER INVESTIGATE THE INTERACTION OF VIRAL AND HOST PROTEINS ON HBV-DNA.IMPORTANCE HEPATITIS B VIRUS (HBV) IS A MAJOR GLOBAL HEALTH CONCERN, CHRONICALLY INFECTING MILLIONS OF PATIENTS AND CONTRIBUTING TO A RISING BURDEN OF LIVER DISEASE. THE VIRAL GENOME FORMS THE BASIS FOR CHRONIC INFECTION AND HAS BEEN SHOWN TO BE SUBJECT TO REGULATION BY EPIGENETIC MECHANISMS, SUCH AS POSTTRANSLATIONAL MODIFICATION OF HISTONE PROTEINS. HERE, WE CONFIRM AND EXPAND ON PREVIOUS RESULTS BY ADAPTING A HIGH-RESOLUTION TECHNIQUE FOR ANALYSIS OF HISTONE MODIFICATIONS FOR USE WITH PATIENT-DERIVED FINE-NEEDLE LIVER BIOPSY SPECIMENS. OUR WORK HIGHLIGHTS THAT THE SITUATION IN VIVO IS MORE COMPLEX THAN PREDICTED BY CURRENT IN VITRO MODELS, FOR EXAMPLE, BY SUGGESTING A NOVEL, NONCANONICAL ROLE OF THE HISTONE MODIFICATION H3K9ME3 IN THE HBV LIFE CYCLE. IMPORTANTLY, ENABLING THE USE OF FINE-NEEDLE LIVER BIOPSY SPECIMENS FOR SUCH HIGH-RESOLUTION ANALYSES MAY FACILITATE FURTHER RESEARCH INTO THE EPIGENETIC REGULATION OF THE HBV GENOME. 2019 7 1545 41 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 8 2025 27 EPIGENETIC CHANGES DURING DISEASE PROGRESSION IN A MURINE MODEL OF HUMAN CHRONIC LYMPHOCYTIC LEUKEMIA. EPIGENETIC ALTERATIONS, INCLUDING GAIN OR LOSS OF DNA METHYLATION, ARE A HALLMARK OF NEARLY EVERY MALIGNANCY. CHANGES IN DNA METHYLATION CAN IMPACT EXPRESSION OF CANCER-RELATED GENES INCLUDING APOPTOSIS REGULATORS AND TUMOR SUPPRESSORS. BECAUSE SUCH EPIGENETIC CHANGES ARE REVERSIBLE, THEY ARE BEING AGGRESSIVELY INVESTIGATED AS POTENTIAL THERAPEUTIC TARGETS. HERE WE USE THE EMU-TCL1 TRANSGENIC MOUSE MODEL OF CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) TO DETERMINE THE TIMING AND PATTERNS OF ABERRANT DNA METHYLATION, AND TO INVESTIGATE THE MECHANISMS THAT LEAD TO ABERRANT DNA METHYLATION. WE SHOW THAT CLL CELLS FROM EMU-TCL1 MICE AT VARIOUS STAGES RECAPITULATE EPIGENETIC ALTERATIONS SEEN IN HUMAN CLL. ABERRANT METHYLATION OF PROMOTER SEQUENCES IS OBSERVED AS EARLY AS 3 MONTHS OF AGE IN THESE ANIMALS, WELL BEFORE DISEASE ONSET. ABNORMALLY METHYLATED PROMOTER REGIONS INCLUDE BINDING SITES FOR THE TRANSCRIPTION FACTOR FOXD3. WE SHOW THAT LOSS OF FOXD3 EXPRESSION DUE TO AN NF-KAPPAB P50/P50:HDAC1 REPRESSOR COMPLEX OCCURS IN TCL1-POSITIVE B CELLS BEFORE METHYLATION. THEREFORE, SPECIFIC TRANSCRIPTIONAL REPRESSION IS AN EARLY EVENT LEADING TO EPIGENETIC SILENCING OF TARGET GENES IN MURINE AND HUMAN CLL. THESE RESULTS PROVIDE STRONG RATIONALE FOR THE DEVELOPMENT OF STRATEGIES TO TARGET NF-KAPPAB COMPONENTS IN CLL AND POTENTIALLY OTHER B-CELL MALIGNANCIES. 2009 9 2055 25 EPIGENETIC CONTROL DURING LYMPHOID DEVELOPMENT AND IMMUNE RESPONSES: ABERRANT REGULATION, VIRUSES, AND CANCER. METHYLATION OF CYTOSINES CONTROLS A NUMBER OF BIOLOGIC PROCESSES SUCH AS IMPRINTING AND X CHROMOSOMAL INACTIVATION. DNA HYPERMETHYLATION IS CLOSELY ASSOCIATED WITH TRANSCRIPTIONAL SILENCING, WHILE DNA HYPOMETHYLATION IS ASSOCIATED WITH TRANSCRIPTIONAL ACTIVATION. HYPOACETYLATION OF HISTONES LEADS TO COMPACT CHROMATIN WITH REDUCED ACCESSIBILITY TO THE TRANSCRIPTIONAL MACHINERY. METHYL-CPG BINDING PROTEINS CAN RECRUIT COREPRESSORS AND HISTONE DEACETYLASES; THUS, THE INTERPLAY BETWEEN THESE EPIGENETIC MECHANISMS REGULATES GENE ACTIVATION. METHYLATION HAS BEEN IMPLICATED AS AN IMPORTANT MECHANISM DURING IMMUNE DEVELOPMENT, CONTROLLING VDJ RECOMBINATION, LINEAGE-SPECIFIC EXPRESSION OF CELL SURFACE ANTIGENS, AND TRANSCRIPTIONAL REGULATION OF CYTOKINE GENES DURING IMMUNE RESPONSES. ABERRATIONS IN EPIGENETIC MACHINERY, EITHER BY GENETIC MUTATIONS OR BY SOMATIC CHANGES SUCH AS VIRAL INFECTIONS, ARE ASSOCIATED WITH EARLY ALTERATIONS IN CHRONIC DISEASES SUCH AS IMMUNODEFICIENCY AND CANCER. 2003 10 332 37 ALTERATION OF EPIGENETIC PROFILE IN HUMAN HEPATOCELLULAR CARCINOMA AND ITS CLINICAL IMPLICATIONS. HEPATOCELLULAR CARCINOMA (HCC) IS A COMMON CANCER WORLDWIDE AND DEVELOPS AGAINST A BACKGROUND OF CHRONIC LIVER DAMAGE. A VARIETY OF HCC-RELATED GENES ARE KNOWN TO BE ALTERED BY GENETIC AND EPIGENETIC MECHANISMS. THEREFORE, INFORMATION REGARDING ALTERATION OF THE GENETIC AND EPIGENETIC PROFILES IN HCC IS ESSENTIAL FOR UNDERSTANDING THE BIOLOGY OF THIS TYPE OF TUMOR. METHYLATION AT CPG SITES IN GENE PROMOTERS IS KNOWN TO AFFECT THE TRANSCRIPTION OF THE CORRESPONDING GENES. ABNORMAL REGIONAL HYPERMETHYLATION IS OBSERVED IN THE 5' REGION OF SEVERAL TUMOR SUPPRESSOR GENES (TSGS) IN HCC, AND THIS HYPERMETHYLATION MAY PROMOTE CARCINOGENESIS THROUGH THE TRANSCRIPTIONAL INACTIVATION OF DOWNSTREAM TSGS. THE DNA DAMAGE INDUCED BY OXIDATION IS A TRIGGER OF ABNORMAL DNA METHYLATION AND INACTIVATION OF TSGS THROUGH RECRUITMENT OF THE POLYCOMB REPRESSIVE COMPLEX TO THE PROMOTER SEQUENCE. THUS, OXIDATIVE STRESS MAY BE RESPONSIBLE FOR THE EMERGENCE OF HCC FROM CHRONIC HEPATITIS AND LIVER CIRRHOSIS THROUGH THE EPIGENETIC ALTERATION OF TSGS. THERE HAVE BEEN SEVERAL ATTEMPTS TO APPLY EPIGENETIC INFORMATION TO THE DIAGNOSIS AND TREATMENT OF HCC. THE PREDICTIVE VALUE OF SELECTED METHYLATION EVENTS ON SURVIVAL IN HCC PATIENTS HAS BEEN REPORTED, AND THE METHYLATION PROFILE OF BACKGROUND LIVER COULD BE ASSOCIATED WITH RECURRENCE-FREE SURVIVAL OF HCC PATIENTS WHO HAVE UNDERGONE HEPATECTOMY. ANOTHER STUDY DETECTED METHYLATED DNA FROM HCC CELLS IN SERUM, AND THE CIRCULATING TUMOR DNA WAS REGARDED AS A POTENTIAL TUMOR MARKER. IN ADDITION, SEVERAL TRIALS OF HCC THERAPY HAVE TARGETED THE EPIGENETIC MACHINERY AND WERE BASED UPON COMPREHENSIVE ANALYSES OF DNA METHYLATION OF THIS TYPE OF TUMOR. HERE, WE PRESENT AN OVERVIEW OF RESEARCH REGARDING DNA METHYLATION STATUS IN HUMAN HCC AND DESCRIBE THE CLINICAL APPLICATION OF EPIGENETIC INFORMATION TO HCC. 2014 11 2002 24 EPIGENETIC AND POST-TRANSCRIPTIONAL REPRESSION SUPPORT METABOLIC SUPPRESSION IN CHRONICALLY HYPOXIC GOLDFISH. GOLDFISH ENTER A HYPOMETABOLIC STATE TO SURVIVE CHRONIC HYPOXIA. WE RECENTLY DESCRIBED TISSUE-SPECIFIC CONTRIBUTIONS OF MEMBRANE LIPID COMPOSITION REMODELING AND MITOCHONDRIAL FUNCTION TO METABOLIC SUPPRESSION ACROSS DIFFERENT GOLDFISH TISSUES. HOWEVER, THE MOLECULAR AND ESPECIALLY EPIGENETIC FOUNDATIONS OF HYPOXIA TOLERANCE IN GOLDFISH UNDER METABOLIC SUPPRESSION ARE NOT WELL UNDERSTOOD. HERE WE SHOW THAT COMPONENTS OF THE MOLECULAR OXYGEN-SENSING MACHINERY ARE ROBUSTLY ACTIVATED ACROSS TISSUES IRRESPECTIVE OF HYPOXIA DURATION. INDUCTION OF GENE EXPRESSION OF ENZYMES INVOLVED IN DNA METHYLATION TURNOVER AND MICRORNA BIOGENESIS SUGGEST A ROLE FOR EPIGENETIC TRANSCRIPTIONAL AND POST-TRANSCRIPTIONAL SUPPRESSION OF GENE EXPRESSION IN THE HYPOXIA-ACCLIMATED BRAIN. CONVERSELY, MECHANISTIC TARGET OF RAPAMYCIN-DEPENDENT TRANSLATIONAL MACHINERY ACTIVITY IS NOT REDUCED IN LIVER AND WHITE MUSCLE, SUGGESTING THIS PATHWAY DOES NOT CONTRIBUTE TO LOWERING CELLULAR ENERGY EXPENDITURE. FINALLY, MOLECULAR EVIDENCE SUPPORTS PREVIOUSLY REPORTED CHRONIC HYPOXIA-DEPENDENT CHANGES IN MEMBRANE CHOLESTEROL, LIPID METABOLISM AND MITOCHONDRIAL FUNCTION VIA CHANGES IN TRANSCRIPTS INVOLVED IN CHOLESTEROL BIOSYNTHESIS, BETA-OXIDATION, AND MITOCHONDRIAL FUSION IN MULTIPLE TISSUES. OVERALL, THIS STUDY SHOWS THAT CHRONIC HYPOXIA ROBUSTLY INDUCES EXPRESSION OF OXYGEN-SENSING MACHINERY ACROSS TISSUES, INDUCES REPRESSIVE TRANSCRIPTIONAL AND POST-TRANSCRIPTIONAL EPIGENETIC MARKS ESPECIALLY IN THE CHRONIC HYPOXIA-ACCLIMATED BRAIN AND SUPPORTS A ROLE FOR MEMBRANE REMODELING AND MITOCHONDRIAL FUNCTION AND DYNAMICS IN PROMOTING METABOLIC SUPPRESSION. 2022 12 1326 18 DEPLETION OF NUCLEAR HISTONE H2A VARIANTS IS ASSOCIATED WITH CHRONIC DNA DAMAGE SIGNALING UPON DRUG-EVOKED SENESCENCE OF HUMAN SOMATIC CELLS. CELLULAR SENESCENCE IS ASSOCIATED WITH GLOBAL CHROMATIN CHANGES, ALTERED GENE EXPRESSION, AND ACTIVATION OF CHRONIC DNA DAMAGE SIGNALING. THESE EVENTS ULTIMATELY LEAD TO MORPHOLOGICAL AND PHYSIOLOGICAL TRANSFORMATIONS IN PRIMARY CELLS. IN THIS STUDY, WE SHOW THAT CHRONIC DNA DAMAGE SIGNALS CAUSED BY GENOTOXIC STRESS IMPACT THE EXPRESSION OF HISTONES H2A FAMILY MEMBERS AND LEAD TO THEIR DEPLETION IN THE NUCLEI OF SENESCENT HUMAN FIBROBLASTS. OUR DATA REINFORCE THE HYPOTHESIS THAT PROGRESSIVE CHROMATIN DESTABILIZATION MAY LEAD TO THE LOSS OF EPIGENETIC INFORMATION AND IMPAIRED CELLULAR FUNCTION ASSOCIATED WITH CHRONIC DNA DAMAGE UPON DRUG-EVOKED SENESCENCE. WE PROPOSE THAT CHANGES IN THE HISTONE BIOSYNTHESIS AND CHROMATIN ASSEMBLY MAY DIRECTLY CONTRIBUTE TO CELLULAR AGING. IN ADDITION, WE ALSO OUTLINE THE METHOD THAT ALLOWS FOR QUANTITATIVE AND UNBIASED MEASUREMENT OF THESE CHANGES. 2012 13 3658 28 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 14 1117 26 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 15 5785 23 SPONTANEOUS NEOPLASTIC TRANSFORMATION OF WB-F344 RAT LIVER EPITHELIAL CELLS. SEVERAL STUDIES HAVE SHOWN THAT CULTURED RAT LIVER EPITHELIAL CELLS TRANSFORM SPONTANEOUSLY AFTER CHRONIC MAINTENANCE IN A CONFLUENT STATE IN VITRO. IN THE PRESENT STUDY, MULTIPLE INDEPENDENT LINEAGES OF LOW-PASSAGE WB-F344 RAT LIVER EPITHELIAL STEM-LIKE CELLS WERE INITIATED AND SUBJECTED IN PARALLEL TO SELECTION FOR SPONTANEOUS TRANSFORMATION TO DETERMINE WHETHER SPONTANEOUS ACQUISITION OF TUMORIGENICITY WAS THE RESULT OF EVENTS (GENETIC OR EPIGENETIC) THAT OCCURRED INDEPENDENTLY AND STOCHASTICALLY, OR REFLECTED THE EXPRESSION OF A PRE-EXISTING ALTERATION WITHIN THE PARENTAL WB-F344 CELL LINE. TEMPORAL ANALYSIS OF THE SPONTANEOUS ACQUISITION OF TUMORIGENICITY BY WB-F344 CELLS DEMONSTRATED LINEAGE-SPECIFIC DIFFERENCES IN THE TIME OF FIRST EXPRESSION OF THE TUMORIGENIC PHENOTYPE, FREQUENCIES AND LATENCIES OF TUMOR FORMATION, AND TUMOR DIFFERENTIATIONS. ALTHOUGH SPONTANEOUSLY TRANSFORMED WB-F344 CELLS PRODUCED DIVERSE TUMOR TYPES (INCLUDING HEPATOCELLULAR CARCINOMAS, CHOLANGIOCARCINOMAS, HEPATOBLASTOMAS, AND OSTEOGENIC SARCOMAS), INDIVIDUAL LINEAGES YIELDED TUMORS WITH CONSISTENT AND SPECIFIC PATTERNS OF DIFFERENTIATION. THESE RESULTS PROVIDE SUBSTANTIAL EVIDENCE THAT THE STOCHASTIC ACCUMULATION OF INDEPENDENT TRANSFORMING EVENTS DURING THE SELECTION REGIMEN IN VITRO WERE RESPONSIBLE FOR SPONTANEOUS NEOPLASTIC TRANSFORMATION OF WB-F344 CELLS. FURTHERMORE, CELL LINEAGE COMMITMENT TO A SPECIFIC DIFFERENTIATION PROGRAM WAS STABLE WITH TIME IN CULTURE AND WITH SITE OF TRANSPLANTATION. THIS IS THE FIRST REPORT OF A COHORT OF RELATED, BUT INDEPENDENT, RAT LIVER EPITHELIAL CELL LINES THAT COLLECTIVELY PRODUCE A SPECTRUM OF TUMOR TYPES BUT INDIVIDUALLY REPRODUCE A SPECIFIC TUMOR TYPE. THESE CELL LINES WILL PROVIDE VALUABLE REAGENTS FOR INVESTIGATION OF THE MOLECULAR MECHANISMS INVOLVED IN THE DIFFERENTIATION OF HEPATIC STEM-LIKE CELLS AND FOR EXAMINATION OF POTENTIAL CAUSAL RELATIONSHIPS IN SPONTANEOUSLY TRANSFORMED RAT LIVER EPITHELIAL CELL LINES BETWEEN MOLECULAR/CELLULAR ALTERATIONS AND THE ABILITY TO PRODUCE TUMORS IN SYNGENEIC ANIMALS. 1998 16 1587 32 DNA METHYLATION PROFILING IDENTIFIES NOVEL MARKERS OF PROGRESSION IN HEPATITIS B-RELATED CHRONIC LIVER DISEASE. BACKGROUND: CHRONIC HEPATITIS B INFECTION IS CHARACTERIZED BY HEPATIC IMMUNE AND INFLAMMATORY RESPONSE WITH CONSIDERABLE VARIATION IN THE RATES OF PROGRESSION TO CIRRHOSIS. GENETIC VARIANTS AND ENVIRONMENTAL CUES INFLUENCE PREDISPOSITION TO THE DEVELOPMENT OF CHRONIC LIVER DISEASE; HOWEVER, IT REMAINS UNKNOWN IF ABERRANT DNA METHYLATION IS ASSOCIATED WITH FIBROSIS PROGRESSION IN CHRONIC HEPATITIS B. RESULTS: TO IDENTIFY EPIGENETIC MARKS ASSOCIATED WITH INFLAMMATORY AND FIBROTIC PROCESSES OF THE HEPATITIS B-INDUCED CHRONIC LIVER DISEASE, WE CARRIED OUT HEPATIC GENOME-WIDE METHYLATION PROFILING USING ILLUMINA INFINIUM BEADARRAYS COMPARING MILD AND SEVERE FIBROTIC DISEASE IN A DISCOVERY COHORT OF 29 PATIENTS. WE OBTAINED 310 DIFFERENTIALLY METHYLATED REGIONS AND SELECTED FOUR LOCI COMPRISING THREE GENES FROM THE TOP DIFFERENTIALLY METHYLATED REGIONS: HYPERMETHYLATION OF HOXA2 AND HDAC4 ALONG WITH HYPOMETHYLATION OF PPP1R18 WERE SIGNIFICANTLY LINKED TO SEVERE FIBROSIS. WE REPLICATED THE PROMINENT METHYLATION MARKS IN AN INDEPENDENT COHORT OF 102 PATIENTS BY BISULFITE MODIFICATION AND PYROSEQUENCING. THE TIMING AND CAUSAL RELATIONSHIP OF EPIGENETIC MODIFICATIONS WITH DISEASE SEVERITY WAS FURTHER INVESTIGATED USING A COHORT OF PATIENTS WITH SERIAL BIOPSIES. CONCLUSIONS: OUR FINDINGS SUGGEST A LINKAGE OF WIDESPREAD EPIGENETIC DYSREGULATION WITH DISEASE PROGRESSION IN CHRONIC HEPATITIS B INFECTION. CPG METHYLATION AT NOVEL GENES SHEDS LIGHT ON NEW MOLECULAR PATHWAYS, WHICH CAN BE POTENTIALLY EXPLOITED AS A BIOMARKER OR TARGETED TO ATTENUATE INFLAMMATION AND FIBROSIS. 2016 17 1567 32 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 18 6707 33 VIRAL HEPATITIS AND HEPATOCELLULAR CARCINOMA: STATE OF THE ART. VIRAL HEPATITIS IS ONE OF THE MAIN CAUSES LEADING TO HEPATOCELLULAR CARCINOMA (HCC). THE CONTINUED RISE IN INCIDENCE OF HCC SUGGESTS ADDITIONAL FACTORS FOLLOWING INFECTION MAY BE INVOLVED. THIS REVIEW EXAMINES RECENT STUDIES INVESTIGATING THE MOLECULAR MECHANISMS OF CHRONIC HEPATITIS AND ITS ASSOCIATION WITH HEPATOCARCINOGENESIS. HEPATITIS B VIRUS PATIENTS WITH GENOTYPE C DISPLAY AN AGGRESSIVE DISEASE COURSE LEADING TO HCC MORE THAN OTHER GENOTYPES. FURTHERMORE, HEPATITIS B EXCRETORY ANTIGEN (HBEAG) SEEMS TO BE A MORE SENSITIVE PREDICTIVE TUMOR MARKER EXHIBITING A SIX-FOLD HIGHER RELATIVE RISK IN PATIENTS WITH POSITIVE HBSAG AND HBEAG THAN THOSE WITH HBSAG ONLY. SINGLE OR COMBINED MUTATIONS OF VIRAL GENOME CAN PREDICT HCC DEVELOPMENT IN UP TO 80% OF PATIENTS. SEVERAL MUTATIONS IN HBX-GENE ARE RELATED WITH HIGHER HCC INCIDENCE. OVEREXPRESSION OF THE CORE PROTEIN IN HCV LEADS TO HEPATOCELLULAR LIPID ACCUMULATION ASSOCIATED WITH ONCOGENESIS. REDUCED NUMBER AND DECREASED FUNCTIONALITY OF NATURAL KILLER CELLS IN CHRONIC HCV INDIVIDUALS DYSREGULATE THEIR SURVEILLANCE FUNCTION IN TUMOR AND VIRAL CELLS RESULTING IN HCC. FURTHERMORE, HIGH T-CELL IMMUNOGLOBULIN AND MUCIN 3 LEVELS SUPRESS CD8+ T-CELLS, WHICH LEAD TO IMMUNOLOGICAL DYSREGULATION. HEPATITIS D PROMOTES HCC DEVELOPMENT INDIRECTLY VIA MODIFICATIONS TO INNATE IMMUNITY, EPIGENETIC ALTERATIONS AND PRODUCTION OF REACTIVE OXYGEN SPECIES WITH THE LHDAG BEING THE MOST HIGHLY ASSOCIATED WITH HCC DEVELOPMENT. SUMMARIZING THE RESULTS, HBV AND HCV INFECTION REPRESENT THE MOST ASSOCIATED FORMS OF VIRAL HEPATITIS CAUSING HCC. FURTHER STUDIES ARE WARRANTED TO FURTHER IMPROVE THE PREDICTION OF HIGH-RISK PATIENTS AND DEVELOPMENT OF TARGETED THERAPEUTICS PREVENTING THE TRANSITION FROM HEPATIC INFLAMMATION-FIBROSIS TO CANCER. 2021 19 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 20 6830 28 [HOW HISTONE DEACETYLASE 3 CONTROLS HEPCIDIN EXPRESSION AND HEPATITIS C VIRUS REPLICATION]. THE KEY ROLE OF HISTONE DEACETYLASES (HDAC) IN THE REGULATION OF THE CELLULAR RESPONSE TO INFECTION WITH THE HEPATITIS C VIRUS (HCV) WAS FIRST DEMONSTRATED IN 2008. WHEN STUDYING THE METABOLISM OF IRON IN THE LIVER TISSUES OF PATIENTS WITH CHRONIC HEPATITIS C, THE AUTHORS FOUND THAT THE EXPRESSION OF THE HEPCIDIN GENE (HAMP), A HORMONE REGULATOR OF IRON EXPORT, IS MARKEDLY REDUCED IN HEPATOCYTES UNDER CONDITIONS OF OXIDATIVE STRESS CAUSED BY VIRAL INFECTION. HDAC WERE INVOLVED IN THE REGULATION OF HEPCIDIN EXPRESSION THROUGH THE CONTROL OF ACETYLATION LEVEL OF HISTONES AND TRANSCRIPTION FACTORS, PRIMARILY STAT3, ASSOCIATED WITH THE HAMP PROMOTER. THE PURPOSE OF THIS REVIEW WAS TO SUMMARIZE CURRENT DATA ON THE FUNCTIONING OF THE HCV-HDAC3-STAT3-HAMP REGULATORY CIRCUIT AS AN EXAMPLE OF A WELL-CHARACTERIZED INTERACTION BETWEEN THE VIRUS AND THE EPIGENETIC APPARATUS OF THE HOST CELL. 2023