1 812 174 CHANGES IN DNA METHYLATION PROFILES OF MYALGIC ENCEPHALOMYELITIS/CHRONIC FATIGUE SYNDROME PATIENTS REFLECT SYSTEMIC DYSFUNCTIONS. BACKGROUND: MYALGIC ENCEPHALOMYELITIS/CHRONIC FATIGUE SYNDROME (ME/CFS) IS A LIFELONG DEBILITATING DISEASE WITH A COMPLEX PATHOLOGY NOT YET CLEARLY DEFINED. SUSCEPTIBILITY TO ME/CFS INVOLVES GENETIC PREDISPOSITION AND EXPOSURE TO ENVIRONMENTAL FACTORS, SUGGESTING AN EPIGENETIC ASSOCIATION. EPIGENETIC STUDIES WITH OTHER ME/CFS COHORTS HAVE USED ARRAY-BASED TECHNOLOGY TO IDENTIFY DIFFERENTIALLY METHYLATED INDIVIDUAL SITES. CHANGES IN RNA QUANTITIES AND PROTEIN ABUNDANCE HAVE BEEN DOCUMENTED IN OUR PREVIOUS INVESTIGATIONS WITH THE SAME ME/CFS COHORT USED FOR THIS STUDY. RESULTS: DNA FROM A WELL-CHARACTERISED NEW ZEALAND COHORT OF 10 ME/CFS PATIENTS AND 10 AGE-/SEX-MATCHED HEALTHY CONTROLS WAS ISOLATED FROM PERIPHERAL BLOOD MONONUCLEAR (PBMC) CELLS, AND USED TO GENERATE REDUCED GENOME-SCALE DNA METHYLATION MAPS USING REDUCED REPRESENTATION BISULPHITE SEQUENCING (RRBS). THE SEQUENCING DATA WERE ANALYSED UTILISING THE DMAP ANALYSIS PIPELINE TO IDENTIFY DIFFERENTIALLY METHYLATED FRAGMENTS, AND THE METHYLKIT PIPELINE WAS USED TO QUANTIFY METHYLATION DIFFERENCES AT INDIVIDUAL CPG SITES. DMAP IDENTIFIED 76 DIFFERENTIALLY METHYLATED FRAGMENTS AND METHYLKIT IDENTIFIED 394 DIFFERENTIALLY METHYLATED CYTOSINES THAT INCLUDED BOTH HYPER- AND HYPO-METHYLATION. FOUR CLUSTERS WERE IDENTIFIED WHERE DIFFERENTIALLY METHYLATED DNA FRAGMENTS OVERLAPPED WITH OR WERE WITHIN CLOSE PROXIMITY TO MULTIPLE DIFFERENTIALLY METHYLATED INDIVIDUAL CYTOSINES. THESE CLUSTERS IDENTIFIED REGULATORY REGIONS FOR 17 PROTEIN ENCODING GENES RELATED TO METABOLIC AND IMMUNE ACTIVITY. ANALYSIS OF DIFFERENTIALLY METHYLATED GENE BODIES (EXONS/INTRONS) IDENTIFIED 122 UNIQUE GENES. COMPARISON WITH OTHER STUDIES ON PBMCS FROM ME/CFS PATIENTS AND CONTROLS WITH ARRAY TECHNOLOGY SHOWED 59% OF THE GENES IDENTIFIED IN THIS STUDY WERE ALSO FOUND IN ONE OR MORE OF THESE STUDIES. FUNCTIONAL PATHWAY ENRICHMENT ANALYSIS IDENTIFIED 30 ASSOCIATED PATHWAYS. THESE INCLUDED IMMUNE, METABOLIC AND NEUROLOGICAL-RELATED FUNCTIONS DIFFERENTIALLY REGULATED IN ME/CFS PATIENTS COMPARED TO THE MATCHED HEALTHY CONTROLS. CONCLUSIONS: MAJOR DIFFERENCES WERE IDENTIFIED IN THE DNA METHYLATION PATTERNS OF ME/CFS PATIENTS THAT CLEARLY DISTINGUISHED THEM FROM THE HEALTHY CONTROLS. OVER HALF FOUND IN GENE BODIES WITH RRBS IN THIS STUDY HAD BEEN IDENTIFIED IN OTHER ME/CFS STUDIES USING THE SAME CELLS BUT WITH ARRAY TECHNOLOGY. WITHIN THE ENRICHED FUNCTIONAL IMMUNE, METABOLIC AND NEUROLOGICAL PATHWAYS, A NUMBER OF ENRICHED NEUROTRANSMITTER AND NEUROPEPTIDE REACTOME PATHWAYS HIGHLIGHTED A DISTURBED NEUROLOGICAL PATHOPHYSIOLOGY WITHIN THE PATIENT GROUP. 2020 2 1132 45 COMPREHENSIVE DNA METHYLATION ANALYSIS USING A METHYL-CPG-BINDING DOMAIN CAPTURE-BASED METHOD IN CHRONIC LYMPHOCYTIC LEUKEMIA PATIENTS. THE ROLE OF LONG NONCODING RNAS (LNCRNAS) IN CANCER IS COMING TO THE FOREFRONT DUE TO GROWING INTEREST IN UNDERSTANDING THEIR MECHANISTIC FUNCTIONS DURING CANCER DEVELOPMENT AND PROGRESSION. DESPITE THIS, THE GLOBAL EPIGENETIC REGULATION OF LNCRNAS AND REPETITIVE SEQUENCES IN CANCER HAS NOT BEEN WELL INVESTIGATED, PARTICULARLY IN CHRONIC LYMPHOCYTIC LEUKEMIA (CLL). THIS STUDY FOCUSES ON A UNIQUE APPROACH: THE IMMUNOPRECIPITATION-BASED CAPTURE OF DOUBLE-STRANDED, METHYLATED DNA FRAGMENTS USING METHYL-BINDING DOMAIN (MBD) PROTEINS, FOLLOWED BY NEXT-GENERATION SEQUENCING (MBD-SEQ). CLL PATIENT SAMPLES BELONGING TO TWO PROGNOSTIC SUBGROUPS (5 IGVH MUTATED SAMPLES + 5 IGVH UNMUTATED SAMPLES) WERE USED IN THIS STUDY. ANALYSIS REVEALED 5,800 HYPERMETHYLATED AND 12,570 HYPOMETHYLATED CLL-SPECIFIC DIFFERENTIALLY METHYLATED GENES (CLLDMGS) COMPARED TO NORMAL HEALTHY CONTROLS. IMPORTANTLY, THESE RESULTS IDENTIFIED SEVERAL CLL-SPECIFIC, DIFFERENTIALLY METHYLATED LNCRNAS, REPETITIVE ELEMENTS, AND PROTEIN-CODING GENES WITH POTENTIAL PROGNOSTIC VALUE. THIS WORK OUTLINES A DETAILED PROTOCOL FOR AN MBD-SEQ AND BIOINFORMATICS PIPELINE DEVELOPED FOR THE COMPREHENSIVE ANALYSIS OF GLOBAL METHYLATION PROFILES IN HIGHLY CPG-RICH REGIONS USING CLL PATIENT SAMPLES. FINALLY, A PROTEIN-CODING GENE AND AN LNCRNA WERE VALIDATED USING PYROSEQUENCING, WHICH IS A HIGHLY QUANTITATIVE METHOD TO ANALYZE CPG METHYLATION LEVELS TO FURTHER CORROBORATE THE FINDINGS FROM THE MBD-SEQ PROTOCOL. 2017 3 3138 47 GLOBAL DNA METHYLATION PROFILING REVEALS NEW INSIGHTS INTO EPIGENETICALLY DEREGULATED PROTEIN CODING AND LONG NONCODING RNAS IN CLL. BACKGROUND: METHYL-CPG-BINDING DOMAIN PROTEIN ENRICHED GENOME-WIDE SEQUENCING (MBD-SEQ) IS A ROBUST AND POWERFUL METHOD FOR ANALYZING METHYLATED CPG-RICH REGIONS WITH COMPLETE GENOME-WIDE COVERAGE. IN CHRONIC LYMPHOCYTIC LEUKEMIA (CLL), THE ROLE OF CPG METHYLATED REGIONS ASSOCIATED WITH TRANSCRIBED LONG NONCODING RNAS (LNCRNA) AND REPETITIVE GENOMIC ELEMENTS ARE POORLY UNDERSTOOD. BASED ON MBD-SEQ, WE CHARACTERIZED THE GLOBAL METHYLATION PROFILE OF HIGH CPG-RICH REGIONS IN DIFFERENT CLL PROGNOSTIC SUBGROUPS BASED ON IGHV MUTATIONAL STATUS. RESULTS: OUR STUDY IDENTIFIED 5800 HYPERMETHYLATED AND 12,570 HYPOMETHYLATED CLL-SPECIFIC DIFFERENTIALLY METHYLATED GENES (CLLDMGS) COMPARED TO NORMAL CONTROLS. FROM CLLDMGS, 40 % OF HYPERMETHYLATED AND 60 % OF HYPOMETHYLATED GENES WERE MAPPED TO NONCODING RNAS. IN ADDITION, WE FOUND THAT THE MAJOR REPETITIVE ELEMENTS SUCH AS SHORT INTERSPERSED ELEMENTS (SINE) AND LONG INTERSPERSED ELEMENTS (LINE) HAVE A HIGH PERCENTAGE OF CLLDMRS (DIFFERENTIALLY METHYLATED REGIONS) IN IGHV SUBGROUPS COMPARED TO NORMAL CONTROLS. FINALLY, TWO NOVEL LNCRNAS (HYPERMETHYLATED CRNDE AND HYPOMETHYLATED AC012065.7) WERE VALIDATED IN AN INDEPENDENT CLL SAMPLE COHORT (48 SAMPLES) COMPARED WITH 6 NORMAL SORTED B CELL SAMPLES USING QUANTITATIVE PYROSEQUENCING ANALYSIS. THE METHYLATION LEVELS SHOWED AN INVERSE CORRELATION TO GENE EXPRESSION LEVELS ANALYZED BY REAL-TIME QUANTITATIVE PCR. NOTABLY, SURVIVAL ANALYSIS REVEALED THAT HYPERMETHYLATION OF CRNDE AND HYPOMETHYLATION OF AC012065.7 CORRELATED WITH AN INFERIOR OUTCOME. CONCLUSIONS: THUS, OUR COMPREHENSIVE METHYLATION ANALYSIS BY MBD-SEQ PROVIDED NOVEL HYPER AND HYPOMETHYLATED LONG NONCODING RNAS, REPETITIVE ELEMENTS, ALONG WITH PROTEIN CODING GENES AS POTENTIAL EPIGENETIC-BASED CLL-SIGNATURE GENES INVOLVED IN DISEASE PATHOGENESIS AND PROGNOSIS. 2016 4 2771 41 EXTENSIVE PROMOTER DNA HYPERMETHYLATION AND HYPOMETHYLATION IS ASSOCIATED WITH ABERRANT MICRORNA EXPRESSION IN CHRONIC LYMPHOCYTIC LEUKEMIA. DYSREGULATED MICRORNA (MIRNA) EXPRESSION CONTRIBUTES TO THE PATHOGENESIS OF HEMATOPOIETIC MALIGNANCIES, INCLUDING CHRONIC LYMPHOCYTIC LEUKEMIA (CLL). HOWEVER, AN UNDERSTANDING OF THE MECHANISMS THAT CAUSE ABERRANT MIRNA TRANSCRIPTIONAL CONTROL IS LACKING. IN THIS STUDY, WE COMPREHENSIVELY INVESTIGATED THE ROLE AND EXTENT OF MIRNA EPIGENETIC REGULATION IN CLL. GENOME-WIDE PROFILING CONDUCTED ON 24 CLL AND 10 HEALTHY B CELL SAMPLES REVEALED GLOBAL DNA METHYLATION PATTERNS UPSTREAM OF MIRNA SEQUENCES THAT DISTINGUISHED MALIGNANT FROM HEALTHY CELLS AND IDENTIFIED PUTATIVE MIRNA PROMOTERS. INTEGRATION OF DNA METHYLATION AND MIRNA PROMOTER DATA LED TO THE IDENTIFICATION OF 128 RECURRENT MIRNA TARGETS FOR ABERRANT PROMOTER DNA METHYLATION. DNA HYPOMETHYLATION ACCOUNTED FOR MORE THAN 60% OF ALL ABERRANT PROMOTER-ASSOCIATED DNA METHYLATION IN CLL, AND PROMOTER DNA HYPOMETHYLATION WAS RESTRICTED TO WELL-DEFINED REGIONS. INDIVIDUAL HYPER- AND HYPOMETHYLATED PROMOTERS ALLOWED DISCRIMINATION OF CLL SAMPLES FROM HEALTHY CONTROLS. PROMOTER DNA METHYLATION PATTERNS WERE CONFIRMED IN AN INDEPENDENT PATIENT COHORT, WITH 11 MIRNAS CONSISTENTLY SHOWING AN INVERSE CORRELATION BETWEEN DNA METHYLATION STATUS AND EXPRESSION LEVEL. TOGETHER, OUR FINDINGS CHARACTERIZE THE ROLE OF EPIGENETIC CHANGES IN THE REGULATION OF MIRNA TRANSCRIPTION AND CREATE A REPOSITORY OF DISEASE-SPECIFIC PROMOTER REGIONS THAT MAY PROVIDE ADDITIONAL INSIGHTS INTO THE PATHOGENESIS OF CLL. 2012 5 4014 37 LOW-DOSE CD INDUCES HEPATIC GENE HYPERMETHYLATION, ALONG WITH THE PERSISTENT REDUCTION OF CELL DEATH AND INCREASE OF CELL PROLIFERATION IN RATS AND MICE. BACKGROUND: CADMIUM (CD) IS CLASSIFIED AS A HUMAN CARCINOGEN PROBABLY ASSOCIATED WITH EPIGENETIC CHANGES. DNA METHYLATION IS ONE OF EPIGENETIC MECHANISMS BY WHICH CELLS CONTROL GENE EXPRESSION. THEREFORE, THE PRESENT STUDY GENOME-WIDELY SCREENED THE METHYLATION-ALTERED GENES IN THE LIVER OF RATS PREVIOUSLY EXPOSED TO LOW-DOSE CD. METHODOLOGY PRINCIPAL FINDINGS: RATS WERE EXPOSED TO CD AT 20 NMOL/KG EVERY OTHER DAY FOR 4 WEEKS AND GENE METHYLATION WAS ANALYZED AT THE 48(TH) WEEK WITH METHYLATED DNA IMMUNOPRECIPITATION-CPG ISLAND MICROARRAY. AMONG THE 1629 ALTERED GENES, THERE WERE 675 GENES WHOSE PROMOTER CPG ISLANDS (CGIS) WERE HYPERMETHYLATED, 899 GENES WHOSE PROMOTER CGIS WERE HYPOMETHYLATED, AND 55 GENES WHOSE PROMOTER CGIS WERE MIXED WITH HYPER- AND HYPO-METHYLATION. CASPASE-8 GENE PROMOTER CGIS AND TNF GENE PROMOTER CGIS WERE HYPERMETHYLATED AND HYPOMETHYLATED, RESPECTIVELY, ALONG WITH A LOW APOPTOSIS RATE IN CD-TREATED RAT LIVERS. TO LINK THE ABERRANT METHYLATION OF CASPASE-8 AND TNF GENES TO THE LOW APOPTOSIS INDUCED BY LOW-DOSE CD, MICE WERE GIVEN CHRONIC EXPOSURE TO LOW-DOSE CD WITH AND WITHOUT METHYLATION INHIBITOR (5-AZA-2'-DEOXYCTIDENE, 5-AZA). AT THE 48(TH) WEEK AFTER CD EXPOSURE, LIVERS FROM CD-TREATED MICE DISPLAYED THE INCREASED CASPASE-8 CGI METHYLATION AND DECREASED CASPASE-8 PROTEIN EXPRESSION, ALONG WITH SIGNIFICANT INCREASES IN CELL PROLIFERATION AND OVEREXPRESSION OF TGF-BETA1 AND CYTOKERATIN 8/18 (THE LATTER IS A NEW MARKER OF MOUSE LIVER PRENEOPLASTIC LESIONS), ALL WHICH WERE PREVENTED BY 5-AZA TREATMENT. CONCLUSION/SIGNIFICANCE: THESE RESULTS SUGGEST THAT CD-INDUCED GLOBAL GENE HYPERMETHYLATION, MOST LIKELY CASPASE-8 GENE PROMOTER HYPERMETHYLATION THAT DOWN-REGULATED ITS EXPRESSION, LEADING TO THE DECREASED HEPATIC APOPTOSIS AND INCREASED PRENEOPLASTIC LESIONS. 2012 6 1161 54 CONTINUOUS DEVELOPMENTAL AND EARLY LIFE TRICHLOROETHYLENE EXPOSURE PROMOTED DNA METHYLATION ALTERATIONS IN POLYCOMB PROTEIN BINDING SITES IN EFFECTOR/MEMORY CD4(+) T CELLS. TRICHLOROETHYLENE (TCE) IS AN INDUSTRIAL SOLVENT AND DRINKING WATER POLLUTANT ASSOCIATED WITH CD4(+) T CELL-MEDIATED AUTOIMMUNITY. IN OUR MOUSE MODEL, DISCONTINUATION OF TCE EXPOSURE DURING ADULTHOOD AFTER DEVELOPMENTAL EXPOSURE DID NOT PREVENT IMMUNOTOXICITY. TO DETERMINE WHETHER PERSISTENT EFFECTS WERE LINKED TO EPIGENETIC CHANGES WE CONDUCTED WHOLE GENOME REDUCED REPRESENTATION BISULFITE SEQUENCING (RRBS) TO EVALUATE METHYLATION OF CPG SITES IN AUTOSOMAL CHROMOSOMES IN ACTIVATED EFFECTOR/MEMORY CD4(+) T CELLS. FEMALE MRL+/+ MICE WERE EXPOSED TO VEHICLE CONTROL OR TCE IN THE DRINKING WATER FROM GESTATION UNTIL ~37 WEEKS OF AGE [POSTNATAL DAY (PND) 259]. IN A SUBSET OF MICE, TCE EXPOSURE WAS DISCONTINUED AT ~22 WEEKS OF AGE (PND 154). AT PND 259, RRBS ASSESSMENT REVEALED MORE GLOBAL METHYLATION CHANGES IN THE CONTINUOUS EXPOSURE GROUP VS. THE DISCONTINUOUS EXPOSURE GROUP. A MAJORITY OF THE DIFFERENTIALLY METHYLATED CPG REGIONS (DMRS) ACROSS PROMOTERS, ISLANDS, AND REGULATORY ELEMENTS WERE HYPERMETHYLATED (~90%). HOWEVER, CONTINUOUS DEVELOPMENTAL TCE EXPOSURE ALTERED THE METHYLATION OF 274 CPG SITES IN PROMOTERS AND CPG ISLANDS. IN CONTRAST, ONLY 4 CPG ISLAND REGIONS WERE DIFFERENTIALLY METHYLATED (HYPERMETHYLATED) IN THE DISCONTINUOUS GROUP. INTERESTINGLY, 2 OF THESE 4 SITES WERE ALSO HYPERMETHYLATED IN THE CONTINUOUS EXPOSURE GROUP, AND BOTH OF THESE ISLAND REGIONS ARE ASSOCIATED WITH LYSINE 27 ON HISTONE H3 (H3K27) INVOLVED IN POLYCOMB COMPLEX-DEPENDENT TRANSCRIPTIONAL REPRESSION VIA H3K27 TRI-METHYLATION. CPG SITES WERE OVERLAPPED WITH THE OPEN REGULATORY ANNOTATION DATABASE. UNLIKE THE DISCONTINUOUS GROUP, CONTINUOUS TCE TREATMENT RESULTED IN 129 DMRS INCLUDING 12 UNIQUE TRANSCRIPTION FACTORS AND REGULATORY ELEMENTS; 80% OF WHICH WERE ENRICHED FOR ONE OR MORE POLYCOMB GROUP (PCG) PROTEIN BINDING REGIONS (I.E., SUZ12, EZH2, JARID2, AND MTF2). PATHWAY ANALYSIS OF THE DMRS INDICATED THAT TCE PRIMARILY ALTERED THE METHYLATION OF GENES ASSOCIATED WITH REGULATION OF CELLULAR METABOLISM AND CELL SIGNALING. THE RESULTS DEMONSTRATED THAT CONTINUOUS DEVELOPMENTAL EXPOSURE TO TCE DIFFERENTIALLY METHYLATED BINDING SITES OF PCG PROTEINS IN EFFECTOR/MEMORY CD4(+) CELLS. THERE WERE MINIMAL YET POTENTIALLY BIOLOGICALLY SIGNIFICANT EFFECTS THAT OCCURRED WHEN EXPOSURE WAS DISCONTINUED. THESE RESULTS POINT TOWARD A NOVEL MECHANISM BY WHICH CHRONIC DEVELOPMENTAL TCE EXPOSURE MAY ALTER TERMINALLY DIFFERENTIATED CD4(+) T CELL FUNCTION IN ADULTHOOD. 2019 7 6845 41 [METHYLATION STATUS OF APOPTOSIS GENES AND INTENSITY OF APOPTOTIC DEATH OF PERIPHERAL BLOOD LYMPHOCYTES IN PERSONS CHRONICALLY EXPOSED TO RADIATION]. METHYLATION OF THE CPG ISLANDS OF GENE PROMOTER REGIONS IS THE MOST COMMON EPIGENETIC MODIFICATION INVOLVED IN THE REGULATION OF GENE EXPRESSION. A NUMBER OF STUDIES HAVE SHOWN THAT IONIZING RADIATION CAN CAUSE BOTH HYPER- AND HYPOMETHYLATION OF DNA. ABERRANT METHYLATION AFFECTS CELLULAR PROCESSES AND CAN LEAD TO THE DEVELOPMENT OF VARIOUS PATHOLOGICAL STATES. IN THE LITERATURE, THERE ARE FEW STUDIES ON THE METHYLATION STATUS OF HUMAN DNA A LONG TIME AFTER RADIATION EXPOSURE. HERE, THE METHYLATION LEVEL OF CPG ISLANDS OF THE PROMOTER REGIONS OF APOPTOSIS GENES (BCL2, ATM, MDM2, CDKN1A, STAT3, AND NFKB1), AND ALSO ITS INFLUENCE ON APOPTOSIS OF PERIPHERAL BLOOD LYMPHOCYTES IN CHRONICALLY EXPOSED PERSONS WERE STUDIED. RESIDENTS OF THE SOUTH URAL REGION WHO WERE CHRONICALLY EXPOSED TO RADIATION (AFTER DISCHARGES OF RADIOACTIVE WASTES INTO THE TECHA RIVER BY THE "MAYAK PRODUCTION ASSOCIATION" IN 1949-1956) WERE INCLUDED IN THE STUDY. IT WAS ESTABLISHED THAT THE PROPORTION OF INDIVIDUALS WITH HYPERMETHYLATED BCL2 GENE PROMOTER AMONG THE EXPOSED PEOPLE WAS STATISTICALLY SIGNIFICANTLY HIGHER THAN IN THE CONTROL GROUP. THE PERCENTAGE OF METHYLATION OF THE ATM GENE PROMOTER WEAKLY POSITIVELY CORRELATED WITH DOSE AND AGE CHARACTERISTICS. DIFFERENCES IN THE FREQUENCY OF LYMPHOCYTE APOPTOSIS IN EXPOSED INDIVIDUALS WITH A HYPO- OR HYPERMETHYLATED ATM GENE PROMOTER WERE ALSO ESTABLISHED. THE DATA INDICATE THAT, IN THE LONG-TERM, AFTER CHRONIC LOW INTENSITY RADIATION EXPOSURE AT LOW AND MEDIUM DOSES, EPIGENETIC MODIFICATIONS OF THE GENOME OCCUR, WHICH ARE MANIFESTED AS CHANGES IN METHYLATION OF PROMOTER REGIONS OF BCL2 AND ATM GENES. 2022 8 5555 36 ROLE OF FLUORIDE INDUCED EPIGENETIC ALTERATIONS IN THE DEVELOPMENT OF SKELETAL FLUOROSIS. FLUORIDE IS AN ESSENTIAL TRACE ELEMENT REQUIRED FOR PROPER BONE AND TOOTH DEVELOPMENT. SYSTEMIC HIGH EXPOSURE TO FLUORIDE THROUGH ENVIRONMENTAL EXPOSURE (DRINKING WATER AND FOOD) MAY RESULT IN TOXICITY CAUSING A DISORDER CALLED FLUOROSIS. IN THE PRESENT STUDY, WE INVESTIGATED THE ALTERATION IN DNA METHYLATION PROFILE WITH CHRONIC EXPOSURE (30 DAYS) TO FLUORIDE (8 MG/L) AND ITS RELEVANCE IN THE DEVELOPMENT OF FLUOROSIS. WHOLE GENOME BISULFITE SEQUENCING (WGBS) WAS CARRIED OUT IN HUMAN OSTEOSARCOMA CELLS (HOS) EXPOSED TO FLUORIDE. WHOLE GENOME BISULFITE SEQUENCING (WGBS) AND FUNCTIONAL ANNOTATION OF DIFFERENTIALLY METHYLATED GENES INDICATE ALTERATIONS IN METHYLATION STATUS OF GENES INVOLVED IN BIOLOGICAL PROCESSES ASSOCIATED WITH BONE DEVELOPMENT PATHWAYS. COMBINED ANALYSIS OF PROMOTER DNA HYPER METHYLATION, STRING: FUNCTIONAL PROTEIN ASSOCIATION NETWORKS AND GENE EXPRESSION ANALYSIS REVEALED EPIGENETIC ALTERATIONS IN BMP1, METAP2, MMP11 AND BACH1 GENES, WHICH PLAYS A ROLE IN THE EXTRACELLULAR MATRIX DISASSEMBLY, COLLAGEN CATABOLIC/ORGANIZATION PROCESS, SKELETAL MORPHOGENESIS/DEVELOPMENT, OSSIFICATION AND OSTEOBLAST DEVELOPMENT. THE PRESENT STUDY SHOWS THAT FLUORIDE CAUSES PROMOTER DNA HYPERMETHYLATION IN BMP1, METAP2, MMP11 AND BACH1 GENES WITH SUBSEQUENT DOWN-REGULATION IN THEIR EXPRESSION LEVEL (RNA LEVEL). THE RESULTS IMPLIES THAT FLUORIDE INDUCED DNA HYPERMETHYLATION OF THESE GENES MAY HAMPER EXTRACELLULAR MATRIX DEPOSITION, CARTILAGE FORMATION, ANGIOGENESIS, VASCULAR SYSTEM DEVELOPMENT AND POROSITY OF BONE, THUS PROMOTE SKELETAL FLUOROSIS. 2019 9 3056 51 GENOME-WIDE DNA METHYLATION ANALYSIS IMPLICATES ENRICHMENT OF INTERFERON PATHWAY IN AFRICAN AMERICAN PATIENTS WITH SYSTEMIC LUPUS ERYTHEMATOSUS AND EUROPEAN AMERICANS WITH LUPUS NEPHRITIS. SYSTEMIC LUPUS ERYTHEMATOSUS (SLE) IS A CHRONIC, MULTISYSTEM, INFLAMMATORY AUTOIMMUNE DISEASE THAT DISPROPORTIONATELY AFFECTS WOMEN. TRENDS IN SLE PREVALENCE AND CLINICAL COURSE DIFFER BY ANCESTRY, WITH THOSE OF AFRICAN AMERICAN ANCESTRY PRESENTING WITH MORE ACTIVE, SEVERE AND RAPIDLY PROGRESSIVE DISEASE THAN EUROPEAN AMERICANS. PREVIOUS RESEARCH ESTABLISHED ALTERED EPIGENETIC SIGNATURES IN SLE PATIENTS COMPARED TO CONTROLS. HOWEVER, THE CONTRIBUTION OF ABERRANT DNA METHYLATION (DNAM) TO THE RISK OF SLE BY ANCESTRY AND DIFFERENCES AMONG PATIENTS WITH SLE-ASSOCIATED LUPUS NEPHRITIS (LN) HAS NOT BEEN WELL DESCRIBED. WE EVALUATED THE DNA METHYLOMES OF 87 INDIVIDUALS INCLUDING 41 SLE PATIENTS, WITH AND WITHOUT LN, AND 46 CONTROLS ENROLLED IN AN ANCESTRY DIVERSE, WELL-CHARACTERIZED COHORT STUDY OF ESTABLISHED SLE (41 SLE PATIENTS [20 SLE-LN+, 21 SLE-LN-] AND 46 SEX-, RACE- AND AGE-MATCHED CONTROLS; 55% AFRICAN AMERICAN, 45% EUROPEAN AMERICAN). PARTICIPANTS WERE GENOTYPED USING THE INFINIUM GLOBAL DIVERSITY ARRAY (GDA), AND GENETIC ANCESTRY WAS ESTIMATED USING PRINCIPAL COMPONENTS. GENOME-WIDE DNA METHYLATION WAS INITIALLY MEASURED USING THE ILLUMINA METHYLATIONEPIC 850K BEADCHIP ARRAY FOLLOWED BY METHYLATION-SPECIFIC QPCR TO VALIDATE THE METHYLATION STATUS AT PUTATIVE LOCI. DIFFERENTIALLY METHYLATED POSITIONS (DMP) WERE IDENTIFIED USING A CASE-CONTROL APPROACH ADJUSTED FOR ANCESTRY. WE IDENTIFIED A TOTAL OF 51 DMPS IN CPGS AMONG SLE PATIENTS COMPARED TO CONTROLS. GENES PROXIMAL TO THESE CPGS WERE HIGHLY ENRICHED FOR INVOLVEMENT IN TYPE I INTERFERON SIGNALING. DMPS AMONG EUROPEAN AMERICAN SLE PATIENTS WITH LN WERE SIMILAR TO AFRICAN AMERICAN SLE PATIENTS WITH AND WITHOUT LN. OUR FINDINGS WERE VALIDATED USING AN ORTHOGONAL, METHYL-SPECIFIC PCR FOR THREE SLE-ASSOCIATED DMPS NEAR OR PROXIMAL TO MX1, USP18, AND IFITM1. OUR STUDY CONFIRMS PREVIOUS REPORTS THAT DMPS IN CPGS ASSOCIATED WITH SLE ARE ENRICHED IN TYPE I INTERFERON GENES. HOWEVER, WE SHOW THAT EUROPEAN AMERICAN SLE PATIENTS WITH LN HAVE SIMILAR DNAM PATTERNS TO AFRICAN AMERICAN SLE PATIENTS IRRESPECTIVE OF LN, SUGGESTING THAT ABERRANT DNAM ALTERS ACTIVITY OF TYPE I INTERFERON PATHWAY LEADING TO MORE SEVERE DISEASE INDEPENDENT OF ANCESTRY. 2023 10 3099 37 GENOMIC DNA METHYLATION SIGNATURES IN DIFFERENT TISSUES AFTER AMBIENT AIR PARTICULATE MATTER EXPOSURE. DNA METHYLATION (5-MC) IS ONE OF THE SEVERAL EPIGENETIC MARKERS, AND IS GENERALLY ASSOCIATED WITH THE INHIBITION OF GENE EXPRESSION. BOTH HYPER AND HYPO DNA METHYLATION ARE ASSOCIATED WITH THE DISEASES. EXPOSURE TO FINE PARTICLES WITH A DIAMETER OF 2.5 MUM OR LESS (PM(2.5)) IS A PERVASIVE RISK FACTOR FOR CARDIOPULMONARY MORTALITY, METABOLIC DISORDERS, COGNITION DAMAGE, AND ETC.. RECENT REPORTS POINTED TOWARD THAT THESE DISEASES WERE ASSOCIATED WITH THE ALTERED DNA METHYLATION LEVEL OF SOME SPECIFIC-GENE, POTENTIALLY SUGGESTING THAT THE DNA METHYLATION ALTERATION WAS INVOLVED IN THE HEALTH HAZARD DERIVED FROM THE PM(2.5) EXPOSURE. IN THIS STUDY, WE SYSTEMATICALLY INVESTIGATED THE GLOBAL DNA METHYLATION LEVEL OF MOST TISSUES, INCLUDING LUNG, HEART, TESTIS, THYMUS, SPLEEN, EPIDIDYMAL FAT, HIPPOCAMPUS, KIDNEY, LIVE, AFTER SHORT AND LONG TERM PM(2.5) EXPOSURE. AFTER ACUTE PM(2.5) EXPOSURE, THE GLOBAL HYPO-METHYLATION IN DNA WAS OBSERVED IN LUNG AND HEART. NOTABLY, AFTER CHRONIC PM(2.5) EXPOSURE, LEVEL OF GLOBAL DNA METHYLATION DECREASED IN MOST ORGANS WHICH INCLUDED LUNG, TESTIS, THYMUS, SPLEEN, EPIDIDYMAL FAT, HIPPOCAMPUS AND BLOOD. THE PRESENT STUDY SYSTEMATICALLY DEMONSTRATED THE GLOBAL DNA METHYLATION CHANGES BY PM(2.5) EXPOSURE, AND PUT FORWARD A POSSIBLE ORIENTATION FOR FURTHER EXPLORING THE EFFECTS OF AMBIENT AIR PARTICLES EXPOSURE ON THE SPECIFIC ORGANS. 2019 11 2682 32 EVALUATION OF SERUM LINE-1 HYPOMETHYLATION AS A PROGNOSTIC MARKER FOR HEPATOCELLULAR CARCINOMA. BACKGROUND AND STUDY AIMS: GLOBAL HYPOMETHYLATION IS ONE OF THE MOST CONSISTENT EPIGENETIC CHANGES IN CANCER. DEVELOPMENT OF HEPATOCELLULAR CARCINOMA (HCC) MUST BE UNDERSTOOD AS A MULTISTEP PROCESS WITH ACCUMULATION OF GENETIC AND EPIGENETIC ALTERATIONS. IN THE LAST DECADES, IN ADDITION TO GENETIC ALTERATIONS, EPIGENETIC CHANGES HAVE BEEN RECOGNIZED AS AN IMPORTANT AND ALTERNATIVE MECHANISM IN TUMOURIGENESIS. WE INVESTIGATED THE CLINICAL IMPLICATIONS OF GLOBAL HYPOMETHYLATION IN THE SERA OF PATIENTS WITH HEPATOCELLULAR CARCINOMA (HCC). PATIENTS AND METHODS: PCR WAS USED TO ASSESS THE METHYLATION STATUS OF LONG INTERSPERSED NUCLEAR ELEMENT TYPE 1 (LINE-1) REPETITIVE SEQUENCES IN GENOMIC DNA DERIVED FROM SERA OF 50 PATIENTS WITH HCC, 20 PATIENTS WITH CIRRHOSIS, 20 PATIENTS WITH CHRONIC HEPATITIS C AND 10 HEALTHY SUBJECTS. RESULTS: SERUM GENOME HYPOMETHYLATION WAS SIGNIFICANTLY INCREASED IN PATIENTS WITH HCC (P<0.001). THE LEVELS OF SERUM LINE-1 HYPOMETHYLATION AT INITIAL PRESENTATION CORRELATED SIGNIFICANTLY WITH TUMOUR SIZE, TUMOUR NUMBER AND ALPHA-FOETOPROTEIN LEVEL. MOREOVER HIGH SERUM LINE-1 HYPOMETHYLATION CORRELATES SIGNIFICANTLY WITH POOR SURVIVAL. CONCLUSION: SERUM LINE-1 HYPOMETHYLATION MAY SERVE AS A PROGNOSTIC MARKER FOR PATIENTS WITH HCC. 2011 12 3496 67 IDENTIFICATION OF MYALGIC ENCEPHALOMYELITIS/CHRONIC FATIGUE SYNDROME-ASSOCIATED DNA METHYLATION PATTERNS. BACKGROUND: MYALGIC ENCEPHALOMYELITIS/CHRONIC FATIGUE SYNDROME (ME/CFS) IS A COMPLEX CONDITION INVOLVING MULTIPLE ORGAN SYSTEMS AND CHARACTERIZED BY PERSISTENT/RELAPSING DEBILITATING FATIGUE, IMMUNE DYSFUNCTION, NEUROLOGICAL PROBLEMS, AND OTHER SYMPTOMS NOT CURABLE FOR AT LEAST 6 MONTHS. DISRUPTION OF DNA METHYLATION PATTERNS HAS BEEN TIED TO VARIOUS IMMUNE AND NEUROLOGICAL DISEASES; HOWEVER, ITS STATUS IN ME/CFS REMAINS UNCERTAIN. OUR STUDY AIMED AT IDENTIFYING CHANGES IN THE DNA METHYLATION PATTERNS THAT ASSOCIATE WITH ME/CFS. METHODS: WE EXTRACTED GENOMIC DNA FROM PERIPHERAL BLOOD MONONUCLEAR CELLS FROM 13 ME/CFS STUDY SUBJECTS AND 12 HEALTHY CONTROLS AND MEASURED GLOBAL DNA METHYLATION BY ELISA-LIKE METHOD AND SITE-SPECIFIC METHYLATION STATUS USING ILLUMINA METHYLATIONEPIC MICROARRAYS. PYROSEQUENCING VALIDATION INCLUDED 33 ME/CFS CASES AND 31 CONTROLS FROM TWO GEOGRAPHICALLY DISTANT COHORTS. RESULTS: GLOBAL DNA METHYLATION LEVELS OF ME/CFS CASES WERE SIMILAR TO THOSE OF CONTROLS. HOWEVER, MICROARRAY-BASED APPROACH ALLOWED DETECTION OF 17,296 DIFFERENTIALLY METHYLATED CPG SITES IN 6,368 GENES ACROSS REGULATORY ELEMENTS AND WITHIN CODING REGIONS OF GENES. ANALYSIS OF DNA METHYLATION IN PROMOTER REGIONS REVEALED 307 DIFFERENTIALLY METHYLATED PROMOTERS. INGENUITY PATHWAY ANALYSIS INDICATED THAT GENES ASSOCIATED WITH DIFFERENTIALLY METHYLATED PROMOTERS PARTICIPATED IN AT LEAST 15 DIFFERENT PATHWAYS MOSTLY RELATED TO CELL SIGNALING WITH A STRONG IMMUNE COMPONENT. CONCLUSIONS: THIS IS THE FIRST STUDY THAT HAS EXPLORED GENOME-WIDE EPIGENETIC CHANGES ASSOCIATED WITH ME/CFS USING THE ADVANCED ILLUMINA METHYLATIONEPIC MICROARRAYS COVERING ABOUT 850,000 CPG SITES IN TWO GEOGRAPHICALLY DISTANT COHORTS OF ME/CFS CASES AND MATCHED CONTROLS. OUR RESULTS ARE ALIGNED WITH PREVIOUS STUDIES THAT INDICATE A DYSREGULATION OF THE IMMUNE SYSTEM IN ME/CFS. THEY ALSO SUGGEST A POTENTIAL ROLE OF EPIGENETIC DE-REGULATION IN THE PATHOBIOLOGY OF ME/CFS. WE PROPOSE SCREENING OF LARGER COHORTS OF ME/CFS CASES TO DETERMINE THE EXTERNAL VALIDITY OF THESE EPIGENETIC CHANGES IN ORDER TO IMPLEMENT THEM AS POSSIBLE DIAGNOSTIC MARKERS IN CLINICAL SETTING. 2018 13 5556 34 ROLE OF FLUORIDE INDUCED HISTONE TRIMETHYLATION IN DEVELOPMENT OF SKELETAL FLUOROSIS. CHRONIC EXPOSURE TO FLUORIDE HAS BEEN ASSOCIATED WITH THE DEVELOPMENT OF SKELETAL FLUOROSIS. LIMITED REPORTS ARE AVAILABLE ON FLUORIDE INDUCED HISTONE MODIFICATION. HOWEVER, THE ROLE OF HISTONE MODIFICATION IN THE PATHOGENESIS OF SKELETAL FLUOROSIS IS NOT INVESTIGATED. IN THE PRESENT STUDY, WE HAVE INVESTIGATED THE ROLE OF FLUORIDE INDUCED HISTONE MODIFICATION ON FLUOROSIS DEVELOPMENT USING HUMAN OSTEOSARCOMA (HOS) CELL LINE. THE EXPRESSION OF HISTONE METHYLTRANSFERASES (EHMT1 AND EHZ2) AND LEVEL OF GLOBAL HISTONE TRIMETHYLATION (H3K9 AND H3K27) HAVE BEEN ASSESSED AND OBSERVED TO BE INCREASED SIGNIFICANTLY AFTER FLUORIDE EXPOSURE (8 MG/L). EPITECT CHROMATIN IMMUNOPRECIPITATION (CHIP) QPCR ARRAY (HUMAN TGFBETA/BMP SIGNALING PATHWAY) WAS PERFORMED TO ASSESS THE H3K9 TRIMETHYLATION AT PROMOTER REGIONS OF PATHWAY-SPECIFIC GENES. H3K9 CHIP PCR ARRAY ANALYSIS IDENTIFIED HYPER H3K9 TRIMETHYLATION IN PROMOTER REGIONS OF TGFBR2 AND SMAD3. QPCR AND STRING ANALYSIS WAS CARRIED OUT TO DETERMINE THE REPRESSIVE EPIGENETIC EFFECT OF H3K9 TRIMETHYLATION ON EXPRESSION PATTERN AND FUNCTIONAL ASSOCIATION OF IDENTIFIED GENES. IDENTIFIED GENES (TGFBR2 AND SMAD3) SHOWED DOWN-REGULATION WHICH CONFIRMS THE REPRESSIVE EPIGENETIC EFFECT OF PROMOTER H3K9 HYPER TRIMETHYLATION. EXPRESSION OF TWO OTHER VITAL GENES COL1A1 AND MMP13 INVOLVED IN TGFBR2-SMAD SIGNALING PATHWAY WAS ALSO FOUND TO BE DOWN-REGULATED WITH A DECREASE IN EXPRESSION OF TGFBR2 AND SMAD3. STRING ANALYSIS REVEALED FUNCTIONAL ASSOCIATION AND INVOLVEMENT OF IDENTIFIED GENES TGFBR2, SMAD3, COL1A1 AND MMP13 IN THE COLLAGEN AND CARTILAGE DEVELOPMENT/MORPHOGENESIS, CONNECTIVE TISSUE FORMATION, BIO-MINERAL TISSUE DEVELOPMENT, ENDOCHONDRAL BONE FORMATION, BONE AND SKELETAL MORPHOGENESIS. IN CONCLUSION, PRESENT INVESTIGATION IS A FIRST ATTEMPT TO LINK FLUORIDE INDUCED HYPER H3K9 TRI-METHYLATION MEDIATED REPRESSION OF TGFBR2 AND SMAD3 WITH THE DEVELOPMENT OF SKELETAL FLUOROSIS. 2018 14 6748 46 WHOLE GENOME METHYLATION ARRAY ANALYSIS REVEALS NEW ASPECTS IN BALKAN ENDEMIC NEPHROPATHY ETIOLOGY. BACKGROUND: BALKAN ENDEMIC NEPHROPATHY (BEN) REPRESENTS A CHRONIC PROGRESSIVE INTERSTITIAL NEPHRITIS IN STRIKING CORRELATION WITH UROEPITHELIAL TUMOURS OF THE UPPER URINARY TRACT. THE DISEASE HAS ENDEMIC DISTRIBUTION IN THE DANUBE RIVER REGIONS IN SEVERAL BALKAN COUNTRIES.DNA METHYLATION IS A PRIMARY EPIGENETIC MODIFICATION THAT IS INVOLVED IN MAJOR PROCESSES SUCH AS CANCER, GENOMIC IMPRINTING, GENE SILENCING, ETC. THE SIGNIFICANCE OF CPG ISLAND METHYLATION STATUS IN NORMAL DEVELOPMENT, CELL DIFFERENTIATION AND GENE EXPRESSION IS WIDELY RECOGNIZED, ALTHOUGH STILL STAYS POORLY UNDERSTOOD. METHODS: WE PERFORMED WHOLE GENOME DNA METHYLATION ARRAY ANALYSIS ON DNA POOL SAMPLES FROM PERIPHERAL BLOOD FROM 159 AFFECTED INDIVIDUALS AND 170 HEALTHY INDIVIDUALS. THIS TECHNIQUE ALLOWED US TO DETERMINE THE METHYLATION STATUS OF 27 627 CPG ISLANDS THROUGHOUT THE WHOLE GENOME IN HEALTHY CONTROLS AND BEN PATIENTS. THUS WE OBTAINED THE METHYLATION PROFILE OF BEN PATIENTS FROM BULGARIAN AND SERBIAN ENDEMIC REGIONS. RESULTS: USING SPECIFICALLY DEVELOPED SOFTWARE WE COMPARED THE METHYLATION PROFILES OF BEN PATIENTS AND CORRESPONDING CONTROLS AND REVEALED THE DIFFERENTLY METHYLATED REGIONS. WE THEN COMPARED THE DMRS BETWEEN ALL PATIENT-CONTROL PAIRS TO DETERMINE COMMON CHANGES IN THE EPIGENETIC PROFILES.SEC61G, IL17RA, HDAC11 PROVED TO BE DIFFERENTLY METHYLATED THROUGHOUT ALL PATIENT-CONTROL PAIRS. THE CPG ISLANDS OF ALL 3 GENES WERE HYPOMETHYLATED COMPARED TO CONTROLS. THIS SUGGESTS THAT DYSREGULATION OF THESE GENES INVOLVED IN IMMUNOLOGICAL RESPONSE COULD BE A COMMON MECHANISM IN BEN PATHOGENESIS IN BOTH ENDEMIC REGIONS AND IN BOTH GENDERS. CONCLUSION: OUR DATA PROPOSE A NEW HYPOTHESIS THAT IMMUNOLOGIC DYSREGULATION HAS A PLACE IN BEN ETIOPATHOGENESIS. 2013 15 3455 46 HYPOMETHYLATION COORDINATES ANTAGONISTICALLY WITH HYPERMETHYLATION IN CANCER DEVELOPMENT: A CASE STUDY OF LEUKEMIA. BACKGROUND: METHYLATION CHANGES ARE FREQUENT IN CANCERS, BUT UNDERSTANDING HOW HYPER- AND HYPOMETHYLATED REGION CHANGES COORDINATE, ASSOCIATE WITH GENOMIC FEATURES, AND AFFECT GENE EXPRESSION IS NEEDED TO BETTER UNDERSTAND THEIR BIOLOGICAL SIGNIFICANCE. THE FUNCTIONAL SIGNIFICANCE OF HYPERMETHYLATION IS WELL STUDIED, BUT THAT OF HYPOMETHYLATION REMAINS LIMITED. HERE, WITH PAIRED EXPRESSION AND METHYLATION SAMPLES GATHERED FROM A PATIENT/CONTROL COHORT, WE ATTEMPT TO BETTER CHARACTERIZE THE GENE EXPRESSION AND METHYLATION CHANGES THAT TAKE PLACE IN CANCER FROM B CELL CHRONIC LYMPHOCYTE LEUKEMIA (B-CLL) SAMPLES. RESULTS: ACROSS THE DATASET, WE FOUND THAT CONSISTENT DIFFERENTIALLY HYPOMETHYLATED REGIONS (C-DMRS) ACROSS SAMPLES WERE RELATIVELY FEW COMPARED TO THE MANY POORLY CONSISTENT HYPO- AND HIGHLY CONSERVED HYPER-DMRS. HOWEVER, GENES IN THE HYPO-C-DMRS TENDED TO BE ASSOCIATED WITH FUNCTIONS ANTAGONISTIC TO THOSE IN THE HYPER-C-DMRS, LIKE DIFFERENTIATION, CELL-CYCLE REGULATION AND PROLIFERATION, SUGGESTING COORDINATED REGULATION OF METHYLATION CHANGES. HYPO-C-DMRS IN B-CLL WERE FOUND ENRICHED IN KEY SIGNALING PATHWAYS LIKE B CELL RECEPTOR AND P53 PATHWAYS AND GENES/MOTIFS ESSENTIAL FOR B LYMPHOPOIESIS. HYPO-C-DMRS TENDED TO BE PROXIMAL TO GENES WITH ELEVATED EXPRESSION IN CONTRAST TO THE TRANSCRIPTION SILENCING-MECHANISM IMPOSED BY HYPERMETHYLATION. HYPO-C-DMRS TENDED TO BE ENRICHED IN THE REGIONS OF ACTIVATING H4K4ME1/2/3, H3K79ME2, AND H3K27AC HISTONE MODIFICATIONS. IN COMPARISON, THE POLYCOMB REPRESSIVE COMPLEX 2 (PRC2) SIGNATURE, MARKED BY EZH2, SUZ12, CTCF BINDING-SITES, REPRESSIVE H3K27ME3 MARKS, AND "REPRESSED/POISED PROMOTER" STATES WERE ASSOCIATED WITH HYPER-C-DMRS. MOST HYPO-C-DMRS WERE FOUND IN INTRONS (36 %), 3' UNTRANSLATED REGIONS (29 %), AND INTERGENIC REGIONS (24 %). MANY OF THESE GENIC REGIONS ALSO OVERLAPPED WITH ENHANCERS. THE METHYLATION OF CPGS FROM 3'UTR EXONS WAS FOUND TO HAVE WEAK BUT POSITIVE CORRELATION WITH GENE EXPRESSION. IN CONTRAST, METHYLATION IN THE 5'UTR WAS NEGATIVELY CORRELATED WITH EXPRESSION. TO BETTER CHARACTERIZE THE OVERLAP BETWEEN METHYLATION AND EXPRESSION CHANGES, WE IDENTIFIED CORRELATION MODULES THAT ASSOCIATE WITH "APOPTOSIS" AND "LEUKOCYTE ACTIVATION". CONCLUSIONS: DESPITE CLINICAL HETEROGENEITY IN DISEASE PRESENTATION, A NUMBER OF METHYLATION CHANGES, BOTH HYPO AND HYPER, APPEAR TO BE COMMON IN B-CLL. HYPOMETHYLATION APPEARS TO PLAY AN ACTIVE, TARGETED, AND COMPLEMENTARY ROLE IN CANCER PROGRESSION, AND IT INTERPLAYS WITH HYPERMETHYLATION IN A COORDINATED FASHION IN THE CANCER PROCESS. 2016 16 3046 42 GENOME-WIDE ANALYSIS OF DNA METHYLATION IDENTIFIES S100A13 AS AN EPIGENETIC BIOMARKER IN INDIVIDUALS WITH CHRONIC (>/= 30 YEARS) TYPE 2 DIABETES WITHOUT DIABETIC RETINOPATHY. BACKGROUND: THIS STUDY AIMED TO DETERMINE THE EPIGENETIC BIOMARKERS OF DIABETIC RETINOPATHY (DR) IN SUBJECTS WITH TYPE 2 DIABETES MELLITUS (T2DM). THIS RETROSPECTIVE STUDY IS BASED ON THE SHANGHAI XINJING COMMUNITY PREVENTION AND TREATMENT ADMINISTRATIVE SYSTEM OF CHRONIC DISEASES. THE SUBJECTS ENROLLED HEREIN WERE T2DM PATIENTS WHO HAD UNDERGONE LONG-TERM FOLLOW-UP EVALUATION IN THE SYSTEM. TWO CONSECUTIVE STUDIES WERE CONDUCTED. IN THE DISCOVERY COHORT, AMONG 19 SUBJECTS WHO HAD DEVELOPED DR WITH A DM DURATION < 3 YEARS AND 21 SUBJECTS WITHOUT DR > 30 YEARS AFTER BEING DIAGNOSED WITH DM, AN INFINIUM HUMAN METHYLATION 850 BEADCHIP WAS USED TO IDENTIFY DIFFERENTIAL METHYLATION REGIONS (DMRS) AND DIFFERENTIAL METHYLATION SITES (DMSS). THE FUNCTION OF THE GENES WAS ASSESSED THROUGH KEGG ENRICHMENT ANALYSIS, GENE ONTOLOGY (GO) ANALYSIS, AND PATHWAY NETWORK ANALYSIS. IN THE REPLICATION COHORT, 87 DR PATIENTS WITH A SHORT DM DURATION AND 89 PATIENTS WITHOUT DR OVER A DM DURATION > 20 YEARS WERE COMPARED TO ASSESS THE ASSOCIATION BETWEEN DMSS AND DR UPON PYROSEQUENCING. RESULTS: A TOTAL OF 34 DMRS WERE IDENTIFIED. GENES CONTAINING DMSS WITH THE TOP 5 HIGHEST BETA VALUE DIFFERENCES BETWEEN DR AND NON-DR PARTICIPANTS WERE LOCATED ON CHROMOSOME 1 AND WERE PRESENT IN THE S100A13 GENE, WHICH WAS ASSOCIATED WITH 71 GO TERMS. TWO S100A13 GENE SITES, I.E., CG02873163 AND CG11343894, DISPLAYED A GOOD CORRELATION WITH DR ON PYROSEQUENCING. CONCLUSIONS: DMSS IN THE S100A13 GENE MAY BE POTENTIAL BIOMARKERS OF DR. 2020 17 2639 33 EPIGENOMIC ANALYSIS DETECTS WIDESPREAD GENE-BODY DNA HYPOMETHYLATION IN CHRONIC LYMPHOCYTIC LEUKEMIA. WE HAVE EXTENSIVELY CHARACTERIZED THE DNA METHYLOMES OF 139 PATIENTS WITH CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) WITH MUTATED OR UNMUTATED IGHV AND OF SEVERAL MATURE B-CELL SUBPOPULATIONS THROUGH THE USE OF WHOLE-GENOME BISULFITE SEQUENCING AND HIGH-DENSITY MICROARRAYS. THE TWO MOLECULAR SUBTYPES OF CLL HAVE DIFFERING DNA METHYLOMES THAT SEEM TO REPRESENT EPIGENETIC IMPRINTS FROM DISTINCT NORMAL B-CELL SUBPOPULATIONS. DNA HYPOMETHYLATION IN THE GENE BODY, TARGETING MOSTLY ENHANCER SITES, WAS THE MOST FREQUENT DIFFERENCE BETWEEN NAIVE AND MEMORY B CELLS AND BETWEEN THE TWO MOLECULAR SUBTYPES OF CLL AND NORMAL B CELLS. ALTHOUGH DNA METHYLATION AND GENE EXPRESSION WERE POORLY CORRELATED, WE IDENTIFIED GENE-BODY CPG DINUCLEOTIDES WHOSE METHYLATION WAS POSITIVELY OR NEGATIVELY ASSOCIATED WITH EXPRESSION. WE HAVE ALSO RECOGNIZED A DNA METHYLATION SIGNATURE THAT DISTINGUISHES NEW CLINICO-BIOLOGICAL SUBTYPES OF CLL. WE PROPOSE AN EPIGENOMIC SCENARIO IN WHICH DIFFERENTIAL METHYLATION IN THE GENE BODY MAY HAVE FUNCTIONAL AND CLINICAL IMPLICATIONS IN LEUKEMOGENESIS. 2012 18 2633 51 EPIGENOME-WIDE DNA METHYLATION PATTERNS ASSOCIATED WITH FATIGUE IN PRIMARY SJOGREN'S SYNDROME. OBJECTIVE: CHRONIC FATIGUE IS A COMMON, DISABLING AND POORLY UNDERSTOOD PHENOMENON. RECENT STUDIES INDICATE THAT EPIGENETIC MECHANISMS MAY BE INVOLVED IN THE EXPRESSION OF FATIGUE, A PROMINENT FEATURE OF PRIMARY SS (PSS). THE AIM OF THIS STUDY WAS TO INVESTIGATE WHETHER DNA METHYLATION PROFILES OF WHOLE BLOOD ARE ASSOCIATED WITH FATIGUE IN PATIENTS WITH PSS. METHODS: FORTY-EIGHT PSS PATIENTS WITH HIGH (N = 24) OR LOW (N = 24) FATIGUE AS MEASURED BY A VISUAL ANALOGUE SCALE WERE INCLUDED. GENOME-WIDE DNA METHYLATION WAS INVESTIGATED USING THE ILLUMINA HUMANMETHYLATION450 BEADCHIP ARRAY. AFTER QUALITY CONTROL, A TOTAL OF 383 358 CYTOSINE-PHOSPHATE-GUANINE (CPG) SITES REMAINED FOR FURTHER ANALYSIS. AGE, SEX AND DIFFERENTIAL CELL COUNT ESTIMATES WERE INCLUDED AS COVARIATES IN THE ASSOCIATION MODEL. A FALSE DISCOVERY RATE-CORRECTED P < 0.05 WAS CONSIDERED SIGNIFICANT, AND A CUT-OFF OF 3% AVERAGE DIFFERENCE IN METHYLATION LEVELS BETWEEN HIGH- AND LOW-FATIGUE PATIENTS WAS APPLIED. RESULTS: A TOTAL OF 251 DIFFERENTIALLY METHYLATED CPG SITES WERE ASSOCIATED WITH FATIGUE. THE CPG SITE WITH THE MOST PRONOUNCED HYPOMETHYLATION IN PSS HIGH FATIGUE ANNOTATED TO THE SBF2-ANTISENSE RNA1 GENE. THE MOST DISTINCT HYPERMETHYLATION WAS OBSERVED AT A CPG SITE ANNOTATED TO THE LYMPHOTOXIN ALPHA GENE. FUNCTIONAL PATHWAY ANALYSIS OF GENES WITH DIFFERENTLY METHYLATED CPG SITES IN SUBJECTS WITH HIGH VS LOW FATIGUE REVEALED ENRICHMENT IN SEVERAL PATHWAYS ASSOCIATED WITH INNATE AND ADAPTIVE IMMUNITY. CONCLUSION: SOME GENES INVOLVED IN REGULATION OF THE IMMUNE SYSTEM AND IN INFLAMMATION ARE DIFFERENTLY METHYLATED IN PSS PATIENTS WITH HIGH VS LOW FATIGUE. THESE FINDINGS POINT TO FUNCTIONAL NETWORKS THAT MAY UNDERLIE FATIGUE. EPIGENETIC CHANGES COULD CONSTITUTE A FATIGUE-REGULATING MECHANISM IN PSS. 2016 19 5744 33 SMOKING-INDUCED EXPRESSION OF THE GPR15 GENE INDICATES ITS POTENTIAL ROLE IN CHRONIC INFLAMMATORY PATHOLOGIES. DESPITE THE DESCRIBED CLEAR EPIGENETIC EFFECTS OF SMOKING, THE EFFECT OF SMOKING ON GENOME-WIDE GENE EXPRESSION IN THE BLOOD IS OBSCURE. WE THEREFORE STUDIED THE SMOKING-INDUCED CHANGES IN THE GENE-EXPRESSION PROFILE OF THE PERIPHERAL BLOOD. RNA WAS EXTRACTED FROM THE WHOLE BLOOD OF 48 INDIVIDUALS WITH A DETAILED SMOKING HISTORY (24 NEVER-SMOKERS, 16 SMOKERS, AND 8 EX-SMOKERS). GENE-EXPRESSION PROFILES WERE EVALUATED WITH RNA SEQUENCING, AND RESULTS WERE ANALYZED SEPARATELY IN 24 MEN AND 24 WOMEN. IN THE MALE SMOKERS, 13 GENES WERE STATISTICALLY SIGNIFICANTLY (FALSE-DISCOVERY RATE <0.1) DIFFERENTIALLY EXPRESSED; IN FEMALE SMOKERS, 5 GENES. ALTHOUGH MOST OF THE DIFFERENTIALLY EXPRESSED GENES WERE DIFFERENT BETWEEN THE MALE AND FEMALE SMOKERS, THE G-PROTEIN-COUPLED RECEPTOR 15 GENE (GPR15) WAS DIFFERENTIALLY EXPRESSED IN BOTH MALE AND FEMALE SMOKERS COMPARED WITH NEVER-SMOKERS. ANALYSIS OF GPR15 METHYLATION IDENTIFIED SIGNIFICANTLY GREATER HYPOMETHYLATION IN SMOKERS COMPARED WITH THAT IN NEVER-SMOKERS. GPR15 IS THE CHEMOATTRACTANT RECEPTOR THAT REGULATES T-CELL MIGRATION AND IMMUNITY. UP-REGULATION OF GPR15 COULD EXPLAIN TO SOME EXTENT THE HEALTH HAZARDS OF SMOKING WITH REGARD TO CHRONIC INFLAMMATORY DISEASES. 2015 20 2418 51 EPIGENETIC SIGNATURE OF CHRONIC LOW BACK PAIN IN HUMAN T CELLS. OBJECTIVE: DETERMINE IF CHRONIC LOW BACK PAIN (LBP) IS ASSOCIATED WITH DNA METHYLATION SIGNATURES IN HUMAN T CELLS THAT WILL REVEAL NOVEL MECHANISMS AND POTENTIAL THERAPEUTIC TARGETS AND EXPLORE THE FEASIBILITY OF EPIGENETIC DIAGNOSTIC MARKERS FOR PAIN-RELATED PATHOPHYSIOLOGY. METHODS: GENOME-WIDE DNA METHYLATION ANALYSIS OF 850,000 CPG SITES IN WOMEN AND MEN WITH CHRONIC LBP AND PAIN-FREE CONTROLS WAS PERFORMED. T CELLS WERE ISOLATED (DISCOVERY COHORT, N = 32) AND USED TO IDENTIFY DIFFERENTIALLY METHYLATED CPG SITES, AND GENE ONTOLOGIES AND MOLECULAR PATHWAYS WERE IDENTIFIED. A POLYGENIC DNA METHYLATION SCORE FOR LBP WAS GENERATED IN BOTH WOMEN AND MEN. VALIDATION WAS PERFORMED IN AN INDEPENDENT COHORT (VALIDATION COHORT, N = 63) OF CHRONIC LBP AND HEALTHY CONTROLS. RESULTS: ANALYSIS WITH THE DISCOVERY COHORT REVEALED A TOTAL OF 2,496 AND 419 DIFFERENTIALLY METHYLATED CPGS IN WOMEN AND MEN, RESPECTIVELY. IN WOMEN, MOST OF THESE SITES WERE HYPOMETHYLATED AND ENRICHED IN GENES WITH FUNCTIONS IN THE EXTRACELLULAR MATRIX, IN THE IMMUNE SYSTEM (IE, CYTOKINES), OR IN EPIGENETIC PROCESSES. IN MEN, A UNIQUE CHRONIC LBP DNA METHYLATION SIGNATURE WAS IDENTIFIED CHARACTERIZED BY SIGNIFICANT ENRICHMENT FOR GENES FROM THE MAJOR HISTOCOMPATIBILITY COMPLEX. SEX-SPECIFIC POLYGENIC DNA METHYLATION SCORES WERE GENERATED TO ESTIMATE THE PAIN STATUS OF EACH INDIVIDUAL AND CONFIRMED IN THE VALIDATION COHORT USING PYROSEQUENCING. CONCLUSION: THIS STUDY REVEALS SEX-SPECIFIC DNA METHYLATION SIGNATURES IN HUMAN T CELLS THAT DISCRIMINATES CHRONIC LBP PARTICIPANTS FROM HEALTHY CONTROLS. 2021