1 3066 131 GENOME-WIDE DNA METHYLATION PATTERNS IN CD4+ T CELLS FROM PATIENTS WITH SYSTEMIC LUPUS ERYTHEMATOSUS. SYSTEMIC LUPUS ERYTHEMATOSUS IS A CHRONIC-RELAPSING AUTOIMMUNE DISEASE OF INCOMPLETELY UNDERSTOOD ETIOLOGY. RECENT EVIDENCE STRONGLY SUPPORTS AN EPIGENETIC CONTRIBUTION TO THE PATHOGENESIS OF LUPUS. TO UNDERSTAND THE EXTENT AND NATURE OF DYSREGULATED DNA METHYLATION IN LUPUS T CELLS, WE PERFORMED A GENOME-WIDE DNA METHYLATION STUDY IN CD4 (+) T CELLS IN LUPUS PATIENTS COMPARED TO NORMAL HEALTHY CONTROLS. CYTOSINE METHYLATION WAS QUANTIFIED IN 27,578 CG SITES LOCATED WITHIN THE PROMOTER REGIONS OF 14,495 GENES. WE IDENTIFIED 236 HYPOMETHYLATED AND 105 HYPERMETHYLATED CG SITES IN LUPUS CD4 (+) T CELLS COMPARED TO NORMAL CONTROLS, CONSISTENT WITH WIDESPREAD DNA METHYLATION CHANGES IN LUPUS T CELLS. OF INTEREST, HYPOMETHYLATED GENES IN LUPUS T CELLS INCLUDE CD9, WHICH IS KNOWN TO PROVIDE POTENT T-CELL CO-STIMULATION SIGNALS. OTHER GENES WITH KNOWN INVOLVEMENT IN AUTOIMMUNITY SUCH AS MMP9 AND PDGFRA WERE ALSO HYPOMETHYLATED. THE BST2 GENE, AN INTERFERON-INDUCIBLE MEMBRANE-BOUND PROTEIN THAT HELPS RESTRICT THE RELEASE OF RETROVIRAL PARTICLES WAS ALSO HYPOMETHYLATED IN LUPUS PATIENTS. GENES INVOLVED IN FOLATE BIOSYNTHESIS, WHICH PLAYS A ROLE IN DNA METHYLATION, WERE OVERREPRESENTED AMONG HYPERMETHYLATED GENES. IN ADDITION, THE TRANSCRIPTION FACTOR RUNX3 WAS HYPERMETHYLATED IN PATIENTS, SUGGESTING AN IMPACT ON T-CELL MATURATION. PROTEIN-PROTEIN INTERACTION MAPS IDENTIFIED A TRANSCRIPTION FACTOR, HNF4A, AS A REGULATORY HUB AFFECTING A NUMBER OF DIFFERENTIALLY METHYLATED GENES. APOPTOSIS WAS ALSO AN OVERREPRESENTED ONTOLOGY IN THESE INTERACTION MAPS. FURTHER, OUR DATA SUGGEST THAT THE METHYLATION STATUS OF RAB22A, STX1B2, LGALS3BP, DNASE1L1 AND PREX1 CORRELATES WITH DISEASE ACTIVITY IN LUPUS PATIENTS. 2011 2 1739 42 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 3 6826 41 [GENOME-WIDE ANALYSIS OF DNA METHYLATION IN CD4+ T LYMPHOCYTES OF PATIENTS WITH PRIMARY PROGRESSIVE MULTIPLE SCLEROSIS INDICATES INVOLVEMENT OF THIS EPIGENETIC PROCESS IN THE DISEASE IMMUNOPATHOGENESIS]. THE PATHOGENESIS OF MULTIPLE SCLEROSIS (MS), A CHRONIC DISEASE OF THE CNS, INCLUDES AUTOIMMUNE AND NEURODEGENERATIVE COMPONENTS. IN MOST CASES, PATIENTS DEVELOP RELAPSING-REMITTING MS (RRMS), WHILE 10-15% OF PATIENTS DEVELOP PRIMARY PROGRESSIVE MS (PPMS), WHICH DIFFERS FROM RRMS IN THE MECHANISMS OF THE PATHOLOGICAL PROCESS, SOME DEMOGRAPHIC, AND SOME CLINICAL CHARACTERISTICS. THESE DIFFERENCES MAY BE EXPLAINED BY THE EPIGENETIC REGULATION OF GENE EXPRESSION IN PPMS INCLUDING DNA METHYLATION AS ONE OF THE KEY EPIGENETIC PROCESSES. THE FEATURES OF DNA METHYLATION IN VARIOUS CELL POPULATIONS IN PPMS PATIENTS REMAIN UNDERSTUDIED. THE GOAL OF THIS STUDY IS TO IDENTIFY DIFFERENTIALLY METHYLATED CPG SITES (DMSS) OF THE GENOME OF CD4+ T LYMPHOCYTES, WHICH CHARACTERIZE PPMS. THE STUDY INCLUDED EIGHT TREATMENT-NAIVE PPMS PATIENTS AND EIGHT HEALTHY CONTROLS. GENOME-WIDE ANALYSIS OF DNA METHYLATION OF CD4+ T LYMPHOCYTES WAS PERFORMED USING HIGH-DENSITY DNA MICROARRAYS. WE HAVE IDENTIFIED 108 DMSS, WHICH DISTINGUISH PPMS PATIENTS FROM HEALTHY CONTROLS. IN PPMS PATIENTS 81% OF THE DMSS ARE HYPERMETHYLATED. MORE THAN A HALF OF THE IDENTIFIED DMSS ARE LOCATED IN KNOWN GENES IN CPG ISLANDS AND ADJACENT REGIONS, WHICH INDICATES A HIGH FUNCTIONAL SIGNIFICANCE OF THESE DMSS IN PPMS DEVELOPMENT. ANALYSIS OF THE OVERREPRESENTATION OF DMS-CONTAINING GENES IN THE MAIN BIOLOGICAL PROCESSES DEMONSTRATES THEIR INVOLVEMENT IN THE REGULATION OF CELL ADHESION TO THE EXTRACELLULAR MATRIX AND THE DEVELOPMENT OF THE IMMUNE RESPONSE, I.E., ANTIGEN PROCESSING AND PRESENTATION, AND DEVELOPMENT OF THE IMMUNE SYSTEM. GENOME-WIDE ANALYSIS OF DNA METHYLATION IN CD4+ T LYMPHOCYTES OF PPMS PATIENTS INDICATES THE INVOLVEMENT OF THIS EPIGENETIC PROCESS IN THE IMMUNOPATHOGENESIS OF THE DISEASE. THESE RESULTS MAY HELP BETTER UNDERSTAND THE PATHOGENESIS OF THIS SEVERE FORM OF MS. 2022 4 1584 28 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 5 1508 50 DNA METHYLATION AND MRNA AND MICRORNA EXPRESSION OF SLE CD4+ T CELLS CORRELATE WITH DISEASE PHENOTYPE. SYSTEMIC LUPUS ERYTHEMATOSUS (SLE) IS AN AUTOIMMUNE DISEASE WELL KNOWN FOR ITS CLINICAL HETEROGENEITY, AND ITS ETIOLOGY SECONDARY TO A CROSS-TALK INVOLVING GENETIC PREDISPOSITION AND ENVIRONMENTAL STIMULI. ALTHOUGH GENOME-WIDE ANALYSIS HAS CONTRIBUTED GREATLY TO OUR UNDERSTANDING OF THE GENETIC BASIS OF SLE, THERE IS INCREASING EVIDENCE FOR A ROLE OF EPIGENETICS. INDEED, RECENT DATA HAVE DEMONSTRATED THAT IN PATIENTS WITH SLE, THERE ARE STRIKING ALTERATIONS OF DNA METHYLATION, HISTONE MODIFICATIONS, AND DEREGULATED MICRORNA EXPRESSION, THE SUM OF WHICH CONTRIBUTE TO OVER-EXPRESSION OF SELECT AUTOIMMUNE-RELATED GENES AND LOSS OF TOLERANCE. TO ADDRESS THIS ISSUE AT THE LEVEL OF CLINICAL PHENOTYPE, WE PERFORMED DNA METHYLATION, MRNA AND MICRORNA EXPRESSION SCREENING USING HIGH-THROUGHPUT SEQUENCING OF PURIFIED CD4+ T CELLS FROM PATIENTS WITH SLE, COMPARED TO AGE AND SEX MATCHED CONTROLS. IN PARTICULAR, WE STUDIED 42 PATIENTS WITH SLE AND DIVIDED THIS GROUP INTO THREE CLINICAL PHENOTYPES: A) THE PRESENCE OF SKIN LESIONS WITHOUT SIGNS OF SYSTEMIC PATHOLOGY; B) SKIN LESIONS BUT ALSO CHRONIC RENAL PATHOLOGY; AND C) SKIN LESIONS, CHRONIC RENAL PATHOLOGY AND POLYARTICULAR DISEASE. INTERESTINGLY, AND AS EXPECTED, SEQUENCING DATA REVEALED CHANGES IN DNA METHYLATION IN SLE COMPARED TO CONTROLS. HOWEVER, AND MORE IMPORTANTLY, ALTHOUGH THERE WERE COMMON METHYLATION CHANGES FOUND IN ALL GROUPS OF SLE COMPARED TO CONTROLS, THERE WAS SPECIFIC DNA METHYLATION CHANGES THAT CORRELATED WITH CLINICAL PHENOTYPE. THESE INCLUDED CHANGES IN THE NOVEL KEY TARGET GENES NLRP2, CD300LB AND S1PR3, AS WELL AS CHANGES IN THE CRITICAL PATHWAYS, INCLUDING THE ADHERENS JUNCTION AND LEUKOCYTE TRANSENDOTHELIAL MIGRATION. WE ALSO NOTED THAT A SIGNIFICANT PROPORTION OF GENES UNDERGOING DNA METHYLATION CHANGES WERE INVERSELY CORRELATED WITH GENE EXPRESSION AND THAT MIRNA SCREENING REVEALED THE EXISTENCE OF SUBSETS WITH CHANGES IN EXPRESSION. INTEGRATED ANALYSIS OF THIS DATA HIGHLIGHTS SPECIFIC SETS OF MIRNAS CONTROLLED BY DNA METHYLATION, AND GENES THAT ARE ALTERED BY METHYLATION AND TARGETED BY MIRNAS. IN CONCLUSION, OUR FINDINGS SUGGEST SELECT EPIGENETIC MECHANISMS THAT CONTRIBUTE TO CLINICAL PHENOTYPES AND FURTHER SHED LIGHT ON A NEW VENUE FOR BASIC SLE RESEARCH. 2014 6 2635 43 EPIGENOME-WIDE DNA METHYLATION REGULATES CARDINAL PATHOLOGICAL FEATURES OF PSORIASIS. BACKGROUND: PSORIASIS IS A CHRONIC INFLAMMATORY AUTOIMMUNE SKIN DISORDER. SEVERAL STUDIES SUGGESTED PSORIASIS TO BE A COMPLEX MULTIFACTORIAL DISEASE, BUT THE EXACT TRIGGERING FACTOR IS YET TO BE DETERMINED. EVIDENCES SUGGEST THAT IN ADDITION TO GENETIC FACTORS, EPIGENETIC REPROGRAMMING IS ALSO INVOLVED IN PSORIASIS DEVELOPMENT. MAJOR HISTOPATHOLOGICAL FEATURES, LIKE INCREASED PROLIFERATION AND ABNORMAL DIFFERENTIATION OF KERATINOCYTES, AND IMMUNE CELL INFILTRATIONS ARE CHARACTERISTIC MARKS OF PSORIATIC SKIN LESIONS. FOLLOWING THERAPY, HISTOPATHOLOGICAL FEATURES AS WELL AS ABERRANT DNA METHYLATION REVERSED TO NORMAL LEVELS. TO UNDERSTAND THE ROLE OF DNA METHYLATION IN REGULATING THESE CRUCIAL HISTOPATHOLOGIC FEATURES, WE INVESTIGATED THE GENOME-WIDE DNA METHYLATION PROFILE OF PSORIASIS PATIENTS WITH DIFFERENT HISTOPATHOLOGICAL FEATURES. RESULTS: GENOME-WIDE DNA METHYLATION PROFILING OF PSORIATIC AND ADJACENT NORMAL SKIN TISSUES IDENTIFIED SEVERAL NOVEL DIFFERENTIALLY METHYLATED REGIONS ASSOCIATED WITH PSORIASIS. DIFFERENTIALLY METHYLATED CPGS WERE SIGNIFICANTLY ENRICHED IN SEVERAL PSORIASIS SUSCEPTIBILITY (PSORS) REGIONS AND EPIGENETICALLY REGULATED THE EXPRESSION OF KEY PATHOGENIC GENES, EVEN WITH LOW-CPG PROMOTERS. TOP DIFFERENTIALLY METHYLATED GENES OVERLAPPED WITH PSORS REGIONS INCLUDING S100A9, SELENBP1, CARD14, KAZN AND PTPN22 SHOWED INVERSE CORRELATION BETWEEN METHYLATION AND GENE EXPRESSION. WE IDENTIFIED DIFFERENTIALLY METHYLATED GENES ASSOCIATED WITH CHARACTERISTIC HISTOPATHOLOGICAL FEATURES IN PSORIASIS. PSORIATIC SKIN WITH MUNRO'S MICROABSCESS, A DISTINCTIVE FEATURE IN PSORIASIS INCLUDING PARAKERATOSIS AND NEUTROPHIL ACCUMULATION AT THE STRATUM CORNEUM, WAS ENRICHED WITH DIFFERENTIALLY METHYLATED GENES INVOLVED IN NEUTROPHIL CHEMOTAXIS. RETE PEG ELONGATION AND FOCAL HYPERGRANULOSIS WERE ALSO ASSOCIATED WITH EPIGENETICALLY REGULATED GENES, SUPPORTING THE REVERSIBLE NATURE OF THESE CHARACTERISTIC FEATURES DURING REMISSION AND RELAPSE OF THE LESIONS. CONCLUSION: OUR STUDY, FOR THE FIRST TIME, INDICATED THE POSSIBLE INVOLVEMENT OF DNA METHYLATION IN REGULATING THE CARDINAL PATHOPHYSIOLOGICAL FEATURES IN PSORIASIS. COMMON GENES INVOLVED IN REGULATION OF THESE PATHOLOGIES MAY BE USED TO DEVELOP DRUGS FOR BETTER CLINICAL MANAGEMENT OF PSORIASIS. 2018 7 1297 38 DECREASED MRNA EXPRESSION LEVELS OF DNA METHYLTRANSFERASES TYPE 1 AND 3A IN SYSTEMIC LUPUS ERYTHEMATOSUS. OBJECTIVES: SYSTEMIC LUPUS ERYTHEMATOSUS (SLE) IS A CHRONIC RELAPSING AUTOIMMUNE DISEASE CHARACTERIZED BY THE PRESENCE OF AUTOANTIBODIES DIRECTED AGAINST NUCLEAR ANTIGENS AND BY CHRONIC INFLAMMATION. ALTHOUGH THE ETIOLOGY OF SLE REMAINS UNCLEAR, THE INFLUENCE OF ENVIRONMENT FACTORS, WHICH IS LARGELY REFLECTED BY THE EPIGENETIC MECHANISMS, WITH DNA METHYLATION CHANGES IN PARTICULAR, IS GENERALLY CONSIDERED AS MAIN PLAYERS IN THE PATHOGENESIS OF SLE. WE STUDIED DNA METHYLTRANSFERASES' (DNMTS) TYPE 1, 3A AND 3B TRANSCRIPT LEVELS IN PERIPHERAL BLOOD MONONUCLEAR CELLS FROM PATIENTS DIAGNOSED WITH SYSTEMIC LUPUS ERYTHEMATOSUS AND FROM THE HEALTHY CONTROL SUBJECTS. FURTHERMORE, THE ASSOCIATION OF DNMT1, DNMT3A, AND DNMT3B MRNA LEVELS WITH GENDER, AGE, AND MAJOR CLINICAL MANIFESTATIONS WAS ANALYZED. METHODS: PERIPHERAL BLOOD MONONUCLEAR CELLS (PBMCS) WERE ISOLATED FROM 32 SLE PATIENTS AND 40 HEALTHY CONTROLS. REVERSE TRANSCRIPTION AND REAL-TIME QUANTITATIVE POLYMERASE CHAIN REACTION (RT-QPCR) ANALYSES WERE USED TO DETERMINE DNMT1, DNMT3A, AND DNMT3B MRNA EXPRESSION LEVELS. RESULTS: SIGNIFICANTLY LOWER DNMT1 (P = 0.015543) AND DNMT3A (P = 0.003652) TRANSCRIPT LEVELS IN SLE PATIENTS WERE OBSERVED COMPARED WITH HEALTHY CONTROLS. NEVERTHELESS, THE DNMT3B MRNA EXPRESSION LEVELS WERE MARKEDLY LOWER COMPARED WITH DNMT1 AND DNMT3A, BOTH IN PBMCS FROM AFFECTED PATIENTS AND THOSE FROM CONTROL SUBJECTS. FURTHERMORE, THE DNMT1 TRANSCRIPT LEVELS WERE POSITIVELY CORRELATED WITH SLE DISEASE ACTIVITY INDEX (SLEDAI) (R (S) = 0.4087, P = 0.020224), WHILE THE DNMT3A TRANSCRIPT LEVELS WERE NEGATIVELY CORRELATED WITH PATIENTS AGE (R (S) = -0.3765, P = 0.03369). CONCLUSIONS: OUR ANALYSES CONFIRMED THE IMPORTANCE OF EPIGENETIC ALTERATIONS IN SLE ETIOLOGY. MOREOVER, OUR RESULTS SUGGEST THAT THE PRESENCE OF SOME CLINICAL MANIFESTATIONS, SUCH AS PHOTOTOSENSITIVITY AND ARTHRITIS, MIGHT BE ASSOCIATED WITH THE DYSREGULATION OF DNA METHYLTRANSFERASES' MRNA EXPRESSION LEVELS. 2017 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 1545 37 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 10 1594 36 DNA METHYLATION PROFILING REVEALS DIFFERENCES IN THE 3 HUMAN MONOCYTE SUBSETS AND IDENTIFIES UREMIA TO INDUCE DNA METHYLATION CHANGES DURING DIFFERENTIATION. HUMAN MONOCYTES ARE A HETEROGENEOUS CELL POPULATION CONSISTING OF 3 SUBSETS: CLASSICAL CD14++CD16-, INTERMEDIATE CD14++CD16+ AND NONCLASSICAL CD14+CD16++ MONOCYTES. VIA POORLY CHARACTERIZED MECHANISMS, INTERMEDIATE MONOCYTE COUNTS RISE IN CHRONIC INFLAMMATORY DISEASES, AMONG WHICH CHRONIC KIDNEY DISEASE IS OF PARTICULAR EPIDEMIOLOGIC IMPORTANCE. DNA METHYLATION IS A CENTRAL EPIGENETIC FEATURE THAT CONTROLS HEMATOPOIESIS. BY APPLYING NEXT-GENERATION METHYL-SEQUENCING WE NOW TESTED HOW FAR THE 3 MONOCYTE SUBSETS DIFFER IN THEIR DNA METHYLOME AND WHETHER UREMIA INDUCES DNA METHYLATION CHANGES IN DIFFERENTIATING MONOCYTES. WE FOUND THAT EACH MONOCYTE SUBSET DISPLAYS A UNIQUE PHENOTYPE WITH REGARDS TO DNA METHYLATION. GENES WITH DIFFERENTIALLY METHYLATED PROMOTER REGIONS IN INTERMEDIATE MONOCYTES WERE LINKED TO DISTINCT IMMUNOLOGICAL PROCESSES, WHICH IS IN LINE WITH RESULTS FROM RECENT GENE EXPRESSION ANALYSES. IN VITRO, UREMIA INDUCED DYSREGULATION OF DNA METHYLATION IN DIFFERENTIATING MONOCYTES, WHICH AFFECTED SEVERAL TRANSCRIPTION REGULATORS IMPORTANT FOR MONOCYTE DIFFERENTIATION (E.G., FLT3, HDAC1, MNT) AND LED TO ENHANCED GENERATION OF INTERMEDIATE MONOCYTES. AS POTENTIAL MEDIATOR, THE UREMIC TOXIN AND METHYLATION INHIBITOR S-ADENOSYLHOMOCYSTEINE INDUCED SHIFTS IN MONOCYTE SUBSETS IN VITRO, AND ASSOCIATED WITH MONOCYTE SUBSET COUNTS IN VIVO. OUR DATA SUPPORT THE CONCEPT OF MONOCYTE TRICHOTOMY AND THE DISTINCT ROLE OF INTERMEDIATE MONOCYTES IN HUMAN IMMUNITY. THE SHIFT IN MONOCYTE SUBSETS THAT OCCURS IN CHRONIC KIDNEY DISEASE, A PROINFLAMMATORY CONDITION OF SUBSTANTIAL EPIDEMIOLOGICAL IMPACT, MAY BE INDUCED BY ACCUMULATION OF UREMIC TOXINS THAT MEDIATE EPIGENETIC DYSREGULATION. 2016 11 3044 37 GENOME-WIDE ANALYSIS OF 5-HMC IN THE PERIPHERAL BLOOD OF SYSTEMIC LUPUS ERYTHEMATOSUS PATIENTS USING AN HMEDIP-CHIP. SYSTEMIC LUPUS ERYTHEMATOSUS (SLE) IS A CHRONIC, POTENTIALLY FATAL SYSTEMIC AUTOIMMUNE DISEASE CHARACTERIZED BY THE PRODUCTION OF AUTOANTIBODIES AGAINST A WIDE RANGE OF SELF-ANTIGENS. TO INVESTIGATE THE ROLE OF THE 5-HMC DNA MODIFICATION WITH REGARD TO THE ONSET OF SLE, WE COMPARED THE LEVELS 5-HMC BETWEEN SLE PATIENTS AND NORMAL CONTROLS. WHOLE BLOOD WAS OBTAINED FROM PATIENTS, AND GENOMIC DNA WAS EXTRACTED. USING THE HMEDIP-CHIP ANALYSIS AND VALIDATION BY QUANTITATIVE RT-PCR (RT-QPCR), WE IDENTIFIED THE DIFFERENTIALLY HYDROXYMETHYLATED REGIONS THAT ARE ASSOCIATED WITH SLE. THERE WERE 1,701 GENES WITH SIGNIFICANTLY DIFFERENT 5-HMC LEVELS AT THE PROMOTER REGION IN THE SLE PATIENTS COMPARED WITH THE NORMAL CONTROLS. THE CPG ISLANDS OF 3,826 GENES SHOWED SIGNIFICANTLY DIFFERENT 5-HMC LEVELS IN THE SLE PATIENTS COMPARED WITH THE NORMAL CONTROLS. OUT OF THE DIFFERENTIALLY HYDROXYMETHYLATED GENES, THREE WERE SELECTED FOR VALIDATION, INCLUDING TREX1, CDKN1A AND CDKN1B. THE HYDROXYMETHYLATION LEVELS OF THE THREE GENES WERE CONFIRMED BY RT-QPCR. THE RESULTS SUGGESTED THAT THERE WERE SIGNIFICANT ALTERATIONS OF 5-HMC IN SLE PATIENTS. THUS, THESE DIFFERENTIALLY HYDROXYMETHYLATED GENES MAY CONTRIBUTE TO THE PATHOGENESIS OF SLE. THESE FINDINGS SHOW THE SIGNIFICANCE OF 5-HMC AS A POTENTIAL BIOMARKER OR PROMISING TARGET FOR EPIGENETIC-BASED SLE THERAPIES. 2015 12 3069 40 GENOME-WIDE DNA METHYLATION PROFILING IDENTIFIES EPIGENETIC CHANGES IN CD4+ AND CD14+ CELLS OF MULTIPLE SCLEROSIS PATIENTS. MULTIPLE SCLEROSIS (MS) IS A CHRONIC AUTOIMMUNE AND DEGENERATIVE DISEASE OF THE CENTRAL NERVOUS SYSTEM, WHICH DEVELOPS IN GENETICALLY PREDISPOSED INDIVIDUALS UPON EXPOSURE TO ENVIRONMENTAL INFLUENCES. ENVIRONMENTAL TRIGGERS OF MS, SUCH AS VIRAL INFECTIONS OR SMOKING, WERE DEMONSTRATED TO AFFECT DNA METHYLATION, AND THUS TO INVOLVE THIS IMPORTANT EPIGENETIC MECHANISM IN THE DEVELOPMENT OF PATHOLOGICAL PROCESS. TO IDENTIFY MS-ASSOCIATED DNA METHYLATION HALLMARKS, WE PERFORMED GENOME-WIDE DNA METHYLATION PROFILING OF TWO CELL POPULATIONS (CD4+ T-LYMPHOCYTES AND CD14+ MONOCYTES), COLLECTED FROM THE SAME TREATMENT-NAIVE RELAPSING-REMITTING MS PATIENTS AND HEALTHY SUBJECTS, USING ILLUMINA 450 K METHYLATION ARRAYS. WE REVEALED SIGNIFICANT CHANGES IN DNA METHYLATION FOR BOTH CELL POPULATIONS IN MS. IN CD4+ CELLS OF MS PATIENTS THE MAJORITY OF DIFFERENTIALLY METHYLATED POSITIONS (DMPS) WERE SHOWN TO BE HYPOMETHYLATED, WHILE IN CD14+ CELLS - HYPERMETHYLATED. DIFFERENTIAL METHYLATION OF HLA-DRB1 GENE IN CD4+ AND CD14+ CELLS WAS ASSOCIATED WITH CARRIAGE OF DRB1*15 ALLELE INDEPENDENTLY FROM THE DISEASE STATUS. BESIDES, ABOUT 20% OF IDENTIFIED DMPS WERE SHARED BETWEEN TWO CELL POPULATIONS AND HAD THE SAME DIRECTION OF METHYLATION CHANGES; THEY MAY BE INVOLVED IN BASIC EPIGENETIC PROCESSES OCCURING IN MS. THESE FINDINGS SUGGEST THAT THE EPIGENETIC MECHANISM OF DNA METHYLATION IN IMMUNE CELLS CONTRIBUTES TO MS; FURTHER STUDIES ARE NOW REQUIRED TO VALIDATE THESE RESULTS AND UNDERSTAND THEIR FUNCTIONAL SIGNIFICANCE. 2022 13 1587 33 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 14 6468 24 TISSUE-SPECIFIC ENRICHMENT OF LYMPHOMA RISK LOCI IN REGULATORY ELEMENTS. THOUGH NUMEROUS POLYMORPHISMS HAVE BEEN ASSOCIATED WITH RISK OF DEVELOPING LYMPHOMA, HOW THESE VARIANTS FUNCTION TO PROMOTE TUMORIGENESIS IS POORLY UNDERSTOOD. HERE, WE REPORT THAT LYMPHOMA RISK SNPS, ESPECIALLY IN THE NON-HODGKIN'S LYMPHOMA SUBTYPE CHRONIC LYMPHOCYTIC LEUKEMIA, ARE SIGNIFICANTLY ENRICHED FOR CO-LOCALIZATION WITH EPIGENETIC MARKS OF ACTIVE GENE REGULATION. THESE ENRICHMENTS WERE SEEN IN A LYMPHOID-SPECIFIC MANNER FOR NUMEROUS ENCODE DATASETS, INCLUDING DNASE-HYPERSENSITIVITY AS WELL AS MULTIPLE SEGMENTATION-DEFINED ENHANCER REGIONS. FURTHERMORE, WE IDENTIFY PUTATIVELY FUNCTIONAL SNPS THAT ARE BOTH IN REGULATORY ELEMENTS IN LYMPHOCYTES AND ARE ASSOCIATED WITH GENE EXPRESSION CHANGES IN BLOOD. WE DEVELOPED AN ALGORITHM, UES, THAT USES A MONTE CARLO SIMULATION APPROACH TO CALCULATE THE ENRICHMENT OF PREVIOUSLY IDENTIFIED RISK SNPS IN VARIOUS FUNCTIONAL ELEMENTS. THIS MULTISCALE APPROACH INTEGRATING MULTIPLE DATASETS HELPS DISENTANGLE THE UNDERLYING BIOLOGY OF LYMPHOMA, AND MORE BROADLY, IS GENERALLY APPLICABLE TO GWAS RESULTS FROM OTHER DISEASES AS WELL. 2015 15 3473 34 IDENTIFICATION OF A NOVEL, METHYLATION-DEPENDENT, RUNX2 REGULATORY REGION ASSOCIATED WITH OSTEOARTHRITIS RISK. OSTEOARTHRITIS (OA) IS A COMMON, MULTIFACTORIAL AND POLYGENIC SKELETAL DISEASE THAT, IN ITS SEVEREST FORM, REQUIRES JOINT REPLACEMENT SURGERY TO RESTORE MOBILITY AND TO RELIEVE CHRONIC PAIN. USING TISSUES FROM THE ARTICULATING JOINTS OF 260 PATIENTS WITH OA AND A RANGE OF IN VITRO EXPERIMENTS, INCLUDING CRISPR-CAS9, WE HAVE CHARACTERIZED AN INTERGENIC REGULATORY ELEMENT. HERE, GENOTYPE AT AN OA RISK LOCUS CORRELATES WITH DIFFERENTIAL DNA METHYLATION, WITH ALTERED GENE EXPRESSION OF BOTH A TRANSCRIPTIONAL REGULATOR (RUNX2), AND A CHROMATIN REMODELLING PROTEIN (SUPT3H). RUNX2 IS A STRONG CANDIDATE FOR OA SUSCEPTIBILITY, WITH ITS ENCODED PROTEIN BEING ESSENTIAL FOR SKELETOGENESIS AND HEALTHY JOINT FUNCTION. THE OA RISK LOCUS INCLUDES SINGLE NUCLEOTIDE POLYMORPHISMS (SNPS) LOCATED WITHIN AND FLANKING THE DIFFERENTIALLY METHYLATED REGION (DMR). THE OA ASSOCIATION SNP, RS10948172, DEMONSTRATES PARTICULARLY STRONG CORRELATION WITH METHYLATION, AND TWO INTERGENIC SNPS FALLING WITHIN THE DMR (RS62435998 AND RS62435999) DEMONSTRATE GENETIC AND EPIGENETIC EFFECTS ON THE REGULATORY ACTIVITY OF THIS REGION. WE THEREFORE POSIT THAT THE OA SIGNAL MEDIATES ITS EFFECT BY MODULATING THE METHYLATION OF THE REGULATORY ELEMENT, WHICH THEN IMPACTS ON GENE EXPRESSION, WITH RUNX2 BEING THE PRINCIPAL TARGET. OUR STUDY HIGHLIGHTS THE INTERPLAY BETWEEN DNA METHYLATION, OA GENETIC RISK AND THE DOWNSTREAM REGULATION OF GENES CRITICAL TO NORMAL JOINT FUNCTION. 2018 16 3764 33 INTEGRATIVE ANALYSIS OF DNA METHYLATION AND GENE EXPRESSION DATA IDENTIFIES EPAS1 AS A KEY REGULATOR OF COPD. CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) IS A COMPLEX DISEASE. GENETIC, EPIGENETIC, AND ENVIRONMENTAL FACTORS ARE KNOWN TO CONTRIBUTE TO COPD RISK AND DISEASE PROGRESSION. THEREFORE WE DEVELOPED A SYSTEMATIC APPROACH TO IDENTIFY KEY REGULATORS OF COPD THAT INTEGRATES GENOME-WIDE DNA METHYLATION, GENE EXPRESSION, AND PHENOTYPE DATA IN LUNG TISSUE FROM COPD AND CONTROL SAMPLES. OUR INTEGRATIVE ANALYSIS IDENTIFIED 126 KEY REGULATORS OF COPD. WE IDENTIFIED EPAS1 AS THE ONLY KEY REGULATOR WHOSE DOWNSTREAM GENES SIGNIFICANTLY OVERLAPPED WITH MULTIPLE GENES SETS ASSOCIATED WITH COPD DISEASE SEVERITY. EPAS1 IS DISTINCT IN COMPARISON WITH OTHER KEY REGULATORS IN TERMS OF METHYLATION PROFILE AND DOWNSTREAM TARGET GENES. GENES PREDICTED TO BE REGULATED BY EPAS1 WERE ENRICHED FOR BIOLOGICAL PROCESSES INCLUDING SIGNALING, CELL COMMUNICATIONS, AND SYSTEM DEVELOPMENT. WE CONFIRMED THAT EPAS1 PROTEIN LEVELS ARE LOWER IN HUMAN COPD LUNG TISSUE COMPARED TO NON-DISEASE CONTROLS AND THAT EPAS1 GENE EXPRESSION IS REDUCED IN MICE CHRONICALLY EXPOSED TO CIGARETTE SMOKE. AS EPAS1 DOWNSTREAM GENES WERE SIGNIFICANTLY ENRICHED FOR HYPOXIA RESPONSIVE GENES IN ENDOTHELIAL CELLS, WE TESTED EPAS1 FUNCTION IN HUMAN ENDOTHELIAL CELLS. EPAS1 KNOCKDOWN BY SIRNA IN ENDOTHELIAL CELLS IMPACTED GENES THAT SIGNIFICANTLY OVERLAPPED WITH EPAS1 DOWNSTREAM GENES IN LUNG TISSUE INCLUDING HYPOXIA RESPONSIVE GENES, AND GENES ASSOCIATED WITH EMPHYSEMA SEVERITY. OUR FIRST INTEGRATIVE ANALYSIS OF GENOME-WIDE DNA METHYLATION AND GENE EXPRESSION PROFILES ILLUSTRATES THAT NOT ONLY DOES DNA METHYLATION PLAY A 'CAUSAL' ROLE IN THE MOLECULAR PATHOPHYSIOLOGY OF COPD, BUT IT CAN BE LEVERAGED TO DIRECTLY IDENTIFY NOVEL KEY MEDIATORS OF THIS PATHOPHYSIOLOGY. 2015 17 1567 33 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 1995 34 EPIGENETIC AND GENETIC ALTERATIONS AND THEIR INFLUENCE ON GENE REGULATION IN CHRONIC LYMPHOCYTIC LEUKEMIA. BACKGROUND: TO UNDERSTAND THE CHANGES OF GENE REGULATION IN CARCINOGENESIS, WE EXPLORED SIGNALS OF DNA METHYLATION - A STABLE EPIGENETIC MARK OF GENE REGULATORY ELEMENTS - AND DESIGNED A COMPUTATIONAL MODEL TO PROFILE LOSS AND GAIN OF REGULATORY ELEMENTS (RES) DURING CARCINOGENESIS. WE ALSO UTILIZED SEQUENCING DATA TO ANALYZE THE ALLELE FREQUENCY OF SINGLE NUCLEOTIDE POLYMORPHISMS (SNPS) AND DETECTED THE CANCER-ASSOCIATED SNPS, I.E., THE SNPS DISPLAYING THE SIGNIFICANT ALLELE FREQUENCY DIFFERENCE BETWEEN CANCER AND NORMAL SAMPLES. RESULTS: AFTER APPLYING THIS MODEL TO CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) DATA, WE IDENTIFIED RES DIFFERENTIALLY ACTIVATED (DRES) BETWEEN NORMAL AND CLL CELLS, CONSISTING OF 6,802 DRES GAINED AND 4,606 DRES LOST IN CLL. THE IDENTIFIED REGULATORY PERTURBATIONS COINCIDE WITH CHANGES IN THE EXPRESSION OF TARGET GENES. IN PARTICULAR, THE GENES ENCODING DNA METHYLTRANSFERASES HARBOR MULTIPLE LOST-IN-CANCER DRES AND ZERO GAINED-IN-CANCER DRES, INDICATING THAT THE DAMAGED REGULATION OF THESE GENES MIGHT BE ONE OF THE KEY CAUSES OF TUMOR FORMATION. DRES DISPLAY A SIGNIFICANTLY ELEVATED DENSITY OF THE GENOME-WIDE ASSOCIATION STUDY (GWAS) SNPS ASSOCIATED WITH CLL AND CLL-RELATED TRAITS. WE OBSERVED THAT MOST OF DRE GWAS SNPS ASSOCIATED WITH CLL AND CLL-RELATED TRAITS (83%) DISPLAY A SIGNIFICANT HAPLOTYPE ASSOCIATION AMONG THE IDENTIFIED CANCER-ASSOCIATED ALLELES AND THE RISK ALLELES THAT HAVE BEEN REPORTED IN GWAS. ALSO DRES ARE ENRICHED FOR THE BINDING SITES OF THE WELL-ESTABLISHED B-CELL AND CLL TRANSCRIPTION FACTORS (TFS) NF-KB, AP2, P53, E2F1, PAX5, AND SP1. WE ALSO IDENTIFIED CLL-ASSOCIATED SNPS AND DEMONSTRATED THAT THE MUTATIONS AT THESE SNPS CHANGE THE BINDING SITES OF KEY TFS MUCH MORE FREQUENTLY THAN EXPECTED. CONCLUSIONS: THROUGH EXPLORING SEQUENCING DATA MEASURING DNA METHYLATION, WE IDENTIFIED THE EPIGENETIC ALTERATIONS (MORE SPECIFICALLY, DNA METHYLATION) AND GENETIC MUTATIONS ALONG NON-CODING GENOMIC REGIONS CLL, AND DEMONSTRATED THAT THESE CHANGES PLAY A CRITICAL ROLE IN CARCINOGENESIS THROUGH DAMAGING THE REGULATION OF KEY GENES AND ALTERNATING THE BINDING OF KEY TFS IN B AND CLL CELLS. 2017 19 51 32 A DISTINCT EPIGENETIC PROFILE DISTINGUISHES STENOTIC FROM NON-INFLAMED FIBROBLASTS IN THE ILEAL MUCOSA OF CROHN'S DISEASE PATIENTS. BACKGROUND: THE CHRONIC REMITTING AND RELAPSING INTESTINAL INFLAMMATION CHARACTERISTIC OF CROHN'S DISEASE FREQUENTLY LEADS TO FIBROSIS AND SUBSEQUENT STENOSIS OF THE INFLAMED REGION. APPROXIMATELY A THIRD OF ALL CROHN'S DISEASE PATIENTS REQUIRE RESECTION AT SOME STAGE IN THEIR DISEASE COURSE. AS THE PATHOGENESIS OF CROHN'S DISEASE ASSOCIATED FIBROSIS IS LARGELY UNKNOWN, A STRONG NECESSITY EXISTS TO BETTER UNDERSTAND THE PATHOPHYSIOLOGY THEREOF. METHODS: IN THIS STUDY, WE INVESTIGATED CHANGES OF THE DNA METHYLOME AND TRANSCRIPTOME OF ILEUM-DERIVED FIBROBLASTS ASSOCIATED TO THE OCCURRENCE OF CROHN'S DISEASE ASSOCIATED FIBROSIS. EIGHTEEN SAMPLES WERE INCLUDED IN A DNA METHYLATION ARRAY AND TWENTY-ONE SAMPLES WERE USED FOR RNA SEQUENCING. RESULTS: MOST DIFFERENTIALLY METHYLATED REGIONS AND DIFFERENTIALLY EXPRESSED GENES WERE OBSERVED WHEN COMPARING STENOTIC WITH NON-INFLAMED SAMPLES. BY CONTRAST, FEW DIFFERENCES WERE OBSERVED WHEN COMPARING CROHN'S DISEASE WITH NON-CROHN'S DISEASE, OR INFLAMED WITH NON-INFLAMED TISSUE. INTEGRATIVE METHYLATION AND GENE EXPRESSION ANALYSES REVEALED DYSREGULATION OF GENES ASSOCIATED TO THE PRKACA AND E2F1 NETWORK, WHICH IS INVOLVED IN CELL CYCLE PROGRESSION, ANGIOGENESIS, EPITHELIAL TO MESENCHYMAL TRANSITION, AND BILE METABOLISM. CONCLUSION: OUR RESEARCH PROVIDES EVIDENCE THAT THE METHYLOME AND THE TRANSCRIPTOME ARE SYSTEMATICALLY DYSREGULATED IN STENOSIS-ASSOCIATED FIBROBLASTS. 2018 20 3455 39 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