1 2766 132 EXPRESSION, POLYMORPHISM AND METHYLATION PATTERN OF INTERLEUKIN-6 IN PERIODONTAL TISSUES. PERIODONTITIS IS CONSIDERED AN INFLAMMATORY DISORDER OF BACTERIAL ETIOLOGY THAT RESULTS IN PERIODONTAL TISSUE DESTRUCTION, AS A RESULT OF COMPLEX INTERACTIONS BETWEEN PERIODONTAL PATHOGENS, HOST AND IMMUNE RESPONSE. GENETIC AND EPIGENETIC MECHANISMS MAY MODULATE THE INDIVIDUAL RESPONSE SINCE IT IS ABLE TO INFLUENCE THE GENE EXPRESSION. THE AIM OF THIS STUDY WAS TO EVALUATE THE IMPACT OF -174 G/C POLYMORPHISM AND THE METHYLATION STATUS OF THE PROMOTER REGION OF IL-6 GENE ON THE EXPRESSION OF IL-6 IN GINGIVAL SAMPLES FROM INDIVIDUALS WITH CHRONIC PERIODONTITIS. GINGIVAL BIOPSIES WERE COLLECTED FROM 21 PATIENTS WITH CHRONIC PERIODONTITIS AND 21 CONTROLS. HISTOLOGIC SECTIONS STAINED BY HEMATOXYLIN-EOSIN WERE USED FOR HISTOPATHOLOGICAL EVALUATION. THE IL-6 GENE EXPRESSION WAS ASSESSED BY QUANTITATIVE REAL-TIME PCR. THE POLYMORPHISM IL-6 -174 C/G WAS STUDIED BY POLYMERASE CHAIN REACTION (PCR) AMPLIFICATION AND RESTRICTION ENDONUCLEASE DIGESTION (HSPII). METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION WAS USED TO VERIFY THE DNA METHYLATION PATTERN. THE NUMBER OF INFLAMMATORY CELLS IN TISSUE FRAGMENTS FROM INDIVIDUALS WITH CHRONIC PERIODONTITIS WAS HIGHER THAN IN THE CONTROL GROUP AND THE INFLAMMATORY INFILTRATE WAS PREDOMINANTLY MONONUCLEAR. THE EXPRESSION OF IL-6 WAS HIGHER IN THE GROUP WITH PERIODONTITIS. IN POLYMORPHISM ASSAY, NO STATISTICAL DIFFERENCE IN THE DISTRIBUTION OF GENOTYPES AND ALLELES IN BOTH GROUPS WERE OBSERVED. THE MOST OF SAMPLES WERE PARTIALLY METHYLATED. NO DIFFERENCE WAS OBSERVED IN METHYLATION PATTERN FROM TWO DIFFERENT REGIONS OF THE IL-6 GENE AMONG GROUPS. THE HIGH EXPRESSION OF IL-6 IS AN IMPORTANT FACTOR RELATED TO CHRONIC PERIODONTITIS, BUT WAS NOT ASSOCIATED WITH METHYLATION STATUS OR THE -174 (G/C) GENETIC POLYMORPHISM, SUGGESTING THAT OTHER MECHANISMS ARE INVOLVED IN THIS GENE TRANSCRIPTION REGULATION. 2013 2 3440 52 HYPERMETHYLATION AND LOW TRANSCRIPTION OF TLR2 GENE IN CHRONIC PERIODONTITIS. PERIODONTITIS IS AN INFLAMMATORY DISORDER CHARACTERIZED BY INTERACTIONS BETWEEN PERIODONTAL PATHOGENS AND HOST'S IMMUNE RESPONSE. EPIGENETIC MAY CONTRIBUTE TO DISEASE DEVELOPMENT AND OUTCOME BY INFLUENCING THE EXPRESSION OF GENES INVOLVED IN THE IMMUNE RESPONSE. IT HAS BEEN SHOWN THAT TOLL-LIKE RECEPTORS (TLR) PLAY AN IMPORTANT ROLE IN THE RESPONSE TO PERIODONTOPATHIC BACTERIA. THE AIM OF STUDY WAS TO EVALUATE THE METHYLATION STATUS AND THE EXPRESSION OF TLR2 GENE IN GINGIVAL SAMPLES FROM INDIVIDUALS WITH AND WITHOUT PERIODONTITIS. DNA WAS ANALYZED USING THE METHYL PROFILER DNA METHYLATION QPCR ASSAY. DNA METHYLATION AND TRANSCRIPT LEVELS WERE EVALUATED BY REAL-TIME POLYMERASE CHAIN REACTION. THE PERIODONTITIS GROUP SHOWED A HYPERMETHYLATED PROFILE AND A LOW EXPRESSION OF GENE. POSITIVE CORRELATION BETWEEN THE TLR2 METHYLATION FREQUENCY AND PROBING DEPTH WAS OBSERVED. THIS STUDY GIVES THE FIRST EVIDENCE OF METHYLATION FREQUENCY IN INFLAMED PERIODONTAL TISSUES AND OF THE POSSIBLE PARTICIPATION OF METHYLATION IN THE DEVELOPMENT OF PERIODONTITIS. 2013 3 1805 40 EFFECT OF SMOKING ON THE DNA METHYLATION PATTERN OF THE SOCS1 PROMOTER IN EPITHELIAL CELLS FROM THE SALIVA OF PATIENTS WITH CHRONIC PERIODONTITIS. BACKGROUND: THE AIM OF THE PRESENT STUDY WAS TO EVALUATE THE METHYLATION PATTERN IN THE SUPPRESSOR OF CYTOKINE SIGNALING 1 (SOCS1) GENE IN SMOKERS AND NON-SMOKERS WITH CHRONIC PERIODONTITIS (CP). METHODS: METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION (PCR) WAS PERFORMED TO DETERMINE THE METHYLATION STATUS OF THE SOCS1 PROMOTER IN 45 SALIVA SAMPLES FROM SMOKERS AND NON-SMOKERS WITH CP. RESULTS: CELLS FROM THE SALIVA OF CP PATIENTS WHO SMOKED WERE 7.08 TIMES MORE LIKELY TO HAVE A METHYLATED SOCS1 PROMOTER THAN CELLS FROM THE SALIVA OF NON-SMOKING PATIENTS. CONCLUSIONS: SOCS1 GENE PROMOTER METHYLATION, WITH ITS POTENTIAL EFFECTS ON THE EXPRESSION OF THIS GENE, SEEMS TO BE A CONSEQUENCE OF EXPOSURE TO TOBACCO AND NOT TO PERIODONTAL DISEASE. FURTHER STUDIES ARE NEEDED TO ELUCIDATE THE RELATIONSHIP BETWEEN THE EPIGENETIC CONTROL OF IMMUNE RESPONSE GENE EXPRESSION, EXPOSURE TO ENVIRONMENTAL FACTORS, AND THE DEVELOPMENT, PROGRESSION, AND PROGNOSIS OF CP. 2019 4 2762 49 EXPRESSION OF TET2 ENZYME INDICATES ENHANCED EPIGENETIC MODIFICATION OF CELLS IN PERIODONTITIS. DNA METHYLATION IS AN IMPORTANT EPIGENETIC MECHANISM INVOLVED IN THE REGULATION OF GENE EXPRESSION, AND A REDUCTION IN DNA METHYLATION INFLUENCES CELL-CYCLE PROGRESSION AND CELL DIFFERENTIATION IN INFLAMMATORY CELLS. THE AIM OF THE PRESENT STUDY WAS TO ANALYZE THE DNA-METHYLATION PATTERN AT LOCAL AND GLOBAL/SYSTEMIC LEVELS IN PATIENTS WITH PERIODONTITIS AND GINGIVITIS. TWENTY-ONE SUBJECTS WITH GENERALIZED, SEVERE PERIODONTITIS AND 17 SUBJECTS WITH GINGIVAL INFLAMMATION BUT NO ATTACHMENT LOSS WERE RECRUITED. GINGIVAL BIOPSIES AND PERIPHERAL BLOOD SAMPLES WERE COLLECTED AND PREPARED FOR IMMUNOHISTOCHEMICAL ANALYSIS OF 5-METHYLCYTOSINE (5MC), 5-HYDROXYMETHYLCYTOSINE (5HMC), TEN-ELEVEN TRANSLOCATION 2 (TET2), AND DNA METHYLTRANSFERASE 1 (DNMT1). WHILST A SIMILAR PATTERN FOR 5MC AND 5HMC DNA METHYLATION WAS FOUND IN BOTH TYPES OF LESIONS, A SIGNIFICANTLY LARGER PROPORTION OF TET2-POSITIVE CELLS WAS FOUND IN PERIODONTITIS LESIONS THAN IN GINGIVITIS LESIONS. QUANTITATIVE REAL-TIME PCR ANALYSIS SHOWED NO DIFFERENCES BETWEEN GINGIVITIS AND PERIODONTITIS LESIONS REGARDING EXPRESSION OF TET2 AND ISOCITRATE DEHYDROGENASE (IDH) GENES, WHILE THE GLOBAL LEVEL OF 5HMC WAS SIGNIFICANTLY HIGHER IN BLOOD THAN IN TISSUE IN PATIENTS WITH PERIODONTITIS. IT IS SUGGESTED THAT EPIGENETIC CHANGES ARE MORE COMMON IN PERIODONTITIS LESIONS THAN IN GINGIVITIS LESIONS AND THAT SUCH CHANGES ARE TISSUE SPECIFIC. 2016 5 1500 48 DNA METHYLATION ANALYSIS OF CD4+ T CELLS IN PATIENTS WITH PSORIASIS. PSORIASIS IS A CHRONIC INFLAMMATORY SKIN DISEASE THAT IS CHARACTERIZED BY ABERRANT CROSS-TALK BETWEEN KERATINOCYTES AND IMMUNE CELLS SUCH AS CD4+ T CELLS, RESULTING IN KERATINOCYTE HYPERPROLIFERATION IN THE EPIDERMIS. DNA METHYLATION, ONE OF SEVERAL EPIGENETIC MECHANISMS, PLAYS AN IMPORTANT ROLE IN GENE EXPRESSION WITHOUT CHANGING THE DNA SEQUENCE. SEVERAL STUDIES HAVE SUGGESTED THE INVOLVEMENT OF EPIGENETIC REGULATION IN SKIN LESIONS FROM PATIENTS WITH PSORIASIS. IN THIS STUDY, WE INVESTIGATED THE GENOME-WIDE DNA METHYLATION STATUS OF CD4+ T CELLS IN PATIENTS WITH PSORIASIS COMPARED WITH HEALTHY SUBJECTS USING METHYLATED DNA IMMUNOPRECIPITATION SEQUENCING (MEDIP-SEQ). THE RESULTS OF MEDIP-SEQ SHOWED THAT THE GLOBAL METHYLATION VALUES OF CD4+ T CELLS ARE HIGHER IN PATIENTS WITH PSORIASIS THAN IN HEALTHY CONTROLS, PARTICULARLY IN THE PROMOTER REGIONS. AMONG THE MOST HYPERMETHYLATED GENES IN THE PROMOTER REGIONS, WE SELECTED THE GENES WHOSE EXPRESSION IS SIGNIFICANTLY REDUCED IN THE CD4+ T CELLS OF PSORIASIS PATIENTS. STUDIES USING THE METHYLATION INHIBITOR 5-AZACYTIDINE IN VITRO METHYLATION ASSAYS HAVE SHOWN THAT THE DIFFERENTIAL EXPRESSION LEVELS WERE ASSOCIATED WITH THE METHYLATION STATUS OF EACH GENE. BISULFITE SEQUENCING OF THE TRANSCRIPTION START REGION OF PHOSPHATIDIC ACID PHOSPHATASE TYPE 2 DOMAIN CONTAINING 3 (PPAPDC3), ONE OF THE SELECTED GENES, SHOWED HYPERMETHYLATION IN THE CD4+ T CELLS OF PSORIASIS PATIENTS. THESE RESULTS SUGGESTED THAT THE METHYLATION STATUS, WHICH IS IDENTIFIED BY MEDIP-SEQ OF THE GENES, WAS CORRELATED WITH THE MRNA EXPRESSION LEVEL OF THE GENES. COLLECTIVELY, THE DNA METHYLATION STATUS IN CD4+ T CELLS MIGHT BE ASSOCIATED WITH THE PATHOGENESIS OF PSORIASIS. 2014 6 2019 44 EPIGENETIC CHANGE IN E-CADHERIN AND COX-2 TO PREDICT CHRONIC PERIODONTITIS. BACKGROUND: DNA METHYLATION OF CERTAIN GENES FREQUENTLY OCCURS IN NEOPLASTIC CELLS. ALTHOUGH THE CAUSE REMAINS UNKNOWN, MANY GENES HAVE BEEN IDENTIFIED WITH SUCH ATYPICAL METHYLATION IN NEOPLASTIC CELLS. THE HYPERMETHYLATION OF E-CADHERIN AND CYCLOOXYGENASE 2 (COX-2) IN CHRONIC INFLAMMATION SUCH AS CHRONIC PERIODONTITIS MAY DEMONSTRATE MILD LESION/MUTATION EPIGENETIC LEVEL. THIS STUDY COMPARES THE HYPERMETHYLATION STATUS OF E-CADHERIN AND COX-2 GENES WHICH ARE OFTEN FOUND IN BREAST CANCER PATIENTS WITH THAT IN CHRONIC PERIODONTITIS. METHODS: TOTAL DNA WAS EXTRACTED FROM THE BLOOD SAMPLES OF 108 SYSTEMICALLY HEALTHY NON-PERIODONTITIS SUBJECTS, AND THE GINGIVAL TISSUES AND BLOOD SAMPLES OF 110 CHRONIC PERIODONTITIS PATIENT AS WELL AS NEOPLASTIC TISSUES OF 106 BREAST CANCER PATIENTS. METHYLATION-SPECIFIC PCR FOR E-CADHERIN AND COX-2 WAS PERFORMED ON THESE SAMPLES AND THE PCR PRODUCTS WERE ANALYZED ON 2% AGAROSE GEL. RESULTS: HYPERMETHYLATION OF E-CADHERIN AND COX-2 WAS OBSERVED IN 38% AND 35% OF THE BREAST CANCER SAMPLES, RESPECTIVELY. IN CHRONIC PERIODONTITIS PATIENTS THE DETECTION RATE WAS 25% AND 19% RESPECTIVELY, AND NONE WAS FOUND IN THE SYSTEMICALLY HEALTHY NON-PERIODONTITIS CONTROL SUBJECTS. THE HYPERMETHYLATION STATUS WAS SHOWN TO BE CORRELATED AMONG THE THREE GROUPS WITH STATISTICAL SIGNIFICANCE (P < 0.0001). THE METHYLATION OF CPG ISLANDS IN E-CADHERIN AND COX-2 GENES IN PERIODONTITIS PATIENTS OCCURS MORE FREQUENTLY IN PERIODONTITIS PATIENTS THAN IN THE CONTROL SUBJECTS, BUT OCCURS LESS FREQUENTLY THAN IN THE BREAST CANCER PATIENTS. CONCLUSIONS: THIS SET OF DATA SHOWS THAT THE EPIGENETIC CHANGE IN E-CADHERIN AND CYCLOOXYGENASE-2 IS ASSOCIATED WITH CHRONIC PERIODONTITIS. THE EPIGENETIC CHANGES PRESENTED IN CHRONIC INFLAMMATION PATIENTS MIGHT DEMONSTRATE AN IRREVERSIBLE DESTRUCTION IN THE TISSUES OR ORGANS SIMILAR TO THE EFFECTS OF CANCER. CHRONIC PERIODONTITIS TO SOME EXTENT MIGHT BE ASSOCIATED WITH DNA HYPERMETHYLATION WHICH IS RELATED TO CANCER RISK FACTORS. 2010 7 2400 36 EPIGENETIC REPROGRAMMING OF IMMUNE CELLS IN WOMEN WITH PCOS IMPACT GENES CONTROLLING REPRODUCTIVE FUNCTION. CONTEXT: POLYCYSTIC OVARY SYNDROME (PCOS) IS A CHRONIC DISEASE AFFECTING REPRODUCTIVE FUNCTION AND WHOLE-BODY METABOLISM. ALTHOUGH THE ETIOLOGY IS UNCLEAR, EMERGING EVIDENCE INDICATES THAT THE EPIGENETICS MAY BE A CONTRIBUTING FACTOR. OBJECTIVE: TO DETERMINE THE ROLE OF GLOBAL AND GENOME-WIDE EPIGENETIC MODIFICATIONS IN SPECIFIC IMMUNE CELLS IN PCOS COMPARED WITH CONTROLS AND WHETHER THESE COULD BE RELATED TO CLINICAL FEATURES OF PCOS. DESIGN: CROSS-SECTIONAL STUDY. PARTICIPANTS: WOMEN WITH (N = 17) OR WITHOUT PCOS (N = 17). SETTING: RECRUITED FROM THE GENERAL COMMUNITY. MAIN OUTCOME MEASURES: ISOLATED PERIPHERAL BLOOD MONONUCLEAR CELLS WERE ANALYZED USING MULTICOLOR FLOW CYTOMETRY METHODS TO DETERMINE GLOBAL DNA METHYLATION LEVELS IN A CELL-SPECIFIC FASHION. TRANSCRIPTOMIC AND GENOME-WIDE DNA METHYLATION ANALYSES WERE PERFORMED ON T HELPER CELLS USING RNA SEQUENCING AND REDUCED REPRESENTATION BISULFITE SEQUENCING. RESULTS: WOMEN WITH PCOS HAD LOWER GLOBAL DNA METHYLATION IN MONOCYTES (P = 0.006) AND IN T HELPER (P = 0.004), T CYTOTOXIC (P = 0.004), AND B CELLS (P = 0.03). SPECIFIC GENOME-WIDE DNA METHYLATION ANALYSIS OF T HELPER CELLS FROM WOMEN WITH PCOS IDENTIFIED 5581 DIFFERENTIALLY METHYLATED CPG SITES. FUNCTIONAL GENE ONTOLOGY ENRICHMENT ANALYSIS SHOWED THAT GENES LOCATED AT THE PROXIMITY OF DIFFERENTIALLY METHYLATED CPG SITES BELONG TO PATHWAYS RELATED TO REPRODUCTIVE FUNCTION AND IMMUNE CELL FUNCTION. HOWEVER, THESE GENES WERE NOT ALTERED AT THE TRANSCRIPTOMIC LEVEL. CONCLUSIONS: IT WAS SHOWN THAT PCOS IS ASSOCIATED WITH GLOBAL AND GENE-SPECIFIC DNA METHYLATION REMODELING IN A CELL TYPE-SPECIFIC MANNER. FURTHER INVESTIGATION IS WARRANTED TO DETERMINE WHETHER EPIGENETIC REPROGRAMMING OF IMMUNE CELLS IS IMPORTANT IN DETERMINING THE DIFFERENT PHENOTYPES OF PCOS. 2019 8 6311 34 THE RELATION BETWEEN DNA METHYLATION PATTERNS AND SERUM CYTOKINE LEVELS IN COMMUNITY-DWELLING ADULTS: A PRELIMINARY STUDY. BACKGROUND: THE LEVELS OF CIRCULATING CYTOKINES FLUCTUATE WITH AGE, ACUTE ILLNESS, AND CHRONIC DISEASE, AND ARE PREDICTIVE OF MORTALITY; THIS IS ALSO TRUE FOR PATTERNS OF DNA (CPG) METHYLATION. GIVEN THAT IMMUNE CELLS ARE PARTICULARLY SENSITIVE TO CHANGES IN THE CONCENTRATION OF CYTOKINES IN THEIR MICROENVIRONMENT, WE HYPOTHESIZED THAT SERUM LEVELS OF TNF, IL-6, IL-8 AND IL-10 WOULD CORRELATE WITH GENOME-WIDE ALTERATIONS IN THE DNA METHYLATION LEVELS OF BLOOD LEUKOCYTES. TO TEST THIS, WE EVALUATED COMMUNITY-DWELLING ADULTS (N = 14; 48-78 YEARS OLD) RECRUITED TO A PILOT STUDY FOR THE CANADIAN LONGITUDINAL STUDY ON AGING (CLSA), EXAMINING DNA METHYLATION PATTERNS IN PERIPHERAL BLOOD MONONUCLEAR CELLS USING THE ILLUMINA HUMANMETHYLATION 450 K BEADCHIP. RESULTS: WE SHOW THAT, APART FROM AGE, SERUM IL-10 LEVELS EXHIBITED THE MOST SUBSTANTIAL ASSOCIATION TO DNA METHYLATION PATTERNS, FOLLOWED BY TNF, IL-6 AND IL-8. FURTHERMORE, WHILE THE LEVELS OF THESE CYTOKINES WERE HIGHER IN ELDERLY ADULTS, NO ASSOCIATIONS WITH EPIGENETIC ACCELERATED AGING, DERIVED USING THE EPIGENETIC CLOCK, WERE OBSERVED. CONCLUSIONS: AS A PRELIMINARY STUDY WITH A SMALL SAMPLE SIZE, THE CONCLUSIONS DRAWN FROM THIS WORK MUST BE VIEWED WITH CAUTION; HOWEVER, OUR OBSERVATIONS ARE ENCOURAGING AND CERTAINLY WARRANT MORE SUITABLY POWERED STUDIES OF THIS RELATIONSHIP. 2017 9 344 45 ALTERED BDNF METHYLATION IN PATIENTS WITH CHRONIC MUSCULOSKELETAL PAIN AND HIGH BIOPSYCHOSOCIAL COMPLEXITY. PURPOSE: THE INTERMED INSTRUMENT, WHICH WAS DEVELOPED TO MEASURE PATIENT'S BIOPSYCHOSOCIAL (BPS) COMPLEXITY, REPRESENTS A POWERFUL DIAGNOSTIC AND THERAPEUTIC TOOL. EPIGENETIC CHANGES ARE THE INTERFACE BETWEEN SIGNALS FROM THE ENVIRONMENT AND GENETIC MODIFICATIONS, AFFECTING GENE EXPRESSION, IN PARTICULAR, BY DNA METHYLATION OF CPG DINUCLEOTIDES IN PROMOTOR REGIONS OF THE CORRESPONDING GENES. THE BRAIN-DERIVED NEUROTROPHIC FACTOR (BDNF) GENE PLAYS A CRUCIAL ROLE IN THE CENTRAL SENSITIZATION (CS) OF PAIN. IN THIS STUDY, WE HYPOTHESIZED THAT CHRONIC PAIN MODIFIES THE METHYLATION LEVELS OF THE BDNF GENE IN A MANNER THAT IS INTERCONNECTED WITH THE BPS STATUS. PATIENTS AND METHODS: FIFTY-EIGHT CHRONIC MUSCULOSKELETAL PAIN PATIENTS (CMSP) WERE ENROLLED IN THE STUDY. DNA WAS EXTRACTED FROM BLOOD SAMPLES, THE METHYLATION LEVELS OF 13 CPG SITES IN THE BDNF PROMOTER WERE MEASURED BY PYROSEQUENCING, AND ASSOCIATION STUDIES WITH VARIOUS PATIENT PARAMETERS AND THE INTERMED SCORES WERE PERFORMED. RESULTS: INTERESTINGLY, A NEGATIVE CORRELATION (-0.40) WAS FOUND BETWEEN THE TOTAL INTERMED SCORES AND THE AVERAGE CPG METHYLATION VALUES OF THE BDNF GENE, BUT NO CORRELATION WAS OBSERVED WITH THE SEVERITY OF PAIN, DEGREE OF ANXIETY, DEPRESSION, OR KINESIOPHOBIA AND CATASTROPHISM. MOREOVER, THE ASSOCIATION WAS INDEPENDENT OF AGE, SEX AND LEVEL OF COMORBIDITIES. CONCLUSION: THIS RESULT SHOWS THAT CMSP, IN ASSOCIATION WITH ITS BIOPSYCHOSOCIAL CONTEXT, EPIGENETICALLY DECREASES THE DEGREE OF METHYLATION OF THE BDNF PROMOTER AND SHOULD THEREFORE INCREASE THE LEVEL OF BDNF TRANSCRIPTION. IT ALSO SUGGESTS A ROLE OF THE INTERMED TOOL TO DETECT A RELATIONSHIP BETWEEN THE BPS COMPLEXITY AND THE EPIGENETIC CONTROL OF A TARGET GENE. THE POSSIBLE UPREGULATION OF BDNF EXPRESSION MIGHT BE, AT LEAST IN PART, THE SIGNAL FOR CHRONIC PAIN-INDUCED CENTRAL SENSITIZATION (CS). THIS COULD PARTLY EXPLAIN WHY PATIENTS WITH A HIGHER LEVEL OF COMPLEXITY FEEL MORE PAIN THAN THOSE WITH LOWER COMPLEXITY. 2020 10 287 32 AGING AND CHRONIC SUN EXPOSURE CAUSE DISTINCT EPIGENETIC CHANGES IN HUMAN SKIN. EPIGENETIC CHANGES ARE WIDELY CONSIDERED TO PLAY AN IMPORTANT ROLE IN AGING, BUT EXPERIMENTAL EVIDENCE TO SUPPORT THIS HYPOTHESIS HAS BEEN SCARCE. WE HAVE USED ARRAY-BASED ANALYSIS TO DETERMINE GENOME-SCALE DNA METHYLATION PATTERNS FROM HUMAN SKIN SAMPLES AND TO INVESTIGATE THE EFFECTS OF AGING, CHRONIC SUN EXPOSURE, AND TISSUE VARIATION. OUR RESULTS REVEAL A HIGH DEGREE OF TISSUE SPECIFICITY IN THE METHYLATION PATTERNS AND ALSO SHOWED VERY LITTLE INTERINDIVIDUAL VARIATION WITHIN TISSUES. DATA STRATIFICATION BY AGE REVEALED THAT DNA FROM OLDER INDIVIDUALS WAS CHARACTERIZED BY A SPECIFIC HYPERMETHYLATION PATTERN AFFECTING LESS THAN 1% OF THE MARKERS ANALYZED. INTERESTINGLY, STRATIFICATION BY SUN EXPOSURE PRODUCED A FUNDAMENTALLY DIFFERENT PATTERN WITH A SIGNIFICANT TREND TOWARDS HYPOMETHYLATION. OUR RESULTS THUS IDENTIFY DEFINED AGE-RELATED DNA METHYLATION CHANGES AND SUGGEST THAT THESE ALTERATIONS MIGHT CONTRIBUTE TO THE PHENOTYPIC CHANGES ASSOCIATED WITH SKIN AGING. 2010 11 2771 39 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 12 6589 41 TUMOR NECROSIS FACTOR-ALPHA GENE PROMOTER METHYLATION IN JAPANESE ADULTS WITH CHRONIC PERIODONTITIS AND RHEUMATOID ARTHRITIS. BACKGROUND AND OBJECTIVE: OVER-EXPRESSION OF TUMOR NECROSIS FACTOR-ALPHA (TNF-ALPHA) PLAYS A PATHOLOGICAL ROLE IN CHRONIC PERIODONTITIS (CP) AND RHEUMATOID ARTHRITIS (RA), WHICH MIGHT BE REGULATED BY THE EPIGENETIC MECHANISM. THE AIM OF THE PRESENT STUDY WAS TO EVALUATE WHETHER THERE IS A UNIQUE METHYLATION PROFILE OF THE TNF-ALPHA GENE PROMOTER IN BLOOD CELLS OF INDIVIDUALS WITH CP AND RA. MATERIAL AND METHODS: THE STUDY PARTICIPANTS CONSISTED OF 30 JAPANESE ADULTS WITH RA (RA GROUP), 30 RACE-MATCHED ADULTS WITH CP ONLY (CP GROUP) AND 30 RACE-MATCHED HEALTHY CONTROLS (H GROUP). GENOMIC DNA ISOLATED FROM PERIPHERAL BLOOD WAS MODIFIED BY SODIUM BISULFITE AND ANALYZED, BY DIRECT SEQUENCING, TO INVESTIGATE DNA METHYLATION OF THE TNF-ALPHA GENE PROMOTER REGION. THE LEVEL OF TNF-ALPHA PRODUCED IN MONONUCLEAR CELLS STIMULATED WITH PORPHYROMONAS GINGIVALIS LIPOPOLYSACCHARIDE WAS DETERMINED USING ELISA. RESULTS: TWELVE CYTOSINE-GUANINE DINUCLEOTIDE (CPG) MOTIFS WERE IDENTIFIED IN THE TNF-ALPHA PROMOTER FRAGMENT FROM -343 TO +57 BP. THE CP GROUP SHOWED A SIGNIFICANTLY HIGHER METHYLATION RATE AND FREQUENCY AT -72 BP THAN THE H GROUP (P < 0.01). THE RA GROUP EXHIBITED SIGNIFICANTLY HIGHER METHYLATION RATES AT SEVEN CPG MOTIFS (-302, -163, -119, -72, -49, -38 AND +10 BP), AND SIGNIFICANTLY HIGHER METHYLATION FREQUENCIES AT SIX CPG MOTIFS (-163, -119, -72, -49, -38 AND +10 BP), THAN THE H GROUP (P < 0.01 FOR ALL COMPARISONS). THE LEVELS OF TNF-ALPHA PRODUCED WERE SIGNIFICANTLY DIFFERENT BETWEEN INDIVIDUALS WITH AND WITHOUT METHYLATION AT -163 BP (P = 0.03). CONCLUSION: THESE RESULTS SUGGEST THAT THE HYPERMETHYLATED STATUS OF CPG MOTIFS IN THE TNF-ALPHA GENE PROMOTER IN BLOOD CELLS MAY BE UNIQUE TO JAPANESE ADULTS WITH CP AND RA. 2016 13 1589 40 DNA METHYLATION PROFILING IN A CIGARETTE SMOKE-EXPOSED MOUSE MODEL OF AIRWAY INFLAMMATION. PURPOSE: DNA METHYLATION, A MAJOR EPIGENETIC MODIFICATION, HAS BEEN DOCUMENTED TO PLAY AN IMPORTANT ROLE IN CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD). IN THIS STUDY, WE AIMED TO PROFILE THE DNA METHYLATION PATTERNS IN A MOUSE MODEL OF AIRWAY INFLAMMATION INDUCED BY CIGARETTE SMOKE (CS), A FOREMOST RISK FACTOR OF COPD. MATERIAL AND METHODS: TO ESTABLISH A MODEL OF AIRWAY INFLAMMATION, WILD-TYPE MICE WERE EXPOSED TO MAINSTREAM CS OR ROOM AIR FOR 2 HOURS TWICE DAILY, 6 DAYS PER WEEK FOR CONSECUTIVE 4 WEEKS. LUNG TISSUES OF THE MICE WERE COLLECTED FOR GENOME-WIDE DNA METHYLATION ANALYSIS BY LIQUID HYBRIDIZATION CAPTURE-BASED BISULFITE SEQUENCING, WHICH WERE USED FOR INTERSECTION ANALYSIS WITH GENE EXPRESSION BY CDNA MICROARRAY TO IDENTIFY CANDIDATE METHYLATED GENES. THEN, FUNCTIONAL ENRICHMENT ANALYSES WITH PROTEIN-PROTEIN INTERACTION (PPI) NETWORK REGARDING THESE GENES WERE CONDUCTED TO EXPLORE THE POTENTIAL MECHANISMS. RESULTS: AFTER 4-WEEK CS EXPOSURE, THE LEVEL OF DNA METHYLATION ACCOMPANIED BY A SUBACUTE AIRWAY INFLAMMATION WAS MARKEDLY ENHANCED, AND 2002 DIFFERENTIALLY METHYLATED GENES (DMGS) WERE ANNOTATED, INCLUDING 565 DMGS CONTAINED METHYLATIONS IN GENE PROMOTERS, WHICH WERE USED FOR INTERSECTION WITH THE DIFFERENTIALLY EXPRESSED GENES. THEN, 135 CANDIDATE METHYLATED GENES WERE FURTHER SELECTED BY THE INTERSECTION, AMONG WHICH 58 GENES WITH FUNCTIONAL METHYLATED MODIFICATION WERE FINALLY IDENTIFIED. FURTHER ANALYSES REVEALED CANDIDATE METHYLATED GENES WERE SIGNIFICANTLY ENRICHED IN A COMPLICATED NETWORK OF SIGNALS AND PROCESSES, INCLUDING INTERLEUKINS, TOLL-LIKE RECEPTORS, T-CELLS DIFFERENTIATION, OXIDATIVE STRESS, MAST CELLS ACTIVATION, STEM CELLS PROLIFERATION, ETC., AS WELL AS THE 58 FUNCTIONAL METHYLATED GENES WERE PARTIALLY LOCATED AT KEY POSITIONS IN PPI NETWORK, ESPECIALLY CXCL1, DDX58 AND JAK3. CONCLUSION: THIS STUDY SUGGESTS CS EXPOSURE SIGNIFICANTLY ENHANCES DNA METHYLATED LEVEL, AND THE POTENTIAL FUNCTIONAL METHYLATED GENES ARE CLOSELY RELATED TO COMPLICATED INFLAMMATORY-IMMUNE RESPONSES, WHICH MAY PROVIDE SOME NEW EXPERIMENTAL EVIDENCE IN UNDERSTANDING THE EPIGENETIC MECHANISMS OF CS-INDUCED AIRWAY INFLAMMATION IN COPD. 2022 14 507 41 ASSOCIATION OF INCREASED DNA METHYLTRANSFERASE EXPRESSION WITH CARCINOGENESIS AND POOR PROGNOSIS IN PANCREATIC DUCTAL ADENOCARCINOMA. INTRODUCTION: EPIGENETIC MODIFICATIONS PLAY AN IMPORTANT ROLE IN MULTISTAGE CARCINOGENESIS. THE ROLE OF THE THREE FUNCTIONAL DNA METHYLTRANSFERASES (DNMTS) IN PANCREATIC CARCINOGENESIS HAS NOT BEEN FULLY UNDERSTOOD. THE MAIN GOAL OF THIS STUDY WAS TO EXAMINE DNMT EXPRESSION IN DIFFERENT STAGES OF PANCREATIC DUCTAL ADENOCARCINOMA (PDAC), AND EVALUATE THEIR PROGNOSTIC SIGNIFICANCE IN PDAC. MATERIALS AND METHODS: A LARGE NUMBER OF PREMALIGNANT AND MALIGNANT PANCREATIC LESIONS WERE OBTAINED BY MANUAL MICRODISSECTION. QUANTITATIVE REAL-TIME RT-PCR WAS USED TO DETECT DNMTS MRNA EXPRESSION. NONPARAMETRIC TEST, LOGRANK TEST AND COX REGRESSION ANALYSIS WERE USED TO EVALUATE THE CLINICAL SIGNIFICANCE OF DNMT EXPRESSION. RESULTS: THE MRNA EXPRESSION OF THE THREE DNMTS INCREASED WITH THE DEVELOPMENT OF PANCREATIC CANCER FROM NORMAL DUCT TO PANCREATIC INTRADUCTAL NEOPLASIA AND FURTHER TO PDAC, AND WERE STATISTICALLY CORRELATED WITH EACH OTHER. EXPRESSION OF THE THREE DNMTS WAS STATISTICALLY CORRELATED WITH TNM STAGING AND HISTORY OF CHRONIC PANCREATITIS. DNMT3A AND DNMT3B, BUT NOT DNMT1 EXPRESSION, WAS STATISTICALLY CORRELATED WITH TUMOUR SIZE. PATIENTS WITH HIGHER LEVELS OF DNMT1, DNMT3A AND/OR DNMT3B EXPRESSION HAD AN OVERALL LOWER SURVIVAL THAN THOSE WITH LOWER LEVELS OF EXPRESSION. UNIVARIATE ANALYSIS SHOWED THAT HIGH EXPRESSION LEVELS OF DNMTS, ALCOHOL CONSUMPTION, TUMOUR DIFFERENTIATION AND TNM STAGING WERE STATISTICALLY SIGNIFICANT RISK FACTORS. MULTIVARIATE ANALYSIS SHOWED THAT HIGH LEVEL OF DNMT3B EXPRESSION AND TUMOUR DIFFERENTIATION WERE STATISTICALLY SIGNIFICANT INDEPENDENT POOR PROGNOSTIC FACTORS. CONCLUSIONS: THESE RESULTS SUGGESTED THAT PANCREATIC CARCINOGENESIS INVOLVES AN INCREASED MRNA EXPRESSION OF THREE DNMTS, AND THEY MAY BECOME VALUABLE DIAGNOSTIC AND PROGNOSTIC MARKERS AS WELL AS POTENTIAL THERAPEUTIC TARGETS FOR PANCREATIC CANCER. 2012 15 3796 40 INTERLEUKIN-6 PROMOTES TUMORIGENESIS BY ALTERING DNA METHYLATION IN ORAL CANCER CELLS. WORLDWIDE ORAL SQUAMOUS CELL CARCINOMA (OSCC) ACCOUNTS FOR MORE THAN 100,000 DEATHS EACH YEAR. CHRONIC INFLAMMATION CONSTITUTES ONE OF THE KEY RISK FACTORS FOR OSCC. ACCUMULATING EVIDENCE SUGGESTS THAT ABERRANT DNA METHYLATION MAY CONTRIBUTE TO OSCC TUMORIGENESIS. THIS STUDY INVESTIGATED WHETHER CHRONIC INFLAMMATION ALTERS DNA METHYLATION AND EXPRESSION OF CANCER-ASSOCIATED GENES IN OSCC. WE ESTABLISHED AN IN VITRO MODEL OF INTERLEUKIN (IL)-6 MEDIATING CHRONIC INFLAMMATION IN OSCC CELL LINES. THEREAFTER, WE MEASURED THE ABILITY OF IL-6 TO INDUCE GLOBAL HYPOMETHYLATION OF LONG INTERSPERSED NUCLEAR ELEMENT-1 (LINE-1) SEQUENCES, AS WELL AS CPG METHYLATION CHANGES USING MULTIPLE METHODOLOGIES INCLUDING QUANTITATIVE PYROSEQUENCING, METHYLATION-SPECIFIC MULTIPLEX LIGATION-DEPENDENT PROBE AMPLIFICATION AND SENSITIVE MELTING ANALYSIS AFTER REAL-TIME-METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION (PCR). GENE EXPRESSION WAS INVESTIGATED BY QUANTITATIVE REVERSE TRANSCRIPTASE-PCR. IL-6 INDUCED SIGNIFICANT GLOBAL LINE-1 HYPOMETHYLATION (P=0.016) IN OUR IN VITRO MODEL OF INFLAMMATORY STRESS IN OSCC CELL LINES. SIMULTANEOUSLY, IL-6 INDUCED CPG PROMOTER METHYLATION CHANGES IN SEVERAL IMPORTANT PUTATIVE TUMOR SUPPRESSOR GENES INCLUDING CHFR, GATA5 AND PAX6. METHYLATION CHANGES CORRELATED INVERSELY WITH THE CHANGES IN THE EXPRESSION OF CORRESPONDING GENES. OUR RESULTS INDICATE THAT IL-6-INDUCED INFLAMMATION PROMOTES TUMORIGENESIS IN THE ORAL CAVITY BY ALTERING GLOBAL LINE-1 HYPOMETHYLATION. IN ADDITION, CONCURRENT HYPERMETHYLATION OF MULTIPLE TUMOR SUPPRESSOR GENES BY IL-6 SUGGESTS THAT EPIGENETIC GENE SILENCING MAY BE AN IMPORTANT CONSEQUENCE OF CHRONIC INFLAMMATION IN THE ORAL CAVITY. THESE FINDINGS HAVE CLINICAL RELEVANCE, AS BOTH METHYLATION AND INFLAMMATION ARE SUITABLE TARGETS FOR DEVELOPING NOVEL PREVENTIVE AND THERAPEUTIC MEASURES. 2011 16 3387 28 HOMOCYSTEINE ASSOCIATED GENOMIC DNA HYPERMETHYLATION IN PATIENTS WITH CHRONIC ALCOHOLISM. HIGHER PLASMA HOMOCYSTEINE CONCENTRATIONS CAN INFLUENCE GENOMIC DNA METHYLATION IN PERIPHERAL BLOOD CELLS. IN THE PRESENT CONTROLLED STUDY WE OBSERVED A SIGNIFICANT INCREASE (10%) OF GENOMIC DNA METHYLATION IN PATIENTS WITH ALCOHOLISM (T = -3.16, DF = 158, P = 0.002) WHICH WAS SIGNIFICANTLY ASSOCIATED WITH THEIR ELEVATED HOMOCYSTEINE LEVELS (MULTIPLE LINEAR REGRESSION, P < 0.001). SINCE METHYLATION OF DNA IS AN IMPORTANT EPIGENETIC FACTOR IN REGULATION OF GENE EXPRESSION THESE FINDINGS MAY HAVE IMPORTANT IMPLICATIONS FOR A POSSIBLE SUBSEQUENT DERANGEMENT OF EPIGENETIC CONTROL THESE PATIENTS. 2004 17 353 40 ALTERED LEVELS OF IMMUNE-REGULATORY MICRORNAS IN PLASMA SAMPLES OF PATIENTS WITH LUPUS NEPHRITIS. INTRODUCTION: LUPUS NEPHRITIS (LN) IS A MAJOR CAUSE OF MORTALITY AND MORBIDITY IN THE PATIENTS WITH LUPUS, A CHRONIC AUTOIMMUNE DISEASE. THE ROLE OF GENETIC AND EPIGENETIC FACTORS IS EMPHASIZED IN THE PATHOGENESIS OF LN. THE AIM OF THE PRESENT STUDY WAS TO EVALUATE THE LEVELS OF IMMUNE-REGULATORY MICRORNAS (E.G., MIR-31, MIR-125A, MIR-142-3P, MIR-146A, AND MIR-155) IN PLASMA SAMPLES OF PATIENTS WITH LN. METHODS: IN THIS STUDY, 26 PATIENTS WITH LN AND 26 HEALTHY INDIVIDUALS WERE INCLUDED. THE PLASMA LEVELS OF THE MICRORNAS WERE EVALUATED BY A QUANTITATIVE REAL-TIME PCR. MOREOVER, THE CORRELATION OF CIRCULATING PLASMA MICRORNAS WITH DISEASE ACTIVITY AND PATHOLOGICAL FINDINGS ALONG WITH THEIR ABILITY TO DISTINGUISH PATIENTS WITH LN WERE ASSESSED. RESULTS: PLASMA LEVELS OF MIR-125A (P = 0.048), MIR-146A (P = 0.005), AND MIR-155 (P< 0.001) WERE SIGNIFICANTLY HIGHER IN COMPARISON BETWEEN THE CASES AND CONTROLS. THE PLASMA LEVEL OF MIR-146A SIGNIFICANTLY CORRELATED WITH THE LEVEL OF ANTI-DOUBLE STRAND-DNA ANTIBODY AND PROTEINURIA. MOREOVER, THERE WAS A SIGNIFICANT CORRELATION BETWEEN MIR-142-3P LEVELS AND DISEASE CHRONICITY AND ACTIVITY INDEX (P <0.05). THE MULTIVARIATE ROC CURVE ANALYSIS INDICATED THE PLASMA CIRCULATING MIR-125A, MIR-142-3P, MIR-146, AND MIR-155 TOGETHER COULD DISCRIMINATE MOST OF THE PATIENTS WITH LN FROM CONTROLS WITH AREA AN UNDER CURVE (AUC) OF 0.89 [95% CI, 0.80-0.98, P<0.001], 88% SENSITIVITY, AND 78% SPECIFICITY. CONCLUSION: BASED ON THE FINDINGS OF THE PRESENT STUDY, THE STUDIED MICRORNAS MAY BE INVOLVED IN THE PATHOGENESIS AND DEVELOPMENT OF LN AND HAVE THE POTENTIAL TO BE USED AS DIAGNOSTIC AND THERAPEUTIC MARKERS IN LN. 2018 18 2281 40 EPIGENETIC REGULATION IN EARLY CHILDHOOD: A MINIATURIZED AND VALIDATED METHOD TO ASSESS HISTONE ACETYLATION. INTRODUCTION: CHRONIC INFLAMMATORY DISEASES INCLUDING ALLERGIES AND ASTHMA ARE THE RESULT OF COMPLEX INTERACTIONS BETWEEN GENES AND ENVIRONMENTAL FACTORS. EPIGENETIC MECHANISMS COMPRISE A SET OF BIOCHEMICAL REACTIONS THAT REGULATE GENE EXPRESSION. IN ORDER TO UNDERSTAND THE CAUSE-EFFECT RELATIONSHIP BETWEEN ENVIRONMENTAL EXPOSURES AND DISEASE DEVELOPMENT, METHODS CAPABLE OF ASSESSING EPIGENETIC REGULATION (ALSO) IN LARGE COHORTS ARE NEEDED. METHODS: FOR THIS PURPOSE, WE DEVELOPED AND EVALUATED A MINIATURIZED CHROMATIN IMMUNOPRECIPITATION (CHIP) ASSAY ALLOWING FOR A COST-EFFECTIVE ASSESSMENT OF HISTONE ACETYLATION OF CANDIDATE GENES IN A QUANTITATIVE FASHION. THIS METHOD WAS THEN APPLIED TO ASSESS H3 AND H4 HISTONE ACETYLATION CHANGES IN CORD BLOOD (CB) SAMPLES FROM AN ESTABLISHED COHORT OF AUSTRALIAN CHILDREN EXPOSED IN THE FETAL PERIOD TO EITHER VERY LOW OR VERY HIGH LEVELS OF MATERNAL FOLATE. RESULTS: OUR CHIP ASSAY WAS VALIDATED FOR A MINIMUM REQUIREMENT OF 1 X 105 TARGET CELLS (E.G. CD4+ T CELLS). VERY HIGH LEVELS OF MATERNAL FOLATE WERE SIGNIFICANTLY ASSOCIATED WITH INCREASED H3/H4 ACETYLATION AT GATA3 AND/OR IL9 PROMOTER REGIONS IN CD4+ T CELLS IN CB. CONCLUSION: WE DEVELOPED A CHIP METHOD ALLOWING RELIABLE ASSESSMENT OF H3/H4 ACETYLATION USING 1 X 105 CELLS ONLY. PRACTICAL APPLICATION OF THIS ASSAY DEMONSTRATED AN ASSOCIATION BETWEEN HIGH MATERNAL FOLATE EXPOSURE AND INCREASED HISTONE ACETYLATION, CORRESPONDING TO A MORE TRANSCRIPTIONALLY PERMISSIVE CHROMATIN STATUS IN THE PROMOTER REGIONS OF SOME TH2-RELATED GENES. 2015 19 1967 43 EPIGENETIC ALTERATION OF THE DOPAMINE TRANSPORTER GENE IN ALCOHOL-DEPENDENT PATIENTS IS ASSOCIATED WITH AGE. CHRONIC ALCOHOL ABUSE AND DEPENDENCE ARE ASSOCIATED WITH DYSFUNCTIONAL DOPAMINERGIC NEUROTRANSMISSION IN MESOCORTICOLIMBIC CIRCUITS. GENETIC AND ENVIRONMENTAL FACTORS HAVE BEEN SHOWN TO MODULATE SUSCEPTIBILITY TO ALCOHOL DEPENDENCE, AND BOTH MAY ACT THROUGH EPIGENETIC MECHANISMS THAT CAN MODULATE GENE EXPRESSION, E.G. DNA METHYLATION AT CPG SITES. RECENT STUDIES HAVE SUGGESTED THAT DNA METHYLATION PATTERNS MAY CHANGE OVER TIME. HOWEVER, FEW DATA ARE AVAILABLE CONCERNING THE RATE OF THESE CHANGES IN SPECIFIC GENES. A RECENT STUDY FOUND THAT HYPERMETHYLATION OF THE PROMOTER OF THE DOPAMINE TRANSPORTER (DAT) GENE WAS POSITIVELY CORRELATED WITH ALCOHOL DEPENDENCE AND NEGATIVELY CORRELATED WITH ALCOHOL CRAVING. THE AIM OF THE PRESENT STUDY WAS TO REPLICATE THESE FINDINGS IN A LARGER SAMPLE OF ALCOHOL-DEPENDENT PATIENTS AND POPULATION-BASED CONTROLS MATCHED FOR AGE AND SEX. NO DIFFERENCE IN METHYLATION LEVEL WAS OBSERVED BETWEEN PATIENTS AND CONTROLS, AND NO DIFFERENCE IN METHYLATION LEVEL WAS OBSERVED BEFORE AND AFTER ALCOHOL WITHDRAWAL IN PATIENTS. HOWEVER, PATIENTS WITH MORE SEVERE CRAVING SHOWED A TREND TOWARDS LOWER DAT METHYLATION LEVELS (P = 0.07), WHICH IS CONSISTENT WITH PREVIOUS FINDINGS. FURTHERMORE, IN OUR OVERALL SAMPLE, DAT METHYLATION LEVELS INCREASED WITH AGE. INTERESTINGLY, A SEPARATE ANALYSIS OF PATIENTS SUGGESTED THAT THIS FINDING WAS MAINLY DRIVEN BY THE PATIENT GROUP. ALTHOUGH THE PRESENT DATA DO NOT CLARIFY WHETHER CHRONIC ALCOHOL ABUSE IS RESPONSIBLE FOR THIS PHENOMENON OR MERELY ENHANCES AN AGEING-SPECIFIC PROCESS, OUR FINDINGS SUGGEST THAT HYPERMETHYLATION IN ALCOHOL-DEPENDENT PATIENTS IS A CONSEQUENCE, RATHER THAN A CAUSE, OF THE DISORDER. 2014 20 3588 52 IMPACT OF TP53 GENE PROMOTER METHYLATION ON CHRONIC LYMPHOCYTIC LEUKEMIA PATHOGENESIS AND PROGRESSION. BACKGROUND: CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) IS A MALIGNANT LYMPHOID DISORDER THAT RESULTS FROM THE OVERGROWTH OF MATURE-LOOKING LYMPHOID CELLS IN THE BLOOD AND LYMPHATIC TISSUE. VARIOUS CLINICAL PRESENTATIONS HAVE BEEN ATTRIBUTED TO THE DISEASE AS A RESULT OF THE DIFFERENT UNDERLYING GENETIC AND EPIGENETIC ALTERATIONS. THE CURRENT STUDY HAS BEEN INITIATED TO STUDY THE ROLE OF AN EPIGENETIC ALTERATION AFFECTING THE PROMOTER OF THE TP53GENE ON CLL PATHOGENESIS AND PROGRESSION. METHODS: THE CURRENT STUDY INVOLVED 54 NEWLY DIAGNOSED PATIENTS PRESENTING WITH CLL AS WELL AS 30 NORMAL INDIVIDUALS AS CONTROLS. AFTER OBTAINING VERBAL CONSENT, DATA COLLECTION WAS DONE AND THE BLOOD COLLECTED FROM ALL ENROLLED INDIVIDUALS FOR HEMATOLOGICAL INVESTIGATIONS AS WELL AS FOR MOLECULAR CATEGORIZATION OF TP53 METHYLATION STATUS. METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION (MS-PCR) TECHNIQUE WAS USED TO DEFINE THE METHYLATION STATUS OF THE TP53 GENE PROMOTER THAT ENCOMPASSES DNA EXTRACTION, BISULFITE CONVERSION, CONVENTIONAL PCR AMPLIFICATION, RUNNING ON AGAROSE GEL AND DOCUMENTATION. FINALLY, STATISTICAL ANALYSIS WAS DONE TO ASSESS ANY CORRELATION OF THE TP53 EPIGENETIC ALTERATION TO THE DISEASE ETIOLOGY AND THE PROGRESSION. RESULTS: IN THE CURRENT STUDY, ALL CONTROLS AND 42 OF 54 PATIENTS SHOW UNMETHYLATED TP53 GENE PROMOTER; ON THE OTHER HAND, THE METHYLATED PROMOTER WAS DETECTED AMONG 12 PATIENTS WITH A P-VALUE OF 0.001. TP53 GENE PROMOTER METHYLATION SIGNIFICANTLY LINKED TO REDUCED PLATELET COUNT (P-VALUE OF 0.047) AND ADVANCED STAGE AT PRESENTATION (P-VALUE OF 0.076). NO SIGNIFICANT DIFFERENCES WERE SEEN AMONG BOTH METHYLATED AND UNMETHYLATED TP53 PROMOTERS IN RELATION TO THE AGE OF THE AFFECTED INDIVIDUALS, TOTAL WHITE BLOOD CELL COUNTS AND HEMOGLOBIN LEVEL OF THE AFFECTED INDIVIDUALS. CONCLUSION: THE CURRENT STUDY REVEALED A SIGNIFICANT CORRELATION OF TP53 GENE PROMOTER METHYLATION TO CHRONIC LYMPHOCYTIC LEUKEMIA PATHOGENESIS AND LOWER PLATELET COUNTS. 2019