1 6589 129 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 2 2766 41 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 3 1805 32 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 2374 55 EPIGENETIC REGULATION OF TNFA EXPRESSION IN PERIODONTAL DISEASE. BACKGROUND: TUMOR NECROSIS FACTOR-ALPHA (TNF-ALPHA) PLAYS A CENTRAL ROLE IN THE MOLECULAR PATHOGENESIS OF PERIODONTAL DISEASE. HOWEVER, THE EPIGENETIC REGULATION ATTRIBUTABLE TO MICROBIAL AND INFLAMMATORY SIGNALS AT THE BIOFILM-GINGIVAL INTERFACE ARE POORLY UNDERSTOOD. IN THIS STUDY, THE DNA METHYLATION ALTERATION WITHIN THE TNFA PROMOTER IN HUMAN GINGIVAL BIOPSIES FROM DIFFERENT STAGES OF PERIODONTAL DISEASE IS INVESTIGATED AND THE REGULATORY MECHANISM OF TNFA TRANSCRIPTION BY DNA METHYLATION IS EXPLORED. METHODS: GINGIVAL BIOPSIES WERE OBTAINED FROM 17 PATIENTS WITH CHRONIC PERIODONTITIS (CP) AND 18 PERIODONTALLY HEALTHY INDIVIDUALS. ANOTHER 11 INDIVIDUALS PARTICIPATED IN AN EXPERIMENTALLY INDUCED GINGIVITIS STUDY, AND GINGIVAL BIOPSIES WERE COLLECTED AT THE BASELINE, INDUCTION, AND RESOLUTION PHASE. TO CONFIRM THAT TNFA PROMOTER METHYLATION MODULATED TNFA TRANSCRIPTION, THP.1 CELLS WERE TREATED WITH A DNA METHYLTRANSFERASE INHIBITOR, 5-AZA-2-DEOXYCYTIDINE (5-AZA-2DC), AND AN RAW294.7 CELL LINE TRANSFECTED WITH A TNFA PROMOTER-SPECIFIC LUCIFERASE REPORTER SYSTEM WITH OR WITHOUT METHYLATION WAS USED. RESULTS: IN GINGIVAL BIOPSIES FROM INDIVIDUALS WITH SEVERE CP, TWO INDIVIDUAL CYTOSINE-GUANINE DINUCLEOTIDES (CPG SITES) WITHIN THE TNFA PROMOTER (AT -163 AND -161 BP) DISPLAYED INCREASED METHYLATION IN CP SAMPLES COMPARED TO THOSE WITH GINGIVAL HEALTH (16.1% +/- 5.1% VERSUS 11.0% +/- 4.6%, P = 0.02 AND 19.8% +/- 4.1% VERSUS 15.4% +/- 3.6%, P = 0.04, RESPECTIVELY). THE METHYLATION LEVEL AT -163 BP WAS INVERSELY ASSOCIATED WITH THE TRANSCRIPTION LEVEL OF TNFA (P = 0.018). HOWEVER, NO SIGNIFICANT DIFFERENCE IN THE TNFA PROMOTER METHYLATION PATTERN WAS OBSERVED IN SAMPLES BIOPSIED DURING THE INDUCTION OR RESOLUTION PHASE OF EXPERIMENTALLY INDUCED GINGIVITIS, WHICH REPRESENTED A REVERSIBLE PERIODONTAL LESION. THP.1 CELLS TREATED WITH 5-AZA-2DC DEMONSTRATED A TIME-DEPENDENT INCREASE IN TNFA MESSENGER LEVEL. IT WAS ALSO FOUND THAT THE LUCIFERASE ACTIVITY DECREASED 2.6-FOLD IN A CONSTRUCT CONTAINING AN IN VITRO METHYLATED TNFA PROMOTER WHEN COMPARED TO THE UNMETHYLATED INSERT (P = 0.03). CONCLUSION: ALTHOUGH THE BIOPSY SAMPLES REPRESENTED A MIXED CELL POPULATION, THE CHANGE IN PROMOTER METHYLATION STATUS IN CHRONIC PERIODONTAL DISEASE SUGGESTED THAT DNA METHYLATION MAY BE AN IMPORTANT REGULATORY MECHANISM IN CONTROLLING TNFA TRANSCRIPTIONAL EXPRESSION IN PERIODONTAL DISEASE. 2013 5 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 6 3783 43 INTERFERON-GAMMA PROMOTER HYPOMETHYLATION AND INCREASED EXPRESSION IN CHRONIC PERIODONTITIS. AIM: THE GOAL OF THIS INVESTIGATION WAS TO DETERMINE WHETHER EPIGENETIC MODIFICATIONS IN THE IFNG PROMOTER ARE ASSOCIATED WITH AN INCREASE OF IFNG TRANSCRIPTION IN DIFFERENT STAGES OF PERIODONTAL DISEASES. MATERIALS AND METHODS: DNA WAS EXTRACTED FROM GINGIVAL BIOPSY SAMPLES COLLECTED FROM 47 TOTAL SITES FROM 47 DIFFERENT SUBJECTS: 23 PERIODONTALLY HEALTHY SITES, 12 EXPERIMENTALLY INDUCED GINGIVITIS SITES AND 12 CHRONIC PERIODONTITIS SITES. LEVELS OF DNA METHYLATION WITHIN THE IFNG PROMOTER CONTAINING SIX CPG DINUCLEOTIDES WERE DETERMINED USING PYROSEQUENCING TECHNOLOGY. INTERFERON GAMMA MRNA EXPRESSION WAS ANALYSED BY QUANTITATIVE POLYMERASE CHAIN REACTIONS USING ISOLATED RNA FROM PART OF THE BIOLOGICAL SAMPLES MENTIONED ABOVE. RESULTS: THE METHYLATION LEVEL OF ALL SIX ANALYSED CPG SITES WITHIN THE IFNG PROMOTER REGION IN THE PERIODONTITIS BIOPSIES 52% [INTERQUARTILE RANGE, IQR (43.8%, 63%)] WAS SIGNIFICANTLY LOWER THAN PERIODONTALLY HEALTHY SAMPLES 62% [IQR (51.3%, 74%)], P=0.007 AND GINGIVITIS BIOPSIES 63% [IQR (55%, 74%)], P=0.02. THE TRANSCRIPTIONAL LEVEL OF IFNG IN PERIODONTITIS BIOPSIES WAS 1.96-FOLD AND SIGNIFICANTLY HIGHER THAN TISSUES WITH PERIODONTAL HEALTH (P=0.04). ALTHOUGH THE MRNA LEVEL FROM EXPERIMENTAL GINGIVITIS SAMPLES EXHIBITED AN 8.5-FOLD INCREASE AS COMPARED WITH PERIODONTALLY HEALTHY SAMPLES, NO SIGNIFICANT METHYLATION DIFFERENCE WAS OBSERVED IN EXPERIMENTAL GINGIVITIS SAMPLE. CONCLUSIONS: A HYPOMETHYLATION PROFILE WITHIN IFNG PROMOTER REGION IS RELATED TO AN INCREASE OF IFNG TRANSCRIPTION PRESENT IN THE CHRONIC PERIODONTITIS BIOPSIES, WHILE SUCH AN INCREASE OF IFNG IN EXPERIMENTALLY INDUCED GINGIVITIS SEEMS INDEPENDENT OF PROMOTER METHYLATION ALTERATION. 2010 7 3588 38 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 8 353 36 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 9 2762 35 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 10 2847 26 FREQUENT P15 PROMOTER METHYLATION IN TUMOR AND PERIPHERAL BLOOD FROM HEPATOCELLULAR CARCINOMA PATIENTS. WE PROSPECTIVELY ANALYZED P15 METHYLATION PATTERNS IN 25 SURGICALLY RESECTED TUMORS AND 130 PLASMA, SERUM, AND BUFFY COAT SAMPLES FROM HEPATOCELLULAR CARCINOMA (HCC) PATIENTS, CONTROLS WITH CHRONIC HEPATITIS/CIRRHOSIS, AND HEALTHY SUBJECTS. USING METHYLATION-SPECIFIC PCR, WE DEMONSTRATED FOR THE FIRST TIME P15 PROMOTER METHYLATION IN 64% OF TUMORS AND 25% (4 OF 16) OF PATIENTS' PLASMA AND SERUM SAMPLES. CONCURRENT P15 AND P16 METHYLATION WAS SHOWN IN 48% OF TUMORS, AND P15/P16 METHYLATION WAS DETECTED IN THE PLASMA/SERUM OF 92% (11 OF 12) OF PATIENTS. OF NOTE, 75% OF 12 PATIENTS WITH CONCURRENT TUMOR METHYLATION DEVELOPED CLINICAL METASTASIS/RECURRENCE (P = 0.027). IN BUFFY COAT SAMPLES, P15 METHYLATION WAS DETECTED IN ALL EIGHT PATIENTS WITH TUMOR P15 METHYLATION, SUGGESTING THE PRESENCE OF CIRCULATING TUMOR CELLS. NONE OF THE CONTROL SAMPLES WERE METHYLATION POSITIVE. OUR DATA UNDERSCORE THE IMPORTANT ROLE(S) OF P15 AND P16 METHYLATION IN HEPATOCARCINOGENESIS AND TUMOR PROGRESSION. AMONG 92% (23 OF 25) OF PATIENTS WITH TUMOR P15/P16 METHYLATION, CIRCULATING TUMOR DNA AND HCC CELLS WERE DETECTED IN THE PERIPHERAL BLOOD OF 87% (20 OF 23) OF PATIENTS. THE COMBINATION OF THESE EPIGENETIC MARKERS MAY PROVE VALUABLE FOR NONINVASIVE HCC DIAGNOSIS AND DISEASE MONITORING. 2000 11 2400 50 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 12 6311 35 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 13 3387 29 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 14 507 31 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 3440 38 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 16 2633 42 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 17 1497 33 DNA METHYLATION AGE IS ACCELERATED IN ALCOHOL DEPENDENCE. ALCOHOL DEPENDENCE (ALC) IS A CHRONIC, RELAPSING DISORDER THAT INCREASES THE BURDEN OF CHRONIC DISEASE AND SIGNIFICANTLY CONTRIBUTES TO NUMEROUS PREMATURE DEATHS EACH YEAR. PREVIOUS RESEARCH SUGGESTS THAT CHRONIC, HEAVY ALCOHOL CONSUMPTION IS ASSOCIATED WITH DIFFERENTIAL DNA METHYLATION PATTERNS. IN ADDITION, DNA METHYLATION LEVELS AT CERTAIN CPG SITES HAVE BEEN CORRELATED WITH AGE. WE USED AN EPIGENETIC CLOCK TO INVESTIGATE THE POTENTIAL ROLE OF EXCESSIVE ALCOHOL CONSUMPTION IN EPIGENETIC AGING. WE EXPLORED THIS QUESTION IN FIVE INDEPENDENT COHORTS, INCLUDING DNA METHYLATION DATA DERIVED FROM DATASETS FROM BLOOD (N = 129, N = 329), LIVER (N = 92, N = 49), AND POSTMORTEM PREFRONTAL CORTEX (N = 46). ONE BLOOD DATASET AND ONE LIVER TISSUE DATASET OF INDIVIDUALS WITH ALC EXHIBITED POSITIVE AGE ACCELERATION (P < 0.0001 AND P = 0.0069, RESPECTIVELY), WHEREAS THE OTHER BLOOD AND LIVER TISSUE DATASETS BOTH EXHIBITED TRENDS OF POSITIVE AGE ACCELERATION THAT WERE NOT SIGNIFICANT (P = 0.83 AND P = 0.57, RESPECTIVELY). PREFRONTAL CORTEX TISSUE EXHIBITED A TREND OF NEGATIVE AGE ACCELERATION (P = 0.19). THESE RESULTS SUGGEST THAT EXCESSIVE ALCOHOL CONSUMPTION MAY BE ASSOCIATED WITH EPIGENETIC AGING IN A TISSUE-SPECIFIC MANNER AND WARRANTS FURTHER INVESTIGATION USING MULTIPLE TISSUE SAMPLES FROM THE SAME INDIVIDUALS. 2018 18 2759 41 EXPRESSION OF IL-17 AND ITS GENE PROMOTER METHYLATION STATUS ARE ASSOCIATED WITH THE PROGRESSION OF CHRONIC HEPATITIS B VIRUS INFECTION. TO EXPLORE INTERLEUKIN-17 (IL-17) AND ITS EPIGENETIC REGULATION DURING THE PROGRESSION OF CHRONIC HEPATITIS B VIRUS (HBV) INFECTION.A TOTAL OF 162 PATIENTS WITH CHRONIC HBV INFECTION, INCLUDING 75 WITH CHRONIC HEPATITIS B (CHB), 54 WITH HEPATITIS B-ASSOCIATED LIVER CIRRHOSIS AND 33 WITH HEPATITIS B-ASSOCIATED HEPATOCELLULAR CARCINOMA (HBV-HCC), WERE ENROLLED IN THIS STUDY. THIRTY HEALTHY ADULTS OF THE SAME ETHNICITY WERE ENROLLED IN THE CONTROL GROUP. WHOLE VENOUS BLOOD WAS OBTAINED FROM THE PATIENTS AND NORMAL CONTROLS (N = 30). CLINICAL AND LABORATORY PARAMETERS WERE ASSESSED, AND WE PERFORMED ENZYME-LINKED IMMUNOSORBENT ASSAY AND QUANTITATIVE REAL-TIME PCR TO MEASURE THE SERUM LEVELS AND RELATIVE MRNA EXPRESSION OF IL-17, RESPECTIVELY. IL-17 PROMOTER METHYLATION IN PERIPHERAL BLOOD MONONUCLEAR CELLS WAS ASSESSED BY METHYLATION-SPECIFIC PCR. WE ANALYZED THE SERUM AND MRNA LEVELS OF IL-17 AND IL-17 PROMOTER METHYLATION IN THE 4 GROUPS AS WELL AS THE EFFECT OF METHYLATION ON SERUM IL-17 LEVELS. CORRELATIONS BETWEEN THE IL-17 PROMOTER METHYLATION STATUS AND CLINICAL PARAMETERS WERE ANALYZED BY SPEARMAN CORRELATION ANALYSIS.COMPARED TO THE NORMAL CONTROL GROUP, THE PATIENT GROUPS EXHIBITED SIGNIFICANTLY HIGHER SERUM AND RELATIVE MRNA LEVELS OF IL-17. THE METHYLATION DISTRIBUTION AMONG THE PATIENTS WAS SIGNIFICANTLY LOWER THAN THAT AMONG THE NORMAL CONTROLS (P < .05), WITH THE HBV-HCC GROUP SHOWING THE LOWEST IL-17 GENE METHYLATION FREQUENCY. THE AVERAGE IL-17 PROMOTER CG METHYLATION LEVEL WAS NEGATIVELY CORRELATED WITH IL-17 MRNA EXPRESSION (R = -0.39, P = .03), AND NEGATIVE CORRELATIONS BETWEEN IL-17 PROMOTER METHYLATION AND PROTHROMBIN TIME ACTIVITY (R = -0.585, P = .035), ALANINE AMINOTRANSFERASE (R = -0.522, P < .01), ASPARTATE AMINOTRANSFERASE (R = -0.315, P < .05), AND THE MODEL FOR END-STAGE LIVER DISEASE SCORE (R = -0.461, P < .05) WERE OBSERVED. IL-17 SERUM LEVELS IN THE METHYLATED-PROMOTER GROUPS WERE SIGNIFICANTLY LOWER THAN THOSE IN THE UNMETHYLATED-PROMOTER GROUPS.IL-17 EXPRESSION AND PROMOTER METHYLATION WERE ASSOCIATED WITH CHRONIC HBV INFECTION PROGRESSION, ESPECIALLY IN THE HBV-HCC GROUP. THE IL-17 PROMOTER STATUS MAY HELP CLINICIANS INITIATE THE CORRECT TREATMENT STRATEGY AT THE CHB STAGE. 2019 19 1500 49 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 20 2079 32 EPIGENETIC DNA METHYLATION CHANGES ASSOCIATED WITH HEADACHE CHRONIFICATION: A RETROSPECTIVE CASE-CONTROL STUDY. BACKGROUND THE BIOLOGICAL MECHANISMS OF HEADACHE CHRONIFICATION ARE POORLY UNDERSTOOD. WE AIMED TO IDENTIFY CHANGES IN DNA METHYLATION ASSOCIATED WITH THE TRANSFORMATION FROM EPISODIC TO CHRONIC HEADACHE. METHODS PARTICIPANTS WERE RECRUITED FROM THE POPULATION-BASED NORWEGIAN HUNT STUDY. THIRTY-SIX FEMALE HEADACHE PATIENTS WHO TRANSFORMED FROM EPISODIC TO CHRONIC HEADACHE BETWEEN BASELINE AND FOLLOW-UP 11 YEARS LATER WERE MATCHED AGAINST 35 CONTROLS WITH EPISODIC HEADACHE. DNA METHYLATION WAS QUANTIFIED AT 485,000 CPG SITES, AND CHANGES IN METHYLATION LEVEL AT THESE SITES WERE COMPARED BETWEEN CASES AND CONTROLS BY LINEAR REGRESSION ANALYSIS. DATA WERE ANALYZED IN TWO STAGES (STAGES 1 AND 2) AND IN A COMBINED META-ANALYSIS. RESULTS NONE OF THE TOP 20 CPG SITES IDENTIFIED IN STAGE 1 REPLICATED IN STAGE 2 AFTER MULTIPLE TESTING CORRECTION. IN THE COMBINED META-ANALYSIS THE STRONGEST ASSOCIATED CPG SITES WERE RELATED TO SH2D5 AND NPTX2, TWO BRAIN-EXPRESSED GENES INVOLVED IN THE REGULATION OF SYNAPTIC PLASTICITY. FUNCTIONAL ENRICHMENT ANALYSIS POINTED TO PROCESSES INCLUDING CALCIUM ION BINDING AND ESTROGEN RECEPTOR PATHWAYS. CONCLUSION IN THIS FIRST GENOME-WIDE STUDY OF DNA METHYLATION IN HEADACHE CHRONIFICATION SEVERAL POTENTIALLY IMPLICATED LOCI AND PROCESSES WERE IDENTIFIED. THE STUDY EXEMPLIFIES THE USE OF PROSPECTIVELY COLLECTED POPULATION COHORTS TO SEARCH FOR EPIGENETIC MECHANISMS OF DISEASE. 2018