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  1784  43 EFFECT OF ALCOHOL CONSUMPTION ON CPG METHYLATION IN THE DIFFERENTIALLY METHYLATED REGIONS OF H19 AND IG-DMR IN MALE GAMETES: IMPLICATIONS FOR FETAL ALCOHOL SPECTRUM DISORDERS. BACKGROUND: EXPOSURE TO ALCOHOL IN UTERO IS THE MAIN ATTRIBUTABLE CAUSE OF FETAL ALCOHOL SPECTRUM DISORDERS (FASD) WHICH IN ITS MOST SEVERE FORM IS CHARACTERIZED BY IRREVERSIBLE BEHAVIORAL AND COGNITIVE DISABILITY. PATERNAL PRECONCEPTION DRINKING IS NOT CONSIDERED TO BE A SIGNIFICANT RISK FACTOR, EVEN THOUGH ANIMAL STUDIES HAVE DEMONSTRATED THAT CHRONIC PATERNAL ALCOHOL CONSUMPTION HAS A DETRIMENTAL EFFECT ON THE PHYSICAL AND MENTAL DEVELOPMENT OF OFFSPRING EVEN IN THE ABSENCE OF IN UTERO ALCOHOL EXPOSURE. IT HAS BEEN DOCUMENTED THAT ALCOHOL CAN REDUCE THE LEVELS AND ACTIVITY OF DNA METHYLTRANSFERASES RESULTING IN DNA HYPOMETHYLATION AND THAT REDUCED METHYLTRANSFERASE ACTIVITY CAN CAUSE ACTIVATION OF NORMALLY SILENCED GENES. THE AIM OF THIS STUDY WAS TO ESTABLISH A LINK BETWEEN ALCOHOL USE IN MEN AND HYPOMETHYLATION OF PATERNALLY IMPRINTED LOCI IN SPERM DNA IN GENOMIC REGIONS CRITICAL FOR EMBRYONIC DEVELOPMENT, THUS PROVIDING A MECHANISM FOR PATERNAL EFFECTS IN THE AETIOLOGY OF FASD. METHODS: SPERM DNA FROM MALE VOLUNTEERS WAS BISULFITE TREATED AND THE METHYLATION PATTERNS OF 2 DIFFERENTIALLY METHYLATED REGIONS (DMRS), H19 AND IG-DMR, ANALYZED FOLLOWING SEQUENCING OF INDIVIDUAL CLONES. THE METHYLATION PATTERNS WERE CORRELATED WITH THE ALCOHOL CONSUMPTION LEVELS OF THE VOLUNTEER MALES. RESULTS: THERE WAS A PATTERN OF INCREASED DEMETHYLATION WITH ALCOHOL CONSUMPTION AT THE 2 IMPRINTED LOCI WITH A SIGNIFICANT DIFFERENCE OBSERVED AT THE IG-DMR BETWEEN THE NONDRINKING AND HEAVY ALCOHOL CONSUMING GROUPS. GREATER INTER-INDIVIDUAL VARIATION IN AVERAGE METHYLATION WAS OBSERVED AT THE H19 DMR AND INDIVIDUAL CLONES WERE MORE EXTENSIVELY DEMETHYLATED THAN THOSE OF THE IG-DMR. CPG SITE #4 IN THE IG-DMR WAS PREFERENTIALLY DEMETHYLATED AMONG ALL INDIVIDUALS AND ALONG WITH THE H19 DMR CPG SITE #7 LOCATED WITHIN THE CTCF BINDING SITE 6 SHOWED SIGNIFICANT DEMETHYLATION IN THE ALCOHOL CONSUMING GROUPS COMPARED WITH THE CONTROL GROUP. CONCLUSION: THIS STUDY DEMONSTRATES A CORRELATION BETWEEN CHRONIC ALCOHOL USE AND DEMETHYLATION OF NORMALLY HYPERMETHYLATED IMPRINTED REGIONS IN SPERM DNA. WE HYPOTHESIZE THAT, SHOULD THESE EPIGENETIC CHANGES IN IMPRINTED GENES BE TRANSMITTED THROUGH FERTILIZATION, THEY WOULD ALTER THE CRITICAL GENE EXPRESSION DOSAGES REQUIRED FOR NORMAL PRENATAL DEVELOPMENT RESULTING IN OFFSPRING WITH FEATURES OF FASD.	2009	

3  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	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  
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   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	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              
6  2374  51 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	
                                                           
7  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	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
8  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	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  
9  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	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                
10  2920  37 GENE-SET ANALYSIS IS SEVERELY BIASED WHEN APPLIED TO GENOME-WIDE METHYLATION DATA. MOTIVATION: DNA METHYLATION IS AN EPIGENETIC MARK THAT CAN STABLY REPRESS GENE EXPRESSION. BECAUSE OF ITS BIOLOGICAL AND CLINICAL SIGNIFICANCE, SEVERAL METHODS HAVE BEEN DEVELOPED TO COMPARE GENOME-WIDE PATTERNS OF METHYLATION BETWEEN GROUPS OF SAMPLES. THE APPLICATION OF GENE SET ANALYSIS TO IDENTIFY RELEVANT GROUPS OF GENES THAT ARE ENRICHED FOR DIFFERENTIALLY METHYLATED GENES IS OFTEN A MAJOR COMPONENT OF THE ANALYSIS OF THESE DATA. THIS CAN BE USED, FOR EXAMPLE, TO IDENTIFY PROCESSES OR PATHWAYS THAT ARE PERTURBED IN DISEASE DEVELOPMENT. WE SHOW THAT GENE-SET ANALYSIS, AS IT IS TYPICALLY APPLIED TO GENOME-WIDE METHYLATION ASSAYS, IS SEVERELY BIASED AS A RESULT OF DIFFERENCES IN THE NUMBERS OF CPG SITES ASSOCIATED WITH DIFFERENT CLASSES OF GENES AND GENE PROMOTERS. RESULTS: WE DEMONSTRATE THIS BIAS USING PUBLISHED DATA FROM A STUDY OF DIFFERENTIAL CPG ISLAND METHYLATION IN LUNG CANCER AND A DATASET WE GENERATED TO STUDY METHYLATION CHANGES IN PATIENTS WITH LONG-STANDING ULCERATIVE COLITIS. WE SHOW THAT SEVERAL OF THE GENE SETS THAT SEEM ENRICHED WOULD ALSO BE IDENTIFIED WITH RANDOMIZED DATA. WE SUGGEST TWO EXISTING APPROACHES THAT CAN BE ADAPTED TO CORRECT THE BIAS. ACCOUNTING FOR THE BIAS IN THE LUNG CANCER AND ULCERATIVE COLITIS DATASETS PROVIDES NOVEL BIOLOGICAL INSIGHTS INTO THE ROLE OF METHYLATION IN CANCER DEVELOPMENT AND CHRONIC INFLAMMATION, RESPECTIVELY. OUR RESULTS HAVE SIGNIFICANT IMPLICATIONS FOR MANY PREVIOUS GENOME-WIDE METHYLATION STUDIES THAT HAVE DRAWN CONCLUSIONS ON THE BASIS OF SUCH STRONGLY BIASED ANALYSIS. CONTACT: CATHAL.SEOIGHE@NUIGALWAY.IE SUPPLEMENTARY INFORMATION: SUPPLEMENTARY DATA ARE AVAILABLE AT BIOINFORMATICS ONLINE.	2013	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
11  1577  32 DNA METHYLATION PROFILE IN CHRONIC MYELOMONOCYTIC LEUKEMIA ASSOCIATES WITH DISTINCT CLINICAL, BIOLOGICAL AND GENETIC FEATURES. CHROMOSOMAL ABNORMALITIES ARE DETECTED IN 20-30% OF PATIENTS WITH CHRONIC MYELOMONOCYTIC LEUKEMIA (CMML) AND CORRELATE WITH PROGNOSIS. ON THE MUTATION LEVEL, DISRUPTIVE ALTERATIONS ARE PARTICULARLY FREQUENT IN CHROMATIN REGULATORY GENES. HOWEVER, LITTLE IS KNOWN ABOUT THE CONSEQUENTIAL ALTERATIONS IN THE EPIGENETIC MARKING OF THE GENOME. HERE, WE REPORT THE ANALYSIS OF GENOMIC DNA METHYLATION PATTERNS OF 64 CMML PATIENTS AND 10 HEALTHY CONTROLS, USING A DNA METHYLATION MICROARRAY FOCUSED ON PROMOTER REGIONS. DIFFERENTIAL METHYLATION ANALYSIS BETWEEN PATIENTS AND CONTROLS ALLOWED US TO IDENTIFY ABNORMALITIES IN DNA METHYLATION, INCLUDING HYPERMETHYLATION OF SPECIFIC GENES AND LARGE GENOME REGIONS WITH ABERRANT DNA METHYLATION. UNSUPERVISED HIERARCHICAL CLUSTER ANALYSIS IDENTIFIED TWO MAIN CLUSTERS THAT ASSOCIATED WITH THE CLINICAL, BIOLOGICAL, AND GENETIC FEATURES OF PATIENTS. GROUP 1 WAS ENRICHED IN PATIENTS WITH ADVERSE CLINICAL AND BIOLOGICAL CHARACTERISTICS AND POORER OVERALL AND PROGRESSION-FREE SURVIVAL. IN ADDITION, SIGNIFICANT DIFFERENCES IN DNA METHYLATION WERE OBSERVED BETWEEN PATIENTS WITH LOW RISK AND INTERMEDIATE/HIGH RISK KARYOTYPES AND BETWEEN TET2 MUTANT AND WILD TYPE PATIENTS. TAKEN TOGETHER, OUR RESULTS DEMONSTRATE THAT ALTERED DNA METHYLATION PATTERNS REFLECT THE CMML DISEASE STATE AND ALLOW TO IDENTIFY PATIENT GROUPS WITH DISTINCT CLINICAL FEATURES.	2018	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     
12  3410  36 HOXA5 UNDERGOES DYNAMIC DNA METHYLATION AND TRANSCRIPTIONAL REPRESSION IN THE ADIPOSE TISSUE OF MICE EXPOSED TO HIGH-FAT DIET. BACKGROUND/OBJECTIVES: THE GENOMIC BASES OF THE ADIPOSE TISSUE ABNORMALITIES INDUCED BY CHRONIC POSITIVE CALORIE EXCESS HAVE BEEN ONLY PARTIALLY ELUCIDATED. WE ADOPTED A GENOME-WIDE APPROACH TO DIRECTLY TEST WHETHER LONG-TERM HIGH-FAT DIET (HFD) EXPOSURE AFFECTS THE DNA METHYLATION PROFILE OF THE MOUSE ADIPOSE TISSUE AND TO IDENTIFY THE FUNCTIONAL CONSEQUENCES OF THESE CHANGES. SUBJECTS/METHODS: WE HAVE USED EPIDIDYMAL FAT OF MICE FED EITHER HIGH-FAT (HFD) OR REGULAR CHOW (STD) DIET FOR 5 MONTHS AND PERFORMED GENOME-WIDE DNA METHYLATION ANALYSES BY METHYLATED DNA IMMUNOPRECIPITATION SEQUENCING (MEDIP-SEQ). MOUSE HOMEOBOX (HOX) GENE DNA METHYLATION PCR, RT-QPCR AND BISULPHITE SEQUENCING ANALYSES WERE THEN PERFORMED. RESULTS: MICE FED THE HFD PROGRESSIVELY EXPANDED THEIR ADIPOSE MASS ACCOMPANIED BY A SIGNIFICANT DECREASE IN GLUCOSE TOLERANCE (P<0.001) AND INSULIN SENSITIVITY (P<0.05). MEDIP-SEQ DATA ANALYSIS REVEALED A UNIFORM DISTRIBUTION OF DIFFERENTIALLY METHYLATED REGIONS (DMR) THROUGH THE ENTIRE ADIPOCYTE GENOME, WITH A HIGHER NUMBER OF HYPERMETHYLATED REGIONS IN HFD MICE (P<0.005). THIS DIFFERENT METHYLATION PROFILE WAS ACCOMPANIED BY INCREASED EXPRESSION OF THE DNMT3A DNA METHYLTRANSFERASE (DNMT; P<0.05) AND THE METHYL-CPG-BINDING DOMAIN PROTEIN MBD3 (P<0.05) GENES IN HFD MICE. GENE ONTOLOGY ANALYSIS REVEALED THAT, IN THE HFD-TREATED MICE, THE HOX FAMILY OF DEVELOPMENT GENES WAS HIGHLY ENRICHED IN DIFFERENTIALLY METHYLATED GENES (P=0.008). TO VALIDATE THIS FINDING, HOXA5, WHICH IS IMPLICATED IN FAT TISSUE DIFFERENTIATION AND REMODELING, HAS BEEN SELECTED AND ANALYZED BY BISULPHITE SEQUENCING, CONFIRMING HYPERMETHYLATION IN THE ADIPOSE TISSUE FROM THE HFD MICE. HOXA5 HYPERMETHYLATION WAS ASSOCIATED WITH DOWNREGULATION OF HOXA5 MRNA AND PROTEIN EXPRESSION. FEEDING ANIMALS PREVIOUSLY EXPOSED TO THE HFD WITH A STANDARD CHOW DIET FOR TWO FURTHER MONTHS IMPROVED THE METABOLIC PHENOTYPE OF THE ANIMALS, ACCOMPANIED BY RETURN OF HOXA5 METHYLATION AND EXPRESSION LEVELS (P<0.05) TO VALUES SIMILAR TO THOSE OF THE CONTROL MICE MAINTAINED UNDER STANDARD CHOW. CONCLUSIONS: HFD INDUCES ADIPOSE TISSUE ABNORMALITIES ACCOMPANIED BY EPIGENETIC CHANGES AT THE HOXA5 ADIPOSE TISSUE REMODELING GENE.	2016	
                                                                                                                                                                                        
13  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	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              
14  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	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   
15  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	
                                                                                                                                                                                                                                                                     
16  1563  29 DNA METHYLATION OF METHYLATION COMPLEX GENES IN RELATION TO STRESS AND GENOME-WIDE METHYLATION IN MOTHER-NEWBORN DYADS. OBJECTIVES: EARLY LIFE STRESS IS KNOWN TO HAVE ENDURING BIOLOGICAL EFFECTS, PARTICULARLY WITH RESPECT TO HEALTH. EPIGENETIC MODIFICATIONS, SUCH AS DNA METHYLATION, ARE A POSSIBLE MECHANISM TO MEDIATE THE BIOLOGICAL EFFECT OF STRESS. WE PREVIOUSLY FOUND CORRELATIONS BETWEEN MATERNAL STRESS, NEWBORN BIRTHWEIGHT, AND GENOME-WIDE MEASURES OF DNA METHYLATION. HERE WE INVESTIGATE TEN GENES RELATED TO THE METHYLATION/DEMETHYLATION COMPLEX IN ORDER TO BETTER UNDERSTAND THE IMPACT OF STRESS ON HEALTH. MATERIALS AND METHODS: DNA METHYLATION AND GENETIC VARIANTS AT METHYLATION/DEMETHYLATION GENES WERE ASSAYED. MEAN METHYLATION MEASURES WERE CONSTRUCTED FOR EACH GENE AND TESTED, IN ADDITION TO GENETIC VARIANTS, FOR ASSOCIATION WITH MATERNAL STRESS MEASURES BASED ON INTERVIEW AND SURVEY DATA (CHRONIC STRESS AND WAR TRAUMA), MATERNAL VENOUS, AND NEWBORN CORD GENOME-WIDE MEAN METHYLATION (GMM), AND BIRTHWEIGHT. RESULTS: AFTER CELL TYPE CORRECTION, WE FOUND MULTIPLE PAIRWISE ASSOCIATIONS BETWEEN WAR TRAUMA, MATERNAL GMM, MATERNAL METHYLATION AT DNMT1, DNMT3A, TET3, AND MBD2, AND BIRTHWEIGHT. CONCLUSIONS: THE ASSOCIATION OF MATERNAL GMM AND MATERNAL METHYLATION AT DNMT1, DNMT3A, TET3, AND MBD2 IS CONSISTENT WITH THE ROLE OF THESE GENES IN ESTABLISHING, MAINTAINING AND ALTERING GENOME-WIDE METHYLATION PATTERNS, IN SOME CASES IN RESPONSE TO STRESS. DNMT1 PRODUCES ONE OF THE PRIMARY ENZYMES THAT REPRODUCES METHYLATION PATTERNS DURING DNA REPLICATION. DNMT3A AND TET3 HAVE BEEN IMPLICATED IN GENOME-WIDE HYPOMETHYLATION IN RESPONSE TO GLUCOCORTICOID HORMONES. ALTHOUGH WE CANNOT DETERMINE THE DIRECTIONALITY OF THE GENIC AND GENOME-WIDE CHANGES IN METHYLATION, OUR RESULTS SUGGEST THAT ALTERED METHYLATION OF SPECIFIC METHYLATION GENES MAY BE PART OF THE MOLECULAR MECHANISM UNDERLYING THE HUMAN BIOLOGICAL RESPONSE TO STRESS.	2018	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     
17  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	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                      
18   101  29 A RAT METHYL-SEQ PLATFORM TO IDENTIFY EPIGENETIC CHANGES ASSOCIATED WITH STRESS EXPOSURE. AS GENOMES OF A WIDER VARIETY OF ANIMALS BECOME AVAILABLE, THERE IS AN INCREASING NEED FOR TOOLS THAT CAN CAPTURE DYNAMIC EPIGENETIC CHANGES IN THESE ANIMAL MODELS. THE RAT IS ONE PARTICULAR MODEL ANIMAL WHERE AN EPIGENETIC TOOL CAN COMPLEMENT MANY PHARMACOLOGICAL AND BEHAVIORAL STUDIES TO PROVIDE INSIGHTFUL MECHANISTIC INFORMATION. TO THIS END, WE ADAPTED THE SURESELECT TARGET CAPTURE SYSTEM (REFERRED TO AS METHYL-SEQ) FOR THE RAT, WHICH CAN ASSESS DNA METHYLATION LEVELS ACROSS THE RAT GENOME. THE RAT DESIGN TARGETED PROMOTERS, CPG ISLANDS, ISLAND SHORES, AND GC-RICH REGIONS FROM ALL REFSEQ GENES. TO IMPLEMENT THE PLATFORM ON A RAT EXPERIMENT, MALE SPRAGUE DAWLEY RATS WERE EXPOSED TO CHRONIC VARIABLE STRESS FOR 3 WEEKS, AFTER WHICH BLOOD SAMPLES WERE COLLECTED FOR GENOMIC DNA EXTRACTION. METHYL-SEQ LIBRARIES WERE CONSTRUCTED FROM THE RAT DNA SAMPLES BY SHEARING, ADAPTER LIGATION, TARGET ENRICHMENT, BISULFITE CONVERSION, AND MULTIPLEXING. LIBRARIES WERE SEQUENCED ON A NEXT-GENERATION SEQUENCING PLATFORM AND THE SEQUENCED READS WERE ANALYZED TO IDENTIFY DMRS BETWEEN DNA OF STRESSED AND UNSTRESSED RATS. TOP CANDIDATE DMRS WERE INDEPENDENTLY VALIDATED BY BISULFITE PYROSEQUENCING TO CONFIRM THE ROBUSTNESS OF THE PLATFORM. RESULTS DEMONSTRATE THAT THE RAT METHYL-SEQ PLATFORM IS A USEFUL EPIGENETIC TOOL THAT CAN CAPTURE METHYLATION CHANGES INDUCED BY EXPOSURE TO STRESS.	2018	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              
19   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	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           
20  5682  33 SHORT-TERM CHANGES IN GLOBAL METHYLATION AND HYDROXYMETHYLATION DURING ALCOHOL DETOXIFICATION. ALCOHOL DEPENDENCE IS A COMMON PUBLIC HEALTH PROBLEM AND EPIGENETICS MAY OFFER NEW ASPECTS IN UNDERSTANDING THE BIOLOGICAL AND GENETIC UNDERPINNINGS AND IMPROVE TREATMENT OF THIS COMPLEX DISEASE. SUPPOSEDLY, METHYLATION AND HYDROXYMETHYLATION ARE ALTERED IN BRAIN TISSUES AND IN SYNAPSE-RELATED GENES DUE TO CHRONIC ALCOHOL INTAKE AND DURING WITHDRAWAL. TO ASSESS POTENTIAL EPIGENETIC CHANGES AFTER CESSATION OF CHRONIC ALCOHOL INTAKE, WE COMPARED 23 ALCOHOL-DEPENDENT INDIVIDUALS DURING INPATIENT ALCOHOL DETOXIFICATION WITH 13 CAREFULLY MATCHED CONTROLS. BLOOD SAMPLES WERE TAKEN ON THE DAY OF ADMISSION, AFTER ONE AND AFTER TWO WEEKS AT THE END OF INPATIENT TREATMENT. GENOME-WIDE GLOBAL METHYLATION AND GLOBAL DNA HYDROXYMETHYLATION WERE COMPARED ACROSS GROUPS. THERE WERE SIGNIFICANT DIFFERENCES IN GLOBAL METHYLATION ACROSS TIME FROM ADMISSION TO ONE AND TWO WEEKS OF INPATIENT WITHDRAWAL (P < 0.001). THESE FINDINGS WERE PARALLELED TO CHANGES IN GLOBAL DNA HYDROXYMETHYLATION ACROSS TIME WHEN AGE WAS EMPLOYED AS A COFACTOR (P < 0.001). SEVERAL POTENTIALLY INFLUENCING VARIABLES LIKE SEVERITY OF WITHDRAWAL, DOSE OF WITHDRAWAL MEDICATION AND ALCOHOL INTAKE BEFORE ADMISSION DID NOT YIELD SIGNIFICANT INFLUENCE ON EPIGENETIC CHANGES. THE RESULTS CONFIRM PREVIOUS FINDINGS OF SIGNIFICANT ALTERATIONS OF EPIGENETIC PATTERNS DURING ALCOHOL INTOXICATION AND PRESENT FOR THE FIRST TIME HYDROXYMETHYLATION CHANGES IN THESE INDIVIDUALS.	2019