1 411 136 ANALYSIS OF GENOME-WIDE DNA METHYLATION PATTERNS IN OBESITY. OBESITY IS A CHRONIC AND COMPLEX PSYCHOSOMATIC DISEASE THAT IS BECOMING INCREASINGLY PREVALENT WORLDWIDE. THIS STUDY AIMED TO ANALYZE WHOLE METHYLATION PROFILES TO UNCOVER THE EPIGENETIC MECHANISMS ASSOCIATED WITH OBESITY. DNA METHYLATION PROFILES IN BLOOD SAMPLES FROM PATIENTS WITH OBESITY AND NORMAL CONTROLS WERE STUDIED USING THE ILLUMINA 850 K METHYLATION MICROARRAY. THE DIAGNOSTIC VALUE OF THE DIFFERENTIALLY METHYLATED GENES WAS DETERMINED USING RECEIVER OPERATING CHARACTERISTIC (ROC) ANALYSIS. THE EXPRESSION OF SELECTED CANDIDATE GENES WAS VERIFIED USING REVERSE TRANSCRIPTION QUANTITATIVE POLYMERASE CHAIN REACTION (RT-QPCR) AND PYROSEQUENCING. A TOTAL OF 9,371 SIGNIFICANTLY DIFFERENTIALLY METHYLATED SITES (7,974 HYPERMETHYLATED SITES AND 1,397 HYPOMETHYLATED SITES) WERE IDENTIFIED IN 4,571 GENES. A DIFFERENCE IN THE DISTRIBUTION OF DIFFERENTIALLY METHYLATED SITES (HYPERMETHYLATED AND HYPOMETHYLATED) IN BOTH GENE STRUCTURES AND CPG ISLANDS WAS OBSERVED. A TOTAL OF 114 KEY DIFFERENTIALLY METHYLATED SITES WERE IDENTIFIED IN THE CPG ISLANDS. ROC RESULTS INDICATED THAT INHIBIN SUBUNIT BETA B (INHBB), HOMEOBOX A9 (HOXA9), TROPONIN T3 (TNNT3), CYCLIC ADENOSINE MONOPHOSPHATE (CAMP)-RESPONSIVE ELEMENT BINDING PROTEIN (CREB)-REGULATED TRANSCRIPTION COACTIVATOR 1 (CRTC1) AND ZINC FINGER AND BTB DOMAIN-CONTAINING 7 B (ZBTB7B) COULD DISCRIMINATE PATIENTS WITH OBESITY FROM NORMAL CONTROLS. RT-QPCR RESULTS OF CRTC1 AND ZBTB7B WERE CONSISTENT WITH OUR METHYLATION PROFILE RESULTS. THE PYROSEQUENCING RESULTS SHOWED THAT THE METHYLATION LEVELS OF CRTC1 CPG SITES (CPG1 AND CPG2-CG11660071) AND INHBB CPG SITES (CPG2) WERE SIGNIFICANTLY CHANGED IN PATIENTS WITH OBESITY COMPARED WITH NORMAL CONTROLS, WHICH WAS CONSISTENT WITH OUR DNA METHYLATION PROFILE RESULTS. OUR STUDY PROVIDES NEW INSIGHTS INTO THE PATHOLOGICAL MECHANISM OF OBESITY. 2021 2 1846 33 EFFECTS OF TWO TYPES OF ENERGY RESTRICTION ON METHYLATION LEVELS OF ADIPONECTIN RECEPTOR 1 AND LEPTIN RECEPTOR OVERLAPPING TRANSCRIPT IN A MOUSE MAMMARY TUMOUR VIRUS-TRANSFORMING GROWTH FACTOR-ALPHA BREAST CANCER MOUSE MODEL. THE ROLE OF ADIPONECTIN AND LEPTIN SIGNALLING PATHWAYS HAS BEEN SUGGESTED TO PLAY IMPORTANT ROLES IN THE PROTECTIVE EFFECTS OF ENERGY RESTRICTION (ER) ON MAMMARY TUMOUR (MT) DEVELOPMENT. TO STUDY THE EFFECTS OF ER ON THE METHYLATION LEVELS IN ADIPONECTIN RECEPTOR 1 (ADIPOR1) AND LEPTIN RECEPTOR OVERLAPPING TRANSCRIPT (LEPROT) GENES USING THE PYROSEQUENCING METHOD IN MAMMARY FAT PAD TISSUE, MOUSE MAMMARY TUMOUR VIRUS-TRANSFORMING GROWTH FACTOR-ALPHA (MMTV-TGF-ALPHA) FEMALE MICE WERE RANDOMLY ASSIGNED TO AD LIBITUM (AL), CHRONIC ER (CER, 15 % ER) OR INTERMITTENT ER (3 WEEKS AL AND 1 WEEK 60 % ER IN CYCLIC PERIODS) GROUPS AT 10 WEEKS OF AGE UNTIL 82 WEEKS OF AGE. THE METHYLATION LEVELS OF ADIPOR1 IN THE CER GROUP WERE HIGHER THAN THOSE IN THE AL GROUP AT WEEK 49/50 (P < 0.05), WHILE THE LEVELS OF METHYLATION FOR ADIPOR1 AND LEPROT GENES WERE SIMILAR AMONG THE OTHER GROUPS. ALSO, THE METHYLATION LEVELS AT CPG2 AND CPG3 REGIONS OF THE PROMOTER REGION OF THE ADIPOR1 GENE IN THE CER GROUP WERE THREE TIMES HIGHER (P < 0.05), WHILE CPG1 ISLAND OF LEPROT METHYLATION WAS SIGNIFICANTLY LOWER COMPARED WITH THE OTHER GROUPS (P < 0.05). ADIPONECTIN AND LEPTIN GENE EXPRESSION LEVELS WERE CONSISTENT WITH THE METHYLATION LEVELS. WE ALSO OBSERVED A CHANGE WITH AGEING IN METHYLATION LEVELS OF THESE GENES. THESE RESULTS INDICATE THAT DIFFERENT TYPES OF ER MODIFY METHYLATION LEVELS OF ADIPOR1 AND LEPROT IN DIFFERENT WAYS AND CER HAD A MORE SIGNIFICANT EFFECT ON METHYLATION LEVELS OF BOTH GENES. EPIGENETIC REGULATION OF THESE GENES MAY PLAY IMPORTANT ROLES IN THE PREVENTIVE EFFECTS OF ER AGAINST MT DEVELOPMENT AND AGEING PROCESSES. 2021 3 1990 39 EPIGENETIC ANALYSIS OF PAGET'S DISEASE OF BONE IDENTIFIES DIFFERENTIALLY METHYLATED LOCI THAT PREDICT DISEASE STATUS. PAGET'S DISEASE OF BONE (PDB) IS CHARACTERIZED BY FOCAL INCREASES IN DISORGANIZED BONE REMODELING. THIS STUDY AIMS TO CHARACTERIZE PDB-ASSOCIATED CHANGES IN DNA METHYLATION PROFILES IN PATIENTS' BLOOD. META-ANALYSIS OF DATA FROM THE DISCOVERY AND CROSS-VALIDATION SET, EACH COMPRISING 116 PDB CASES AND 130 CONTROLS, REVEALED SIGNIFICANT DIFFERENCES IN DNA METHYLATION AT 14 CPG SITES, 4 CPG ISLANDS, AND 6 GENE-BODY REGIONS. THESE LOCI, INCLUDING TWO CHARACTERIZED AS FUNCTIONAL THROUGH EXPRESSION QUANTITATIVE TRAIT-METHYLATION ANALYSIS, WERE ASSOCIATED WITH FUNCTIONS RELATED TO OSTEOCLAST DIFFERENTIATION, MECHANICAL LOADING, IMMUNE FUNCTION, AND VIRAL INFECTION. A MULTIVARIATE CLASSIFIER BASED ON DISCOVERY SAMPLES WAS FOUND TO DISCRIMINATE PDB CASES AND CONTROLS FROM THE CROSS-VALIDATION WITH A SENSITIVITY OF 0.84, SPECIFICITY OF 0.81, AND AN AREA UNDER CURVE OF 92.8%. IN CONCLUSION, THIS STUDY HAS SHOWN FOR THE FIRST TIME THAT EPIGENETIC FACTORS CONTRIBUTE TO THE PATHOGENESIS OF PDB AND MAY OFFER DIAGNOSTIC MARKERS FOR PREDICTION OF THE DISEASE. 2021 4 3125 28 GHSR DNA HYPERMETHYLATION IS A COMMON EPIGENETIC ALTERATION OF HIGH DIAGNOSTIC VALUE IN A BROAD SPECTRUM OF CANCERS. IDENTIFICATION OF A SINGLE MOLECULAR TRAIT THAT IS DETERMINANT OF COMMON MALIGNANCIES MAY SERVE AS A POWERFUL DIAGNOSTIC SUPPLEMENT TO CANCER TYPE-SPECIFIC MARKERS. HERE, WE REPORT A DNA METHYLATION MARK THAT IS CHARACTERISTIC OF SEVEN STUDIED MALIGNANCIES, NAMELY CANCERS OF LUNG, BREAST, PROSTATE, PANCREAS, COLORECTUM, GLIOBLASTOMA AND B CELL CHRONIC LYMPHOCYTIC LEUKAEMIA (CLL) (N = 137). THIS MARK WAS DEFINED BY SUBSTANTIAL HYPERMETHYLATION AT THE PROMOTER AND FIRST EXON OF GROWTH HORMONE SECRETAGOUGE RECEPTOR (GHSR) THROUGH BISULFITE PYROSEQUENCING. THE DEGREE OF ABERRANT METHYLATION WAS CAPABLE OF ACCURATE DISCRIMINATION BETWEEN CANCER AND CONTROL SAMPLES. THE HIGHEST SENSITIVITY AND SPECIFICITY OF CANCER DETECTION WAS ACHIEVED FOR CANCERS OF PANCREAS, LUNG, BREAST AND CLL YIELDING THE AREA UNDER THE CURVE (AUC) VALUES OF 1.0000, 0.9952, 0.9800 AND 0.9400, RESPECTIVELY. NARROWING TO A SINGLE CPG SITE WITHIN THE GENE'S PROMOTER OR FOUR CONSECUTIVE CPG UNITS OF THE HIGHEST METHYLATION LEVELS WITHIN THE FIRST EXON IMPROVED THE DETECTION POWER. GHSR HYPERMETHYLATION WAS DETECTED ALREADY AT THE EARLY STAGE TUMORS. THE ACCURATE PERFORMANCE OF THIS MARKER WAS FURTHER REPLICATED IN AN INDEPENDENT SET OF PANCREATIC CANCER AND CONTROL SAMPLES (N = 78). THESE FINDINGS SUPPORT THE CANDIDATURE OF GHSR METHYLATION AS A HIGHLY ACCURATE PAN-CANCER MARKER. 2015 5 494 31 ASSESSMENT OF PROMOTER METHYLATION IDENTIFIES PTCH AS A PUTATIVE TUMOR-SUPPRESSOR GENE IN HUMAN CLL. BACKGROUND: CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) IS CHARACTERIZED BY A CLONAL ACCUMULATION OF NEOPLASTIC LYMPHOCYTES, INDICATING DISRUPTION OF APOPTOSIS. PATIENTS AND METHODS: DIFFERENTIAL METHYLATION HYBRIDIZATION ANALYSIS WAS PERFORMED TO IDENTIFY NOVEL TARGET GENES SILENCED BY CPG ISLAND METHYLATION IN PATIENTS WITH CLL. RESULTS: PATCHED (PTCH), A TUMOR-SUPPRESSOR GENE, WAS FOUND TO BE FREQUENTLY METHYLATED IN CLL SAMPLES COMPARED TO SAMPLES DERIVED FROM HEALTHY INDIVIDUALS. DE NOVO METHYLATION OF A CPG ISLAND REGION LOCATED UPSTREAM OF PTCH EXON 1 WAS CONFIRMED BY PYROSEQUENCING IN 17/37 (46%) OF PERIPHERAL BLOOD MONONUCLEAR CELLS OF PATIENTS WITH CLL, BUT IN NONE ISOLATED FROM SEVEN HEALTHY INDIVIDUALS. NO ASSOCIATION WAS FOUND BETWEEN PTCH HYPERMETHYLATION AND CURRENTLY USED PROGNOSTIC CLL FACTORS. CONCLUSION: OUR INVESTIGATION SUGGESTS THAT EPIGENETIC SILENCING OF PTCH IS A MECHANISM CONTRIBUTING TO CLL TUMORIGENESIS. 2016 6 4221 43 METHYLATION AND SILENCING OF PROTEIN TYROSINE PHOSPHATASE RECEPTOR TYPE O IN CHRONIC LYMPHOCYTIC LEUKEMIA. PURPOSE: PREVIOUS STUDIES IN OUR LABORATORY HAVE SHOWN THE PROGRESSIVE METHYLATION AND SUPPRESSION OF THE GENE ENCODING PROTEIN TYROSINE PHOSPHATASE, PTPRO, IN THE LIVERS OF RATS FED A METHYL-DEFICIENT DIET THAT INDUCES HEPATOCARCINOGENESIS. SUBSEQUENTLY, WE OBSERVED THE METHYLATION OF PTPRO IN PRIMARY HUMAN LUNG TUMORS AND ALSO SHOWED ITS POTENTIAL TUMOR SUPPRESSOR CHARACTERISTICS. THE PRESENT STUDY WAS UNDERTAKEN TO INVESTIGATE WHETHER THE TRUNCATED FORM OF PTPRO (PTPROT), SPECIFICALLY EXPRESSED IN NAIVE B LYMPHOCYTES, WAS ALSO METHYLATED AND SUPPRESSED IN CHRONIC LYMPHOCYTIC LEUKEMIA (CLL), A DISEASE GENERALLY AFFECTING B LYMPHOCYTES. EXPERIMENTAL DESIGN AND RESULTS: INITIAL SCREENING SHOWED THAT 60% OF THE 52 CLL SAMPLES ANALYZED USING METHYLATION-SPECIFIC PCR ASSAY WERE METHYLATED COMPARED WITH B LYMPHOCYTES FROM NORMAL INDIVIDUALS, WHICH WERE NOT METHYLATED. THE EXPRESSION OF PTPROT, AS MEASURED BY SEMIQUANTITATIVE REVERSE TRANSCRIPTION-PCR, INVERSELY CORRELATED WITH METHYLATION IN THE FEW SAMPLES TESTED. ANALYSIS OF ADDITIONAL SAMPLES (N = 50) BY COMBINED BISULFITE RESTRICTION ANALYSIS SHOWED THAT THE PTPRO CPG ISLAND WAS METHYLATED IN 82% OF PATIENTS WITH CLL COMPARED WITH B LYMPHOCYTES FROM NORMAL INDIVIDUALS. FURTHERMORE, OVERALL EXPRESSION OF PTPRO WAS REDUCED IN CLL RELATIVE TO NORMAL LYMPHOCYTES. THE PTPRO GENE WAS ALSO SUPPRESSED BY METHYLATION IN THE CLL CELL LINE WAC3CD5, WHERE IT COULD BE REACTIVATED UPON TREATMENT WITH THE DNA HYPOMETHYLATING AGENT 5-AZAC. ECTOPIC EXPRESSION OF PTPROT IN A NONEXPRESSING CELL LINE INCREASED GROWTH INHIBITION WITH FLUDARABINE TREATMENT, A THERAPY COMMONLY USED FOR CLL. CONCLUSION: THIS STUDY REVEALS THE POTENTIAL ROLE OF PTPRO METHYLATION AND SILENCING IN CLL TUMORIGENESIS AND ALSO PROVIDES A NOVEL MOLECULAR TARGET IN THE EPIGENETIC THERAPY. 2007 7 2626 41 EPIGENOME-WIDE ASSOCIATION STUDY IDENTIFIES DNA METHYLATION MARKERS FOR ASTHMA REMISSION IN WHOLE BLOOD AND NASAL EPITHELIUM. BACKGROUND: ASTHMA IS A CHRONIC RESPIRATORY DISEASE WHICH IS NOT CURABLE, YET SOME PATIENTS EXPERIENCE SPONTANEOUS REMISSION. WE HYPOTHESIZED THAT EPIGENETIC MECHANISMS MAY BE INVOLVED IN ASTHMA REMISSION. METHODS: CLINICAL REMISSION (CLINR) WAS DEFINED AS THE ABSENCE OF ASTHMA SYMPTOMS AND MEDICATION FOR AT LEAST 12 MONTHS, AND COMPLETE REMISSION (COMR) WAS DEFINED AS CLINR WITH NORMAL LUNG FUNCTION AND ABSENCE OF AIRWAY HYPERRESPONSIVENESS. WE ANALYZED DIFFERENTIAL DNA METHYLATION OF CLINR AND COMR COMPARING TO PERSISTENT ASTHMA (PERSA) IN WHOLE BLOOD SAMPLES (N = 72) AND NASAL BRUSHING SAMPLES (N = 97) IN A LONGITUDINAL COHORT OF WELL CHARACTERIZED ASTHMA PATIENTS. SIGNIFICANT FINDINGS OF WHOLE BLOOD DNA METHYLATION WERE TESTED FOR REPLICATION IN TWO INDEPENDENT COHORTS, LIFELINES AND EPIDEMIOLOGICAL STUDY ON THE GENETICS AND ENVIRONMENT OF ASTHMA (EGEA). RESULTS: WE IDENTIFIED DIFFERENTIALLY METHYLATED CPG SITES ASSOCIATED WITH CLINR (7 CPG SITES) AND COMR (129 CPG SITES) IN WHOLE BLOOD. ONE CPG (CG13378519, CHR1) ASSOCIATED WITH CLINR WAS REPLICATED AND ANNOTATED TO PEX11 (PEROXISOMAL BIOGENESIS FACTOR 11 BETA). THE WHOLE BLOOD DNA METHYLATION LEVELS OF THIS CPG WERE ALSO DIFFERENT BETWEEN CLINR AND HEALTHY SUBJECTS. ONE COMR-ASSOCIATED CPG (CG24788483, CHR10) THAT ANNOTATED TO TCF7L2 (TRANSCRIPTION FACTOR 7 LIKE 2) WAS REPLICATED AND ASSOCIATED WITH EXPRESSION OF TCF7L2 GENE. ONE OUT OF SEVEN CLINR-ASSOCIATED CPG SITES AND 8 OUT OF 129 COMR-ASSOCIATED CPG SITES IDENTIFIED FROM WHOLE BLOOD SAMPLES SHOWED NOMINAL SIGNIFICANCE (P < 0.05) AND THE SAME DIRECTION OF EFFECT IN NASAL BRUSHES. CONCLUSION: WE IDENTIFIED DNA METHYLATION MARKERS POSSIBLY ASSOCIATED WITH CLINICAL AND COMPLETE ASTHMA REMISSION IN NASAL BRUSHES AND WHOLE BLOOD, AND TWO CPG SITES IDENTIFIED FROM WHOLE BLOOD CAN BE REPLICATED IN INDEPENDENT COHORTS AND MAY PLAY A ROLE IN PEROXISOME PROLIFERATION AND WNT SIGNALING PATHWAY. 2020 8 3638 33 INCREASED EXPRESSION OF BETA-DEFENSIN 1 (DEFB1) IN CHRONIC OBSTRUCTIVE PULMONARY DISEASE. ON-GOING AIRWAY INFLAMMATION IS CHARACTERISTIC FOR THE PATHOPHYSIOLOGY OF CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD). HOWEVER, THE KEY FACTORS DETERMINING THE DECREASE IN LUNG FUNCTION, AN IMPORTANT CLINICAL PARAMETER OF COPD, ARE NOT CLEAR. GENOME-WIDE LINKAGE ANALYSES PROVIDE EVIDENCE FOR SIGNIFICANT LINKAGE TO AIRWAY OBSTRUCTION SUSCEPTIBILITY LOCI ON CHROMOSOME 8P23, THE LOCATION OF THE HUMAN DEFENSIN GENE CLUSTER. MOREOVER, A GENETIC VARIATION IN THE DEFENSIN BETA 1 (DEFB1) GENE WAS FOUND TO BE ASSOCIATED WITH COPD. THEREFORE, WE HYPOTHESIZED THAT DEFB1 IS DIFFERENTLY REGULATED AND EXPRESSED IN HUMAN LUNGS DURING COPD PROGRESSION. GENE EXPRESSION OF DEFB1 WAS ASSESSED IN BRONCHIAL EPITHELIUM AND BAL FLUID CELLS OF HEALTHY CONTROLS AND PATIENTS WITH COPD AND USING BISULFITE SEQUENCING AND CHIP ANALYSIS, THE EPIGENETIC CONTROL OF DEFB1 MRNA EXPRESSION WAS INVESTIGATED. WE CAN DEMONSTRATE THAT DEFB1 MRNA EXPRESSION WAS SIGNIFICANTLY INCREASED IN BRONCHOPULMONARY SPECIMEN OF PATIENTS WITH COPD (N = 34) VS. HEALTHY CONTROLS (N = 10) (P<0.0001). FURTHERMORE, A SIGNIFICANT CORRELATION COULD BE DETECTED BETWEEN DEFB1 AND FUNCTIONAL PARAMETERS SUCH AS FEV(1) (P = 0.0024) AND THE FEV(1)/VC RATIO (P = 0.0005). UPREGULATION OF DEFB1 MRNA WAS PARALLELED BY CHANGES IN HDAC1-3, HDAC5 AND HDAC8 MRNA EXPRESSION. WHEREAS BISULFITE SEQUENCING REVEALED NO DIFFERENCES IN THE METHYLATION STATE OF DEFB1 PROMOTER BETWEEN PATIENTS WITH COPD AND CONTROLS, CHIP ANALYSIS SHOWED THAT ENHANCED DEFB1 MRNA EXPRESSION WAS ASSOCIATED WITH THE ESTABLISHMENT OF AN ACTIVE HISTONE CODE. THUS, EXPRESSION OF HUMAN DEFB1 IS UPREGULATED AND RELATED TO THE DECREASE IN PULMONARY FUNCTION IN PATIENTS WITH COPD. 2011 9 5273 40 PROMOTER METHYLATION AND BDNF AND DAT1 GENE EXPRESSION PROFILES IN PATIENTS WITH DRUG ADDICTION. BACKGROUND: DRUG ADDICTION IS A BRAIN DISORDER THAT HAS NEGATIVE CONSEQUENCES FOR INDIVIDUALS AND SOCIETY. ADDICTIONS ARE CHRONIC RELAPSING DISEASES OF THE BRAIN THAT ARE CAUSED BY DIRECT DRUG-INDUCED EFFECTS AND PERSEVERING NEUROADAPTATIONS AT THE EPIGENETIC, NEUROPEPTIDE AND NEUROTRANSMITTER LEVELS. BECAUSE THE DOPAMINERGIC SYSTEM HAS A SIGNIFICANT ROLE IN DRUG ABUSE, THE PURPOSE OF THIS STUDY WAS TO ANALYZE THE METHYLATION AND EXPRESSION PROFILE OF BRAIN-DERIVED NEUROTROPHIC FACTOR (BDNF) AND DOPAMINE TRANSPORTER (DAT1) GENES IN INDIVIDUALS WITH DRUG ADDICTION. MATERIALS AND METHODS: BDNF AND DAT1 PROMOTER METHYLATION WERE INVESTIGATED WITH A METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION (PCR) TECHNIQUE IN BLOOD SAMPLES FROM 75 INDIVIDUALS WITH DRUG ADDICTION AND 65 HEALTHY CONTROLS. THE EXPRESSION LEVELS OF BDNF AND DAT1 WERE ASSESSED IN 12 MRNA SAMPLES FROM THE BLOOD OF PATIENTS AND COMPARED TO THE SAMPLES OF HEALTHY CONTROLS (N = 12) WITH REAL-TIME QUANTITATIVE REVERSE TRANSCRIPTION PCR. RESULTS: NO SIGNIFICANT DIFFERENCES WERE FOUND IN THE METHYLATION OF BDNF AND DAT1 BETWEEN PATIENTS AND CONTROLS, BUT THE RELATIVE LEVELS OF EXPRESSION OF BDNF AND DAT1 MRNA DIFFERED SIGNIFICANTLY IN THE PATIENTS COMPARED TO CONTROLS (P < 0.0001). CONCLUSION: THESE RESULTS SHOWED THAT THE METHYLATION STATUS OF THE BDNF AND DAT1 GENES HAD NO SIGNIFICANT FUNCTION IN THE PROCESSES OF DRUG ADDICTION. 2015 10 11 38 15Q12 VARIANTS, SPUTUM GENE PROMOTER HYPERMETHYLATION, AND LUNG CANCER RISK: A GWAS IN SMOKERS. BACKGROUND: LUNG CANCER IS THE LEADING CAUSE OF CANCER-RELATED MORTALITY WORLDWIDE. DETECTION OF PROMOTER HYPERMETHYLATION OF TUMOR SUPPRESSOR GENES IN EXFOLIATED CELLS FROM THE LUNG PROVIDES AN ASSESSMENT OF FIELD CANCERIZATION THAT IN TURN PREDICTS LUNG CANCER. THE IDENTIFICATION OF GENETIC DETERMINANTS FOR THIS VALIDATED CANCER BIOMARKER SHOULD PROVIDE NOVEL INSIGHTS INTO MECHANISMS UNDERLYING EPIGENETIC REPROGRAMMING DURING LUNG CARCINOGENESIS. METHODS: A GENOME-WIDE ASSOCIATION STUDY USING GENERALIZED ESTIMATING EQUATIONS AND LOGISTIC REGRESSION MODELS WAS CONDUCTED IN TWO GEOGRAPHICALLY INDEPENDENT SMOKER COHORTS TO IDENTIFY LOCI AFFECTING THE PROPENSITY FOR CANCER-RELATED GENE METHYLATION THAT WAS ASSESSED BY A 12-GENE PANEL INTERROGATED IN SPUTUM. ALL STATISTICAL TESTS WERE TWO-SIDED. RESULTS: TWO SINGLE NUCLEOTIDE POLYMORPHISMS (SNPS) AT 15Q12 (RS73371737 AND RS7179575) THAT DROVE GENE METHYLATION WERE DISCOVERED AND REPLICATED WITH RS73371737 REACHING GENOME-WIDE SIGNIFICANCE (P = 3.3X10(-8)). A HAPLOTYPE CARRYING RISK ALLELES FROM THE TWO 15Q12 SNPS CONFERRED 57% INCREASED RISK FOR GENE METHYLATION (P = 2.5X10(-9)). RS73371737 REDUCED GABRB3 EXPRESSION IN LUNG CELLS AND INCREASED RISK FOR SMOKING-INDUCED CHRONIC MUCOUS HYPERSECRETION. FURTHERMORE, SUBJECTS WITH VARIANT HOMOZYGOTE OF RS73371737 HAD A TWO-FOLD INCREASE IN RISK FOR LUNG CANCER (P = .0043). PATHWAY ANALYSIS IDENTIFIED DNA DOUBLE-STRAND BREAK REPAIR BY HOMOLOGOUS RECOMBINATION (DSBR-HR) AS A MAJOR PATHWAY AFFECTING SUSCEPTIBILITY FOR GENE METHYLATION THAT WAS VALIDATED BY MEASURING CHROMATID BREAKS IN LYMPHOCYTES CHALLENGED BY BLEOMYCIN. CONCLUSIONS: A FUNCTIONAL 15Q12 VARIANT WAS IDENTIFIED AS A RISK FACTOR FOR GENE METHYLATION AND LUNG CANCER. THE ASSOCIATIONS COULD BE MEDIATED BY GABAERGIC SIGNALING THAT DRIVES THE SMOKING-INDUCED MUCOUS CELL METAPLASIA. OUR FINDINGS ALSO SUBSTANTIATE DSBR-HR AS A CRITICAL PATHWAY DRIVING EPIGENETIC GENE SILENCING. 2015 11 1598 28 DNA METHYLATION SIGNATURE IN MONONUCLEAR CELLS AND PROINFLAMMATORY CYTOKINES MAY DEFINE MOLECULAR SUBTYPES IN SPORADIC MENIERE DISEASE. MENIERE DISEASE (MD) IS A MULTIFACTORIAL DISORDER OF THE INNER EAR CHARACTERIZED BY VERTIGO ATTACKS ASSOCIATED WITH SENSORINEURAL HEARING LOSS AND TINNITUS WITH A SIGNIFICANT HERITABILITY. ALTHOUGH MD HAS BEEN ASSOCIATED WITH SEVERAL GENES, NO EPIGENETIC STUDIES HAVE BEEN PERFORMED ON MD. HERE WE PERFORMED WHOLE-GENOME BISULFITE SEQUENCING IN 14 MD PATIENTS AND SIX HEALTHY CONTROLS, WITH THE AIM OF IDENTIFYING AN MD METHYLATION SIGNATURE AND POTENTIAL DISEASE MECHANISMS. WE OBSERVED A HIGH NUMBER OF DIFFERENTIALLY METHYLATED CPGS (DMC) WHEN COMPARING MD PATIENTS TO CONTROLS (N= 9545), SEVERAL OF THEM IN HEARING LOSS GENES, SUCH AS PCDH15,&NBSP;ADGRV1 AND CDH23. BIOINFORMATIC ANALYSES OF DMCS AND CIS-REGULATORY REGIONS PREDICTED PHENOTYPES RELATED TO ABNORMAL EXCITATORY POSTSYNAPTIC CURRENTS, ABNORMAL NMDA-MEDIATED RECEPTOR CURRENTS AND ABNORMAL GLUTAMATE-MEDIATED RECEPTOR CURRENTS WHEN COMPARING MD TO CONTROLS. MOREOVER, WE IDENTIFIED VARIOUS DMCS IN GENES PREVIOUSLY ASSOCIATED WITH COCHLEOVESTIBULAR PHENOTYPES IN MICE. WE HAVE ALSO FOUND 12 UNDERMETHYLATED REGIONS (UMR) THAT WERE EXCLUSIVE TO MD, INCLUDING TWO UMR IN AN INTER CPG ISLAND IN THE PHB GENE. WE SUGGEST THAT THE DNA METHYLATION SIGNATURE ALLOWS DISTINGUISHING BETWEEN MD PATIENTS AND CONTROLS. THE ENRICHMENT ANALYSIS CONFIRMS PREVIOUS FINDINGS OF A CHRONIC INFLAMMATORY PROCESS UNDERLYING MD. 2021 12 1529 34 DNA METHYLATION CHANGES IN WHOLE BLOOD AND CD16+ NEUTROPHILS IN RESPONSE TO CHRONIC FOLIC ACID SUPPLEMENTATION IN WOMEN OF CHILDBEARING AGE. FOLATE, A WATER-SOLUBLE VITAMIN, IS A KEY SOURCE OF ONE-CARBON GROUPS FOR DNA METHYLATION, BUT STUDIES OF THE DNA METHYLATION RESPONSE TO SUPPLEMENTAL FOLIC ACID YIELD INCONSISTENT RESULTS. THESE STUDIES ARE COMMONLY CONDUCTED USING WHOLE BLOOD, WHICH CONTAINS A MIXED POPULATION OF WHITE BLOOD CELLS THAT HAVE BEEN SHOWN TO CONFOUND RESULTS. THE OBJECTIVE OF THIS STUDY WAS TO DETERMINE IF CD16+ NEUTROPHILS MAY PROVIDE MORE SPECIFIC DATA THAN WHOLE BLOOD FOR IDENTIFYING DNA METHYLATION RESPONSE TO CHRONIC FOLIC ACID SUPPLEMENTATION. THE STUDY WAS PERFORMED IN NORMAL WEIGHT (BMI 18.5 - 24.9 KG/M2) WOMEN (18 - 35 Y; N = 12), WITH BLOOD SAMPLES TAKEN BEFORE AND AFTER 8 WEEKS OF FOLIC ACID SUPPLEMENTATION AT 800 MUG/DAY. DNA METHYLATION PATTERNS FROM WHOLE BLOOD AND ISOLATED CD16+ NEUTROPHILS WERE MEASURED ACROSS >485,000 CPG SITES THROUGHOUT THE GENOME USING THE INFINIUM HUMANMETHYLATION450 BEADCHIP. OVER THE COURSE OF THE 8-WEEK SUPPLEMENTATION, 6746 AND 7513 CPG SITES CHANGED (P < 0.05) IN WHOLE BLOOD AND CD16+ NEUTROPHILS, RESPECTIVELY. DNA METHYLATION DECREASED IN 68.4% (WHOLE BLOOD) AND 71.8% (CD16+ NEUTROPHILS) OF THESE SITES. THERE WERE ONLY 182 CPG SITES THAT CHANGED IN BOTH THE WHOLE BLOOD AND CD16+ NEUTROPHILS, 139 OF WHICH CHANGED IN THE SAME DIRECTION. THESE RESULTS SUGGEST THAT THE GENOME-WIDE DNA METHYLATION RESPONSE TO CHRONIC FOLIC ACID SUPPLEMENTATION IS DIFFERENT BETWEEN WHOLE BLOOD AND CD16+ NEUTROPHILS AND THAT A SINGLE WHITE BLOOD CELL TYPE MAY FUNCTION AS A MORE SPECIFIC EPIGENETIC REPORTER OF FOLATE STATUS THAN WHOLE BLOOD. 2017 13 2037 33 EPIGENETIC CHANGES OF TIMP-3, GSTP-1 AND 14-3-3 SIGMA GENES AS INDICATION OF STATUS OF CHRONIC INFLAMMATION AND CANCER. OBJECTIVES: THIS STUDY AIMED TO COMPARE THE EPIGENETIC CHANGES VIA HYPERMETHYLATION STATUS OF TIMP-3, GSTP-1 AND 14-3-3SIGMA GENES, BETWEEN HEALTHY SUBJECTS AND PATIENTS WITH REVERSIBLE CHRONIC INFLAMMATORY DISEASE, AND BETWEEN HEALTHY SUBJECTS AND PATIENTS WITH IRREVERSIBLE MALIGNANT DISEASE, TO HIGHLIGHT THE GENETIC CHANGES THAT OCCUR IN THE PROGRESSION FROM AN INFLAMMATORY CONDITION TO IRREVERSIBLE GENETIC CHANGES COMMONLY OBSERVED IN CANCER PATIENTS. METHODS: DNA WAS EXTRACTED FROM THE BLOOD OF 680 HEALTHY SUBJECTS, AND TISSUES AND BLOOD OF 110 PATIENTS WITH CHRONIC INFLAMMATION DISEASE OF THE GUMS, AS WELL AS NEOPLASTIC TISSUES OF 108 BREAST CANCER PATIENTS. METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION (PCR) FOR TIMP-3, GSTP-1 AND 14-3-3SIGMA WAS PERFORMED, AND HYPERMETHYLATION STATUS WAS ANALYZED AND COMPARED BETWEEN THE 3 GROUPS. RESULTS: THE HYPERMETHYLATION FREQUENCIES OF TIMP-3 AND GSTP-1 OF REVERSIBLE CHRONIC INFLAMMATORY GUM DISEASE AND THE CONTROL GROUP WERE SIMILAR, BUT BOTH WERE SIGNIFICANTLY LOWER THAN THOSE FOR MALIGNANT DISEASE PATIENTS (P<0.0001). THE METHYLATION FREQUENCY OF 14-3-3SIGMA IN CHRONIC INFLAMMATORY GUM DISEASE WAS HIGHER THAN IN THE CANCER AND CONTROL GROUPS (P<0.0001). THE METHYLATION OF CPG ISLANDS IN TIMP-3 AND GSTP-1 IN CHRONIC INFLAMMATION PATIENTS OCCURRED AS FREQUENTLY AS IN THE CONTROL GROUP, BUT LESS FREQUENTLY THAN IN BREAST CANCER PATIENTS. HOWEVER, THE EPIGENETIC SILENCING OF 14-3-3SIGMA OCCURRED MORE FREQUENTLY IN THE CHRONIC INFLAMMATION GROUP THAN IN CANCER PATIENTS AND HEALTHY CONTROLS. CONCLUSIONS: THE EPIGENETIC SILENCING OF 14-3-3SIGMA MIGHT BE ESSENTIAL FOR CHRONIC INFLAMMATORY GUM DISEASE. THE EPIGENETIC CHANGES PRESENTED IN CHRONIC INFLAMMATION PATIENTS MIGHT DEMONSTRATE AN IRREVERSIBLE DESTRUCTION IN THE TISSUES OR ORGANS SIMILAR TO CANCER. 2014 14 3866 38 JHDM1D AND HDAC1-3 MRNA EXPRESSION LEVELS IN PERIPHERAL BLOOD MONONUCLEAR CELLS OF PATIENTS WITH SYSTEMIC LUPUS ERYTHEMATOSUS. BACKGROUND: SYSTEMIC LUPUS ERYTHEMATOSUS (SLE) IS A CHRONIC RELAPSING AUTOIMMUNE DISEASE CHARACTERIZED BY PRODUCTION OF AUTOANTIBODIES AGAINST A SERIES OF NUCLEAR ANTIGENS AND BY CHRONIC INFLAMMATION. THE ETIOLOGY OF SLE IS THE RESULT OF INTERACTIONS BETWEEN GENETIC, EPIGENETIC, HORMONAL, AND ENVIRONMENTAL FACTORS. CHANGES IN HISTONE ACETYLATION AND METHYLATION CONTRIBUTE TO STRUCTURAL CHROMATIN MODIFICATIONS. OBJECTIVE: WE STUDIED THE HISTONE DEMETHYLASE JHDM1D AND HISTONE DEACETYLASES HDAC1, HDAC2, AND HDAC3 TRANSCRIPT LEVELS IN PERIPHERAL BLOOD MONONUCLEAR CELLS (PBMCS) FROM PATIENTS DIAGNOSED WITH SYSTEMIC LUPUS ERYTHEMATOSUS (SLE). FURTHERMORE, THE ASSOCIATION OF JHDM1D, HDAC1, HDAC2, AND HDAC3 TRANSCRIPT LEVELS WITH GENDER, AGE, AND MAJOR CLINICAL MANIFESTATIONS WERE ANALYZED. MATERIALS AND METHODS: REAL-TIME QUANTITATIVE POLYMERASE CHAIN REACTION (RQ-PCR) ANALYSIS WAS USED TO DETERMINE JHDM1D, HDAC1, HDAC2, AND HDAC3 MRNA EXPRESSION LEVELS IN PERIPHERAL BLOOD MONONUCLEAR CELLS (PBMCS) FROM 30 PATIENTS WITH SLE AND 36 HEALTHY CONTROLS. RESULTS: SIGNIFICANTLY LOWER HDAC2 TRANSCRIPT LEVELS (P = 0.006785) AND SIGNIFICANTLY HIGHER JHDM1D (P = 0.0000002) AND HDAC1 (P = 0.010581) TRANSCRIPT LEVELS IN SLE PATIENTS WERE OBSERVED COMPARED WITH HEALTHY CONTROLS. HIGHER JHDM1D MRNA EXPRESSION WAS DETECTED IN ACTIVE SLE PATIENTS WHEN COMPARED WITH INACTIVE PATIENTS (P = 0.005). FURTHERMORE, THE JHDM1D TRANSCRIPT LEVELS WERE POSITIVELY CORRELATED WITH DISEASE ACTIVITY (R(S) = 0.368, P = 0.045), WHILE HDAC2 MRNA EXPRESSION WAS POSITIVELY CORRELATED WITH DISEASE DURATION (R(S) = 0.502, P = 0.0047). CONCLUSION: OUR ANALYSES CONFIRMED THE IMPORTANCE OF EPIGENETIC ALTERATIONS (HISTONE DEMETHYLATION AND ACETYLATION) IN SLE ETIOLOGY. MOREOVER, OUR RESULTS SUGGEST THAT THE PRESENCE OF SOME CLINICAL MANIFESTATIONS, LIKE HEMATOLOGICAL DISEASE AND ANTI-RO ANTIBODY, MIGHT BE ASSOCIATED WITH THE DYSREGULATION OF HISTONE DEMETHYLASE AND DEACETYLASES MRNA EXPRESSION LEVELS. 2015 15 2262 39 EPIGENETIC PROFILING IN CHRONIC LYMPHOCYTIC LEUKEMIA REVEALS NOVEL METHYLATION TARGETS. CPG ISLAND METHYLATION IS AN EPIGENETIC ALTERATION THAT CONTRIBUTES TO TUMORIGENESIS BY TRANSCRIPTIONAL INACTIVATION OF GENES. LITTLE IS KNOWN ABOUT THE OVERALL LEVELS OF CPG ISLAND METHYLATION IN CHRONIC LYMPHOCYTIC LEUKEMIA (CLL). TO PROVIDE A BASELINE ESTIMATE OF GLOBAL ABERRANT METHYLATION AND IDENTIFY TARGET SEQUENCES FOR ADDITIONAL INVESTIGATION, WE PERFORMED RESTRICTION LANDMARK GENOMIC SCANNING ON 10 CLL SAMPLES. TWO METHYLATION-SENSITIVE LANDMARK ENZYMES WERE USED (NOTI AND ASCI), ALLOWING ASSESSMENT OF OVER 3000 CPG ISLANDS IN EACH SAMPLE. TUMOR-DERIVED RESTRICTION LANDMARK GENOMIC SCANNING PROFILES WERE COMPARED WITH PROFILES FROM CD19-SELECTED B CELLS FROM NORMAL VOLUNTEERS AND MATCHED NORMAL NEUTROPHILS FROM 4 CLL PATIENTS. WE FOUND 2.5-8.1% (MEAN 4.8%) OF THE CPG ISLANDS IN CLL SAMPLES WERE ABERRANTLY METHYLATED COMPARED WITH CONTROLS, AND THE METHYLATION EVENTS HAD A NONRANDOM DISTRIBUTION (P < 0.0001). FURTHERMORE, WE IDENTIFIED 193 ABERRANTLY METHYLATED SEQUENCES, OF WHICH 93% HAVE CPG ISLAND CHARACTERISTICS AND 90% HAVE HOMOLOGY TO GENES OR EXPRESSED SEQUENCES. ONE SUCH GENE, THE G PROTEIN-COUPLED METABOTROPIC GLUTAMATE RECEPTOR 7 (GRM7), POSSIBLY INHIBITS CYCLIC AMP SIGNALING IN THE INDUCTION OF APOPTOSIS. BISULFITE SEQUENCING OF GRM7 CONFIRMED EXTENSIVE CPG ISLAND METHYLATION, AND TREATMENT WITH 5-AZA-2'-DEOXYCYTIDINE (DECITABINE) RESULTED IN UP-REGULATED EXPRESSION OF SEVERAL GENES IN VITRO WITH CONCURRENT CELLULAR DEPLETION OF DNMT1 PROTEIN. OUR DUAL-ENZYME GLOBAL METHYLATION STUDY SHOWS THAT CLL IS CHARACTERIZED BY WIDESPREAD NONRANDOM CPG ISLAND METHYLATION SIMILAR TO OTHER TUMORS AND PROVIDES A PANEL OF NOVEL METHYLATION TARGETS THAT CAN BE USED IN LARGER STUDIES DESIGNED TO ASSESS IMPACT ON DISEASE PROGRESSION AND SURVIVAL. 2004 16 3084 35 GENOME-WIDE SCREEN OF DNA METHYLATION IDENTIFIES NOVEL MARKERS IN CHILDHOOD OBESITY. EPIGENETIC MODIFICATIONS HAVE BEEN HIGHLIGHTED IN CHRONIC NON-COMMUNICABLE DISEASES. THE AIM OF THIS STUDY WAS TO INVESTIGATE GENOME-WIDE DNA METHYLATION FOR THE IDENTIFICATION OF METHYLATION MARKERS IN OBESITY. WITH OBESE CHINESE PRESCHOOL CHILDREN, WE PERFORMED COMPREHENSIVE DNA METHYLATION PROFILING OF GENE PROMOTERS AND CPG ISLANDS TO DETERMINE THE DIFFERENTIALLY METHYLATED GENES USING METHYLATED DNA IMMUNOPRECIPITATION FOLLOWED BY HYBRIDIZATION TO THE NIMBLEGEN HUMAN DNA METHYLATION 385K PROMOTER PLUS CPG ISLAND MICROARRAY. WE FOUND THAT COMPARED TO LEAN CHILDREN, 251 PROMOTERS AND 575 CGIS WERE DEMETHYLATED, AND 141 PROMOTERS AND 277 CGIS WERE HYPERMETHYLATED IN OBESE CHILDREN, AND THEIR DISTRIBUTION ON CHROMOSOMES WAS IMBALANCED, SHOWING MORE PROMOTERS AND CGIS WITH DEMETHYLATION ON CHROMOSOMES 3, 16, 17 AND 19 AND MORE DIFFERENTIALLY METHYLATED PROMOTERS AND CGIS ON CHROMOSOME X COMPARED WITH CHROMOSOME Y. FURTHER ANALYSIS INDICATED THAT ABERRANT METHYLATIONS OCCURRED MOSTLY IN HCP PROMOTERS AND PROMOTER CGIS. AMONG THE TOP 80 PROMOTERS AND CGIS THAT HAD DIFFERENTIATED METHYLATION BETWEEN OBESE AND LEAN CHILDREN, NEARLY HALF HAVE BEEN PREVIOUSLY STUDIED, AND ALMOST ALL OF THEM ARE INVOLVED IN THE PATHOGENESIS OF CANCERS THAT ARE ASSOCIATED WITH MANY ORGANS. FURTHERMORE, FOUR GENES (FZD7, PRLHR, EXOSC4, AND EIF6) WITH DIFFERENTIAL PROMOTER METHYLATION WERE VALIDATED, AND THEIR ASSOCIATIONS WITH OBESITY MUST BE CLARIFIED. IN CONCLUSION, THIS STUDY REPRESENTS THE FIRST EFFORT TO DETERMINE METHYLATION MARKERS IN OBESE CHINESE CHILDREN, WHICH HAS POTENTIAL RELEVANCE FOR IDENTIFYING MARKERS THAT ARE USEFUL IN ELUCIDATING THE MECHANISMS OF OBESITY PATHOGENESIS AND ITS COMPLICATIONS. 2015 17 155 26 ABERRANT METHYLATION OF POLO-LIKE KINASE CPG ISLANDS IN PLK4 HETEROZYGOUS MICE. BACKGROUND: HEPATOCELLULAR CARCINOMA (HCC), ONE OF THE MOST COMMON CANCERS WORLD-WIDE OCCURS TWICE AS OFTEN IN MEN COMPARED TO WOMEN. PREDISPOSING CONDITIONS SUCH AS ALCOHOLISM, CHRONIC VIRAL HEPATITIS, AFLATOXIN B1 INGESTION, AND CIRRHOSIS ALL CONTRIBUTE TO THE DEVELOPMENT OF HCC. METHODS: WE USED A COMBINATION OF METHYLATION SPECIFIC PCR AND BISULFITE SEQUENCING, QREAL-TIME PCR (QPCR), AND WESTERN BLOT ANALYSIS TO EXAMINE EPIGENETIC CHANGES FOR THE POLO-LIKE KINASES (PLKS) DURING THE DEVELOPMENT OF HEPATOCELLULAR CARCINOMA (HCC) IN PLK4 HETEROZYGOUS MICE AND MURINE EMBRYONIC FIBROBLASTS (MEFS). RESULTS: HERE WE REPORT THAT THE PROMOTER METHYLATION OF PLK4 CPG ISLANDS INCREASES WITH AGE, WAS MORE PREVALENT IN MALES AND THAT PLK4 EPIGENETIC MODIFICATION AND SUBSEQUENT DOWNREGULATION OF EXPRESSION WAS ASSOCIATED WITH THE DEVELOPMENT OF HCC IN PLK4 MUTANT MICE. INTERESTINGLY, THE OPPOSITE OCCURS WITH ANOTHER PLK FAMILY MEMBER, PLK1 WHICH WAS TYPICALLY HYPERMETHYLATED IN NORMAL LIVER TISSUE BUT BECAME HYPOMETHYLATED AND UPREGULATED IN LIVER TUMOURS. FURTHERMORE, UPON ALCOHOL EXPOSURE MURINE EMBRYONIC FIBROBLASTS EXHIBITED INCREASED PLK4 HYPERMETHYLATION AND DOWNREGULATION ALONG WITH INCREASED CENTROSOME NUMBERS AND MULTINUCLEATION. CONCLUSIONS: THESE RESULTS SUGGEST THAT ABERRANT PLK METHYLATION IS CORRELATED WITH THE DEVELOPMENT OF HCC IN MICE. 2011 18 4242 32 METHYLATION STATUS OF ALU AND LINE-1 INTERSPERSED REPETITIVE SEQUENCES IN BEHCET'S DISEASE PATIENTS. BEHCET'S DISEASE (BD) IS A MULTISYSTEM CHRONIC INFLAMMATORY DISEASE. THE PATHOLOGY IS BELIEVED TO INVOLVE BOTH GENETIC SUSCEPTIBILITY AND ENVIRONMENTAL FACTORS. HYPOMETHYLATION LEADING TO ACTIVATION OF INTERSPERSED REPETITIVE SEQUENCES (IRSS) SUCH AS LINE-1 AND ALU CONTRIBUTES TO THE PATHOLOGIES OF AUTOIMMUNE DISEASES AND CANCER. HEREIN, THE EPIGENETIC CHANGES OF IRSS IN BD WERE EVALUATED USING COMBINED BISULFITE RESTRICTION ANALYSIS-INTERSPERSED REPETITIVE SEQUENCES (COBRA-IRS). DNA FROM NEUTROPHILS AND PERIPHERAL BLOOD MONONUCLEAR CELLS (PBMCS) OF BD PATIENTS WITH OCULAR INVOLVEMENT THAT WERE IN ACTIVE OR INACTIVE STATES AND HEALTHY CONTROLS WERE USED TO ANALYZE LINE-1 AND ALU METHYLATION LEVELS. FOR ALU SEQUENCES, SIGNIFICANT DIFFERENCES WERE OBSERVED IN THE FREQUENCY OF (U)C(U)C ALLELES BETWEEN PBMCS OF PATIENTS AND CONTROLS (P = 0.03), AND BETWEEN INACTIVE PATIENTS AND CONTROLS (P = 0.03). FOR NEUTROPHILS, THE FREQUENCY OF (U)C(U)C WAS SIGNIFICANTLY HIGHER BETWEEN PATIENTS AND CONTROLS (P = 0.006) AND BETWEEN INACTIVE PATIENTS AND CONTROLS (P = 0.002). THE PARTIAL METHYLATION ((U)C(M)C + (M)C(U)C) FREQUENCIES OF ALU BETWEEN INACTIVE PATIENTS AND CONTROL SAMPLES ALSO DIFFERED (P = 0.02). NO STATISTICALLY SIGNIFICANT DIFFERENCES FOR LINE-1 WERE DETECTED. THUS, CHANGES IN THE METHYLATION LEVEL OF IRS ELEMENTS MIGHT CONTRIBUTE TO THE PATHOGENESIS OF BD. THE ROLE OF ALU TRANSCRIPTS IN BD SHOULD BE INVESTIGATED FURTHER. 2016 19 1081 32 CLUSTERED PROTOCADHERINS METHYLATION ALTERATIONS IN CANCER. BACKGROUND: CLUSTERED PROTOCADHERINS (PCDHS) MAP IN TANDEM AT HUMAN CHROMOSOME 5Q31 AND COMPRISE THREE MULTI-GENES CLUSTERS: ALPHA-, BETA- AND GAMMA-PCDH. THE EXPRESSION OF THIS CLUSTER CONSISTS OF A COMPLEX MECHANISM INVOLVING DNA HUB FORMATION THROUGH DNA-CCTC BINDING FACTOR (CTCF) INTERACTION. METHYLATION ALTERATIONS CAN AFFECT THIS INTERACTION, LEADING TO TRANSCRIPTIONAL DYSREGULATION. IN CANCER, CLUSTERED PCDHS UNDERGO A MECHANISM OF LONG-RANGE EPIGENETIC SILENCING BY HYPERMETHYLATION. RESULTS: IN THIS STUDY, WE DETECTED FREQUENT METHYLATION ALTERATIONS AT CPG ISLANDS ASSOCIATED TO THESE CLUSTERED PCDHS IN ALL THE SOLID TUMOURS ANALYSED (COLORECTAL, GASTRIC AND BILIARY TRACT CANCERS, PILOCYTIC ASTROCYTOMA), BUT NOT HEMATOLOGIC NEOPLASMS SUCH AS CHRONIC LYMPHOCYTIC LEUKEMIA. IMPORTANTLY, SEVERAL ALTERED CPG ISLANDS WERE ASSOCIATED WITH CTCF BINDING SITES. INTERESTINGLY, OUR ANALYSIS REVEALED A HYPOMETHYLATION EVENT IN PILOCYTIC ASTROCYTOMA, SUGGESTING THAT IN NEURONAL TISSUE, WHERE PCDHS ARE HIGHLY EXPRESSED, THESE GENES BECOME HYPOMETHYLATED IN THIS TYPE OF CANCER. ON THE OTHER HAND, IN TISSUES WHERE PCDHS ARE LOWLY EXPRESSED, THESE CPG ISLANDS ARE TARGETED BY DNA METHYLATION. IN FACT, PCDH-ASSOCIATED CPG ISLANDS RESULTED HYPERMETHYLATED IN GASTROINTESTINAL TUMOURS. CONCLUSIONS: OUR STUDY HIGHLIGHTED A STRONG ALTERATION OF THE CLUSTERED PCDHS METHYLATION PATTERN IN THE ANALYSED SOLID CANCERS AND SUGGESTED THESE METHYLATION ABERRATIONS IN THE CPG ISLANDS ASSOCIATED WITH PCDH GENES AS POWERFUL DIAGNOSTIC BIOMARKERS. 2019 20 3065 38 GENOME-WIDE DNA METHYLATION PATTERNS IN CD4+ T CELLS FROM CHINESE HAN PATIENTS WITH RHEUMATOID ARTHRITIS. INTRODUCTION: RHEUMATOID ARTHRITIS (RA) IS AN AUTOIMMUNE DISEASE THAT CAUSES CHRONIC INFLAMMATION OF THE JOINTS. RECENT EVIDENCE INDICATED THE EPIGENETIC CHANGES MAY CONTRIBUTE TO THE PATHOGENESIS OF RA. METHOD: TO UNDERSTAND THE EXTENT AND NATURE OF DYSREGULATED DNA METHYLATION IN RA CD4T CELLS, WE PERFORMED A GENOME-WIDE DNA METHYLATION STUDY IN CD4 + T CELLS IN 12 RA PATIENTS COMPARED TO 12 MATCHED NORMAL HEALTHY CONTROLS. CYTOSINE METHYLATION STATUS WAS QUANTIFIED WITH ILLUMINA METHYLATION 450K MICROARRAY. RESULT: THE DNA METHYLATION PROFILING SHOWED 383 HYPER- AND 785 HYPO-METHYLATED GENES IN THE CD4 + T CELLS OF THE RA PATIENTS (P < 3.4 X 10(-7)). GENE ONTOLOGY ANALYSIS INDICATED TRANSCRIPT ALTERNATIVE SPLICING AND PROTEIN MODIFICATION MEDIATED BY DNA METHYLATION MIGHT PLAY AN IMPORTANT ROLE IN THE PATHOGENESIS OF RA. IN ADDITION, THE RESULT SHOWED THAT HUMAN LEUKOCYTE ANTIGEN (HLA) REGION INCLUDING HLA-DRB6, HLA-DQA1 AND HLA-E WAS FREQUENTLY HYPOMETHYLATED, BUT HLA-DQB1 HYPERMETHYLATED IN CPG ISLAND REGION AND HYPOMETHYLATED IN CPG SHELF REGION IN RA PATIENTS. OUTSIDE THE MHC REGION, HDAC4, NXN, TBCD AND TMEM61 WERE THE MOST HYPERMETHYLATED GENES, WHILE ITIH3, TCN2, PRDM16, SLC1A5 AND GALNT9 ARE THE MOST HYPOMETHYLATED GENES. CONCLUSION: GENOME-WIDE DNA METHYLATION PROFILE REVEALED SIGNIFICANT DNA METHYLATION CHANGE IN CD4 + T CELLS FROM PATIENTS WITH RA. 2017