1 1081 122 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 2 3125 29 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 3 4221 33 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 4 155 31 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 5 494 29 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 2453 29 EPIGENETIC SUPPRESSION OF THE IMMUNOREGULATOR MZB1 IS ASSOCIATED WITH THE MALIGNANT PHENOTYPE OF GASTRIC CANCER. PREDICTION OF TUMOR RECURRENCE AFTER CURATIVE RESECTION IS CRITICAL FOR DETERMINING THE PROGNOSIS OF PATIENTS WITH GASTRIC CANCER (GC). THE INITIATION AND PROGRESSION OF GC ARE ASSOCIATED WITH INAPPROPRIATE IMMUNE RESPONSES CAUSED BY CHRONIC INFLAMMATION OF THE GASTRIC MUCOSA. TO IDENTIFY IMMUNOREGULATORY MOLECULES INVOLVED IN GC PROGRESSION, GC CELL LINES AND 200 PAIRS OF TUMOR AND NORMAL TISSUES FROM PATIENTS WITH GC WERE ANALYZED FOR GENE EXPRESSION, AMPLIFICATION AND METHYLATION AS WELL AS FUNCTION OF A DIFFERENTIALLY EXPRESSED GENE. THE TRANSCRIPTOME ANALYSIS REVEALED THAT MARGINAL ZONE B AND B1 CELL SPECIFIC PROTEIN (MZB1) WAS EXPRESSED AT SIGNIFICANTLY DECREASED LEVELS IN PRIMARY GC TISSUES WHEN COMPARED WITH THE CORRESPONDING NORMAL GASTRIC MUCOSA. PCR ARRAY ANALYSIS EXPLORING GENES EXPRESSED COOPERATIVELY WITH MZB1 REVEALED THAT DIFFERENTIAL EXPRESSION OF MZB1 MRNA IN GC CELL LINES CORRELATED POSITIVELY WITH THE LEVELS OF THE MRNAS ENCODING ESTROGEN RECEPTOR 1 AND DESUMOYLATING ISOPEPTIDASE 1. HYPERMETHYLATION OF THE MZB1 PROMOTER WAS FREQUENT IN CELL LINES WITH DECREASED LEVELS OF MZB1 MRNA. SIRNA-MEDIATED KNOCKDOWN OF MZB1 SIGNIFICANTLY INCREASED PROLIFERATION, INVASION AND MIGRATION OF GC CELL LINES. LOW MZB1 EXPRESSION WAS AN INDEPENDENT PROGNOSTIC FACTOR FOR RECURRENCE AFTER CURATIVE GASTRECTOMY AND WAS ASSOCIATED SIGNIFICANTLY WITH INCREASED HEMATOGENOUS RECURRENCE. MZB1 ACTS AS A SUPPRESSOR OF GC. LOW MZB1 EXPRESSION IN THE PRIMARY GC TISSUE IS PREDICTIVE OF RECURRENCE AFTER CURATIVE RESECTION. 2016 7 3468 37 HYPOXIA-INDUCED DNA HYPERMETHYLATION IN HUMAN PULMONARY FIBROBLASTS IS ASSOCIATED WITH THY-1 PROMOTER METHYLATION AND THE DEVELOPMENT OF A PRO-FIBROTIC PHENOTYPE. BACKGROUND: PULMONARY FIBROSIS IS A DEBILITATING AND LETHAL DISEASE WITH NO EFFECTIVE TREATMENT OPTIONS. UNDERSTANDING THE PATHOLOGICAL PROCESSES AT PLAY WILL DIRECT THE APPLICATION OF NOVEL THERAPEUTIC AVENUES. HYPOXIA HAS BEEN IMPLICATED IN THE PATHOGENESIS OF PULMONARY FIBROSIS YET THE PRECISE MECHANISM BY WHICH IT CONTRIBUTES TO DISEASE PROGRESSION REMAINS TO BE FULLY ELUCIDATED. IT HAS BEEN SHOWN THAT CHRONIC HYPOXIA CAN ALTER DNA METHYLATION PATTERNS IN TUMOUR-DERIVED CELL LINES. THIS EPIGENETIC ALTERATION CAN INDUCE CHANGES IN CELLULAR PHENOTYPE WITH PROMOTER METHYLATION BEING ASSOCIATED WITH GENE SILENCING. OF PARTICULAR RELEVANCE TO IDIOPATHIC PULMONARY FIBROSIS (IPF) IS THE OBSERVATION THAT THY-1 PROMOTER METHYLATION IS ASSOCIATED WITH A MYOFIBROBLAST PHENOTYPE WHERE LOSS OF THY-1 OCCURS ALONGSIDE INCREASED ALPHA SMOOTH MUSCLE ACTIN (ALPHA-SMA) EXPRESSION. THE INITIAL AIM OF THIS STUDY WAS TO DETERMINE WHETHER HYPOXIA REGULATES DNA METHYLATION IN NORMAL HUMAN LUNG FIBROBLASTS (CCD19LU). AS IT HAS BEEN REPORTED THAT HYPOXIA SUPPRESSES THY-1 EXPRESSION DURING LUNG DEVELOPMENT WE ALSO STUDIED THE EFFECT OF HYPOXIA ON THY-1 PROMOTER METHYLATION AND GENE EXPRESSION. METHODS: CCD19LU WERE GROWN FOR UP TO 8 DAYS IN HYPOXIA AND ASSESSED FOR GLOBAL CHANGES IN DNA METHYLATION USING FLOW CYTOMETRY. REAL-TIME PCR WAS USED TO QUANTIFY EXPRESSION OF THY-1, ALPHA-SMA, COLLAGEN I AND III. GENOMIC DNA WAS BISULPHITE TREATED AND METHYLATION SPECIFIC PCR (MSPCR) WAS USED TO EXAMINE THE METHYLATION STATUS OF THE THY-1 PROMOTER. RESULTS: SIGNIFICANT GLOBAL HYPERMETHYLATION WAS DETECTED IN HYPOXIC FIBROBLASTS RELATIVE TO NORMOXIC CONTROLS AND WAS ACCOMPANIED BY INCREASED EXPRESSION OF MYOFIBROBLAST MARKERS. THY-1 MRNA EXPRESSION WAS SUPPRESSED IN HYPOXIC CELLS, WHICH WAS RESTORED WITH THE DEMETHYLATING AGENT 5-AZA-2'-DEOXYCYTIDINE. MSPCR REVEALED THAT THY-1 BECAME METHYLATED FOLLOWING FIBROBLAST EXPOSURE TO 1% O2. CONCLUSION: THESE DATA SUGGEST THAT GLOBAL AND GENE-SPECIFIC CHANGES IN DNA METHYLATION MAY PLAY AN IMPORTANT ROLE IN FIBROBLAST FUNCTION IN HYPOXIA. 2012 8 4694 32 NEXT-GENERATION SEQUENCING IDENTIFIES MAJOR DNA METHYLATION CHANGES DURING PROGRESSION OF PH+ CHRONIC MYELOID LEUKEMIA. LITTLE IS KNOWN ABOUT THE IMPACT OF DNA METHYLATION ON THE EVOLUTION/PROGRESSION OF PH+ CHRONIC MYELOID LEUKEMIA (CML). WE INVESTIGATED THE METHYLOME OF CML PATIENTS IN CHRONIC PHASE (CP-CML), ACCELERATED PHASE (AP-CML) AND BLAST CRISIS (BC-CML) AS WELL AS IN CONTROLS BY REDUCED REPRESENTATION BISULFITE SEQUENCING. ALTHOUGH ONLY ~600 DIFFERENTIALLY METHYLATED CPG SITES WERE IDENTIFIED IN SAMPLES OBTAINED FROM CP-CML PATIENTS COMPARED WITH CONTROLS, ~6500 DIFFERENTIALLY METHYLATED CPG SITES WERE FOUND IN SAMPLES FROM BC-CML PATIENTS. IN THE MAJORITY OF AFFECTED CPG SITES, METHYLATION WAS INCREASED. IN CP-CML PATIENTS WHO PROGRESSED TO AP-CML/BC-CML, WE IDENTIFIED UP TO 897 GENES THAT WERE METHYLATED AT THE TIME OF PROGRESSION BUT NOT AT THE TIME OF DIAGNOSIS. USING RNA-SEQUENCING, WE OBSERVED DOWNREGULATED EXPRESSION OF MANY OF THESE GENES IN BC-CML COMPARED WITH CP-CML SAMPLES. SEVERAL OF THEM ARE WELL-KNOWN TUMOR-SUPPRESSOR GENES OR REGULATORS OF CELL PROLIFERATION, AND GENE RE-EXPRESSION WAS OBSERVED BY THE USE OF EPIGENETIC ACTIVE DRUGS. TOGETHER, OUR RESULTS DEMONSTRATE THAT CPG SITE METHYLATION CLEARLY INCREASES DURING CML PROGRESSION AND THAT IT MAY PROVIDE A USEFUL BASIS FOR REVEALING NEW TARGETS OF THERAPY IN ADVANCED CML. 2016 9 3296 30 HIGH RESOLUTION INTEGRATIVE ANALYSIS REVEALS WIDESPREAD GENETIC AND EPIGENETIC CHANGES AFTER CHRONIC IN-VITRO ACID AND BILE EXPOSURE IN BARRETT'S EPITHELIUM CELLS. BARRETT'S EPITHELIUM (BE) IS A PREMALIGNANT CONDITION RESULTING FROM CHRONIC GASTROESOPHAGEAL REFLUX THAT MAY PROGRESS TO ESOPHAGEAL ADENOCARCINOMA (EAC). EARLY INTERVENTION HOLDS PROMISE IN PREVENTING BE PROGRESSION. HOWEVER, IDENTIFICATION OF HIGH-RISK BE PATIENTS REMAINS CHALLENGING DUE TO INADEQUATE BIOMARKERS FOR EARLY DIAGNOSIS. WE INVESTIGATED THE EFFECT OF PROLONGED CHRONIC ACID AND BILE EXPOSURE ON TRANSCRIPTOME, METHYLOME, AND MUTATOME OF CELLS IN AN IN-VITRO BE CARCINOGENESIS (BEC) MODEL. TWENTY WEEKS ACID AND BILE EXPOSED CELLS FROM THE BEC MODEL (BEC20W) WERE COMPARED WITH THEIR NAIVE PREDECESSORS HISEQ ILLUMINA BASED RNA SEQUENCING WAS PERFORMED ON RNA FROM BOTH THE CELLS FOR GENE EXPRESSION AND MUTATIONAL ANALYSIS. HELP TAGGING ASSAY WAS PERFORMED FOR DNA METHYLATION ANALYSIS. INGENUITY PATHWAY, GENE ONTOLOGY, AND KEGG PATHWAY ANALYSES WERE THEN PERFORMED ON DATASETS. WIDESPREAD ABERRANT GENETIC AND EPIGENETIC CHANGES WERE OBSERVED IN THE BEC20W CELLS. COMBINATORIAL ANALYSES REVEALED 433 FROM A TOTAL OF 863 DOWNREGULATED GENES HAD ACCOMPANYING HYPERMETHYLATION OF PROMOTERS. SIMULTANEOUSLY, 690 GENES FROM A TOTAL OF 1,492 WERE UPREGULATED WITH ACCOMPANYING PROMOTER HYPOMETHYLATION. IN ADDITION, 763 MUTATIONS WERE IDENTIFIED ON 637 GENES. INGENUITY PATHWAY ANALYSIS, GENE ONTOLOGY, AND KEGG PATHWAY ANALYSES ASSOCIATED THE GENETIC AND EPIGENETIC CHANGES IN BEC20W CELLS WITH CELLULAR AND BIOLOGICAL FUNCTIONS. INTEGRATION OF HIGH RESOLUTION COMPARATIVE ANALYSES OF NAIVE BAR-T AND BEC20W CELLS REVEALED STRIKING GENETIC AND EPIGENETIC CHANGES INDUCED BY CHRONIC ACID AND BILE EXPOSURE THAT MAY DISRUPT NORMAL CELLULAR FUNCTIONS AND PROMOTE CARCINOGENESIS. THIS NOVEL STUDY REVEALS SEVERAL POTENTIAL TARGETS FOR FUTURE BIOMARKERS AND THERAPEUTIC DEVELOPMENT. 2013 10 2637 36 EPIGENOME-WIDE STUDY IDENTIFIES EPIGENETIC OUTLIERS IN NORMAL MUCOSA OF PATIENTS WITH COLORECTAL CANCER. NONGENETIC PREDISPOSITION TO COLORECTAL CANCER CONTINUES TO BE DIFFICULT TO MEASURE PRECISELY, HAMPERING EFFORTS IN TARGETED PREVENTION AND SCREENING. EPIGENETIC CHANGES IN THE NORMAL MUCOSA OF PATIENTS WITH COLORECTAL CANCER CAN SERVE AS A TOOL IN PREDICTING COLORECTAL CANCER OUTCOMES. WE IDENTIFIED EPIGENETIC CHANGES AFFECTING THE NORMAL MUCOSA OF PATIENTS WITH COLORECTAL CANCER. DNA METHYLATION PROFILING ON NORMAL COLON MUCOSA FROM 77 PATIENTS WITH COLORECTAL CANCER AND 68 CONTROLS IDENTIFIED A DISTINCT SUBGROUP OF NORMALLY-APPEARING MUCOSA WITH MARKEDLY DISRUPTED DNA METHYLATION AT A LARGE NUMBER OF CPGS, TERMED AS "OUTLIER METHYLATION PHENOTYPE" (OMP) AND ARE PRESENT IN 15 OF 77 PATIENTS WITH CANCER VERSUS 0 OF 68 CONTROLS (P < 0.001). SIMILAR FINDINGS WERE ALSO SEEN IN PUBLICLY AVAILABLE DATASETS. COMPARISON OF NORMAL COLON MUCOSA TRANSCRIPTION PROFILES OF PATIENTS WITH OMP CANCER WITH THOSE OF PATIENTS WITH NON-OMP CANCER INDICATES GENES WHOSE PROMOTERS ARE HYPERMETHYLATED IN THE OMP PATIENTS ARE ALSO TRANSCRIPTIONALLY DOWNREGULATED, AND THAT MANY OF THE GENES MOST AFFECTED ARE INVOLVED IN INTERACTIONS BETWEEN EPITHELIAL CELLS, THE MUCUS LAYER, AND THE MICROBIOME. ANALYSIS OF 16S RRNA PROFILES SUGGESTS THAT NORMAL COLON MUCOSA OF OMPS ARE ENRICHED IN BACTERIAL GENERA ASSOCIATED WITH COLORECTAL CANCER RISK, ADVANCED TUMOR STAGE, CHRONIC INTESTINAL INFLAMMATION, MALIGNANT TRANSFORMATION, NOSOCOMIAL INFECTIONS, AND KRAS MUTATIONS. IN CONCLUSION, OUR STUDY IDENTIFIES AN EPIGENETICALLY DISTINCT OMP GROUP IN THE NORMAL MUCOSA OF PATIENTS WITH COLORECTAL CANCER THAT IS CHARACTERIZED BY A DISRUPTED METHYLOME, ALTERED GENE EXPRESSION, AND MICROBIAL DYSBIOSIS. PROSPECTIVE STUDIES ARE NEEDED TO DETERMINE WHETHER OMP COULD SERVE AS A BIOMARKER FOR AN ELEVATED EPIGENETIC RISK FOR COLORECTAL CANCER DEVELOPMENT. PREVENTION RELEVANCE: OUR STUDY IDENTIFIES AN EPIGENETICALLY DISTINCT OMP GROUP IN THE NORMAL MUCOSA OF PATIENTS WITH COLORECTAL CANCER THAT IS CHARACTERIZED BY A DISRUPTED METHYLOME, ALTERED GENE EXPRESSION, AND MICROBIAL DYSBIOSIS. IDENTIFICATION OF OMPS IN HEALTHY CONTROLS AND PATIENTS WITH COLORECTAL CANCER WILL LEAD TO PREVENTION AND BETTER PROGNOSIS, RESPECTIVELY. 2022 11 546 28 ATTENUATED EXPRESSION OF SLCO2A1 CAUSED BY DNA METHYLATION IN PEDIATRIC INFLAMMATORY BOWEL DISEASE. BACKGROUND: SLCO2A1 ENCODES A PROSTAGLANDIN (PG) TRANSPORTER, AND AUTOSOMAL RECESSIVE PATHOGENIC VARIANTS OF THIS GENE CAUSE CHRONIC ENTEROPATHY ASSOCIATED WITH SLCO2A1. IT IS UNCLEAR WHETHER A HETEROZYGOUS PATHOGENIC VARIANT OF SLCO2A1 HAS A ROLE IN THE PATHOGENESIS OF OTHER TYPES OF INFLAMMATORY BOWEL DISEASE (IBD). IN THIS STUDY, WE INVESTIGATED THE POSSIBLE INVOLVEMENT OF A LOCAL EPIGENETIC ALTERATION IN SLCO2A1 IN PATIENTS WITH A HETEROZYGOUS PATHOGENIC VARIANT. METHODS: WE CONDUCTED WHOLE-EXOME SEQUENCING OF SAMPLES FROM 2 SISTERS WITH SUSPECTED MONOGENIC IBD. IN ADDITION, WE PERFORMED BISULFITE SEQUENCING USING DNA EXTRACTED FROM THEIR SMALL AND LARGE INTESTINE SAMPLES TO EXPLORE EPIGENETIC ALTERATIONS. RESULTS: A HETEROZYGOUS SPLICING SITE VARIANT, SLCO2A1:C.940 + 1G > A, WAS DETECTED IN BOTH PATIENTS. TO EXPLORE THE POSSIBLE INVOLVEMENT OF EPIGENETIC ALTERATIONS, WE ANALYZED PROTEIN AND MESSENGER RNA EXPRESSION OF SLCO2A1, AND OBSERVED ATTENUATED SLCO2A1 EXPRESSION IN THE INFLAMED LESIONS OF THESE PATIENTS COMPARED WITH THAT IN THE CONTROL INDIVIDUALS. FURTHERMORE, BISULFITE SEQUENCING INDICATED DENSE METHYLATION IN THE PROMOTER REGION OF SLCO2A1 ONLY IN THE INFLAMED LESIONS OF BOTH PATIENTS. THE URINARY PG METABOLITE LEVELS IN THESE PATIENTS WERE COMPARABLE TO THOSE IN PATIENTS WITH CHRONIC ENTEROPATHY ASSOCIATED WITH SLCO2A1 AND HIGHER THAN THOSE IN THE CONTROL INDIVIDUALS. WE FOUND CONSIDERABLY HIGHER LEVELS OF THE METABOLITES IN PATIENT 1, WHO SHOWED MORE SEVERE SYMPTOMS THAN PATIENT 2. CONCLUSIONS: LOCAL DNA METHYLATION ATTENUATED SLCO2A1 EXPRESSION, WHICH MAY EVOKE LOCAL INFLAMMATION OF THE MUCOSA BY THE UNINCORPORATED PG. THESE FINDINGS MAY IMPROVE OUR UNDERSTANDING OF THE EPIGENETIC MECHANISMS UNDERLYING IBD DEVELOPMENT. 2023 12 1995 35 EPIGENETIC AND GENETIC ALTERATIONS AND THEIR INFLUENCE ON GENE REGULATION IN CHRONIC LYMPHOCYTIC LEUKEMIA. BACKGROUND: TO UNDERSTAND THE CHANGES OF GENE REGULATION IN CARCINOGENESIS, WE EXPLORED SIGNALS OF DNA METHYLATION - A STABLE EPIGENETIC MARK OF GENE REGULATORY ELEMENTS - AND DESIGNED A COMPUTATIONAL MODEL TO PROFILE LOSS AND GAIN OF REGULATORY ELEMENTS (RES) DURING CARCINOGENESIS. WE ALSO UTILIZED SEQUENCING DATA TO ANALYZE THE ALLELE FREQUENCY OF SINGLE NUCLEOTIDE POLYMORPHISMS (SNPS) AND DETECTED THE CANCER-ASSOCIATED SNPS, I.E., THE SNPS DISPLAYING THE SIGNIFICANT ALLELE FREQUENCY DIFFERENCE BETWEEN CANCER AND NORMAL SAMPLES. RESULTS: AFTER APPLYING THIS MODEL TO CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) DATA, WE IDENTIFIED RES DIFFERENTIALLY ACTIVATED (DRES) BETWEEN NORMAL AND CLL CELLS, CONSISTING OF 6,802 DRES GAINED AND 4,606 DRES LOST IN CLL. THE IDENTIFIED REGULATORY PERTURBATIONS COINCIDE WITH CHANGES IN THE EXPRESSION OF TARGET GENES. IN PARTICULAR, THE GENES ENCODING DNA METHYLTRANSFERASES HARBOR MULTIPLE LOST-IN-CANCER DRES AND ZERO GAINED-IN-CANCER DRES, INDICATING THAT THE DAMAGED REGULATION OF THESE GENES MIGHT BE ONE OF THE KEY CAUSES OF TUMOR FORMATION. DRES DISPLAY A SIGNIFICANTLY ELEVATED DENSITY OF THE GENOME-WIDE ASSOCIATION STUDY (GWAS) SNPS ASSOCIATED WITH CLL AND CLL-RELATED TRAITS. WE OBSERVED THAT MOST OF DRE GWAS SNPS ASSOCIATED WITH CLL AND CLL-RELATED TRAITS (83%) DISPLAY A SIGNIFICANT HAPLOTYPE ASSOCIATION AMONG THE IDENTIFIED CANCER-ASSOCIATED ALLELES AND THE RISK ALLELES THAT HAVE BEEN REPORTED IN GWAS. ALSO DRES ARE ENRICHED FOR THE BINDING SITES OF THE WELL-ESTABLISHED B-CELL AND CLL TRANSCRIPTION FACTORS (TFS) NF-KB, AP2, P53, E2F1, PAX5, AND SP1. WE ALSO IDENTIFIED CLL-ASSOCIATED SNPS AND DEMONSTRATED THAT THE MUTATIONS AT THESE SNPS CHANGE THE BINDING SITES OF KEY TFS MUCH MORE FREQUENTLY THAN EXPECTED. CONCLUSIONS: THROUGH EXPLORING SEQUENCING DATA MEASURING DNA METHYLATION, WE IDENTIFIED THE EPIGENETIC ALTERATIONS (MORE SPECIFICALLY, DNA METHYLATION) AND GENETIC MUTATIONS ALONG NON-CODING GENOMIC REGIONS CLL, AND DEMONSTRATED THAT THESE CHANGES PLAY A CRITICAL ROLE IN CARCINOGENESIS THROUGH DAMAGING THE REGULATION OF KEY GENES AND ALTERNATING THE BINDING OF KEY TFS IN B AND CLL CELLS. 2017 13 136 30 ABERRANT DNA HYPERMETHYLATION PATTERNS LEAD TO TRANSCRIPTIONAL SILENCING OF TUMOR SUPPRESSOR GENES IN UVB-EXPOSED SKIN AND UVB-INDUCED SKIN TUMORS OF MICE. OVEREXPOSURE OF THE HUMAN SKIN TO SOLAR ULTRAVIOLET (UV) RADIATION IS THE MAJOR ETIOLOGIC FACTOR FOR DEVELOPMENT OF SKIN CANCERS. HERE, WE REPORT THE RESULTS OF EPIGENETIC MODIFICATIONS IN UV-EXPOSED SKIN AND SKIN TUMORS IN A SYSTEMATIC MANNER. THE SKIN AND TUMOR SAMPLES WERE COLLECTED AFTER CHRONIC EXPOSURE OF THE SKIN OF SKH-1 HAIRLESS MICE TO UVB RADIATION USING A WELL-ESTABLISHED PHOTOCARCINOGENESIS PROTOCOL. WE FOUND A DISTINCT DNA HYPERMETHYLATION PATTERN IN THE UVB-EXPOSED EPIDERMAL SKIN AND UVB-INDUCED SKIN TUMORS THAT WAS ASSOCIATED WITH THE ELEVATED EXPRESSION AND ACTIVITY OF THE DNA METHYLTRANSFERASES (DNMT) 1, DNMT3A AND DNMT3B. TO EXPLORE THE ROLE OF HYPERMETHYLATION IN SKIN PHOTOCARCINOGENESIS, WE FOCUSED ON THE P16(INK4A) AND RASSF1A TUMOR SUPPRESSOR GENES, WHICH ARE TRANSCRIPTIONALLY SILENCED ON METHYLATION. WE ESTABLISHED THAT THE SILENCING OF THESE GENES IN UVB-EXPOSED EPIDERMIS AND UVB-INDUCED SKIN TUMORS IS ASSOCIATED WITH A NETWORK OF EPIGENETIC MODIFICATIONS, INCLUDING HYPOACETYLATION OF HISTONE H3 AND H4 AND INCREASED HISTONE DEACETYLATION, AS WELL AS RECRUITMENT OF METHYL-BINDING PROTEINS, INCLUDING MECP2 AND MBD1, TO THE METHYLATED CPGS. HIGHER LEVELS OF DNA METHYLATION AND DNMT ACTIVITY IN HUMAN SQUAMOUS CELL CARCINOMA SPECIMENS THAN IN NORMAL HUMAN SKIN SUGGEST THAT THE DATA ARE RELEVANT CLINICALLY. OUR DATA INDICATE FOR THE FIRST TIME THAT UVB-INDUCED DNA HYPERMETHYLATION, ENHANCED DNMT ACTIVITY AND HISTONE MODIFICATIONS OCCUR IN UVB-EXPOSED SKIN AND UVB-INDUCED SKIN TUMORS AND SUGGEST THAT THESE EVENTS ARE INVOLVED IN THE SILENCING OF TUMOR SUPPRESSOR GENES AND IN SKIN TUMOR DEVELOPMENT. 2011 14 1966 33 EPIGENETIC ALTERATION OF PRKCDBP IN COLORECTAL CANCERS AND ITS IMPLICATION IN TUMOR CELL RESISTANCE TO TNFALPHA-INDUCED APOPTOSIS. PURPOSE: PRKCDBP IS A PUTATIVE TUMOR SUPPRESSOR IN WHICH ALTERATION HAS BEEN OBSERVED IN SEVERAL HUMAN CANCERS. WE INVESTIGATED EXPRESSION AND FUNCTION OF PRKCDBP IN COLORECTAL CELLS AND TISSUES TO EXPLORE ITS CANDIDACY AS A SUPPRESSOR IN COLORECTAL TUMORIGENESIS. EXPERIMENTAL DESIGN: EXPRESSION AND METHYLATION STATUS OF PRKCDBP AND ITS EFFECT ON TUMOR GROWTH WERE EVALUATED. TRANSCRIPTIONAL REGULATION BY NF-KAPPAB SIGNALING WAS DEFINED BY LUCIFERASE REPORTER AND CHROMATIN IMMUNOPRECIPITATION ASSAYS. RESULTS: PRKCDBP EXPRESSION WAS HARDLY DETECTABLE IN 29 OF 80 (36%) PRIMARY TUMORS AND 11 OF 19 (58%) CELL LINES, AND ITS ALTERATION CORRELATED WITH TUMOR STAGE AND GRADE. PROMOTER HYPERMETHYLATION WAS COMMONLY FOUND IN CANCERS. PRKCDBP EXPRESSION INDUCED THE G(1) CELL-CYCLE ARREST AND INCREASED CELLULAR SENSITIVITY TO VARIOUS APOPTOTIC STRESSES. PRKCDBP WAS INDUCED BY TNFALPHA, AND ITS LEVEL CORRELATED WITH TUMOR CELL SENSITIVITY TO TNFALPHA-INDUCED APOPTOSIS. PRKCDBP INDUCTION BY TNFALPHA WAS DISRUPTED BY BLOCKING NF-KAPPAB SIGNALING WHILE IT WAS ENHANCED BY RELA TRANSFECTION. THE PRKCDBP PROMOTER ACTIVITY WAS INCREASED IN RESPONSE TO TNFALPHA, AND THIS RESPONSE WAS ABOLISHED BY DISRUPTION OF A KAPPAB SITE IN THE PROMOTER. PRKCDBP DELAYED THE FORMATION AND GROWTH OF XENOGRAFT TUMORS AND IMPROVED TUMOR RESPONSE TO TNFALPHA-INDUCED APOPTOSIS. CONCLUSIONS: PRKCDBP IS A PROAPOPTOTIC TUMOR SUPPRESSOR WHICH IS COMMONLY ALTERED IN COLORECTAL CANCER BY PROMOTER HYPERMETHYLATION, AND ITS GENE TRANSCRIPTION IS DIRECTLY ACTIVATED BY NF-KAPPAB IN RESPONSE TO TNFALPHA. THIS SUGGESTS THAT PRKCDBP INACTIVATION MAY CONTRIBUTE TO TUMOR PROGRESSION BY REDUCING CELLULAR SENSITIVITY TO TNFALPHA AND OTHER STRESSES, PARTICULARLY UNDER CHRONIC INFLAMMATORY MICROENVIRONMENT. 2011 15 493 26 ASSESSMENT OF P53 AND ATM FUNCTIONALITY IN CHRONIC LYMPHOCYTIC LEUKEMIA BY MULTIPLEX LIGATION-DEPENDENT PROBE AMPLIFICATION. THE ATM-P53 DNA-DAMAGE RESPONSE (DDR) PATHWAY HAS A CRUCIAL ROLE IN CHEMORESISTANCE IN CLL, AS INDICATED BY THE ADVERSE PROGNOSTIC IMPACT OF GENETIC ABERRATIONS OF TP53 AND ATM. IDENTIFYING AND DISTINGUISHING TP53 AND ATM FUNCTIONAL DEFECTS HAS BECOME RELEVANT AS EPIGENETIC AND POSTTRANSCRIPTIONAL DYSREGULATION OF THE ATM/P53 AXIS IS INCREASINGLY BEING RECOGNIZED AS THE UNDERLYING CAUSE OF CHEMORESISTANCE. ALSO, SPECIFIC TREATMENTS SENSITIZING TP53- OR ATM-DEFICIENT CLL CELLS ARE EMERGING. WE THEREFORE DEVELOPED A NEW ATM-P53 FUNCTIONAL ASSAY WITH THE AIM TO (I) IDENTIFY AND (II) DISTINGUISH ABNORMALITIES OF TP53 VERSUS ATM AND (III) ENABLE THE IDENTIFICATION OF ADDITIONAL DEFECTS IN THE ATM-P53 PATHWAY. REVERSED TRANSCRIPTASE MULTIPLEX LIGATION-DEPENDENT PROBE AMPLIFICATION (RT-MLPA) WAS USED TO MEASURE ATM AND/OR P53-DEPENDENT GENES AT THE RNA LEVEL FOLLOWING DNA DAMAGE USING IRRADIATION. HERE, WE SHOWED THAT THIS ASSAY IS ABLE TO IDENTIFY AND DISTINGUISH THREE SUBGROUPS OF CLL TUMORS (I.E., TP53-DEFECTIVE, ATM-DEFECTIVE AND WT) AND IS ALSO ABLE TO DETECT ADDITIONAL SAMPLES WITH A DEFECTIVE DDR, WITHOUT MOLECULAR ABERRATIONS IN TP53 AND/OR ATM. THESE FINDINGS MAKE THE ATM-P53 RT-MLPA FUNCTIONAL ASSAY A PROMISING PROGNOSTIC TOOL FOR PREDICTING TREATMENT RESPONSES IN CLL. 2015 16 2262 30 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 17 3084 31 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 18 3764 30 INTEGRATIVE ANALYSIS OF DNA METHYLATION AND GENE EXPRESSION DATA IDENTIFIES EPAS1 AS A KEY REGULATOR OF COPD. CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) IS A COMPLEX DISEASE. GENETIC, EPIGENETIC, AND ENVIRONMENTAL FACTORS ARE KNOWN TO CONTRIBUTE TO COPD RISK AND DISEASE PROGRESSION. THEREFORE WE DEVELOPED A SYSTEMATIC APPROACH TO IDENTIFY KEY REGULATORS OF COPD THAT INTEGRATES GENOME-WIDE DNA METHYLATION, GENE EXPRESSION, AND PHENOTYPE DATA IN LUNG TISSUE FROM COPD AND CONTROL SAMPLES. OUR INTEGRATIVE ANALYSIS IDENTIFIED 126 KEY REGULATORS OF COPD. WE IDENTIFIED EPAS1 AS THE ONLY KEY REGULATOR WHOSE DOWNSTREAM GENES SIGNIFICANTLY OVERLAPPED WITH MULTIPLE GENES SETS ASSOCIATED WITH COPD DISEASE SEVERITY. EPAS1 IS DISTINCT IN COMPARISON WITH OTHER KEY REGULATORS IN TERMS OF METHYLATION PROFILE AND DOWNSTREAM TARGET GENES. GENES PREDICTED TO BE REGULATED BY EPAS1 WERE ENRICHED FOR BIOLOGICAL PROCESSES INCLUDING SIGNALING, CELL COMMUNICATIONS, AND SYSTEM DEVELOPMENT. WE CONFIRMED THAT EPAS1 PROTEIN LEVELS ARE LOWER IN HUMAN COPD LUNG TISSUE COMPARED TO NON-DISEASE CONTROLS AND THAT EPAS1 GENE EXPRESSION IS REDUCED IN MICE CHRONICALLY EXPOSED TO CIGARETTE SMOKE. AS EPAS1 DOWNSTREAM GENES WERE SIGNIFICANTLY ENRICHED FOR HYPOXIA RESPONSIVE GENES IN ENDOTHELIAL CELLS, WE TESTED EPAS1 FUNCTION IN HUMAN ENDOTHELIAL CELLS. EPAS1 KNOCKDOWN BY SIRNA IN ENDOTHELIAL CELLS IMPACTED GENES THAT SIGNIFICANTLY OVERLAPPED WITH EPAS1 DOWNSTREAM GENES IN LUNG TISSUE INCLUDING HYPOXIA RESPONSIVE GENES, AND GENES ASSOCIATED WITH EMPHYSEMA SEVERITY. OUR FIRST INTEGRATIVE ANALYSIS OF GENOME-WIDE DNA METHYLATION AND GENE EXPRESSION PROFILES ILLUSTRATES THAT NOT ONLY DOES DNA METHYLATION PLAY A 'CAUSAL' ROLE IN THE MOLECULAR PATHOPHYSIOLOGY OF COPD, BUT IT CAN BE LEVERAGED TO DIRECTLY IDENTIFY NOVEL KEY MEDIATORS OF THIS PATHOPHYSIOLOGY. 2015 19 11 35 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 20 6826 28 [GENOME-WIDE ANALYSIS OF DNA METHYLATION IN CD4+ T LYMPHOCYTES OF PATIENTS WITH PRIMARY PROGRESSIVE MULTIPLE SCLEROSIS INDICATES INVOLVEMENT OF THIS EPIGENETIC PROCESS IN THE DISEASE IMMUNOPATHOGENESIS]. THE PATHOGENESIS OF MULTIPLE SCLEROSIS (MS), A CHRONIC DISEASE OF THE CNS, INCLUDES AUTOIMMUNE AND NEURODEGENERATIVE COMPONENTS. IN MOST CASES, PATIENTS DEVELOP RELAPSING-REMITTING MS (RRMS), WHILE 10-15% OF PATIENTS DEVELOP PRIMARY PROGRESSIVE MS (PPMS), WHICH DIFFERS FROM RRMS IN THE MECHANISMS OF THE PATHOLOGICAL PROCESS, SOME DEMOGRAPHIC, AND SOME CLINICAL CHARACTERISTICS. THESE DIFFERENCES MAY BE EXPLAINED BY THE EPIGENETIC REGULATION OF GENE EXPRESSION IN PPMS INCLUDING DNA METHYLATION AS ONE OF THE KEY EPIGENETIC PROCESSES. THE FEATURES OF DNA METHYLATION IN VARIOUS CELL POPULATIONS IN PPMS PATIENTS REMAIN UNDERSTUDIED. THE GOAL OF THIS STUDY IS TO IDENTIFY DIFFERENTIALLY METHYLATED CPG SITES (DMSS) OF THE GENOME OF CD4+ T LYMPHOCYTES, WHICH CHARACTERIZE PPMS. THE STUDY INCLUDED EIGHT TREATMENT-NAIVE PPMS PATIENTS AND EIGHT HEALTHY CONTROLS. GENOME-WIDE ANALYSIS OF DNA METHYLATION OF CD4+ T LYMPHOCYTES WAS PERFORMED USING HIGH-DENSITY DNA MICROARRAYS. WE HAVE IDENTIFIED 108 DMSS, WHICH DISTINGUISH PPMS PATIENTS FROM HEALTHY CONTROLS. IN PPMS PATIENTS 81% OF THE DMSS ARE HYPERMETHYLATED. MORE THAN A HALF OF THE IDENTIFIED DMSS ARE LOCATED IN KNOWN GENES IN CPG ISLANDS AND ADJACENT REGIONS, WHICH INDICATES A HIGH FUNCTIONAL SIGNIFICANCE OF THESE DMSS IN PPMS DEVELOPMENT. ANALYSIS OF THE OVERREPRESENTATION OF DMS-CONTAINING GENES IN THE MAIN BIOLOGICAL PROCESSES DEMONSTRATES THEIR INVOLVEMENT IN THE REGULATION OF CELL ADHESION TO THE EXTRACELLULAR MATRIX AND THE DEVELOPMENT OF THE IMMUNE RESPONSE, I.E., ANTIGEN PROCESSING AND PRESENTATION, AND DEVELOPMENT OF THE IMMUNE SYSTEM. GENOME-WIDE ANALYSIS OF DNA METHYLATION IN CD4+ T LYMPHOCYTES OF PPMS PATIENTS INDICATES THE INVOLVEMENT OF THIS EPIGENETIC PROCESS IN THE IMMUNOPATHOGENESIS OF THE DISEASE. THESE RESULTS MAY HELP BETTER UNDERSTAND THE PATHOGENESIS OF THIS SEVERE FORM OF MS. 2022