1 5272 172 PROMOTER HYPERMETHYLATION OF THE AE2/SLC4A2 GENE IN PBC. BACKGROUND & AIMS: PATIENTS WITH PRIMARY BILIARY CHOLANGITIS (PBC) EXHIBIT REDUCED AE2/SLC4A2 GENE EXPRESSION IN THE LIVER AND PERIPHERAL BLOOD MONONUCLEAR CELLS (PBMCS). AE2 ENCODES A CL(-)/HCO(3) (-) EXCHANGER INVOLVED IN BILIARY BICARBONATE SECRETION AND INTRACELLULAR PH REGULATION. REDUCED AE2 EXPRESSION IN PBC MAY BE PATHOGENIC, AS AE2-KNOCKOUT MICE REPRODUCE CHARACTERISTIC PBC FEATURES. HEREIN, WE AIMED TO IDENTIFY CPG-METHYLATION ABNORMALITIES IN AE2 PROMOTER REGIONS THAT MIGHT CONTRIBUTE TO THE REDUCED GENE TRANSCRIPTION IN PBC LIVERS AND PBMCS. METHODS: CPG-CYTOSINE METHYLATION RATES WERE INTERROGATED AT 1-BASE PAIR RESOLUTION IN UPSTREAM AND ALTERNATE AE2 PROMOTER REGIONS THROUGH PYROSEQUENCING OF BISULPHITE-MODIFIED GENOMIC DNA FROM LIVER SPECIMENS AND PBMCS. AE2A AND ALTERNATIVE AE2B1 AND AE2B2 MRNA LEVELS WERE MEASURED BY REAL-TIME PCR. HUMAN LYMPHOBLASTOID-T2 CELLS WERE TREATED WITH 5-AZA-2 -DEOXYCYTIDINE FOR DEMETHYLATION ASSAYS. RESULTS: AE2 PROMOTERS WERE FOUND TO BE HYPERMETHYLATED IN PBC LIVERS COMPARED TO NORMAL AND DISEASED LIVER SPECIMENS. RECEIVER OPERATING CHARACTERISTIC (ROC) CURVE ANALYSIS SHOWED THAT MINIMAL CPG-HYPERMETHYLATION CLUSTERS OF 3 AE2A-CPG SITES AND 4 ALTERNATE-AE2B2-CPG SITES SPECIFICALLY DIFFERENTIATED PBC FROM NORMAL AND DISEASED CONTROLS, WITH MEAN METHYLATION RATES INVERSELY CORRELATING WITH RESPECTIVE TRANSCRIPT LEVELS. ADDITIONALLY, IN PBMCS A MINIMAL CLUSTER OF 3 HYPERMETHYLATED AE2A-CPG SITES DISTINGUISHED PBC FROM CONTROLS, AND MEAN METHYLATION RATES CORRELATED NEGATIVELY WITH AE2A MRNA LEVELS IN THESE IMMUNE CELLS. ALTERNATE AE2B2/AE2B1 PROMOTERS IN PBMCS WERE CONSTITUTIVELY HYPERMETHYLATED, IN LINE WITH ABSENT ALTERNATIVE MRNA EXPRESSION IN DISEASED AND HEALTHY PBMCS. DEMETHYLATION ASSAYS TREATING LYMPHOBLASTOID-T2 CELLS WITH 5-AZA-2 -DEOXYCYTIDINE TRIGGERED AE2B2/AE2B1 EXPRESSION AND UPREGULATED AE2A-PROMOTER EXPRESSION. CONCLUSIONS: DISEASE-SPECIFIC HYPERMETHYLATION OF AE2 PROMOTER REGIONS AND SUBSEQUENT DOWNREGULATION OF AE2-GENE EXPRESSION IN THE LIVER AND PBMCS OF PATIENTS WITH PBC MIGHT BE CRITICALLY INVOLVED IN THE PATHOGENESIS OF THIS COMPLEX DISEASE. LAY SUMMARY: PRIMARY BILIARY CHOLANGITIS (PBC) IS A CHRONIC IMMUNE-ASSOCIATED CHOLESTATIC LIVER DISEASE WITH UNCLEAR COMPLEX/MULTIFACTORIAL ETIOPATHOGENESIS AFFECTING MOSTLY MIDDLE-AGED WOMEN. PATIENTS WITH PBC EXHIBIT REDUCED EXPRESSION OF THE AE2/SLC4A2 GENE. HEREIN, WE FOUND THAT AE2 PROMOTER REGIONS ARE HYPERMETHYLATED IN THE LIVER AND PERIPHERAL BLOOD MONONUCLEAR CELLS OF PATIENTS WITH PBC. THIS INCREASED METHYLATION IS ASSOCIATED WITH DOWNREGULATED AE2-GENE EXPRESSION, WHICH MIGHT CONTRIBUTE TO THE PATHOGENESIS OF PBC. THEREFORE, NOVEL EPIGENETIC TARGETS MAY IMPROVE TREATMENT IN PATIENTS WITH PBC WHO RESPOND POORLY TO CURRENT PHARMACOLOGICAL THERAPIES. 2019 2 4221 49 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 3 155 38 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 4 494 40 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 5 3468 52 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 6 3866 43 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 7 3125 30 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 8 4694 40 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 9 546 42 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 10 3296 41 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 11 2453 40 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 12 1966 35 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 13 2753 36 EXPRESSION OF BCL2L12 IN CHRONIC LYMPHOCYTIC LEUKEMIA PATIENTS: ASSOCIATION WITH CLINICAL AND MOLECULAR PROGNOSTIC MARKERS. DYSREGULATION OF APOPTOSIS IS A DISTINCTIVE FEATURE OF CHRONIC LYMPHOCYTIC LEUKEMIA (CLL), ALTHOUGH A UNIQUE MECHANISM UNDERLYING APOPTOSIS RESISTANCE OF CLL B LYMPHOCYTES HAS NOT BEEN IDENTIFIED YET. ABERRANT EXPRESSION AS WELL AS GENETIC AND EPIGENETIC ALTERATIONS OF NUMEROUS GENES INVOLVED IN DIFFERENT PATHWAYS OF APOPTOSIS REGULATION HAS BEEN DESCRIBED IN CLL. HERE, WE REPORT THE EXPRESSION ANALYSIS OF BCL2L12 (BCL2-LIKE 12), A NOVEL APOPTOTIC GENE BELONGING TO BCL2 FAMILY, IN 58 SERBIAN CLL PATIENTS. QUANTITATIVE REVERSE-TRANSCRIPTASE POLYMERASE CHAIN REACTION (QRT-PCR) ANALYSIS REVEALED A SIGNIFICANT OVEREXPRESSION OF BCL2L12 MRNA IN CLL SAMPLES COMPARED TO NON-LEUKEMIC SAMPLES, IMPLYING ITS ROLE IN THE PATHOGENESIS OF THE DISEASE. RECEIVER OPERATING CHARACTERISTIC (ROC) ANALYSIS SHOWED THAT BCL2L12 EXPRESSION EFFICIENTLY DISCRIMINATES CLL CASES FROM HEALTHY CONTROLS. HOWEVER, RELATIVELY HOMOGENOUS BCL2L12 MRNA EXPRESSION AMONG PATIENTS DID NOT REFLECT THEIR CLINICAL CHARACTERISTICS (WITH THE EXCEPTION OF LACTATE DEHYDROGENASE STATUS AND TIME FROM DIAGNOSIS TO TREATMENT) AND FAILED TO SHOW ASSOCIATION WITH THE MOST INFORMATIVE PROGNOSTIC MARKERS, NAMELY THE MUTATIONAL STATUS OF REARRANGED IMMUNOGLOBULIN HEAVY CHAIN VARIABLE REGION GENES, CD38 AND LIPOPROTEIN LIPASE GENE (LPL) EXPRESSION. 2013 14 1081 35 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 15 2262 40 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 2395 36 EPIGENETIC REPROGRAMMING IN MIST1(-/-) MICE PREDICTS THE MOLECULAR RESPONSE TO CERULEIN-INDUCED PANCREATITIS. GENE EXPRESSION IS AFFECTED BY MODIFICATIONS TO HISTONE CORE PROTEINS WITHIN CHROMATIN. CHANGES IN THESE MODIFICATIONS, OR EPIGENETIC REPROGRAMMING, CAN DICTATE CELL FATE AND PROMOTE SUSCEPTIBILITY TO DISEASE. THE GOAL OF THIS STUDY WAS TO DETERMINE THE EXTENT OF EPIGENETIC REPROGRAMMING IN RESPONSE TO CHRONIC STRESS THAT OCCURS FOLLOWING ABLATION OF MIST1 (MIST1(-/-) ), WHICH IS REPRESSED IN PANCREATIC DISEASE. CHROMATIN IMMUNOPRECIPITATION FOR TRIMETHYLATION OF LYSINE RESIDUE 4 ON HISTONE 3 (H3K4ME3) IN PURIFIED ACINAR CELLS FROM WILD TYPE AND MIST1(-/-) MICE WAS FOLLOWED BY NEXT GENERATION SEQUENCING (CHIP-SEQ) OR CHIP-QPCR. H3K4ME3-ENRICHED GENES WERE ASSESSED FOR EXPRESSION BY QRT-PCR IN PANCREATIC TISSUE BEFORE AND AFTER INDUCTION OF CERULEIN-INDUCED PANCREATITIS. WHILE MOST OF H3K4ME3-ENRICHMENT IS RESTRICTED TO TRANSCRIPTIONAL START SITES, >25% OF ENRICHMENT SITES ARE FOUND WITHIN, DOWNSTREAM OR BETWEEN ANNOTATED GENES. LESS THAN 10% OF THESE SITES WERE ALTERED IN MIST1(-/-) ACINI, WITH MOST CHANGES IN H3K4ME3 ENRICHMENT NOT REFLECTING ALTERED GENE EXPRESSION. INGENUITY PATHWAY ANALYSIS OF GENES DIFFERENTIALLY-ENRICHED FOR H3K4ME3 REVEALED AN ASSOCIATION WITH PANCREATITIS AND PANCREATIC DUCTAL ADENOCARCINOMA IN MIST1(-/-) TISSUE. MOST OF THESE GENES WERE NOT DIFFERENTIALLY EXPRESSED BUT SEVERAL WERE READILY INDUCED BY ACUTE EXPERIMENTAL PANCREATITIS, WITH SIGNIFICANTLY INCREASED EXPRESSION IN MIST1(-/-) TISSUE RELATIVE TO WILD TYPE MICE. WE SUGGEST THAT THE CHRONIC CELL STRESS OBSERVED IN THE ABSENCE OF MIST1 RESULTS IN EPIGENETIC REPROGRAMMING OF GENES INVOLVED IN PROMOTING PANCREATITIS TO A POISED STATE, THEREBY INCREASING THE SENSITIVITY TO EVENTS THAT PROMOTE DISEASE. 2014 17 5269 46 PROMOTER DNA METHYLATION CONTRIBUTES TO HUMAN BETA-DEFENSIN-1 DEFICIENCY IN ATOPIC DERMATITIS. ATOPIC DERMATITIS (AD) IS A CHRONIC INFLAMMATORY SKIN DISEASE CAUSED BY EPIDERMAL BARRIER DYSFUNCTION AND DYSREGULATION OF INNATE AND ADAPTIVE IMMUNITY. EPIGENETIC REGULATION OF HUMAN BETA-DEFENSIN-1 (HBD-1) MIGHT BE ASSOCIATED WITH A VARIETY OF DEFECTS IN THE INNATE IMMUNE SYSTEM DURING AD PATHOGENESIS. WE INVESTIGATED THE POSSIBLE MECHANISM OF DECREASED HBD-1 GENE EXPRESSION IN AD AND DEMONSTRATED THE RESTORATION OF HBD-1 TRANSCRIPTION IN UNDIFFERENTIATED NORMAL HUMAN EPIDERMAL KERATINOCYTE CELLS AFTER TREATMENT WITH A DNA METHYLTRANSFERASE INHIBITOR. WE ALSO CONDUCTED AN IN VITRO METHYLATED REPORTER ASSAY USING A REPORTER CONTAINING 14 CPG SITES. METHYLATION OF THE 14 CPG SITES WITHIN THE HBD-1 5' REGION RESULTED IN AN APPROXIMATELY 86% REDUCTION IN PROMOTER ACTIVITY AND AFFECTED HBD-1 TRANSCRIPTIONAL REGULATION. WE THEN COMPARED METHYLATION FREQUENCIES AT CPG 3 AND CPG 4 BETWEEN NON-LESIONAL AND LESIONAL EPIDERMIS SAMPLES OF PATIENTS WITH SEVERE AD AND BETWEEN THESE PAIRED TISSUES AND HEALTHY CONTROL EPIDERMIS FROM NORMAL VOLUNTEERS WITHOUT AD HISTORY. BISULFITE PYROSEQUENCING DATA SHOWED SIGNIFICANTLY HIGHER METHYLATION FREQUENCIES AT THE CPG 3 AND 4 SITES IN AD LESIONAL SAMPLES THAN IN NON-LESIONAL AD SKIN AND NORMAL SKIN SAMPLES (P < 0.05). THESE RESULTS SUGGEST THAT THE DNA METHYLATION SIGNATURE OF HBD-1 IS A NOVEL DIAGNOSTIC/PROGNOSTIC MARKER AND A PROMISING THERAPEUTIC TARGET FOR THE COMPROMISED STRATUM CORNEUM BARRIER ATTRIBUTED TO HBD-1 DEFICIENCY. 2018 18 1144 44 CONCOMITANT HETEROCHROMATINISATION AND DOWN-REGULATION OF GENE EXPRESSION UNVEILS EPIGENETIC SILENCING OF RELB IN AN AGGRESSIVE SUBSET OF CHRONIC LYMPHOCYTIC LEUKEMIA IN MALES. BACKGROUND: THE SENSITIVITY OF CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) CELLS TO CURRENT TREATMENTS, BOTH IN VITRO AND IN VIVO, RELIES ON THEIR ABILITY TO ACTIVATE APOPTOTIC DEATH. CLL CELLS RESISTANT TO DNA DAMAGE-INDUCED APOPTOSIS DISPLAY DEREGULATION OF A SPECIFIC SET OF GENES. METHODS: MICROARRAY HYBRIDIZATION (HUMAN GENECHIP, AFFYMETRIX), IMMUNOFLUORESCENT IN SITU LABELING COUPLED WITH VIDEO-MICROSCOPY RECORDING/ANALYSES, CHROMATIN-IMMUNOPRECIPITATION (CHIP), POLYMERASE CHAIN REACTIONS (PCR), REAL-TIME QUANTITATIVE PCR (RT-QPCR) AND BISULFITE GENOME SEQUENCING WERE THE MAIN METHODS APPLIED. STATISTICAL ANALYSES WERE PERFORMED BY APPLYING GCRMA AND SAM ANALYSIS (MICROARRAY DATA) AND STUDENT'S T-TEST OR MANN & WHITNEY'S U-TEST. RESULTS: HEREIN WE SHOW THAT, REMARKABLY, IN A RESISTANT MALE CLL CELLS THE VAST MAJORITY OF GENES WERE DOWN-REGULATED COMPARED WITH SENSITIVE CELLS, WHEREAS THIS WAS NOT THE CASE IN CELLS DERIVED FROM FEMALES. THIS GENE DOWN-REGULATION WAS FOUND TO BE ASSOCIATED WITH AN OVERALL GAIN OF HETEROCHROMATIN AS EVIDENCED BY IMMUNOFLUORESCENT LABELING OF HETEROCHROMATIN PROTEIN 1ALPHA (HP-1), TRIMETHYLATED HISTONE 3 LYSINE 9 (3METH3K9), AND 5-METHYLCYTIDINE (5METC). NOTABLY, 17 GENES WERE FOUND TO BE COMMONLY DEREGULATED IN RESISTANT MALE AND FEMALE CELL SAMPLES. AMONG THESE, RELB WAS IDENTIFIED AS A DISCRIMINATORY CANDIDATE GENE REPRESSED IN THE MALE AND UPREGULATED IN THE FEMALE RESISTANT CELLS. CONCLUSION: THE MOLECULAR DEFECTS IN THE SILENCING OF RELB INVOLVE AN INCREASE IN H3K9- BUT NOT CPG-ISLAND METHYLATION IN THE PROMOTER REGIONS. INCREASE IN ACETYL-H3 IN RESISTANT FEMALE BUT NOT MALE CLL SAMPLES AS WELL AS A DECREASE OF TOTAL CELLULAR LEVEL OF RELB AFTER AN INHIBITION OF HISTONE DEACETYLASE (HDAC) BY TRICHOSTATIN A (TSA), FURTHER EMPHASIZE THE ROLE OF EPIGENETIC MODIFICATIONS WHICH COULD DISCRIMINATE TWO CLL SUBSETS. TOGETHER, THESE RESULTS HIGHLIGHTED THE EPIGENETIC RELB SILENCING AS A NEW MARKER OF THE PROGRESSIVE DISEASE IN MALES. 2010 19 5275 49 PROMOTER METHYLATION OF THE BONE MORPHOGENETIC PROTEIN-6 GENE IN ASSOCIATION WITH ADULT T-CELL LEUKEMIA. BONE MORPHOGENETIC PROTEINS (BMP), BELONGING TO THE TRANSFORMING GROWTH FACTOR-BETA SUPERFAMILY, ARE MULTIFUNCTIONAL REGULATORS OF CELL PROLIFERATION, DIFFERENTIATION AND APOPTOSIS IN VARIOUS TYPES OF MALIGNANT CELLS. IN THIS STUDY, WE INVESTIGATED BMP-6 PROMOTER METHYLATION IN PATIENTS WITH VARIOUS TYPES OF LEUKEMIAS. THE BMP-6 METHYLATION WAS FOUND PREFERENTIALLY IN ADULT T-CELL LEUKEMIA (ATL) (49 OF 60, 82%) COMPARED WITH OTHER TYPES OF LEUKEMIAS STUDIED INCLUDING ACUTE MYELOID LEUKEMIA (3 OF 67, 5%), ACUTE LYMPHOBLASTIC LEUKEMIA (6 OF 38, 16%) AND CHRONIC LYMPHOCYTIC LEUKEMIA (1 OF 21, 5%). AMONG SUBTYPES OF ATL, THE BMP-6 GENE WAS MORE FREQUENTLY METHYLATED IN AGGRESSIVE ATL FORMS OF ACUTE (96%) AND LYMPHOMA (94%) TYPES THAN LESS MALIGNANT CHRONIC ATL (44%) AND SMOLDERING ATL (20%). WE ALSO ANALYZED THE METHYLATION STATUS OF PERIPHERAL BLOOD MONONUCLEAR CELLS FROM HEALTHY DONORS AND NONMALIGNANT LYMPH NODES WITH REACTIVE LYMPHADENOPATHY, NONE OF WHICH SHOWED DETECTABLE BMP-6 METHYLATION IN THIS STUDY. THE BMP-6 METHYALTION WAS CORRELATED WITH DECREASED MRNA TRANSCRIPT AND PROTEIN EXPRESSION. EXPRESSION OF BMP-6 WAS RESTORED BY THE DEMETHYLATING AGENT 5-AZA-2'-DEOXYCYTIDINE, SUGGESTING THAT METHYLATION WAS ASSOCIATED WITH THE TRANSCRIPTIONAL SILENCING. SERIAL ANALYSIS DEMONSTRATED AN INCREASING METHYLATION OF CPG SITES IN THE BMP-6 PROMOTER AND THE RESULTANT SUPPRESSION OF BMP-6 EXPRESSION AS ATL PROGRESSED. THESE FINDINGS SUGGESTED THAT BMP-6 PROMOTER METHYLATION IS LIKELY TO BE A COMMON EPIGENETIC EVENT AT LATER STAGES OF ATL AND THAT THE METHYLATION PROFILES MAY BE USEFUL FOR THE STAGING OF ATL AS WELL AS FOR EVALUATION OF THE INDIVIDUAL RISK OF DEVELOPING THE DISEASE. 2008 20 1598 35 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