1 1456 160 DISCRIMINATING THE MOLECULAR BASIS OF HEPATOTOXICITY USING THE LARGE-SCALE CHARACTERISTIC MOLECULAR SIGNATURES OF TOXICANTS BY EXPRESSION PROFILING ANALYSIS. PREDICTING THE POTENTIAL HUMAN HEALTH RISK POSED BY CHEMICAL STRESSORS HAS LONG BEEN A MAJOR CHALLENGE FOR TOXICOLOGISTS, AND THE USE OF MICROARRAYS TO MEASURE RESPONSES TO TOXICOLOGICALLY RELEVANT GENES, AND TO IDENTIFY SELECTIVE, SENSITIVE BIOMARKERS OF TOXICITY IS A MAJOR APPLICATION OF PREDICTIVE AND DISCOVERY TOXICOLOGY. TO INVESTIGATE THIS POSSIBILITY, WE INVESTIGATED WHETHER CARCINOGENS (AT DOSES KNOWN TO INDUCE LIVER TUMORS IN CHRONIC EXPOSURE BIOASSAYS) DEREGULATE CHARACTERISTIC SETS OF GENES IN MICE. MALE C3H/HE MICE WERE DOSED WITH TWO HEPATOCARCINOGENS (VINYL CHLORIDE (VC, 50-25 MG/KG), ALDRIN (AD, 0.8-0.4 MG/KG)), OR TWO NON-HEPATOCARCINOGENS (COPPER SULFATE (CS, 150-60 MG/KG), 2,4,5-TRICHLOROPHENOXYACETIC ACID (2,4,5-T, 150-60 MG/KG)). LARGE-SCALE MOLECULAR CHANGES ELICITED BY THESE FOUR HEPATOTOXICANTS IN LIVER TISSUES WERE ANALYZED USING DNA MICROARRAY. THREE DAYS AFTER ADMINISTRATION, NO SIGNIFICANT PHENOTYPIC CHANGES WERE INDUCED BY THESE FOUR DIFFERENT HEPATOTOXICANTS IN TERMS OF HISTOLOGICAL EXAMINATION OR BLOOD BIOCHEMICAL ASSAY. HOWEVER, UNSUPERVISED HIERARCHICAL ANALYSIS OF GENE EXPRESSIONAL CHANGES INDUCED BY HEPATOTOXICANTS RESULTED IN TWO MAJOR GENE SUBCLUSTERS ON DENDROGRAM, I.E., A CARCINOGEN (VN, AD) AND NON-CARCINOGEN GROUP (CS, 2,4,5-T), AND ALSO REVEALED THAT DISTINCT MOLECULAR SIGNATURES EXIST. THESE SIGNATURES WERE FOUNDED ON WELL-DEFINED FUNCTIONAL GENE CATEGORIES AND MAY DIFFERENTIATE GENOTOXIC AND NON-GENOTOXIC CARCINOGENS. FURTHERMORE, VENN DIAGRAM ANALYSIS ALLOWED US TO IDENTIFY CARCINOGEN AND NON-CARCINOGEN-ASSOCIATED MOLECULAR SIGNATURES. USING STATISTICAL METHODS, WE ANALYZED OUTLIER GENES FOR FOUR DIFFERENT CLASSES (GENOTOXIC-, NON-GENOTOXIC-CARCINOGEN, GENOTOXIC-, NON-GENOTOXIC NON-CARCINOGEN) IN TERMS OF THEIR POTENTIAL TO PREDICT DIFFERENT MODES-OF-ACTION. IN CONCLUSION, THE IDENTIFICATION OF LARGE-SCALE MOLECULAR CHANGES IN DIFFERENT HEPATOCARCINOGEN EXPOSURE MODELS REVEALED THAT DIFFERENT TYPES OF HEPATOTOXICANTS ARE ASSOCIATED WITH DIFFERENT EPIGENETIC CHANGES AND MOLECULAR PATHWAYS AND THAT THESE LARGE-SCALE CHARACTERISTIC MOLECULAR CHANGES COULD BE USED AS PREDICTABLE TOXICITY MARKERS. 2008 2 4517 31 MULTI-OMICS FACTOR ANALYSIS-A FRAMEWORK FOR UNSUPERVISED INTEGRATION OF MULTI-OMICS DATA SETS. MULTI-OMICS STUDIES PROMISE THE IMPROVED CHARACTERIZATION OF BIOLOGICAL PROCESSES ACROSS MOLECULAR LAYERS. HOWEVER, METHODS FOR THE UNSUPERVISED INTEGRATION OF THE RESULTING HETEROGENEOUS DATA SETS ARE LACKING. WE PRESENT MULTI-OMICS FACTOR ANALYSIS (MOFA), A COMPUTATIONAL METHOD FOR DISCOVERING THE PRINCIPAL SOURCES OF VARIATION IN MULTI-OMICS DATA SETS. MOFA INFERS A SET OF (HIDDEN) FACTORS THAT CAPTURE BIOLOGICAL AND TECHNICAL SOURCES OF VARIABILITY. IT DISENTANGLES AXES OF HETEROGENEITY THAT ARE SHARED ACROSS MULTIPLE MODALITIES AND THOSE SPECIFIC TO INDIVIDUAL DATA MODALITIES. THE LEARNT FACTORS ENABLE A VARIETY OF DOWNSTREAM ANALYSES, INCLUDING IDENTIFICATION OF SAMPLE SUBGROUPS, DATA IMPUTATION AND THE DETECTION OF OUTLIER SAMPLES. WE APPLIED MOFA TO A COHORT OF 200 PATIENT SAMPLES OF CHRONIC LYMPHOCYTIC LEUKAEMIA, PROFILED FOR SOMATIC MUTATIONS, RNA EXPRESSION, DNA METHYLATION AND EX VIVO DRUG RESPONSES. MOFA IDENTIFIED MAJOR DIMENSIONS OF DISEASE HETEROGENEITY, INCLUDING IMMUNOGLOBULIN HEAVY-CHAIN VARIABLE REGION STATUS, TRISOMY OF CHROMOSOME 12 AND PREVIOUSLY UNDERAPPRECIATED DRIVERS, SUCH AS RESPONSE TO OXIDATIVE STRESS. IN A SECOND APPLICATION, WE USED MOFA TO ANALYSE SINGLE-CELL MULTI-OMICS DATA, IDENTIFYING COORDINATED TRANSCRIPTIONAL AND EPIGENETIC CHANGES ALONG CELL DIFFERENTIATION. 2018 3 3413 39 HSA-MIR-29C AND HSA-MIR-135B DIFFERENTIAL EXPRESSION AS POTENTIAL BIOMARKER OF GASTRIC CARCINOGENESIS. AIM: TO INVESTIGATE THE EXPRESSION PROFILES OF HSA-MIR-29C AND HSA-MIR-135B IN GASTRIC MUCOSAL SAMPLES AND THEIR VALUES AS GASTRIC CARCINOGENESIS BIOMARKERS. METHODS: THE EXPRESSION LEVELS OF HSA-MIR-29C AND HSA-MIR-135B IN NORMAL GASTRIC MUCOSA, NON-ATROPHIC CHRONIC GASTRITIS, INTESTINAL METAPLASIA AND INTESTINAL-TYPE GASTRIC ADENOCARCINOMA WERE ANALYSED USING QUANTITATIVE REAL-TIME PCR. THE DIFFERENCE BETWEEN HSA-MIR-29C AND HSA-MIR-135B EXPRESSION PROFILES IN THE GROUPED SAMPLES WAS EVALUATED BY ANOVA AND STUDENT'S T-TEST TESTS. THE RESULTS WERE ADJUSTED FOR MULTIPLE TESTING BY USING BONFERRONI'S CORRECTION. P VALUES 2 AND FDR < 0.05 AFTER MULTIPLE TEST CORRECTIONS. RESULTS: IN TOTAL, WE IDENTIFIED 130 CD SPECIFIC DE NCRNAS (89 IN ILEUM AND 41 IN RECTUM) WHEN COMPARED TO NON-IBD CONTROLS. SIMILARLY, 35 DE NCRNAS WERE IDENTIFIED BETWEEN B1 AND B2 IN ILEUM, WHEREAS NO DIFFERENCES AMONG CD DISEASE BEHAVIORS WERE NOTICED IN RECTUM. WE ALSO FOUND INFLAMMATION SPECIFIC NCRNAS BETWEEN INFLAMED AND NON-INFLAMED GROUPS IN ILEAL BIOPSIES. OVERALL, WE OBSERVED THAT EXPRESSION OF MIR1244-2, MIR1244-3, MIR1244-4, AND RN7SL2 WERE INCREASED DURING CD, REGARDLESS OF DISEASE BEHAVIOR, LOCATION, OR INFLAMMATORY STATUS. LASTLY, WE TESTED NCRNA EXPRESSION AT BASELINE AS POTENTIAL TOOL TO PREDICT THE DISEASE STATUS, DISEASE BEHAVIORS AND DISEASE INFLAMMATION AT 3-YEAR FOLLOW UP. CONCLUSIONS: WE HAVE IDENTIFIED NCRNAS THAT ARE SPECIFIC TO DISEASE LOCATION, DISEASE BEHAVIOR, AND DISEASE INFLAMMATION IN CD. BOTH ILEAL AND RECTAL SPECIFIC NCRNA ARE CHANGING OVER THE COURSE OF CD, SPECIFICALLY DURING THE DISEASE PROGRESSION IN THE INTESTINAL MUCOSA. COLLECTIVELY, OUR FINDINGS SHOW CHANGES IN NCRNA DURING CD AND MAY HAVE A CLINICAL UTILITY IN EARLY IDENTIFICATION AND CHARACTERIZATION OF DISEASE PROGRESSION. 2021 9 3767 36 INTEGRATIVE EPIGENOMIC ANALYSIS IN DIFFERENTIATED HUMAN PRIMARY BRONCHIAL EPITHELIAL CELLS EXPOSED TO CIGARETTE SMOKE. CIGARETTE SMOKE (CS) IS ONE OF THE MAJOR RISK FACTORS FOR MANY PULMONARY DISEASES, INCLUDING CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) AND LUNG CANCER. THE FIRST LINE OF DEFENSE FOR CS EXPOSURE IS THE BRONCHIAL EPITHELIAL CELLS. ELUCIDATION OF THE EPIGENETIC CHANGES DURING CS EXPOSURE IS KEY TO GAINING A MECHANISTIC UNDERSTANDING INTO HOW MATURE AND DIFFERENTIATED BRONCHIAL EPITHELIAL CELLS RESPOND TO CS. THEREFORE, WE PERFORMED EPIGENOMIC PROFILING IN CONJUNCTION WITH TRANSCRIPTIONAL PROFILING IN WELL-DIFFERENTIATED HUMAN BRONCHIAL EPITHELIAL (HBE) CELLS CULTURED IN AIR-LIQUID INTERFACE (ALI) EXPOSED TO THE VAPOR PHASE OF CS. THE GENOME-WIDE ENRICHMENT OF HISTONE 3 LYSINE 27 ACETYLATION WAS DETECTED BY CHROMATIN IMMUNOPRECIPITATION FOLLOWED BY NEXT GENERATION SEQUENCING (CHIP-SEQ) IN HBE CELLS AND SUGGESTED THE PLAUSIBLE BINDING OF SPECIFIC TRANSCRIPTION FACTORS RELATED TO CS EXPOSURE. ADDITIONALLY, INTERROGATION OF CHIP-SEQ DATA WITH GENE EXPRESSION PROFILING OF HBE CELLS AFTER CS EXPOSURE FOR DIFFERENT DURATIONS (3 HOURS, 2 DAYS, 4 DAYS) SUGGESTED THAT EARLIER EPIGENETIC CHANGES (3 HOURS AFTER CS EXPOSURE) MAY BE ASSOCIATED WITH LATER GENE EXPRESSION CHANGES INDUCED BY CS EXPOSURE (4 DAYS). THE INTEGRATION OF EPIGENETICS AND GENE EXPRESSION DATA REVEALED SIGNALING PATHWAYS RELATED TO CS-INDUCED EPIGENETIC CHANGES IN HBE CELLS THAT MAY IDENTIFY NOVEL REGULATORY PATHWAYS RELATED TO CS-INDUCED COPD. 2018 10 972 30 CHRONIC OBSTRUCTIVE PULMONARY DISEASE IS ASSOCIATED WITH EPIGENOME-WIDE DIFFERENTIAL METHYLATION IN BAL LUNG CELLS. DNA METHYLATION PATTERNS IN CHRONIC PULMONARY OBSTRUCTIVE DISEASE (COPD) MIGHT OFFER NEW INSIGHTS INTO DISEASE PATHOGENESIS. TO ASSESS METHYLATION PROFILES IN THE MAIN COPD TARGET ORGAN, WE PERFORMED AN EPIGENOME-WIDE ASSOCIATION STUDY ON BAL CELLS. BRONCHOSCOPIES WERE PERFORMED IN 18 SUBJECTS WITH COPD AND 15 CONTROL SUBJECTS (EX- AND CURRENT SMOKERS). DNA METHYLATION WAS MEASURED USING THE ILLUMINA METHYLATIONEPIC BEADCHIP KIT, COVERING MORE THAN 850,000 CPGS. DIFFERENTIALLY METHYLATED POSITIONS (DMPS) WERE EXAMINED FOR 1) ENRICHMENT IN PATHWAYS AND FUNCTIONAL GENE RELATIONSHIPS USING THE KYOTO ENCYCLOPEDIA OF GENES AND GENOMES AND GENE ONTOLOGY, 2) ACCELERATED AGING USING HORVATH'S EPIGENETIC CLOCK, 3) CORRELATION WITH GENE EXPRESSION, AND 4) COLOCALIZATION WITH GENETIC VARIATION. WE FOUND 1,155 BONFERRONI-SIGNIFICANT (P < 6.74 X 10(-8)) DMPS ASSOCIATED WITH COPD, MANY WITH LARGE EFFECT SIZES. FUNCTIONAL ANALYSIS IDENTIFIED BIOLOGICALLY PLAUSIBLE PATHWAYS AND GENE RELATIONSHIPS, INCLUDING ENRICHMENT FOR TRANSCRIPTION FACTOR ACTIVITY. STRONG CORRELATION WAS FOUND BETWEEN DNA METHYLATION AND CHRONOLOGICAL AGE BUT NOT BETWEEN COPD AND ACCELERATED AGING. FOR 79 UNIQUE DMPS, DNA METHYLATION CORRELATED SIGNIFICANTLY WITH GENE EXPRESSION IN BAL CELLS. THIRTY-NINE PERCENT OF DMPS WERE COLOCALIZED WITH COPD-ASSOCIATED SNPS. TO THE BEST OF OUR KNOWLEDGE, THIS IS THE FIRST EPIGENOME-WIDE ASSOCIATION STUDY OF COPD ON BAL CELLS, AND OUR ANALYSES REVEALED MANY DIFFERENTIAL METHYLATION SITES. INTEGRATION WITH MRNA DATA SHOWED A STRONG FUNCTIONAL READOUT FOR RELEVANT GENES, IDENTIFYING SITES WHERE DNA METHYLATION MIGHT DIRECTLY AFFECT EXPRESSION. ALMOST HALF OF DMPS WERE COLOCATED WITH SNPS IDENTIFIED IN PREVIOUS GENOME-WIDE ASSOCIATION STUDIES OF COPD, SUGGESTING JOINT GENETIC AND EPIGENETIC PATHWAYS RELATED TO DISEASE. 2022 11 2639 30 EPIGENOMIC ANALYSIS DETECTS WIDESPREAD GENE-BODY DNA HYPOMETHYLATION IN CHRONIC LYMPHOCYTIC LEUKEMIA. WE HAVE EXTENSIVELY CHARACTERIZED THE DNA METHYLOMES OF 139 PATIENTS WITH CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) WITH MUTATED OR UNMUTATED IGHV AND OF SEVERAL MATURE B-CELL SUBPOPULATIONS THROUGH THE USE OF WHOLE-GENOME BISULFITE SEQUENCING AND HIGH-DENSITY MICROARRAYS. THE TWO MOLECULAR SUBTYPES OF CLL HAVE DIFFERING DNA METHYLOMES THAT SEEM TO REPRESENT EPIGENETIC IMPRINTS FROM DISTINCT NORMAL B-CELL SUBPOPULATIONS. DNA HYPOMETHYLATION IN THE GENE BODY, TARGETING MOSTLY ENHANCER SITES, WAS THE MOST FREQUENT DIFFERENCE BETWEEN NAIVE AND MEMORY B CELLS AND BETWEEN THE TWO MOLECULAR SUBTYPES OF CLL AND NORMAL B CELLS. ALTHOUGH DNA METHYLATION AND GENE EXPRESSION WERE POORLY CORRELATED, WE IDENTIFIED GENE-BODY CPG DINUCLEOTIDES WHOSE METHYLATION WAS POSITIVELY OR NEGATIVELY ASSOCIATED WITH EXPRESSION. WE HAVE ALSO RECOGNIZED A DNA METHYLATION SIGNATURE THAT DISTINGUISHES NEW CLINICO-BIOLOGICAL SUBTYPES OF CLL. WE PROPOSE AN EPIGENOMIC SCENARIO IN WHICH DIFFERENTIAL METHYLATION IN THE GENE BODY MAY HAVE FUNCTIONAL AND CLINICAL IMPLICATIONS IN LEUKEMOGENESIS. 2012 12 1620 36 DNA METHYLTRANSFERASE-MEDIATED TRANSCRIPTIONAL SILENCING IN MALIGNANT GLIOMA: A COMBINED WHOLE-GENOME MICROARRAY AND PROMOTER ARRAY ANALYSIS. EPIGENETIC INACTIVATION OF TUMOR SUPPRESSOR GENES IS A COMMON FEATURE IN HUMAN CANCER. PROMOTER HYPERMETHYLATION AND HISTONE DEACETYLATION ARE REVERSIBLE EPIGENETIC MECHANISMS ASSOCIATED WITH TRANSCRIPTIONAL REGULATION. DNA METHYLTRANSFERASES (DNMT1 AND DNMT3B) REGULATE AND MAINTAIN PROMOTER METHYLATION AND ARE OVEREXPRESSED IN HUMAN CANCER. WE PERFORMED WHOLE-GENOME MICROARRAY ANALYSIS TO IDENTIFY GENES WITH ALTERED EXPRESSION AFTER RNAI-INDUCED SUPPRESSION OF DNMT IN A GLIOBLASTOMA MULTIFORME (GBM) CELL LINE. WE THEN IDENTIFIED GENES WITH BOTH DECREASED EXPRESSION AND EVIDENCE OF PROMOTER CPG ISLAND HYPERMETHYLATION IN GBM TISSUE SAMPLES USING A COMBINED WHOLE-GENOME MICROARRAY TRANSCRIPTOME ANALYSIS IN CONJUNCTION WITH A PROMOTER ARRAY ANALYSIS AFTER DNA IMMUNOPRECIPITATION WITH ANTI-5-METHYLCYTIDINE. DNMT1 AND 3B KNOCKDOWN RESULTED IN THE RESTORED EXPRESSION OF 308 GENES THAT ALSO CONTAINED PROMOTER REGION HYPERMETHYLATION. OF THESE, 43 WERE ALSO FOUND TO BE DOWNREGULATED IN GBM TISSUE SAMPLES. THREE DOWNREGULATED GENES WITH HYPERMETHYLATED PROMOTERS AND RESTORED EXPRESSION IN RESPONSE TO ACUTE DNMT SUPPRESSION WERE ASSAYED FOR METHYLATION CHANGES USING BISULFITE SEQUENCE ANALYSIS OF THE PROMOTER REGION AFTER CHRONIC DNMT SUPPRESSION. RESTORATION OF GENE EXPRESSION WAS NOT ASSOCIATED WITH CHANGES IN PROMOTER REGION METHYLATION, BUT RATHER WITH CHANGES IN HISTONE METHYLATION AND CHROMATIN CONFORMATION. TWO OF THE IDENTIFIED GENES EXHIBITED GROWTH SUPPRESSIVE ACTIVITY IN IN VITRO ASSAYS. COMBINING TARGETED GENETIC MANIPULATIONS WITH COMPREHENSIVE GENOMIC AND EXPRESSION ANALYSES PROVIDES A POTENTIALLY POWERFUL NEW APPROACH FOR IDENTIFYING EPIGENETICALLY REGULATED GENES IN GBM. 2009 13 2439 35 EPIGENETIC SILENCING OF THE MLH1 PROMOTER IN RELATION TO THE DEVELOPMENT OF GASTRIC CANCER AND ITS USE AS A BIOMARKER FOR PATIENTS WITH MICROSATELLITE INSTABILITY: A SYSTEMATIC ANALYSIS. BACKGROUND/AIMS: HUMAN MUTL HOMOLOG 1 (MLH1) PROMOTER METHYLATION WAS REPORTED IN GASTRIC CANCER (GC). THIS STUDY DETERMINED THE CLINICOPATHOLOGICAL, PROGNOSTIC, AND DIAGNOSTIC EFFECTS OF MLH1 PROMOTER METHYLATION IN GC. METHODS: THE COMBINED ODDS RATIO (OR) OR HAZARD RATIO (HR) AND THEIR CORRESPONDING 95% CONFIDENCE INTERVALS (95% CI) WERE CALCULATED. THE POOLED SENSITIVITY, SPECIFICITY, AND AREA UNDER THE CURVE (AUC) WERE ANALYZED. RESULTS: A TOTAL OF 4654 GC PATIENTS AND 3669 NON-MALIGNANT CONTROLS WERE IDENTIFIED IN THIS SYSTEMATIC ANALYSIS. MLH1 PROMOTER METHYLATION WAS SIGNIFICANTLY HIGHER IN GC SAMPLES THAN IN GASTRIC ADENOMAS, CHRONIC GASTRITIS, ADJACENT TISSUES, NORMAL GASTRIC MUCOSA, AND NORMAL HEALTHY BLOOD SAMPLES, BUT IT EXHIBITED A SIMILAR FREQUENCY IN GC VS. INTESTINAL METAPLASIA AND DYSPLASIA SAMPLES. MLH1 PROMOTER METHYLATION CORRELATED WITH AGE AND MICROSATELLITE INSTABILITY (MSI), BUT IT WAS NOT ASSOCIATED WITH GENDER, H. PYLORI INFECTION, SMOKING, DRINKING BEHAVIORS, PATHOLOGICAL HISTOLOGY, TUMOR DIFFERENTIATION, CLINICAL STAGE, LYMPH NODE STATUS, DISTANT METASTASIS, OR OVERALL SURVIVAL OF GC. MLH1 PROMOTER METHYLATION EXHIBITED A POOR SENSITIVITY VALUE (< 0.5) IN PATIENTS WITH GC COMPARED WITH ADJACENT TISSUES, GASTRIC ADENOMAS, CHRONIC GASTRITIS, NORMAL GASTRIC MUCOSA, AND NORMAL HEALTHY BLOOD SAMPLES. THE POOLED SENSITIVITY, SPECIFICITY, AND AUC OF MLH1 PROMOTER METHYLATION IN GC WITH MSI VS. GC WITH MICROSATELLITE STABILITY (MSS) SAMPLES WERE 0.64, 0.96, AND 0.90, RESPECTIVELY. CONCLUSIONS: OUR RESULTS SUGGEST THAT THE DETECTION OF MLH1 PROMOTER METHYLATION MAY BE A POTENTIAL PROGNOSTIC BIOMARKER FOR GC PATIENTS WITH MSI. 2018 14 5435 29 RELATIVE ROLE OF METHYLATOR AND TUMOR SUPPRESSOR PATHWAYS IN ULCERATIVE COLITIS-ASSOCIATED COLON CANCER. BACKGROUND: CHRONIC ULCERATIVE COLITIS (UC) IS ASSOCIATED WITH AN INCREASED COLORECTAL CANCER RISK WHICH MAY BE SECONDARY TO REPETITIVE MUCOSAL INJURY. BOTH EPIGENETIC METHYLATION AND THE CLASSIC ADENOMA-TO-CARCINOMA SEQUENCE HAVE BEEN IMPLICATED IN THIS MALIGNANT TRANSFORMATION, BUT THE UNDERLYING MOLECULAR MECHANISMS REMAIN POORLY DEFINED. THIS STUDY COMPARES THE MOLECULAR CHARACTERISTICS OF COLITIS-ASSOCIATED AND COMMON COLORECTAL CANCERS. METHODS: NINETEEN PATIENTS WITH COLORECTAL ADENOCARCINOMAS ARISING WITHIN UC WERE MATCHED FOR AGE AND CANCER SITE WITH 54 PATIENTS WITH SPORADIC ADENOCARCINOMAS. TUMOR TISSUE WAS EXAMINED FOR BRAF MUTATIONS, CPG ISLAND METHYLATOR PHENOTYPE (CIMP), AND MLH1 PROMOTER METHYLATION. MUTATIONS OF KRAS AND P53 WERE ASSESSED BY SEQUENCING. RESULTS: PATIENT DEMOGRAPHICS WERE SIMILAR FOR THE TWO GROUPS. CIMP WAS OBSERVED IN 22% OF SPORADIC COLORECTAL CANCERS AND IN 5% OF UC CANCERS (P = 0.162). RATES OF BRAF MUTATION (4% VS 5%, P = 1.0), MLH1 METHYLATION (9% VERSUS 5%, P = 0.682), AND KRAS MUTATIONS (24% VERSUS 32%, P = 0.552) WERE SIMILAR BETWEEN THE GROUPS. HOWEVER, COLITIS-ASSOCIATED COLORECTAL CANCERS WERE MORE LIKELY TO HAVE A P53 MUTATION COMPARED TO SPORADIC ADENOCARCINOMAS (95% VERSUS 53%, P = 0.001). THE DOMINANT MUTATION FOR COLITIS-ASSOCIATED CANCERS WAS A MUTATION IN CODON 4, REPRESENTING HALF OF THE MUTATIONS. FURTHERMORE, COLITIS-ASSOCIATED CANCERS HAD A HIGHER RATE OF MUTATION IN CODON 8 (48% VERSUS 6%, P < 0.001) THAN SPORADIC COUNTERPARTS. CONCLUSIONS: UNLIKE OTHER INFLAMMATORY GASTROINTESTINAL CANCERS, COLITIS-ASSOCIATED COLORECTAL CANCERS DO NOT PREFERENTIALLY ARISE VIA A METHYLATOR PATHWAY WHEN COMPARED TO SPORADIC COLORECTAL CANCERS. CHROMOSOMAL INSTABILITY REMAINS AN IMPORTANT ETIOLOGY, BUT WITH A UNIQUE P53 FREQUENCY AND MUTATION PATTERN. 2011 15 414 31 ANALYSIS OF PROMOTER METHYLATION IN STOOL: A NOVEL METHOD FOR THE DETECTION OF COLORECTAL CANCER. BACKGROUND & AIMS: DETECTION OF TUMOR-DERIVED DNA ALTERATIONS IN STOOL IS AN INTRIGUING NEW APPROACH WITH HIGH POTENTIAL FOR THE NONINVASIVE DETECTION OF COLORECTAL CANCER (CRC). BECAUSE OF HETEROGENEITY OF TUMORS, USUALLY MULTIPLE MARKERS DISTRIBUTED THROUGHOUT THE HUMAN GENOME NEED TO BE ANALYZED. THIS IS LABOR INTENSIVE AND DOES NOT ALLOW FOR HIGH THROUGH-PUT SCREENING. THEREFORE, MARKERS WITH HIGH SENSITIVITY AND GOOD SPECIFICITY ARE NEEDED. WE EXPLORED THE POTENTIAL OF A SINGLE EPIGENETIC MARKER IN COMPARISON WITH FECAL OCCULT BLOOD TESTING (FOBT) FOR THE DISCRIMINATION OF PATIENTS WITH CRCS AND ADENOMAS FROM THOSE WITHOUT. METHODS: METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION (PCR) WAS PERFORMED TO ANALYZE HYPERMETHYLATED IN CANCER 1 (HIC1) PROMOTER METHYLATION STATUS IN A BLINDED FASHION IN STOOL SAMPLES FROM 26 PATIENTS WITH CRC, 13 WITH ADENOMA > OR =1 CM, 9 WITH HYPERPLASTIC POLYPS, 9 WITH CHRONIC INFLAMMATORY BOWEL DISEASE, AND 32 WITH ENDOSCOPICALLY NORMAL COLON. RESULTS: NINETY-SEVEN PERCENT OF THE STOOL SAMPLES CONTAINED AMPLIFIABLE DNA. FORTY-TWO PERCENT OF THE SAMPLES FROM PATIENTS WITH CRC AND 31% OF THE SAMPLES FROM PATIENTS WITH COLORECTAL ADENOMA > OR =1 CM WERE POSITIVE FOR HIC1 PROMOTER METHYLATION. NO METHYLATED HIC1 PROMOTER DNA WAS DETECTED IN THE FECAL DNA FROM PATIENTS WITH ENDOSCOPICALLY NORMAL COLON OR HYPERPLASTIC POLYPS. CONCLUSIONS: THE EPIGENETIC MARKER HIC1 PROMOTER METHYLATION CARRIES HIGH POTENTIAL FOR THE REMOTE DETECTION OF CRCS. WE POSTULATE THAT A PANEL OF MERELY A FEW GENETIC AND EPIGENETIC MARKERS WILL BE REQUIRED FOR THE HIGHLY SENSITIVE AND SPECIFIC DETECTION OF CRCS AND ADENOMAS IN FECAL SAMPLES FROM AFFECTED PATIENTS. 2005 16 1577 35 DNA METHYLATION PROFILE IN CHRONIC MYELOMONOCYTIC LEUKEMIA ASSOCIATES WITH DISTINCT CLINICAL, BIOLOGICAL AND GENETIC FEATURES. CHROMOSOMAL ABNORMALITIES ARE DETECTED IN 20-30% OF PATIENTS WITH CHRONIC MYELOMONOCYTIC LEUKEMIA (CMML) AND CORRELATE WITH PROGNOSIS. ON THE MUTATION LEVEL, DISRUPTIVE ALTERATIONS ARE PARTICULARLY FREQUENT IN CHROMATIN REGULATORY GENES. HOWEVER, LITTLE IS KNOWN ABOUT THE CONSEQUENTIAL ALTERATIONS IN THE EPIGENETIC MARKING OF THE GENOME. HERE, WE REPORT THE ANALYSIS OF GENOMIC DNA METHYLATION PATTERNS OF 64 CMML PATIENTS AND 10 HEALTHY CONTROLS, USING A DNA METHYLATION MICROARRAY FOCUSED ON PROMOTER REGIONS. DIFFERENTIAL METHYLATION ANALYSIS BETWEEN PATIENTS AND CONTROLS ALLOWED US TO IDENTIFY ABNORMALITIES IN DNA METHYLATION, INCLUDING HYPERMETHYLATION OF SPECIFIC GENES AND LARGE GENOME REGIONS WITH ABERRANT DNA METHYLATION. UNSUPERVISED HIERARCHICAL CLUSTER ANALYSIS IDENTIFIED TWO MAIN CLUSTERS THAT ASSOCIATED WITH THE CLINICAL, BIOLOGICAL, AND GENETIC FEATURES OF PATIENTS. GROUP 1 WAS ENRICHED IN PATIENTS WITH ADVERSE CLINICAL AND BIOLOGICAL CHARACTERISTICS AND POORER OVERALL AND PROGRESSION-FREE SURVIVAL. IN ADDITION, SIGNIFICANT DIFFERENCES IN DNA METHYLATION WERE OBSERVED BETWEEN PATIENTS WITH LOW RISK AND INTERMEDIATE/HIGH RISK KARYOTYPES AND BETWEEN TET2 MUTANT AND WILD TYPE PATIENTS. TAKEN TOGETHER, OUR RESULTS DEMONSTRATE THAT ALTERED DNA METHYLATION PATTERNS REFLECT THE CMML DISEASE STATE AND ALLOW TO IDENTIFY PATIENT GROUPS WITH DISTINCT CLINICAL FEATURES. 2018 17 502 42 ASSOCIATION OF ARSENIC EXPOSURE WITH WHOLE BLOOD DNA METHYLATION: AN EPIGENOME-WIDE STUDY OF BANGLADESHI ADULTS. BACKGROUND: ARSENIC EXPOSURE AFFECTS [FORMULA: SEE TEXT] PEOPLE WORLDWIDE, INCLUDING [FORMULA: SEE TEXT] IN BANGLADESH. ARSENIC EXPOSURE INCREASES THE RISK OF CANCER AND OTHER CHRONIC DISEASES, AND ONE POTENTIAL MECHANISM OF ARSENIC TOXICITY IS EPIGENETIC DYSREGULATION. OBJECTIVE: WE ASSESSED ASSOCIATIONS BETWEEN ARSENIC EXPOSURE AND GENOME-WIDE DNA METHYLATION MEASURED AT BASELINE AMONG 396 BANGLADESHI ADULTS PARTICIPATING IN THE HEALTH EFFECTS OF ARSENIC LONGITUDINAL STUDY (HEALS) WHO WERE EXPOSED BY DRINKING NATURALLY CONTAMINATED WELL WATER. METHODS: METHYLATION IN WHOLE BLOOD DNA WAS MEASURED AT [FORMULA: SEE TEXT] USING THE ILLUMINA INFINIUMMETHYLATIONEPIC (EPIC) ARRAY. TO ASSESS ASSOCIATIONS BETWEEN ARSENIC EXPOSURE AND CPG METHYLATION, WE USED LINEAR REGRESSION MODELS ADJUSTED FOR COVARIATES AND SURROGATE VARIABLES (SVS) (CAPTURING UNKNOWN TECHNICAL AND BIOLOGIC FACTORS). WE ATTEMPTED REPLICATION AND CONDUCTED A META-ANALYSIS USING AN INDEPENDENT DATASET OF [FORMULA: SEE TEXT] FROM 400 BANGLADESHI INDIVIDUALS WITH ARSENICAL SKIN LESIONS. RESULTS: WE IDENTIFIED 34 CPGS ASSOCIATED WITH [FORMULA: SEE TEXT] CREATININE-ADJUSTED URINARY ARSENIC [[FORMULA: SEE TEXT]]. SIXTEEN OF THESE CPGS ANNOTATED TO THE [FORMULA: SEE TEXT] ARRAY, AND 10 ASSOCIATIONS WERE REPLICATED ([FORMULA: SEE TEXT]). THE TOP TWO CPGS ANNOTATED UPSTREAM OF THE ABR GENE (CG01912040, CG10003262 ). ALL URINARY ARSENIC-ASSOCIATED CPGS WERE ALSO ASSOCIATED WITH ARSENIC CONCENTRATION MEASURED IN DRINKING WATER ([FORMULA: SEE TEXT]). META-ANALYSIS ([FORMULA: SEE TEXT] SAMPLES) IDENTIFIED 221 URINARY ARSENIC-ASSOCIATED CPGS ([FORMULA: SEE TEXT]). THE ARSENIC-ASSOCIATED CPGS FROM THE META-ANALYSIS WERE ENRICHED IN NON-CPG ISLANDS AND SHORES ([FORMULA: SEE TEXT]) AND DEPLETED IN PROMOTER REGIONS ([FORMULA: SEE TEXT]). AMONG THE ARSENIC-ASSOCIATED CPGS ([FORMULA: SEE TEXT]), WE OBSERVED SIGNIFICANT ENRICHMENT OF GENES ANNOTATING TO THE REACTIVE OXYGEN SPECIES PATHWAY, INFLAMMATORY RESPONSE, AND TUMOR NECROSIS FACTOR [FORMULA: SEE TEXT] ([FORMULA: SEE TEXT]) SIGNALING VIA NUCLEAR FACTOR KAPPA-B ([FORMULA: SEE TEXT]) HALLMARKS ([FORMULA: SEE TEXT]). CONCLUSIONS: THE NOVEL AND REPLICABLE ASSOCIATIONS BETWEEN ARSENIC EXPOSURE AND DNA METHYLATION AT SPECIFIC CPGS OBSERVED IN THIS WORK SUGGEST THAT EPIGENETIC ALTERATIONS SHOULD BE FURTHER INVESTIGATED AS POTENTIAL MEDIATORS IN ARSENIC TOXICITY AND AS BIOMARKERS OF EXPOSURE AND EFFECT IN EXPOSED POPULATIONS. HTTPS://DOI.ORG/10.1289/EHP3849. 2019 18 3081 42 GENOME-WIDE PROMOTER DNA METHYLATION PROFILING OF HEPATOCELLULAR CARCINOMAS ARISING EITHER SPONTANEOUSLY OR DUE TO CHRONIC EXPOSURE TO GINKGO BILOBA EXTRACT (GBE) IN B6C3F1/N MICE. EPIGENETIC MODIFICATIONS, SUCH AS DNA METHYLATION, PLAY AN IMPORTANT ROLE IN CARCINOGENESIS. IN A RECENT NTP STUDY, CHRONIC EXPOSURE OF B6C3F1/N MICE TO GINKGO BILOBA EXTRACT (GBE) RESULTED IN A HIGH INCIDENCE OF HEPATOCELLULAR CARCINOMAS (HCC). GENOME-WIDE PROMOTER METHYLATION PROFILING ON GBE-EXPOSED HCC (2000 MG/KG GROUP), SPONTANEOUS HCC (VEHICLE-CONTROL GROUP), AND AGE-MATCHED VEHICLE CONTROL LIVER WAS PERFORMED TO IDENTIFY DIFFERENTIALLY METHYLATED GENES IN GBE-EXPOSED HCC AND SPONTANEOUS HCC. DNA METHYLATION ALTERATIONS WERE CORRELATED TO THE CORRESPONDING GLOBAL GENE EXPRESSION CHANGES. COMPARED TO CONTROL LIVER, 1296 GENE PROMOTERS (719 HYPERMETHYLATED, 577 HYPOMETHYLATED) IN GBE-EXPOSED HCC AND 738 (427 HYPERMETHYLATED, 311 HYPOMETHYLATED) GENE PROMOTERS IN SPONTANEOUS HCC WERE SIGNIFICANTLY DIFFERENTIALLY METHYLATED, SUGGESTING AN IMPACT OF METHYLATION ON GBE-EXPOSED HCC. DIFFERENTIAL METHYLATION OF PROMOTER REGIONS IN RELEVANT CANCER GENES (CMYC, SPRY2, DUSP5) AND THEIR CORRESPONDING DIFFERENTIAL GENE EXPRESSION WAS VALIDATED BY QUANTITATIVE PYROSEQUENCING AND QRT-PCR, RESPECTIVELY. IN CONCLUSION, WE HAVE IDENTIFIED DIFFERENTIALLY METHYLATED PROMOTER REGIONS OF RELEVANT CANCER GENES ALTERED IN GBE-EXPOSED HCC COMPARED TO SPONTANEOUS HCC. FURTHER STUDY OF UNIQUE SETS OF DIFFERENTIALLY METHYLATED GENES IN CHEMICAL-EXPOSED MOUSE HCC COULD POTENTIALLY BE USED TO DIFFERENTIATE TREATMENT-RELATED TUMORS FROM SPONTANEOUS-TUMORS IN CANCER BIOASSAYS AND PROVIDE ADDITIONAL UNDERSTANDING OF THE UNDERLYING EPIGENETIC MECHANISMS OF CHEMICAL CARCINOGENESIS. 2019 19 5277 33 PROMOTER METHYLATION PROFILE IN PRENEOPLASTIC AND NEOPLASTIC GALLBLADDER LESIONS. GALLBLADDER CARCINOMA (GBC) IS A HIGHLY MALIGNANT NEOPLASM AND REPRESENTS THE LEADING CAUSE OF CANCER DEATH IN CHILEAN WOMEN. IN ORDER TO DETERMINE THE POTENTIAL ROLE OF PROMOTER METHYLATION IN GALLBLADDER CARCINOGENESIS, WE INVESTIGATED THE FREQUENCY OF THIS EPIGENETIC MECHANISM BY METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION (MSP) IN 35 CHRONIC CHOLECYSTITIS (CC, SEPARATED ACCORDING TO THE PRESENCE OR ABSENCE OF METAPLASIA), 19 EARLY CANCERS (MUCOSA OR MUSCULARIS PROPIA INVASION) AND 48 ADVANCED CARCINOMAS WITH INVASION OF THE GALLBLADDER SUBSEROSA (25 CASES) AND SEROSA (23 CASES). WE EXAMINED 14 GENES AND OBSERVED AN INCREASE OF MULTIGENIC METHYLATION DURING TUMORAL PROGRESSION WHICH WAS NOT SIGNIFICANTLY ASSOCIATED WITH THE PATIENT'S AGE. FOUR GENES (DAPK1, DLC1, TIMP3, AND RARBETA2) DISPLAYED A PROGRESSIVE INCREASE IN THEIR METHYLATION STATUS FROM CC WITHOUT METAPLASIA TO ADVANCED CARCINOMA INVADING THE SEROSA LAYER (P