1 6415 122 THE STUDY OF P16 AND P15 GENE METHYLATION IN HEAD AND NECK SQUAMOUS CELL CARCINOMA AND THEIR QUANTITATIVE EVALUATION IN PLASMA BY REAL-TIME PCR. EPIGENETIC SILENCING OF THE P16 AND P15 GENES BY PROMOTER METHYLATION ARE COMMONLY OBSERVED IN HUMAN EPITHELIAL MALIGNANCIES, INCLUDING HEAD AND NECK SQUAMOUS CELL CARCINOMAS (HNSCC). IN THIS STUDY, A METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION (MSP) WAS USED TO EVALUATE THE METHYLATION STATUS OF THE P16 AND P15 GENES IN 73 HNSCC SURGICAL SPECIMENS. P16 AND P15 GENE METHYLATION WAS ALSO EXAMINED IN 29 PAIRED METASTATIC LYMPH NODES AND 29 PAIRED HISTOLOGICALLY, NORMAL RESECTION MARGIN MUCOSAE. THE QUANTITY OF CELL-FREE METHYLATED P16 AND P15 DNA IN THE PLASMA SAMPLES OF 20 HNSCC PATIENTS AND 24 HEALTHY CONTROLS WAS ALSO EXAMINED USING A FLUORESCENCE-BASED REAL-TIME PCR ASSAY. THE FREQUENCIES OF P16 AND P15 METHYLATION IN THE PRIMARY TUMOUR WERE 49% AND 60%, RESPECTIVELY. CONCORDANT METHYLATION OF P16 AND P15 IN TUMOUR SAMPLES AND METASTATIC LYMPH NODES WAS FOUND IN 59 AND 38% OF CASES, RESPECTIVELY. A SIGNIFICANTLY HIGHER PREVALENCE OF P15 METHYLATION WAS FOUND IN HISTOLOGICALLY-NORMAL SURGICAL MARGIN EPITHELIA OF HNSCC PATIENTS WITH CHRONIC SMOKING AND DRINKING HABITS COMPARED WITH NON-SMOKERS AND NON-DRINKERS. IN ADDITION, METHYLATED P16 AND P15 DNA LEVELS WERE SIGNIFICANTLY HIGHER IN THE PLASMA OF HNSCC PATIENTS (MEAN 56 COPIES/ML PLASMA AND 65 COPIES/ML PLASMA, RESPECTIVELY) COMPARED WITH NORMAL CONTROLS (MEAN 6 COPIES/ML PLASMA AND 16 COPIES/ML PLASMA, RESPECTIVELY). IN CONCLUSION, PROMOTER METHYLATION OF THE P16 AND P15 GENES IS INVOLVED IN THE PATHOGENESIS OF HNSCC AND MAY BE RELATED TO CHRONIC SMOKING AND DRINKING. THE DIFFERENTIAL LEVELS OF METHYLATED P16 AND P15 DNA IN PLASMA MIGHT BE POTENTIAL USEFUL MARKERS IN SCREENING HIGH-RISK POPULATIONS FOR EARLY HNSCC AND MONITORING THEIR TREATMENT RESPONSE. 2003 2 5289 43 PROSTANOID RECEPTOR GENES CONFER POOR PROGNOSIS IN HEAD AND NECK SQUAMOUS CELL CARCINOMA VIA EPIGENETIC INACTIVATION. BACKGROUND: CHRONIC INFLAMMATION IS A RISK FACTOR FOR HEAD AND NECK SQUAMOUS CELL CARCINOMA (HNSCC) AND OTHER DISEASES. PROSTANOID RECEPTORS ARE CLEARLY INVOLVED IN THE DEVELOPMENT OF MANY TYPES OF CANCER. HOWEVER, THEIR ROLE IS NOT SIMPLE AND IS POORLY UNDERSTOOD IN HNSCC. METHODS: METHYLATION PROFILES OF PROSTANOID RECEPTOR FAMILY GENES WERE GENERATED FOR TUMOUR SAMPLES OBTAINED FROM 274 PATIENTS WITH HNSCC, INCLUDING 69 HYPOPHARYNX, 51 LARYNX, 79 ORAL CAVITY, AND 75 OROPHARYNX TUMOUR SAMPLES, BY QUANTITATIVE METHYLATION-SPECIFIC PCR. PROMOTER METHYLATION WAS THEN EVALUATED WITH RESPECT TO VARIOUS CLINICAL CHARACTERISTICS AND PATIENT SURVIVAL. RESULTS: THE MEAN NUMBER OF METHYLATED GENES PER SAMPLE WAS 2.05 +/- 2.59 (RANGE 0 TO 9). PROMOTERS OF PTGDR1, PTGDR2, PTGER1, PTGER2, PTGER3, PTGER4, PTGFR, PTGIR, AND TBXA2R WERE METHYLATED IN 43.8%, 18.2%, 25.5%, 17.5%, 41.2%, 8.0%, 19.3%, 20.4%, AND 11.3% OF THE SAMPLES, RESPECTIVELY. METHYLATION INDICES FOR PROSTANOID RECEPTOR FAMILY GENES TENDED TO BE HIGHER AS THE NUMBER OF TET METHYLATION EVENTS INCREASED. PATIENTS WITH 5-9 METHYLATED GENES HAD A SIGNIFICANTLY LOWER SURVIVAL RATE THAN THAT OF PATIENTS WITH 0-4 METHYLATED GENES (LOG-RANK TEST, P= 0.007). IN MULTIVARIATE ANALYSES, PTGDR1 METHYLATION WAS MOST HIGHLY CORRELATED WITH RECURRENCE IN PATIENTS WITH HYPOPHARYNGEAL CANCER (P = 0.014). A SIMILAR CORRELATION WAS OBSERVED FOR PTGER4 IN PATIENTS WITH LARYNGEAL CANCER (P = 0.046). METHYLATION OF THE PTGIR AND TBXA2R PROMOTERS WAS POSITIVELY CORRELATED WITH RECURRENCE IN OROPHARYNGEAL CANCER (P = 0.028 AND P = 0.006, RESPECTIVELY). MOREOVER, PATIENTS WITH 5-9 METHYLATED GENES WERE EXTREMELY LOWER OF 5HMC LEVELS (P = 0.035) AND WAS CORRELATED WITH INCREASING EXPRESSION OF DNMT3A AND DNMT3B (P < 0.05 AND P < 0.05, RESPECTIVELY). CONCLUSION: WE CHARACTERISED THE RELATIONSHIP BETWEEN THE METHYLATION STATUS OF PROSTANOID RECEPTOR GENES AND RECURRENCE IN HNSCC. THESE RESULTS PROVIDE NEW PERSPECTIVES FOR THE DEVELOPMENT OF MOLECULAR TARGETED TREATMENT APPROACHES. 2020 3 740 32 CANCER/TESTIS ANTIGENS: EXPRESSION, REGULATION, TUMOR INVASION, AND USE IN IMMUNOTHERAPY OF CANCERS. CANCER/TESTIS ANTIGENS (CTAS) ARE NAMED BASED ON THEIR EXPRESSION PATTERN THAT IS RESTRICTED IN A NUMBER OF NORMAL AND ABNORMAL TISSUES. TUMOR CELLS FREQUENTLY EXPRESS ANTIGENS WHOSE EXPRESSION IS TYPICALLY RESTRICTED TO GERM CELLS. THEIR UNIQUE EXPRESSION PATTERN IS GUARANTEED BY PRECISE EPIGENETIC REGULATORY MECHANISMS. BECAUSE OF THEIR TUMOR-LIMITED, HIGH IMMUNOGENICITY, AND BIASED EXPRESSION, DISCOVERY OF THESE MOLECULES PROVIDES UNPRECEDENTED OPPORTUNITIES FOR FURTHER RESEARCH AND CLINICAL DEVELOPMENT IN THE FIELD OF CANCER DIAGNOSIS AND IMMUNOTHERAPY. EVOLVING EVIDENCE REVEALS THAT A NUMBER OF CTAS STIMULATE EPITHELIAL MESENCHYMAL TRANSITION (EMT) AND GENERATION OF CANCER STEM-LIKE CELLS, INTENSIFYING METASTASIS, INVASION, AND TUMORIGENESIS. BASED ON THESE FEATURES, CTAS ATTRACT ATTENTION TO BE CONSIDERED AS IDEAL TARGETS FOR DEVELOPING SEVERAL CLINICAL TRIALS, MANY OF THEM CONCENTRATING ON CTA VACCINE THERAPY. ACCORDING TO RECENT PRACTICAL CLINICAL INTEREST, MORE CHARACTERIZATIONS OF CTA REGULATION ARE IDENTIFIED. CTA EXPRESSION HAS BEEN DEMONSTRATED IN A VARIETY OF HUMAN CANCER TISSUES, AND SOME OF THEM HAVE BEEN FOUND TO ELICIT HUMORAL AND/OR CELLULAR IMMUNE RESPONSES IN CANCER PATIENTS. CTAS ARE BRILLIANT TARGETS FOR ANTICANCER DRUG DISCOVERY, TARGETED TUMOR THERAPY, AND DIAGNOSTIC BIOMARKERS, FURTHERMORE, VALUED GENES IN THE STUDY OF IMMUNOTHERAPY, PROMOTING TUMORIGENESIS, AND MALIGNANT PROGRESSION. THIS REVIEW OUTLINES AND CATEGORIZES OUR CURRENT UNDERSTANDING OF THE COMPLEX AND BIASED PROCESS OF CTAS MRNA AND PROTEIN EXPRESSION IN CANCER, AND SUPPLIES THE MOST RECENT INFORMATION ON THEIR REGULATION AND FUNCTION. BESIDES, A CONCISE SYNOPSIS OF THE MAJOR CLINICAL TRIALS INVOLVING CTAS, AS THERAPEUTIC AVENUES, IS DISCUSSED. ABBREVIATIONS: AIRE: AUTOIMMUNE REGULATOR; CAMP: CYCLIC ADENOSINE 3',5'-CYCLIC MONOPHOSPHATE; CEA: CARCINOEMBRYONIC ANTIGEN; CML: CHRONIC MYELOID LEUKEMIA; CREB: CYCLICAMP RESPONSE ELEMENT BINDING; CSCS: CANCER STEM CELLS; CTAS: CANCER/TESTIS ANTIGENS; CTL: CYTOTOXIC T LYMPHOCYTE; DCS: DENDRITIC CELLS; EMT: EPITHELIAL-MESENCHYMAL TRANSITION; ERK: EXTRACELLULAR SIGNAL-REGULATED KINASE; ESCC: ESOPHAGEAL SQUAMOUS CELL CARCINOMA; ETS: E26 TRANSFORMATION-SPECIFIC; HIS: HISTIDINE; HLA: HUMAN LEUKOCYTE ANTIGEN; HNSCC: HEAD AND NECK SQUAMOUS CELL CARCINOMA; IFN-GAMMA: INTERFERON-GAMMA; IHC: IMMUNOHISTOCHEMISTRY; IL-7: INTERLEUKIN7; MHC: MAJOR HISTOCOMPATIBILITY COMPLEX; MMP2: MATRIX METALLOPROTEINASE 2; MTECS: MEDULLARY THYMUS EPITHELIAL CELLS; MUC1: MUCIN 1; NSCLC: NON-SMALL CELL LUNG CANCER; PRAME: PREFERENTIALLY EXPRESSED ANTIGEN IN MELANOMA; RDA: REPRESENTATIONAL DIFFERENCE ANALYSIS; SEREX: SEROLOGICAL ANALYSIS OF CDNA EXPRESSION; SSX: SYNOVIAL SARCOMA X CHROMOSOME; TAAS: TUMOR-ASSOCIATED ANTIGENS; TCR: T-CELL RECEPTOR; TCGA: THE CANCER GENOME ATLAS; TGF-BETA: TRANSFORMING GROWTH FACTOR-BETA. 2016 4 1624 34 DNA-METHYLOME-BASED TUMOR HYPOXIA CLASSIFIER IDENTIFIES HPV-NEGATIVE HEAD AND NECK CANCER PATIENTS AT RISK FOR LOCOREGIONAL RECURRENCE AFTER PRIMARY RADIOCHEMOTHERAPY. PURPOSE: TUMOR HYPOXIA IS A PARADIGMATIC NEGATIVE PROGNOSTICATOR OF TREATMENT RESISTANCE IN HEAD AND NECK SQUAMOUS CELL CARCINOMA (HNSCC). THE LACK OF ROBUST AND RELIABLE HYPOXIA CLASSIFIERS LIMITS THE ADAPTATION OF STRATIFIED THERAPIES. WE HYPOTHESIZED THAT THE TUMOR DNA METHYLATION LANDSCAPE MIGHT INDICATE EPIGENETIC REPROGRAMMING INDUCED BY CHRONIC INTRATUMORAL HYPOXIA. EXPERIMENTAL DESIGN: A DNA-METHYLOME-BASED TUMOR HYPOXIA CLASSIFIER (HYPOXIA-M) WAS TRAINED IN THE TCGA (THE CANCER GENOME ATLAS)-HNSCC COHORT BASED ON MATCHED ASSIGNMENTS USING GENE EXPRESSION-BASED SIGNATURES OF HYPOXIA (HYPOXIA-GES). HYPOXIA-M WAS VALIDATED IN A MULTICENTER DKTK-ROG TRIAL CONSISTING OF HUMAN PAPILLOMAVIRUS (HPV)-NEGATIVE PATIENTS WITH HNSCC TREATED WITH PRIMARY RADIOCHEMOTHERAPY (RCHT). RESULTS: ALTHOUGH HYPOXIA-GES FAILED TO STRATIFY PATIENTS IN THE DKTK-ROG, HYPOXIA-M WAS INDEPENDENTLY PROGNOSTIC FOR LOCAL RECURRENCE (HR, 4.3; P = 0.001) AND OVERALL SURVIVAL (HR, 2.34; P = 0.03) BUT NOT DISTANT METASTASIS AFTER RCHT IN BOTH COHORTS. HYPOXIA-M STATUS WAS INVERSELY ASSOCIATED WITH CD8 T-CELL INFILTRATION IN BOTH COHORTS. HYPOXIA-M WAS FURTHER PROGNOSTIC IN THE TCGA-PANCANCER COHORT (HR, 1.83; P = 0.04), UNDERSCORING THE BREADTH OF THIS CLASSIFIER FOR PREDICTING TUMOR HYPOXIA STATUS. CONCLUSIONS: OUR FINDINGS HIGHLIGHT AN UNEXPLORED AVENUE FOR DNA METHYLATION-BASED CLASSIFIERS AS BIOMARKERS OF TUMORAL HYPOXIA FOR IDENTIFYING HIGH-RISK FEATURES IN PATIENTS WITH HNSCC TUMORS. SEE RELATED COMMENTARY BY HEFT NEAL AND BRENNER, P. 2954. 2023 5 5382 31 RECURRENT CHROMOSOMAL AND EPIGENETIC ALTERATIONS IN ORAL SQUAMOUS CELL CARCINOMA AND ITS PUTATIVE PREMALIGNANT CONDITION ORAL LICHEN PLANUS. HEAD AND NECK SQUAMOUS CELL CARCINOMA (HNSCC) AFFECTS ABOUT 700.000 INDIVIDUALS PER YEAR WORLDWIDE WITH ORAL SQUAMOUS CELL CARCINOMA (OSCC) AS A MAJOR SUBCATEGORY. DESPITE A COMPREHENSIVE TREATMENT CONCEPT INCLUDING SURGERY, RADIATION, AND CHEMOTHERAPY THE 5-YEAR SURVIVAL RATE IS STILL ONLY ABOUT 50 PERCENT. CHRONIC INFLAMMATION IS ONE OF THE HALLMARKS OF CARCINOGENESIS. UNTIL NOW, LITTLE IS KNOWN ABOUT THE PREMALIGNANT STATUS OF ORAL LICHEN PLANUS (OLP) AND MOLECULAR ALTERATIONS IN OLP ARE STILL POORLY CHARACTERIZED. OUR STUDY AIMS TO DELINEATE DIFFERENTIAL DNA METHYLATION PATTERNS IN OLP, OSCC, AND NORMAL ORAL MUCOSA. BY APPLYING A BEAD CHIP APPROACH, WE IDENTIFIED ALTERED CHROMOSOMAL PATTERNS CHARACTERISTIC FOR OSCC WHILE FINDING NO RECURRENT ALTERATIONS IN OLP. IN CONTRAST, WE IDENTIFIED NUMEROUS ALTERATIONS IN THE DNA METHYLATION PATTERN IN OLP, AS COMPARED TO NORMAL CONTROLS, THAT WERE ALSO PRESENT IN OSCC. OUR DATA SUPPORT THE HYPOTHESIS THAT OLP IS A PRECURSOR LESION OF OSCC SHARING MULTIPLE EPIGENETIC ALTERATIONS WITH OSCC. 2019 6 2678 24 EVALUATION OF A PROGNOSTIC EPIGENETIC CLASSIFICATION SYSTEM IN CHRONIC LYMPHOCYTIC LEUKEMIA PATIENTS. BACKGROUND: METHYLATION AT 5 CPG SITES WAS PREVIOUSLY SHOWN TO CLASSIFY CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) INTO 3 PROGNOSTIC SUBGROUPS. HERE, WE AIMED TO VALIDATE THE MARKER SET IN AN ADDITIONAL COHORT AND TO EVALUATE ITS CLINICAL UTILITY FOR CLL PATIENT STRATIFICATION. METHODS: WE EVALUATED THIS EPIGENETIC MARKER SET IN 79 GERMAN PATIENTS USING BISULFITE TREATMENT FOLLOWED BY PYROSEQUENCING AND CLASSIFICATION USING A SUPPORT VECTOR MACHINE-LEARNING TOOL. RESULTS: THE N-CLL, I-CLL, AND M-CLL CLASSIFICATION WAS DETECTED IN 28 (35%), 10 (13%), AND 41 (51%) PATIENTS, RESPECTIVELY. EPIGENETIC GROUPING WAS ASSOCIATED WITH IGHV MUTATIONAL STATUS (P = 2 X 10(-12)), ISOLATED DEL13Q (P = 9 X 10(-6)), DEL17P (P = .015), COMPLEX KARYOTYPE (P = .005), VH-USAGE, AND CLINICAL OUTCOME AS TIME TO FIRST TREATMENT (P = 1.4 X 10(-12)) AND OVERALL SURVIVAL (P = .003). MULTIVARIATE COX REGRESSION ANALYSIS IDENTIFIED N-CLL AS A FACTOR FOR EARLIER TREATMENT HAZARD RATIO (HR), 6.3 (95% CONFIDENCE INTERVAL [CI] 2.4-16.4; P = .0002) COMPARED TO IGHV MUTATIONAL STATUS (HR 4.6, 95% CI 1.9-11.3, P = .0008). IN ADDITION, WHEN COMPARING THE PROGNOSTIC VALUE OF THE EPIGENETIC CLASSIFICATION SYSTEM WITH THE IGHV CLASSIFICATION, EPIGENETIC GROUPING PERFORMED BETTER COMPARED TO IGHV MUTATIONAL STATUS USING KAPLAN-MEIER ESTIMATION AND ALLOWED THE IDENTIFICATION OF A THIRD, INTERMEDIATE (I-CLL) GROUP. THUS, OUR STUDY CONFIRMED THE PROGNOSTIC VALUE OF THE EPIGENETIC MARKER SET FOR PATIENT STRATIFICATION IN ROUTINE CLINICAL DIAGNOSTICS. 2022 7 2355 23 EPIGENETIC REGULATION OF PRAME GENE IN CHRONIC MYELOID LEUKEMIA. TUMOR ASSOCIATED ANTIGENS (TAA) PROVIDE ATTRACTIVE TARGETS FOR CANCER-SPECIFIC IMMUNOTHERAPY. PRAME IS A TAA GENE UP-REGULATED IN ADVANCED PHASES OF CHRONIC MYELOID LEUKEMIA (CML). TO DATE, MOLECULAR MECHANISMS FOR THE EXPRESSION OF PRAME HAVE NEVER BEEN STUDIED. WE FOUND THAT SOME PH'-POSITIVE CELL LINES DID NOT EXPRESS PRAME. THE EXPRESSION OF PRAME WAS RESTORED IN THESE CELL LINES BY TREATMENT WITH 5'-AZA-2'-DEOXYCYTIDINE, SUGGESTING THAT THE EXPRESSION OF PRAME IS MAINLY SUPPRESSED BY HYPERMETHYLATION. BISULFITE SEQUENCING ANALYSIS OF THE CPG SITES OF THE PRAME EXON 2 IN THESE CANCER CELL LINES REVEALED A CLOSE RELATIONSHIP BETWEEN THE METHYLATION STATUS OF THE PRAME GENE AND ITS EXPRESSION. A METHYLATION-SPECIFIC PCR ANALYSIS DEMONSTRATED THAT HYPOMETHYLATION OF PRAME WAS SIGNIFICANTLY MORE FREQUENT IN CML BLAST CRISIS (70%) THAN IN CHRONIC PHASE (36%) (P=0.01) AND WAS CORRELATED WITH HIGH EXPRESSION LEVELS OF PRAME TRANSCRIPTS (P<0.0001). THESE RESULTS SUGGEST THAT HYPOMETHYLATION OF PRAME UP-REGULATES ITS EXPRESSION IN CML AND MIGHT PLAY A SIGNIFICANT ROLE IN THE PROGRESSION OF THE DISEASE. 2007 8 2439 40 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 9 1495 30 DNA HYPERMETHYLATION OF CELL CYCLE (P15 AND P16) AND APOPTOTIC (P14, P53, DAPK AND TMS1) GENES IN PERIPHERAL BLOOD OF LEUKEMIA PATIENTS. ABERRANT DNA METHYLATION OF TUMOR SUPPRESSOR GENES HAS BEEN REPORTED IN ALL MAJOR TYPES OF LEUKEMIA WITH POTENTIAL INVOLVEMENT IN THE INACTIVATION OF REGULATORY CELL CYCLE AND APOPTOSIS GENES. HOWEVER, MOST OF THE PREVIOUS REPORTS DID NOT SHOW THE EXTENT OF CONCURRENT METHYLATION OF MULTIPLE GENES IN THE FOUR LEUKEMIA TYPES. HERE, WE ANALYZED SIX KEY GENES (P14, P15, P16, P53, DAPK AND TMS1) FOR DNA METHYLATION USING METHYLATION SPECIFIC PCR TO ANALYZE PERIPHERAL BLOOD OF 78 LEUKEMIA PATIENTS (24 CML, 25 CLL, 12 AML, AND 17 ALL) AND 24 HEALTHY VOLUNTEERS. IN CML, METHYLATION WAS DETECTED FOR P15 (11%), P16 (9%), P53 (23%) AND DAPK (23%), IN CLL, P14 (25%), P15 (19%), P16 (12%), P53 (17%) AND DAPK (36%), IN AML, P14 (8%), P15 (45%), P53 (9%) AND DAPK (17%) AND IN ALL, P15 (14%), P16 (8%), AND P53 (8%). THIS STUDY HIGHLIGHTED AN ESSENTIAL ROLE OF DAPK METHYLATION IN CHRONIC LEUKEMIA IN CONTRAST TO P15 METHYLATION IN THE ACUTE CASES, WHEREAS TMS1 HYPERMETHYLATION WAS ABSENT IN ALL CASES. FURTHERMORE, HYPERMETHYLATION OF MULTIPLE GENES PER PATIENT WAS OBSERVED, WITH OBVIOUS SELECTIVENESS IN THE 9P21 CHROMOSOMAL REGION GENES (P14, P15 AND P16). INTERESTINGLY, METHYLATION OF P15 INCREASED THE RISK OF METHYLATION IN P53, AND VICE VERSA, BY FIVE FOLDS (P=0.03) INDICATING POSSIBLE SYNERGISTIC EPIGENETIC DISRUPTION OF DIFFERENT PHASES OF THE CELL CYCLE OR BETWEEN THE CELL CYCLE AND APOPTOSIS. THE INVESTIGATION OF MULTIPLE RELATIONSHIPS BETWEEN METHYLATED GENES MIGHT SHED LIGHT ON TUMOR SPECIFIC INACTIVATION OF THE CELL CYCLE AND APOPTOTIC PATHWAYS. 2014 10 3294 32 HIGH INCIDENCE OF MGMT AND RARBETA PROMOTER METHYLATION IN PRIMARY GLIOBLASTOMAS: ASSOCIATION WITH HISTOPATHOLOGICAL CHARACTERISTICS, INFLAMMATORY MEDIATORS AND CLINICAL OUTCOME. GLIOBLASTOMAS, THE MOST FREQUENT PRIMARY BRAIN TUMORS IN ADULTS, ARE CHARACTERIZED BY A HIGHLY AGGRESSIVE, INFLAMMATORY AND ANGIOGENIC PHENOTYPE. METHYLATION OF CPG ISLANDS IN CANCER-RELATED GENES MAY SERVE AS AN EPIGENETIC BIOMARKER FOR GLIOBLASTOMA DIAGNOSIS AND PROGNOSIS. THE AIM OF THIS STUDY WAS TO ANALYZE THE METHYLATION STATUS OF FOUR CRITICAL TUMOR-ASSOCIATED GENES (MGMT, RARBETA, RASSF1A, CDH13), AND INVESTIGATE POSSIBLE LINKS WITH INFLAMMATORY (INTERLEUKIN [IL]-6, IL-8) AND ANGIOGENIC MEDIATORS (VASCULAR ENDOTHELIAL GROWTH FACTOR [VEGF], CYCLOOXYGENASE [COX]-2) AND CLINICAL OUTCOME IN 23 GLIOMA SAMPLES (6 GRADE II ASTROCYTOMAS, 17 GRADE IV GLIOBLASTOMAS). RARBETA AND MGMT GENES WERE MORE FREQUENTLY METHYLATED IN 70.58% AND 58.8% OF GLIOBLASTOMAS, RESPECTIVELY. RASSF1A AND CDH13 DISPLAYED A SIMILAR METHYLATION FREQUENCY (23.52%) IN GLIOBLASTOMAS. NO GENE METHYLATION WAS OBSERVED IN GRADE II ASTROCYTOMAS. TUMOR GRADE CORRELATED POSITIVELY WITH MGMT AND RARBETA METHYLATION (P = 0.005 AND P = 0.019, RESPECTIVELY) AND THE EXTENT OF NECROSIS (P = 0.001 AND P = 0.003). INTERESTINGLY, THE MARKER OF CHRONIC INFLAMMATION, IL-6, WAS POSITIVELY ASSOCIATED WITH METHYLATION OF MGMT (P = 0.004), RARBETA (P = 0.002), AND RASSF1A (P = 0.0081) AS WELL AS THE TOTAL NUMBER OF METHYLATED GENES (P < 0.0001), INDICATING THE IMPORTANT ROLE OF IL-6 IN MAINTAINING PROMOTER METHYLATION OF THESE GENES. VEGF EXPRESSION CORRELATED POSITIVELY WITH MGMT AND RARBETA METHYLATION ALTHOUGH THESE RELATIONSHIPS WERE OF MARGINAL SIGNIFICANCE (P = 0.0679 AND P = 0.0757). KAPLAN-MEIER UNIVARIATE SURVIVAL ANALYSIS INDICATED AN UNFAVORABLE SURVIVAL PERIOD IN PATIENTS WITH MGMT METHYLATION COMPARED WITH THOSE WITHOUT METHYLATION (P = 0.0474). OUR STUDY HIGHLIGHTS THE IMPLICATION OF MGMT AND RARBETA METHYLATION IN THE AGGRESSIVE PHENOTYPE OF PRIMARY GLIOBLASTOMAS. THE ASSOCIATION OF MGMT METHYLATION WITH CLINICAL OUTCOME INDICATES ITS POTENTIAL PROGNOSTIC VALUE. 2010 11 4903 30 P16 PROMOTER HYPERMETHYLATION IN HUMAN HEPATOCELLULAR CARCINOMA WITH OR WITHOUT HEPATITIS VIRUS INFECTION. BACKGROUND: EPIGENETIC ALTERATION THROUGH METHYLATION IS ONE OF THE MOST IMPORTANT STEPS IN CARCINOGENESIS. HOWEVER, THE RELATION BETWEEN HEPATITIS VIRUS INFECTION AND EPIGENETIC ALTERATIONS IS POORLY UNDERSTOOD. METHODS: SIXTEEN PATIENTS WITHOUT HEPATITIS B VIRUS (HBV) AND HEPATITIS C VIRUS (HCV) AND 35 PATIENTS WITH HBV OR HCV WHO UNDERWENT LIVER RESECTION FOR HEPATOCELLULAR CARCINOMA (HCC) WERE STUDIED. MUTATION OF P53 WAS DETECTED BY DIRECT SEQUENCING. METHYLATION STATUS OF P16 WAS EVALUATED IN TUMOR AND NONCANCEROUS LIVER TISSUES BY METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION. RESULTS: IN HCC WITHOUT HBV AND HCV, P53 MUTATIONS WERE DETECTED IN 5 (31%) OF 16 HCCS. METHYLATION OF P16 PROMOTER WAS DETECTED IN 2 (25%) OF 8 MODERATELY DIFFERENTIATED HCCS, 6 (75%) OF 8 POORLY DIFFERENTIATED HCCS, AND NONE OF 16 NONCANCEROUS TISSUE SPECIMENS. IN HCC WITH HBV OR HCV, P53 MUTATIONS WERE DETECTED IN 8 (23%) OF 35 HCCS. METHYLATION OF P16 PROMOTER WAS DETECTED IN 2 (100%) OF 2 WELL-DIFFERENTIATED HCCS, 13 (76%) OF 17 MODERATELY DIFFERENTIATED HCCS, 12 (75%) OF 16 POORLY DIFFERENTIATED HCCS, AND 9 (26%) OF 35 NONCANCEROUS LIVER TISSUE SPECIMENS. CONCLUSIONS: OUR RESULTS SUGGEST THAT HEPATITIS VIRUSES MIGHT INDUCE METHYLATION OF P16 PROMOTER IN LIVER WITH CHRONIC INFLAMMATION, BEFORE APPEARANCE OF HCC. 2004 12 150 36 ABERRANT HYPOMETHYLATION OF THE CANCER-TESTIS ANTIGEN PRAME CORRELATES WITH PRAME EXPRESSION IN ACUTE MYELOID LEUKEMIA. PRAME IS A TUMOR-ASSOCIATED ANTIGEN, WHICH BELONGS TO THE FAMILY OF CANCER-TESTIS ANTIGENS (CTA). THE EXPRESSION OF CTA IS MAINLY RESTRICTED TO THE TESTIS AND VARIOUS TUMORS. IN CONTRAST TO OTHER CTA, PRAME EXPRESSION IS ALSO FREQUENTLY DETECTED IN ACUTE AND CHRONIC LEUKEMIAS. DUE TO THIS EXPRESSION PATTERN, PRAME HAS ATTRACTED GREAT INTEREST AS A PROGNOSTIC TUMOR MARKER THAT CAN BE USED FOR THE DETECTION OF MINIMAL RESIDUAL DISEASE AND AS A POTENTIAL TARGET FOR IMMUNOTHERAPY. IN ACUTE MYELOID LEUKEMIA (AML), PRAME EXPRESSION HAS BEEN OBSERVED IN 30-64% OF CASES. TO EVALUATE WHETHER EPIGENETIC MECHANISMS CONTRIBUTE TO PRAME ACTIVATION IN AML, WE STUDIED DNA METHYLATION OF 15 CPG DINUCLEOTIDES WITHIN A CPG-RICH REGION LOCATED IN THE INTRON 1 OF THE PRAME GENE. DNA METHYLATION WAS DETERMINED BY SEQUENCE ANALYSIS OF CLONED PCR PRODUCTS GENERATED FROM BISULFITE-TREATED GENOMIC DNA. METHYLATION PATTERNS WERE CORRELATED WITH PRAME MRNA LEVELS AS DETERMINED BY MICROARRAY ANALYSIS AND REAL-TIME PCR. WE FOUND ALMOST COMPLETE METHYLATION IN MONONUCLEAR BLOOD CELLS FROM TWO HEALTHY DONORS AND IN BONE MARROW CELLS OF FOUR PRAME-NEGATIVE AML PATIENTS. IN CONTRAST, THE DEGREE OF PRAME METHYLATION WAS CLEARLY REDUCED IN FOUR PRAME-POSITIVE AML BONE MARROW SAMPLES. IN PARTICULAR, THESE SAMPLES WERE CHARACTERIZED BY THE PRESENCE OF CLONES, WHICH WERE COMPLETELY DEVOID OF METHYLATION. THE SIGNIFICANT INVERSE CORRELATION BETWEEN THE DEGREE OF METHYLATION AND PRAME EXPRESSION SUGGESTS A CAUSAL ROLE OF DNA METHYLATION IN PRAME REGULATION. SUCH A ROLE IS FURTHER SUPPORTED BY THE OBSERVATION THAT TREATMENT OF PRAME-NEGATIVE CELL LINES U-937 AND THP-1 WITH THE DEMETHYLATING AGENT 5'-AZA-2'DC RESULTED IN A DOSE-RELATED UPREGULATION OF PRAME EXPRESSION. 2008 13 672 31 BRAF, KRAS AND HELICOBACTER PYLORI EPIGENETIC CHANGES-ASSOCIATED CHRONIC GASTRITIS IN EGYPTIAN PATIENTS WITH AND WITHOUT GASTRIC CANCER. WE AIMED TO STUDY MLH1 AND MGMT METHYLATION STATUS IN HELICOBACTER PYLORI-ASSOCIATED CHRONIC GASTRITIS IN EGYPTIAN PATIENTS WITH AND WITHOUT GASTRIC CANCER. 39 PATIENTS WERE INCLUDED IN OUR STUDY. THEY WERE DIVIDED INTO 2 GROUPS; PATIENTS WITHOUT (GROUP I) AND WITH GASTRIC ADENOCARCINOMA (GROUP II). PATIENTS WERE SUBJECTED TO CLINICAL EXAMINATION, ABDOMINAL ULTRASOUND AND UPPER ENDOSCOPY FOR GASTRIC BIOPSY. BIOPSIES WERE SUBJECTED TO UREASE TEST, HISTOLOGICAL EXAMINATION, AND DNA PURIFICATION. H. PYLORI, BRAF, KRAS, MLH1 AND MGMT METHYLATION WERE ASSESSED BY QUANTITATIVE PCR. DNA SEQUENCING WAS PERFORMED TO ASSESS BRAF AND KRAS GENES MUTATION. QPCR OF H. PYLORI WAS SIGNIFICANTLY HIGHER IN PATIENTS WITH ADENOCARCINOMA (GROUP II) THAN THOSE WITHOUT ADENOCARCINOMA (GROUP I); WITH A P < 0.001 AS WELL AS IN PATIENTS WITH AGE ABOVE 50 YEARS WITH A P VALUE = 0.008. BY APPLYING LOGISTIC REGRESSION ANALYSIS IT WAS REPORTED THAT THE H. PYLORI QPCR IS A SIGNIFICANT PREDICTOR TO THE ADENOCARCINOMA WITH OR = 1.025 (95 % CI: 1. 002-1.048), WITH SENSITIVITY OF 90 % AND SPECIFICITY OF 100 %. ADENOCARCINOMA PATIENTS HAD A SIGNIFICANTLY HIGHER MEAN AGE AND LEVELS OF H. PYLORI, BRAF, K-RAS, METHYLATED MGMT AND METHYLATED MLH1 THAN THOSE OF GASTRITIS PATIENTS. DNA SEQUENCE ANALYSIS OF BRAF (CODON 12) AND KRAS (CODON 600) HAD GENES MUTATION IN GASTRIC ADENOCARCINOMA VERSUS CHRONIC GASTRITIS. CONCLUSION: H. PYLORI MAY CAUSE EPIGENETIC CHANGES PREDISPOSING THE PATIENTS TO CANCER STOMACH. ESTIMATION OF H. PYLORI BY QPCR CAN BE A GOOD PREDICTOR TO ADENOCARCINOMA. BRAF AND KRAS GENES MUTATION WERE REVELED IN GASTRITIS AND ADENOCARCINOMA PATIENTS. 2016 14 5243 24 PROGNOSTIC IMPACT OF EPIGENETIC CLASSIFICATION IN CHRONIC LYMPHOCYTIC LEUKEMIA: THE CASE OF SUBSET #2. BASED ON THE METHYLATION STATUS OF 5 SINGLE CPG SITES, A NOVEL EPIGENETIC CLASSIFICATION OF CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) WAS RECENTLY PROPOSED, CLASSIFYING CLL PATIENTS INTO 3 CLINICO-BIOLOGICAL SUBGROUPS WITH DIFFERENT OUTCOME, TERMED MEMORY LIKE CLL (M-CLL), NAIVE LIKE CLL (N-CLL), AND A THIRD INTERMEDIATE CLL SUBGROUP (I-CLL). WHILE M-CLL AND N-CLL PATIENTS AT LARGE CORRESPONDED TO PATIENTS CARRYING MUTATED AND UNMUTATED IGHV GENES, RESPECTIVELY, LIMITED INFORMATION EXISTS REGARDING THE LESS DEFINED I-CLL GROUP. USING PYROSEQUENCING, WE INVESTIGATED THE PROGNOSTIC IMPACT OF THE PROPOSED 5 CPG SIGNATURE IN A WELL-CHARACTERIZED CLL COHORT (135 CASES), INCLUDING IGHV-MUTATED AND UNMUTATED PATIENTS AS WELL AS CLINICALLY AGGRESSIVE STEREOTYPED SUBSET #2 PATIENTS. OVERALL, WE CONFIRMED THE SIGNATURE'S ASSOCIATION WITH ESTABLISHED PROGNOSTIC MARKERS. MOREOVER, IN THE PRESENCE OF THE IGHV MUTATIONAL STATUS, THE EPIGENETIC SIGNATURE REMAINED INDEPENDENTLY ASSOCIATED WITH BOTH TIME-TO-FIRST-TREATMENT AND OVERALL SURVIVAL IN MULTIVARIATE ANALYSES. AS A PRIME FINDING, WE OBSERVED THAT SUBSET #2 PATIENTS WERE PREDOMINANTLY CLASSIFIED AS I-CLL, PROBABLY REFLECTING THEIR BORDERLINE IGHV MUTATIONAL STATUS (97-99% GERMLINE IDENTITY), THOUGH HAVING A SIMILARLY POOR PROGNOSIS AS N-CLL PATIENTS. IN SUMMARY, WE VALIDATED THE EPIGENETIC CLASSIFIER AS AN INDEPENDENT FACTOR IN CLL PROGNOSTICATION AND PROVIDE FURTHER EVIDENCE THAT SUBSET #2 IS A MEMBER OF THE I-CLL GROUP, HENCE SUPPORTING THE EXISTENCE OF A THIRD, INTERMEDIATE EPIGENETIC SUBGROUP. 2016 15 2847 30 FREQUENT P15 PROMOTER METHYLATION IN TUMOR AND PERIPHERAL BLOOD FROM HEPATOCELLULAR CARCINOMA PATIENTS. WE PROSPECTIVELY ANALYZED P15 METHYLATION PATTERNS IN 25 SURGICALLY RESECTED TUMORS AND 130 PLASMA, SERUM, AND BUFFY COAT SAMPLES FROM HEPATOCELLULAR CARCINOMA (HCC) PATIENTS, CONTROLS WITH CHRONIC HEPATITIS/CIRRHOSIS, AND HEALTHY SUBJECTS. USING METHYLATION-SPECIFIC PCR, WE DEMONSTRATED FOR THE FIRST TIME P15 PROMOTER METHYLATION IN 64% OF TUMORS AND 25% (4 OF 16) OF PATIENTS' PLASMA AND SERUM SAMPLES. CONCURRENT P15 AND P16 METHYLATION WAS SHOWN IN 48% OF TUMORS, AND P15/P16 METHYLATION WAS DETECTED IN THE PLASMA/SERUM OF 92% (11 OF 12) OF PATIENTS. OF NOTE, 75% OF 12 PATIENTS WITH CONCURRENT TUMOR METHYLATION DEVELOPED CLINICAL METASTASIS/RECURRENCE (P = 0.027). IN BUFFY COAT SAMPLES, P15 METHYLATION WAS DETECTED IN ALL EIGHT PATIENTS WITH TUMOR P15 METHYLATION, SUGGESTING THE PRESENCE OF CIRCULATING TUMOR CELLS. NONE OF THE CONTROL SAMPLES WERE METHYLATION POSITIVE. OUR DATA UNDERSCORE THE IMPORTANT ROLE(S) OF P15 AND P16 METHYLATION IN HEPATOCARCINOGENESIS AND TUMOR PROGRESSION. AMONG 92% (23 OF 25) OF PATIENTS WITH TUMOR P15/P16 METHYLATION, CIRCULATING TUMOR DNA AND HCC CELLS WERE DETECTED IN THE PERIPHERAL BLOOD OF 87% (20 OF 23) OF PATIENTS. THE COMBINATION OF THESE EPIGENETIC MARKERS MAY PROVE VALUABLE FOR NONINVASIVE HCC DIAGNOSIS AND DISEASE MONITORING. 2000 16 6770 49 [ABERRANT METHYLATION OF MULTIPLE GENES AND ITS CLINICAL IMPLICATION IN HEPATOCELLULAR CARCINOMA]. OBJECTIVE: TO INVESTIGATE THE METHYLATION FREQUENCIES OF MULTIPLE TUMOR SUPPRESSOR GENES (TSGS) IN HEPATOCELLULAR CARCINOMA (HCC) AND THE CLINICAL IMPLICATION OF ABERRANT DNA METHYLATION IN MOLECULAR CARCINOGENESIS OF HCC. METHODS: SIXTY SAMPLES OF HCC AND THE PAIRED ADJACENT LIVER TISSUE, 16 SAMPLES FROM POST-HEPATITIS CIRRHOTIC LIVERS, 5 FROM LIVERS WITH CHRONIC HEPATITIS AND 5 FROM NORMAL LIVERS WERE COLLECTED. EIGHT TSGS FREQUENTLY SILENCED BY HYPERMETHYLATION OF THEIR PROMOTERS IN VARIOUS TYPES OF DIGESTIVE TUMORS WERE SELECTED, INCLUDING APC, RASSF1A, P16, GSTP1, MGMT, DAPK, SOCS-1 AND RIZ1. THE STATUS OF PROMOTER METHYLATION IN THESE 8 GENES WAS INVESTIGATED USING METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION. THE CLINICOPATHOLOGICAL DATA OF HCC WERE ALSO ANALYZED IN ORDER TO EVALUATE THE CLINICAL IMPLICATION OF ABERRANT METHYLATION IN HCC. RESULTS: METHYLATION OF THE 8 TSGS WAS QUITE FREQUENT IN HCC, WITH A METHYLATION RATE OF 95.0% IN RASSF1A, 90.0% IN APC, 73.3% IN GSTP1, 65.0% IN P16, 61.6% IN RIZ1 AND 60.0% IN MGMT. METHYLATION OF THE 6 GENES WAS MORE FREQUENT IN HCC THAN THAT IN ADJACENT TISSUES (P < 0.05). THE METHYLATION RATE OF MGMT, GSTP1 AND RIZ1 IN THE ADJACENT TISSUES WAS 41.6%, 40.0% AND 25.0%, RESPECTIVELY, SIGNIFICANTLY HIGHER THAN THAT IN CIRRHOTIC LIVER (P < 0.05). P16 METHYLATION WAS MORE FREQUENTLY OBSERVED IN HCC IN ELDERLY PATIENTS. THE FREQUENCY OF MGMT METHYLATION WAS TENDED TO BE HIGHER IN GIANT HCC THAN THAT IN THE OTHER TYPES OF HCC. PATIENTS WITH MGMT METHYLATION IN THE TUMOR WERE FOUND TO HAVE A SHORTER DISEASE FREE SURVIVAL. CONCLUSION: DIFFERENT FREQUENCY OF METHYLATION IN HEPATOCELLULAR CARCINOMAS, ADJACENT LIVER TISSUES AND CIRRHOTIC LIVERS IMPLIES THAT EPIGENETIC ALTERATION IN THE HEPATOCELLULAR CARCINOGENESIS MAY BE A GRADUALLY PROGRESSIVE PROCESS. METHYLATION STATUS OF MGMT, GSTP1 AND RIZ1 MAY BE PROMISING IN RISK ASSESSMENT OF HEPATOCELLULAR CARCINOMA AND IN EARLY DIAGNOSIS. FURTHERMORE, MGMT METHYLATION MIGHT BE ALSO USED AS A POTENTIAL PROGNOSTIC BIOMARKER FOR HEPATOCELLULAR CARCINOMA PATIENTS. 2008 17 5274 21 PROMOTER METHYLATION OF P16 AND EDNRB GENE IN LEUKEMIA PATIENTS IN TAIWAN. BOTH EPIGENETIC AND GENETIC ALTERNATIONS ARE INVOLVED IN CANCER FORMATION. IN THIS STUDY, WE HAVE IDENTIFIED THE METHYLATION FREQUENCY OF P16 AND ENDOTHELIN RECEPTOR TYPE B (EDNRB) OF 26 LEUKEMIA PATIENTS AND 8 RANDOMLY SELECTED NORMAL BLOOD DONORS IN TAIWAN. PROMOTER METHYLATION OF P16 WAS DETECTED IN 85% OF ACUTE LYMPHOCYTIC LEUKEMIA (ALL), 83% IN ACUTE MYELOID LEUKEMIA (AML) WHEREAS NO METHYLATION WAS DETECTED IN CHRONIC MYELOID LEUKEMIA (CML) IN BLAST CRISIS. HYPERMETHYLATION OF EDNRB WAS OBSERVED IN 92% OF ALL, 75% AML AND 100% IN CML IN BLAST CRISIS. NO ABERRANT METHYLATION OF P16 AND EDNRB WAS FOUND IN 8 NORMAL BLOOD DONORS. TAKEN TOGETHER, ABERRANT METHYLATION OF P16 AND EDNRB WAS HIGHLY PREVALENT IN LEUKEMIA PATIENTS IN TAIWAN. 2008 18 4905 42 P16INK4A HYPERMETHYLATION IS ASSOCIATED WITH HEPATITIS VIRUS INFECTION, AGE, AND GENDER IN HEPATOCELLULAR CARCINOMA. PURPOSE: THE TUMOR SUPPRESSOR GENE P16INK4A IS MAINLY INACTIVATED BY AN EPIGENETIC CHANGE INVOLVING PROMOTER HYPERMETHYLATION IN HEPATOCARCINOGENESIS. THE POSSIBLE CLINICAL IMPACT OF P16INK4A METHYLATION AND THE POTENTIAL RISK FACTORS FOR THIS EPIGENETIC ALTERATION HAVE NOT BEEN THOROUGHLY INVESTIGATED. EXPERIMENTAL DESIGN: WE STUDIED THE METHYLATION STATUS AND MRNA AND PROTEIN EXPRESSION OF P16INK4A IN 50 HEPATOCELLULAR CARCINOMAS AND CORRESPONDING NONNEOPLASTIC LIVER LESIONS USING METHYLATION-SPECIFIC PCR, REVERSE TRANSCRIPTION-PCR, AND IMMUNOHISTOCHEMICAL TECHNIQUES. RESULTS: P16INK4A HYPERMETHYLATION WAS OBSERVED IN 58% (29 OF 50) OF THE HEPATOCELLULAR CARCINOMAS AND 16% (6 OF 38) OF THE CORRESPONDING CHRONIC HEPATITIS AND CIRRHOSIS TISSUE SAMPLES. P16INK4A METHYLATION WAS SIGNIFICANTLY ASSOCIATED WITH MRNA AND PROTEIN EXPRESSION (P <0.001 AND P=0.003, RESPECTIVELY). ALL OF THE P16INK4A-METHYLATED TUMORS WERE POSITIVE FOR HEPATITIS B VIRUS OR HEPATITIS C VIRUS MARKERS, BUT NONE OF THE VIRUS-NEGATIVE TUMORS EXHIBITED P16INK4A METHYLATION (P=0.006). THE FREQUENCY OF P16INK4A HYPERMETHYLATION TENDED TO BE HIGHER IN HEPATITIS C VIRUS-RELATED TUMORS (23 OF 32, 72%) THAN IN HEPATITIS B VIRUS-RELATED TUMORS (6 OF 13, 46%; P=0.1). ABERRANT METHYLATION OF P16INK4A WAS ALSO RELATED SIGNIFICANTLY TO INCREASING AGE, FEMALE GENDER, AND NORMAL LEVELS OF SERUM PIVKA-II (P=0.02, 0.04, AND 0.04, RESPECTIVELY). NO STATISTICALLY SIGNIFICANT DIFFERENCE IN SURVIVAL WAS OBSERVED BETWEEN PATIENTS WITH P16INK4A HYPERMETHYLATION AND THOSE WITHOUT. CONCLUSIONS: OUR OBSERVATIONS SUGGEST THAT P16INK4A HYPERMETHYLATION MAY CONTRIBUTE TO HEPATOCARCINOGENESIS FROM AN EARLY STAGE AND THAT MULTIPLE RISK FACTORS, SUCH AS VIRAL INFECTIONS, AGE, AND GENDER, MAY BE ASSOCIATED WITH P16INK4A HYPERMETHYLATION IN HEPATOCARCINOGENESIS. 2004 19 817 33 CHARACTERISTIC PATTERNS OF ALTERED DNA METHYLATION PREDICT EMERGENCE OF HUMAN HEPATOCELLULAR CARCINOMA. WE AIMED TO IDENTIFY THE SPECIFIC SUBSET OF TUMOR SUPPRESSOR GENES (TSGS) THAT ARE METHYLATION-SILENCED DURING THE EARLIEST STEPS OF HEPATOCARCINOGENESIS, AND TO FURTHER EVALUATE WHETHER THESE GENES CAN SERVE AS PREDICTIVE BIOMARKERS OF HEPATOCELLULAR CARCINOMA (HCC) EMERGENCE. A TOTAL OF 482 LIVER TISSUES INCLUDING 177 PAIRS OF HCCS AND MATCHED NONTUMOR LIVERS AND 128 LIVER BIOPSIES FROM CHRONIC HEPATITIS C (CHC) PATIENTS WERE ANALYZED FOR QUANTITATIVE METHYLATION ANALYSIS IN 24 TSG PROMOTERS AND THREE MINT LOCI. THE TUMORS WERE CLASSIFIED AS EARLY, LESS-PROGRESSED, AND HIGHLY PROGRESSED HCCS USING HISTOLOGY AND RADIOLOGICAL APPROACHES. A SUBSET OF TSGS THAT HARBORED DISTINCTLY HIGH LEVELS OF METHYLATION IN EARLY HCCS WERE SELECTED. BASED ON THE METHYLATION PROFILES OF THESE GENES, KAPLAN-MEIER ANALYSES WERE PERFORMED TO DETERMINE TIME-TO-HCC OCCURRENCE IN CHC PATIENTS. SUBSEQUENTLY, MULTIVARIATE ANALYSIS WAS PERFORMED USING AGE, GENDER, FIBROSIS STAGE, AND NUMBER OF METHYLATED TSGS AS COVARIATES. AMONG TSGS ANALYZED, A SUBSET OF EIGHT TSGS (HIC1, GSTP1, SOCS1, RASSF1, CDKN2A, APC, RUNX3, AND PRDM2) DEMONSTRATED A DISTINCT CLUSTER BY HIERARCHICAL CLUSTERING AND RECEIVER OPERATING CHARACTERISTIC ANALYSES. THIS SUBSET OF TSGS SHOWED SIGNIFICANTLY HIGHER METHYLATION LEVELS IN THE EARLY HCCS (P < 0.0001). IN THE CHC PATIENTS, METHYLATION FREQUENCIES IN THESE TSGS WERE ASSOCIATED WITH SHORTER TIME-TO-HCC OCCURRENCE (P < 0.0001), AND NUMBER OF METHYLATED GENES WAS AN INDEPENDENT RISK FACTOR FOR HCC (HAZARD RATIO = 5.21, 95% CONFIDENCE INTERVAL = 2.25-11.76, P = 0.0002). CONCLUSION: EPIGENETIC INACTIVATION OF A SUBSET OF TSGS PLAYS A CRITICAL ROLE IN THE EARLIEST STEPS OF HEPATOCARCINOGENESIS. FURTHERMORE, EPIGENETIC INACTIVATION OF THESE GENES IN CHC PROVIDES A PROGNOSTIC VALUE FOR DETERMINING THE RISK FOR DEVELOPING HCC LATER IN LIFE. 2012 20 2960 31 GENETIC AND EPIGENETIC MARKERS IN THE EVALUATION OF PANCREATIC MASSES. BACKGROUND: METHYLATION MARKERS HAVE SHOWN PROMISE IN THE EARLY DIAGNOSIS OF PANCREATIC CARCINOMA. THE AIM OF THIS STUDY WAS TO ASSESS THE DIAGNOSTIC UTILITY OF HYPERMETHYLATION STATUS OF CANDIDATE GENES IN COMBINATION WITH KRAS MUTATION DETECTION IN THE EVALUATION OF PANCREATIC MASSES. EXPERIMENTAL DESIGN: SIXTY-ONE FINE NEEDLE ASPIRATES OF PANCREATIC MASSES (43 PANCREATIC ADENOCARCINOMAS AND 18 CHRONIC PANCREATITIS) WERE STUDIED. METHYLATION STATUS OF HRH2, EN1, SPARC, CDH13 AND APC WERE ANALYSED USING MELTING CURVE ANALYSIS AFTER DNA BISULFITE TREATMENT. KRAS MUTATIONS WERE ALSO ANALYSED. RESULTS: THE METHYLATION PANEL HAD A SENSITIVITY OF 73% (27 OF 37, CI 95% 56 TO 86%) AND A SPECIFICITY OF 100% WHENEVER TWO OR MORE PROMOTERS WERE FOUND HYPERMETHYLATED. KRAS MUTATIONS SHOWED A SENSITIVITY OF 77% (33 OF 43, CI 95% 62 TO 88%) AND A SPECIFICITY OF 100%. BOTH MOLECULAR ANALYSES ADDED USEFUL INFORMATION TO CYTOLOGY BY INCREASING THE NUMBER OF INFORMATIVE CASES. WHEN GENETIC AND EPIGENETIC ANALYSES WERE COMBINED SENSITIVITY WAS 84% (36 OF 43 CI 95% 69 TO 93%) MAINTAINING A 100% SPECIFICITY. CONCLUSIONS: ANALYSIS OF HYPERMETHYLATION STATUS OF A PANEL OF GENES AND KRAS MUTATION DETECTION OFFER A SIMILAR DIAGNOSTIC YIELD IN THE EVALUATION OF PANCREATIC MASSES. THE COMBINED MOLECULAR ANALYSIS INCREASES THE NUMBER OF INFORMATIVE CASES WITHOUT DIMINISHING SPECIFICITY. 2013