1 6770 136 [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 2 4245 41 METHYLATION STATUS OF DDIT3 GENE IN CHRONIC MYELOID LEUKEMIA. BACKGROUND: DNA-DAMAGE-INDUCIBLE TRANSCRIPT 3 (DDIT3), A CANDIDATE TUMOR SUPPRESSOR GENE (TSG), HAS BEEN FOUND INVOLVED IN THE REGULATION OF CELLULAR GROWTH AND DIFFERENTIATION. THE EPIGENETIC CHANGES OF TSGS ARE RECENTLY RECOGNIZED AS AN ABNORMAL MECHANISM CONTRIBUTING TO THE DEVELOPMENT OF CHRONIC MYELOID LEUKEMIA (CML). THE AIM OF THIS STUDY WAS TO INVESTIGATE THE METHYLATION STATUS OF DDIT3 GENE IN CML PATIENTS. METHODS: THE METHYLATION STATUS OF DDIT3 PROMOTER WAS DETECTED IN THE BONE MARROW MONONUCLEAR CELLS FROM 53 PATIENTS WITH CML USING METHYLATION-SPECIFIC PCR (MSP). THE EXPRESSION LEVELS OF DDIT3 AND BCR/ABL TRANSCRIPT WERE DETERMINED BY REAL-TIME QUANTITATIVE PCR (RQ-PCR). CLINICAL DATA OF THESE PATIENTS WERE COLLECTED AND ANALYZED. RESULTS: THE ABERRANT METHYLATION OF DDIT3 GENE PROMOTER WAS FOUND IN 35 OF 53 (66%) CML CASES. CORRELATION WAS NOT FOUND BETWEEN DDIT3 PROMOTER HYPERMETHYLATION AND THE AGE, SEX, HEMOGLOBIN CONCENTRATION, PLATELET COUNTS, CHROMOSOMAL ABNORMALITIES, BCR/ABL TRANSCRIPT, AND STAGING OF CML PATIENTS (P > 0.05), BUT FOUND BETWEEN DDIT3 PROMOTER HYPERMETHYLATION AND WBC COUNTS OF CML CASES (R = 0.781, P < 0.001). THE LEVEL OF DDIT3 TRANSCRIPT IN CML PATIENTS WAS SIGNIFICANTLY LOWER THAN THAT IN CONTROLS (MEDIAN 3.28 VS 19.69, P < 0.001), HOWEVER, THERE WAS NO DIFFERENCE IN THE LEVEL OF DDIT3 TRANSCRIPT BETWEEN METHYLATION-POSITIVE CML CASES (0.05-65.32, MEDIAN 2.13) AND METHYLATION- NEGATIVE CML CASES (0.12-126.04, MEDIAN 3.92) (P > 0.05). CONCLUSION: OUR RESULTS DEMONSTRATE THAT ABERRANT METHYLATION OF DDIT3 OCCURS IN CML FREQUENTLY. 2010 3 817 53 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 4 156 41 ABERRANT METHYLATION OF THE DEATH-ASSOCIATED PROTEIN KINASE 1 (DAPK1) CPG ISLAND IN CHRONIC MYELOID LEUKEMIA. THE DEATH-ASSOCIATED PROTEIN KINASE 1 (DAPK1) GENE IS A CANDIDATE TUMOR SUPPRESSOR (TSG) AND THE ABNORMAL METHYLATION OF DAPK1 GENE HAS BEEN FOUND IN MANY CARCINOMAS. THE EPIGENETIC CHANGES OF TSGS ARE NOW RECOGNIZED AS A MECHANISM CONTRIBUTING TO THE DEVELOPMENT OF CHRONIC MYELOID LEUKEMIA (CML). TO CLARIFY THE ROLE OF DAPK1 IN CML, WE EXAMINED THE METHYLATION STATUS OF DAPK1 IN 49 PATIENTS WITH CML USING METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION. THE ABERRANT METHYLATION OF THE DAPK1 GENE WAS FOUND IN 25 OF 49 (51.0%) CML CASES, NOT IN ALL CONTROLS. NO CORRELATION WAS FOUND BETWEEN DAPK1 GENE METHYLATION AND THE AGE, HEMATOLOGIC PARAMETERS, CHROMOSOMAL ABNORMALITIES, THE TYPES AND LEVELS OF BCR/ABL TRANSCRIPTS OF CML PATIENTS. HOWEVER, CORRELATION COULD BE OBSERVED BETWEEN THE SEX AND THE STATUS OF DAPK1 METHYLATION IN CML PATIENTS (R = 0.374, P = 0.008). FURTHERMORE, THERE WAS A SIGNIFICANT CORRELATION BETWEEN DAPK1 METHYLATION AND THE STAGES OF CML (R = 0.354, P = 0.013). THE CML PATIENTS IN ACCELERATED PHASE (AP) AND BLAST CRISIS (BC) HAD HIGHER FREQUENCY OF DAPK1 METHYLATION THAN THOSE IN CHRONIC PHASE (CP) (75.0% VS. 34.5%) (CHI(2) = 7.776, P = 0.005). IN ONE PATIENT, THE STATUS OF DAPK1 METHYLATION BECAME POSITIVE ON THE TRANSITION FROM CP TO AP AND BC. THESE RESULTS SUGGESTED THAT DAPK1 PROMOTER METHYLATION MIGHT PLAY A SIGNIFICANT ROLE IN THE PROGRESSION OF CML. 2009 5 1342 62 DETECTING ABNORMAL METHYLATION OF TUMOR SUPPRESSOR GENES GSTP1, P16, RIZ1, AND RASSF1A IN HEPATOCELLULAR CARCINOMA AND ITS CLINICAL SIGNIFICANCE. HEPATOCELLULAR CARCINOMA (HCC) HAS A HIGH RATE OF MORTALITY. FURTHER STUDIES INTO EPIGENETIC CHANGES IN HCC, PARTICULARLY THE ABNORMAL METHYLATION OF TUMOR SUPPRESSOR GENES (TSGS), ARE REQUIRED, SINCE THESE CHANGES MAY PROVIDE NOVEL BIOMARKERS FOR EARLY SCREENING AND DIAGNOSIS OF HCC. BY USING METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION (MSP), THE PRESENT STUDY DETECTED THE METHYLATION STATUS IN THE PROMOTER REGION OF 4 CANDIDATE TSGS, GSTP1, P16, RIZ1, AND RASSF1A, RESPECTIVELY, IN 35 PAIRED HCC AND TUMOR-ADJACENT LIVER TISSUES IN ADDITION TO 20 NORMAL LIVER TISSUES. THEIR EFFECT ON THE INITIATION AND PROGRESSION OF HCC WAS ALSO INVESTIGATED BY ANALYZING THE CLINICOPATHOLOGICAL DATA. THE RESULTS OF THE PRESENT STUDY REVEALED THAT THE METHYLATION LEVEL OF RIZ1 AND GSTP1 GENES IN HCC WAS SIGNIFICANTLY INCREASED COMPARED WITH THAT IN THE ADJACENT TISSUES (P<0.01) AND THE NORMAL LIVER TISSUES (P<0.01). THE METHYLATION FREQUENCY OF P16 AND RASSF1A GENES WAS NOT SIGNIFICANTLY INCREASED COMPARED WITH THAT OBSERVED IN THE ADJACENT TISSUES (P>0.05) BUT WAS SIGNIFICANTLY INCREASED COMPARED WITH THE NORMAL TISSUES (P<0.01). IN HCC TISSUES, THE METHYLATION FREQUENCY OF THE GSTP1 GENE IN TUMORS WITH CAPSULAR INVASION WAS SIGNIFICANTLY INCREASED COMPARED WITH THAT IN TUMORS WITHOUT CAPSULAR INVASION (P<0.05). THE METHYLATION FREQUENCY OF P16 GENE IN HEPATITIS B SURFACE ANTIGEN (HBSAG)-POSITIVE HCC PATIENTS WAS SIGNIFICANTLY INCREASED COMPARED WITH THAT IN HBSAG-NEGATIVE PATIENTS (P<0.05). THE METHYLATION STATUS OF RIZ1 AND RASSF1A GENES WAS NOT SIGNIFICANTLY CORRELATED WITH THE CLINICOPATHOLOGICAL DATA (P>0.05). PREVIOUS STUDIES HAVE DEMONSTRATED THAT THE METHYLATION STATUS OF RIZ1 AND GSTP1 GENES IS HCC-SPECIFIC, AND THUS MAY BE USED AS A BIOMARKER TO ASSIST THE CLINICAL DIAGNOSIS OF HCC. WHILE THE METHYLATION OF GSTP1 GENE PROMOTER MAY ASSOCIATE WITH THE INVASIVENESS OF HCC, CHRONIC HEPATITIS B VIRUS INFECTION MAY BE THE CAUSE OF METHYLATION-INDUCED P16 INACTIVATION. 2015 6 401 49 ANALYSIS OF ABERRANT METHYLATION ON PROMOTER SEQUENCES OF TUMOR SUPPRESSOR GENES AND TOTAL DNA IN SPUTUM SAMPLES: A PROMISING TOOL FOR EARLY DETECTION OF COPD AND LUNG CANCER IN SMOKERS. BACKGROUND: CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) IS A DISORDER ASSOCIATED TO CIGARETTE SMOKE AND LUNG CANCER (LC). SINCE EPIGENETIC CHANGES IN ONCOGENES AND TUMOR SUPPRESSOR GENES (TSGS) ARE CLEARLY IMPORTANT IN THE DEVELOPMENT OF LC. IN THIS STUDY, WE HYPOTHESIZE THAT TOBACCO SMOKERS ARE SUSCEPTIBLE FOR METHYLATION IN THE PROMOTER REGION OF TSGS IN AIRWAY EPITHELIAL CELLS WHEN COMPARED WITH NON-SMOKER SUBJECTS. THE PURPOSE OF THIS STUDY WAS TO INVESTIGATE THE USEFULNESS OF DETECTION OF GENES PROMOTER METHYLATION IN SPUTUM SPECIMENS, AS A COMPLEMENTARY TOOL TO IDENTIFY LC BIOMARKERS AMONG SMOKERS WITH EARLY COPD. METHODS: WE DETERMINED THE AMOUNT OF DNA IN INDUCED SPUTUM FROM PATIENTS WITH COPD (N = 23), LC (N = 26), AS WELL AS IN HEALTHY SUBJECTS (CTR) (N = 33), USING A COMMERCIAL KIT FOR DNA PURIFICATION, FOLLOWED BY ABSORBANCE MEASUREMENT AT 260 NM. THE FREQUENCY OF CDKN2A, CDH1 AND MGMT PROMOTER METHYLATION IN THE SAME GROUPS WAS DETERMINED BY METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION (MSP). THE FISHER'S EXACT TEST WAS EMPLOYED TO COMPARE FREQUENCY OF RESULTS BETWEEN DIFFERENT GROUPS. RESULTS: DNA CONCENTRATION WAS 7.4 AND 5.8 TIMES HIGHER IN LC AND COPD COMPARED TO THE (CTR) (P < 0.0001), RESPECTIVELY. METHYLATION STATUS OF CDKN2A AND MGMT WAS SIGNIFICANTLY HIGHER IN COPD AND LC PATIENTS COMPARED WITH CTR GROUP (P < 0.0001). FREQUENCY OF CDH1 METHYLATION ONLY SHOWED A STATISTICALLY SIGNIFICANT DIFFERENCE BETWEEN LC PATIENTS AND CTR GROUP (P < 0.05). CONCLUSIONS: WE PROVIDE EVIDENCE THAT ABERRANT METHYLATION OF TSGS IN SAMPLES OF INDUCED SPUTUM IS A USEFUL TOOL FOR EARLY DIAGNOSTIC OF LUNG DISEASES (LC AND COPD) IN SMOKER SUBJECTS. VIRTUAL SLIDES: THE ABSTRACT MUST FINISH WITH THE FOLLOWING TEXT: VIRTUAL SLIDES THE VIRTUAL SLIDE(S) FOR THIS ARTICLE CAN BE FOUND HERE: HTTP://WWW.DIAGNOSTICPATHOLOGY.DIAGNOMX.EU/VS/1127865005664160. 2012 7 5357 39 REACTIVE OXYGEN SPECIES INDUCE EPIGENETIC INSTABILITY THROUGH THE FORMATION OF 8-HYDROXYDEOXYGUANOSINE IN HUMAN HEPATOCARCINOGENESIS. CHRONIC HEPATITIS C (CHC) TRIGGERS OXIDATIVE STRESS AND CONTRIBUTES TO THE EMERGENCE OF HEPATOCELLULAR CARCINOMA (HCC). WE PREVIOUSLY REPORTED THAT TUMOR SUPPRESSOR GENE (TSG) METHYLATION IS A CRITICAL FACTOR DURING THE EARLY STAGES OF HEPATOCARCINOGENESIS. IN THIS STUDY, WE CLARIFY THE ASSOCIATION BETWEEN OXIDATIVE STRESS AND EPIGENETIC ALTERATIONS DURING HEPATOCARCINOGENESIS. WE EXAMINED DNA OXIDATION AND METHYLATION PROFILES IN 128 LIVER BIOPSY SAMPLES FROM CHC PATIENTS. THE DNA OXIDATION AND METHYLATED TSG NUMBERS WERE QUANTIFIED USING IMMUNOHISTOCHEMICAL ANALYSIS OF 8-HYDROXYDEOXYGUANOSINE (8-OHDG) AND QUANTITATIVE PCR FOR 11 TSGS, RESPECTIVELY. THE QUANTITATIVE CHROMATIN IMMUNOPRECIPITATION-PCR (CHIP-QPCR) ASSAY IN HEPG2 AND FETAL LIVER HC CELLS TREATED WITH H2O2 WAS USED TO QUANTIFY TRIMETHYL-H3K4, ACETYLATED-H4K16 (AN ACTIVE CHROMATIN MARKER), TRIMETHYL-H3K27 (A REPRESSIVE CHROMATIN MARKER) AND 8-OHDG. WE ANALYZED 30 PROMOTERS OF 25 DIFFERENT TSGS BY QPCR. THE HIGH LEVELS OF 8-OHDG WAS THE ONLY VARIABLE THAT WAS SIGNIFICANTLY ASSOCIATED WITH THE INCREASED NUMBER OF METHYLATED TSGS IN CHC (P < 0.0001). THE CHIP-QPCR REVEALED THAT AFTER H2O2 TREATMENT OF THE CELL LINES, THE 8-OHDG-BOUND PROMOTERS SHOWED A MODIFICATION FROM AN ACTIVE CHROMATIN (TRIMETHYL-H3K4 AND ACETYLATED-H4K16 DOMINANT) TO A REPRESSIVE CHROMATIN (TRIMETHYL-H3K27 DOMINANT) STATUS. WE CONCLUDE THAT OXIDATIVE STRESS ALTERS THE CHROMATIN STATUS, WHICH LEADS TO ABNORMAL METHYLATION OF TSGS, AND CONTRIBUTES TO HEPATOCARCINOGENESIS IN CHC PATIENTS. 2013 8 4903 39 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 9 2842 46 FREQUENT CONCOMITANT EPIGENETIC SILENCING OF SOX1 AND SECRETED FRIZZLED-RELATED PROTEINS (SFRPS) IN HUMAN HEPATOCELLULAR CARCINOMA. BACKGROUND AND AIM: EXCEPT FOR GENETIC MUTATIONS, EPIGENETIC CHANGES ARE ALSO INVOLVED IN THE DEVELOPMENT OF HUMAN CANCERS. RECENTLY, WE HAVE IDENTIFIED SOX1, SRY (SEX DETERMINING REGION Y)-BOX 1, IS HYPERMETHYLATED IN CERVICAL CANCER AND OVARIAN CANCER. THEREFORE, WE INVESTIGATED WHETHER PROMOTER HYPERMETHYLATION OF SOX1 IS COMMON IN HEPATOCELLULAR CARCINOMA (HCC). METHODS: WE USED METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION (MS-PCR) AND BISULFITE SEQUENCING TO ANALYZE THE METHYALTION LEVEL OF THE SOX1 PROMOTER IN SEVEN HCC CELL LINES, 54 CLINICAL HCCS, 42 CIRRHOTIC LIVERS, 21 LIVERS WITH CHRONIC HEPATITIS, AND 15 CONTROL LIVERS. THEN, WE EMPLOYED QUANTITATIVE MS-PCR (QMSP) TO VALIDATE IN AN INDEPENDENT SET OF SAMPLES (60 PAIRED HCCS AND 30 CONTROL LIVERS). FINALLY, WE USED LUCIFERASE REPORTER AND COLONY FORMATION ASSAY TO CHECK THE EFFECT OF SOX1 IN HCC. RESULTS: PROMOTER METHYLATION OF SOX1 WAS SIGNIFICANTLY FREQUENT IN HCC CELL LINES AND CLINICAL HCCS, CIRRHOTIC LIVERS, BUT NOT IN CONTROL LIVERS (P < 0.0001). THERE IS A SIGNIFICANT CORRELATION BETWEEN DOWNREGULATION OF SOX1 EXPRESSION AND PROMOTER METHYLATION. QMSP RESULTS CONFIRMED THAT PROMOTER HYPERMETHYLATION OF SOX1 IS SIGNIFICANTLY MORE FREQUENT IN HCCS THAN CONTROL LIVERS (P < 0.0001). THE FREQUENCY OF SOX1 METHYLATION IN PATIENTS WITH SECRETED FRIZZLED-RELATED PROTEINS (SFRPS) METHYLATION IS SIGNIFICANTLY HIGHER THAN IN PATIENTS WITHOUT SFRPS METHYLATION (P < 0.0001). FURTHERMORE, ECTOPIC EXPRESSION OF SOX1 COULD SUPPRESS T-CELL FACTOR-DEPENDENT TRANSCRIPTIONAL ACTIVITY AND COLONY FORMATION NUMBER IN HCCS. CONCLUSIONS: CONCOMITANT EPIGENETIC SILENCING OF SOX1 AND SFRPS THROUGH PROMOTER HYPERMETHYLATION IS FREQUENT IN HCCS, AND THIS MIGHT CONTRIBUTE TO ABNORMAL ACTIVATION OF CANONICAL WNT SIGNAL PATHWAY. 2013 10 4231 43 METHYLATION OF PROTOCADHERIN 10, A NOVEL TUMOR SUPPRESSOR, IS ASSOCIATED WITH POOR PROGNOSIS IN PATIENTS WITH GASTRIC CANCER. BACKGROUND & AIMS: BY USING METHYLATION-SENSITIVE REPRESENTATIONAL DIFFERENCE ANALYSIS, WE IDENTIFIED PROTOCADHERIN 10 (PCDH10), A GENE THAT ENCODES A PROTOCADHERIN AND IS SILENCED IN A TUMOR-SPECIFIC MANNER. WE ANALYZED ITS EPIGENETIC INACTIVATION, BIOLOGICAL EFFECTS, AND PROGNOSTIC SIGNIFICANCE IN GASTRIC CANCER. METHODS: METHYLATION STATUS WAS EVALUATED BY COMBINED BISULFITE RESTRICTION ANALYSIS AND BISULFITE SEQUENCING. THE EFFECTS OF PCDH10 RE-EXPRESSION WERE DETERMINED IN GROWTH, APOPTOSIS, PROLIFERATION, AND INVASION ASSAYS. PCDH10 TARGET GENES WERE IDENTIFIED BY COMPLEMENTARY DNA MICROARRAY ANALYSIS. RESULTS: PCDH10 WAS SILENCED OR DOWN-REGULATED IN 94% (16 OF 17) OF GASTRIC CANCER CELL LINES; EXPRESSION LEVELS WERE RESTORED BY EXPOSURE TO DEMETHYLATING AGENTS. RE-EXPRESSION OF PCDH10 IN MKN45 GASTRIC CANCER CELLS REDUCED COLONY FORMATION IN VITRO AND TUMOR GROWTH IN MICE; IT ALSO INHIBITED CELL PROLIFERATION (P < .01), INDUCED CELL APOPTOSIS (P < .001), AND REPRESSED CELL INVASION (P < .05), UP-REGULATING THE PRO-APOPTOSIS GENES FAS, CASPASE 8, JUN, AND CDKN1A; THE ANTIPROLIFERATION GENE FGFR; AND THE ANTI-INVASION GENE HTATIP2. PCDH10 METHYLATION WAS DETECTED IN 82% (85 OF 104) OF GASTRIC TUMORS COMPARED WITH 37% (38 OF 104) OF PAIRED NONTUMOR TISSUES (P < .0001). IN THE LATTER, PCDH10 METHYLATION WAS HIGHER IN PRECANCEROUS LESIONS (27 OF 45; 60%) THAN IN CHRONIC GASTRITIS SAMPLES (11 OF 59; 19%) (P < .0001). AFTER A MEDIAN FOLLOW-UP PERIOD OF 16.8 MONTHS, MULTIVARIATE ANALYSIS REVEALED THAT PATIENTS WITH PCDH10 METHYLATION IN ADJACENT NONTUMOR AREAS HAD A SIGNIFICANT DECREASE IN OVERALL SURVIVAL. KAPLAN-MEIER SURVIVAL CURVES SHOWED THAT PCDH10 METHYLATION WAS ASSOCIATED SIGNIFICANTLY WITH SHORTENED SURVIVAL IN STAGE I-III GASTRIC CANCER PATIENTS. CONCLUSIONS: PCDH10 IS A GASTRIC TUMOR SUPPRESSOR; ITS METHYLATION AT EARLY STAGES OF GASTRIC CARCINOGENESIS IS AN INDEPENDENT PROGNOSTIC FACTOR. 2009 11 4246 48 METHYLATION STATUS OF THE T-CADHERIN GENE PROMOTOR IN PERIPHERAL BLOOD MONONUCLEAR CELLS IS ASSOCIATED WITH HBV-RELATED HEPATOCELLULAR CARCINOMA PROGRESSION. DNA METHYLATION IS ONE OF THE EPIGENETIC MECHANISMS TO REGULATE GENE EXPRESSION AND FREQUENTLY OCCURS IN HUMAN CANCER CELLS. T-CADHERIN (CDH13) IS A NEW MEMBER OF THE CADHERIN SUPERFAMILY AND POSSESSES MULTIPLE FUNCTIONS. OUR STUDY INCLUDED 26 NORMAL CONTROLS (NCS), 65 CHRONIC HEPATITIS B PATIENTS (CHB), 14 LIVER CIRRHOSIS PATIENTS (LC) AND 157 HEPATOCELLULAR CARCINOMA PATIENTS (HCC). WE MAINLY FOCUSED ON THE MRNA EXPRESSION AND METHYLATION STATUS OF CDH13 IN PERIPHERAL BLOOD MONONUCLEAR CELLS (PBMCS), WHICH WERE DETECTED BY SEMI-QUANTITATIVE REAL-TIME POLYMERASE CHAIN REACTION (RT-QPCR) AND METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION (MSP) RESPECTIVELY. THE CDH13 MRNA LEVEL WAS LOWER IN HCC, ESPECIALLY IN EARLY-STAGE OF HCC THAN IN NCS AND CHB GROUPS (P < 0.05). METHYLATION FREQUENCY OF THE CDH13 PROMOTER WAS SIGNIFICANTLY HIGHER IN HCC PATIENTS THAN IN THE NCS AND CHB GROUPS (67.52 % VS 0.00 %, P < 0.001, 67.52 % VS 52.31 %, P < 0.05, RESPECTIVELY). CDH13 MRNA LEVEL WAS SIGNIFICANTLY AND RELATIVELY LOWER IN METHYLATED GROUPS THAN IN UNMETHYLATED GROUPS AMONG THE WHOLE PARTICIPANTS. THE METHYLATION LEVEL OF CDH13 PROMOTER IN HCC MIGHT BE INFLUENCED OR PARTLY INFLUENCED BY SOME CRITICAL FACTORS SUCH AS TBIL, ALB AND AFP (P < 0.05). AS AN IMPORTANT FACTOR IN SIGNALING PATHWAY REGULATING BY CDH13 TO PROMOTE CARCINOGENESIS, JNK LEVEL WAS SIGNIFICANTLY HIGHER IN HCC WHICH HAD A HIGHER METHYLATION FREQUENCY THAN IN NCS, CHB AND LC (P < 0.05). FURTHERMORE, THE COMBINATION OF THE METHYLATED CDH13 LEVEL AND AFP LEVEL SHOWED A BETTER SCORE: AUC = 0.796 (SE = 0.031, 95 %CI 0.735-0.857; P < 0.001) IN MALE AND AUC = 0.832 (SE = 0.057, 95 %CI 0.721-0.944; P < 0.001) IN FEMALE COMPARED TO AFP ALONE FOR DIAGNOSING HCC FROM NCS, CHB AND LC. THE METHYLATION OF CDH13 PROMOTER WAS AN INDEPENDENT PREDICTOR FOR ASSESSING THE PROGNOSIS OF HCC PATIENTS (R=-1.378 P < 0.05). IN CONCLUSION, HYPERMETHYLATION OF CDH13 IN PBMCS WAS ASSOCIATED WITH THE UNDEREXPRESSION OF MRNA AND THE HIGH RISK OF HCC. THE METHYLATION STATUS OF THE CDH13 PROMOTER IN PBMCS WAS A POTENTIAL NONINVASIVE BIOMARKER TO PREDICT THE PROGNOSIS OF HCC PATIENTS. 2020 12 3294 43 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 13 1495 33 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 14 159 51 ABERRANT PROMOTER HYPERMETHYLATION OF MULTIPLE GENES IN GALLBLADDER CARCINOMA AND CHRONIC CHOLECYSTITIS. PURPOSE: ABERRANT METHYLATION OF 5' GENE PROMOTER REGIONS IS AN EPIGENETIC PHENOMENON THAT IS A MAJOR MECHANISM FOR SILENCING OF TUMOR SUPPRESSOR GENES IN MANY CANCER TYPES. THERE IS LIMITED INFORMATION ABOUT THE MOLECULAR CHANGES INVOLVED IN THE PATHOGENESIS OF GALLBLADDER CARCINOMA (GBC), INCLUDING METHYLATION STATUS. EXPERIMENTAL DESIGN: WE INVESTIGATED THE ABERRANT PROMOTER METHYLATION PROFILE OF 24 KNOWN OR SUSPECTED TUMOR SUPPRESSOR GENES IN 50 GBCS AND COMPARED THOSE RESULTS WITH THE FINDINGS IN 25 CHRONIC CHOLECYSTITIS (CC) SPECIMENS WITHOUT CANCER. THE METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION AND COMBINED RESTRICTION ANALYSIS METHODS WERE USED TO DETECT METHYLATION, AND THE RESULTS WERE CONFIRMED BY SEQUENCING OF CLONED POLYMERASE CHAIN REACTION PRODUCTS. RESULTS: IN GBC, GENE METHYLATION FREQUENCIES VARIED FROM 0% TO 80%. TEN GENES DEMONSTRATED RELATIVELY HIGH FREQUENCIES OF ABERRANT METHYLATION: SHP1 (80%), 3-OST-2 (72%), CDH13 (44%), P15INK4B (44%), CDH1 (38%), RUNX3 (32%), APC (30%), RIZ1 (26%), P16INK4A (24%), AND HPP1 (20%). EIGHT GENES (P73, RARBETA2, SOCS-1, DAPK, DCR2, DCR1, HIN1, AND CHFR) SHOWED LOW FREQUENCIES (2-14%) OF METHYLATION, AND NO METHYLATION OF THE REMAINING SIX GENES (TIMP-3, P57, RASSF1A, CRBP1, SYK, AND NORE1) WAS DETECTED. IN CC, METHYLATION WAS DETECTED FOR SEVEN GENES: SHP1 (88%), P15INK4B (28%), 3-OST-2 (12%), CDH1 (12%), CDH13 (8%), DCR2 (4%), AND P16INK4A (4%). SIGNIFICANTLY HIGHER FREQUENCIES OF METHYLATION IN GBC COMPARED WITH CC WERE DETECTED FOR EIGHT GENES (3-OST-2, CDH13, CDH1, RUNX3, APC, RIZ1, P16INK4A, AND HPP1). OF THOSE, FOUR GENES SHOWED FREQUENT METHYLATION (>30%) IN GBCS. THE MEAN METHYLATION INDEX, AN EXPRESSION OF THE AMOUNT OF METHYLATED GENES BY CASE, WAS SIGNIFICANTLY HIGHER IN GBC (0.196 +/- 0.013) COMPARED WITH CC (0.065 +/- 0.008; P < 0.001). CONCLUSIONS: OUR STUDY CONSTITUTES THE MOST COMPREHENSIVE METHYLATION PROFILE REPORT AVAILABLE IN GBC AND DEMONSTRATES THAT THIS NEOPLASM HAS A DISTINCT PATTERN OF ABNORMAL GENE METHYLATION. WHEREAS GALLBLADDERS FROM HEALTHY INDIVIDUAL WERE NOT AVAILABLE, OUR FINDING OF METHYLATION IN CC CASES WITHOUT CANCER SUGGESTS THAT THIS PHENOMENON REPRESENTS AN EARLY EVENT IN THE PATHOGENESIS OF GBC. 2004 15 2942 35 GENETIC AND EPIGENETIC ALTERATIONS OF LTF AT 3P21.3 IN NASOPHARYNGEAL CARCINOMA. TO INVESTIGATE THE ROLES OF LACTOTRANSFERRIN GENE (LTF, ALSO REFERRED TO AS THE LACTOFERRIN GENE, LF), LOCATED AT 3P21.3 WITHIN THE COMMON MINIMAL DELETION REGION, IN THE PATHOGENESIS OF NASOPHARYNGEAL CARCINOMA (NPC), WE FIRST DETECTED ITS EXPRESSION LEVEL IN 33 PRIMARY NPC TISSUES AND 15 CHRONIC NASOPHARYNGITIS TISSUES. ABSENT EXPRESSION OR DOWNREGULATION OF LTF WERE OBSERVED IN 76% (25 OF 33) OF PRIMARY NPC TISSUES. WE FURTHER FOUND THAT 25% (5 OF 20) OF NPC SPECIMENS HAD LOSS OF HETEROZYGOSITY (LOH) AT THE LTF LOCUS. LTF MUTATION ASSESSED BY POLYMERASE CHAIN REACTION SINGLE-STRAND CONFORMATION POLYMORPHISM (PCR-SSCP) AND DNA SEQUENCING WAS NOTED IN 30% (6 OF 20) OF PRIMARY NPC TISSUES. IN ADDITION, HYPER-METHYLATION OF LTF PROMOTER REGION WAS FOUND IN 63.6% (21 OF 33) OF PRIMARY NPC SAMPLES BUT NOT IN CHRONIC NASOPHARYNGITIS TISSUES. THE LTF TRANSCRIPTS IN NPC CELL LINES INCREASED UPON TREATMENT WITH THE DEMETHYLATION COMPOUND, 5-AZA-2-DEOXYCYTIDINE. IN CONCLUSION, OUR DATA INDICATE THAT TWO-HIT SILENCING OF LTF THROUGH GENETIC AND EPIGENETIC CHANGES MAY BE A COMMON AND IMPORTANT EVENT IN THE CARCINOGENESIS OF NPC. 2006 16 5274 20 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 17 2440 27 EPIGENETIC SILENCING OF TUMOR SUPPRESSOR LONG NON-CODING RNA BM742401 IN CHRONIC LYMPHOCYTIC LEUKEMIA. BM742401 IS A TUMOR SUPPRESSOR LNCRNA DOWNREGULATED IN GASTRIC CANCER. AS THE PROMOTER REGION AND THE ENTIRE TRANSCRIPT ARE EMBEDDED IN A CPG ISLAND, WE POSTULATED THAT BM742401 IS A TUMOR SUPPRESSOR LNCRNA INACTIVATED BY DNA METHYLATION IN CHRONIC LYMPHOCYTIC LEUKEMIA (CLL). THE PROMOTER OF BM742401 WAS UNMETHYLATED IN NORMAL CONTROLS INCLUDING THREE EACH OF NORMAL BONE MARROW, PERIPHERAL BLOOD BUFFY COATS, AND CD19-SORTED PERIPHERAL B-CELLS, BUT METHYLATED IN FOUR (57.1%) CLL CELL LINES. METHYLATION OF BM742401 CORRELATED INVERSELY WITH EXPRESSION. IN THE COMPLETELY METHYLATED WAC3CD5+ CLL CELLS, 5-AZA-2'-DEOXYCYTIDINE TREATMENT LED TO PROMOTER DEMETHYLATION AND RE-EXPRESSION OF BM742401 TRANSCRIPT. FUNCTIONALLY, STABLE OVEREXPRESSION OF BM742401 RESULTED IN INHIBITION OF CELLULAR PROLIFERATION AND ENHANCED APOPTOSIS THROUGH CASPASE-9-DEPENDENT INTRINSIC BUT NOT CASPASE-8-DEPENDENT EXTRINSIC APOPTOSIS PATHWAY, SUGGESTING A TUMOR SUPPRESSOR ROLE OF BM742401 IN CLL. IN PRIMARY CLL SAMPLES, METHYLATION OF BM742401 WAS DETECTED IN 43/98 (43.9%) OF PATIENTS. MOREOVER, AMONG CLL PATIENTS WITH STANDARD-RISK CYTOGENETIC ABERRATIONS, METHYLATION OF BM742401 CORRELATED WITH ADVANCED RAI STAGE (>/= STAGE 2)(P = 0.002). FURTHERMORE, BM742401 METHYLATION WAS ASSOCIATED WITH MIR-129-2 METHYLATION (P = 0.05). BM742401 IS A TUMOR SUPPRESSOR LNCRNA FREQUENTLY METHYLATED IN CLL. THE MECHANISM OF BM742401 AS A TUMOR SUPPRESSOR WARRANTS FURTHER STUDIES. 2016 18 2847 36 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 19 2126 42 EPIGENETIC INACTIVATION OF MIR-34B/C IN ADDITION TO MIR-34A AND DAPK1 IN CHRONIC LYMPHOCYTIC LEUKEMIA. BACKGROUND: TP53 MUTATION/DELETION IS UNCOMMON IN CHRONIC LYMPHOCYTIC LEUKEMIA (CLL). WE POSTULATED THAT COMPONENTS OF TP53-CENTERED TUMOR SUPPRESSOR NETWORK, MIR-34B/C, IN ADDITION TO DAPK1 AND MIR-34A MIGHT BE INACTIVATED BY DNA HYPERMETHYLATION. MOREOVER, WE TESTED IF MIR-34B/C METHYLATION MIGHT CORRELATE WITH MIR-203 OR MIR-124-1 METHYLATION IN CLL. METHODS: MIR-34B/C, MIR-34A AND DAPK1 METHYLATION WAS STUDIED IN 11 NORMAL CONTROLS, 7 CLL CELL LINES, AND 78 DIAGNOSTIC CLL SAMPLES BY METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION. MEC-1 CELLS WERE TREATED WITH 5-AZA-2'-DEOXYCYTIDINE FOR REVERSAL OF METHYLATION-ASSOCIATED MIRNA SILENCING. TUMOR SUPPRESSOR PROPERTIES OF MIR-34B WERE DEMONSTRATED BY OVER-EXPRESSION OF PRECURSOR MIR-34B IN MEC-1 CELLS. RESULTS: MIR-34B/C PROMOTER WAS UNMETHYLATED IN NORMAL CONTROLS, BUT COMPLETELY METHYLATED IN 4 CLL CELL LINES. MIR-34B/C EXPRESSION WAS INVERSELY CORRELATED WITH MIR-34B/C METHYLATION. DIFFERENT MSP STATUSES OF MIR-34B/C, INCLUDING COMPLETE METHYLATION AND COMPLETE UNMETHYLATION, WERE VERIFIED BY QUANTITATIVE BISULFITE PYROSEQUENCING. 5-AZA-2'-DEOXYCYTIDINE TREATMENT RESULTED IN PROMOTER DEMETHYLATION AND MIR-34B RE-EXPRESSION IN MEC1 CELLS. MOREOVER, OVER-EXPRESSION OF MIR-34B RESULTED IN INHIBITION OF CELLULAR PROLIFERATION AND INCREASED CELL DEATH. IN PRIMARY CLL SAMPLES, MIR-34A, MIR-34B/C AND DAPK1 METHYLATION WAS DETECTED IN 2.6%, 17.9% AND 34.6% OF PATIENTS AT DIAGNOSIS RESPECTIVELY. FURTHERMORE, 39.7%, 3.8% AND 2.6% PATIENTS HAD METHYLATION OF ONE, TWO OR ALL THREE GENES RESPECTIVELY. OVERALL, 46.2% PATIENTS HAD METHYLATION OF AT LEAST ONE OF THESE THREE GENES. BESIDES, MIR-34B/C METHYLATION WAS ASSOCIATED WITH METHYLATION OF MIR-34A (P = 0.03) AND MIR-203 (P = 0.012) IN CLL. CONCLUSIONS: TAKEN TOGETHER, MIR-34B/C IS A TUMOR SUPPRESSOR MIRNA FREQUENTLY METHYLATED, AND HENCE SILENCED IN CLL. TOGETHER WITH DAPK1 METHYLATION, MIR-34B/C METHYLATION IS IMPLICATED IN THE DISRUPTION OF THE TP53-CENTERED TUMOR SUPPRESSOR NETWORK. MOREOVER, THE ASSOCIATION OF MIRNA METHYLATION WARRANTS FURTHER STUDY. 2014 20 672 29 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