1 6820 161 [GASTRIC CARCINOMA AND CHRONIC GASTRITIS: EPIGENETIC REGULATION OF CDH1 (E-CADHERIN), CDKN2A (P16INK4A), PTGS2 (COX-2) AND EGFR GENES THROUGH METHYLATION]. THE GENETIC AND EPIGENETIC ALTERATIONS ARE BEING STUDIED AS ONE OF THE CAUSES OF GASTRIC CANCER (GC) PROGRESSION AND DEVELOPMENT. DNA METHYLATION IS AN EPIGENETIC ALTERATION WHICH LEADS TO SUPPRESSOR GENE SILENCING AND PROTO-ONCOGENE ACTIVATION, PLAYING AN IMPORTANT ROLE IN CARCINOGENESIS. THE HISTOLOGICAL TYPES OF GASTRIC CARCINOMA HAVE DIFFERENT GENETIC PATHS AND THE KNOWLEDGE OF THE MOLECULAR BASES OF TUMORAL PROGRESSION LEADS TO DIAGNOSTIC ACCURACY AND ATTEMPTED THERAPY. CDH1 (E-CADHERIN) AND CDKN2A (P16(INK4A)) GENES ARE THOUGHT TO BE TUMORAL SUPPRESSOR GENES AND PTGS2 (COX-2) AND GENES ARE INVOLVED IN TUMOUR REGULATION AND GROWTH. IN ONE HAND, GENE SILENCING AS AN EPIGENETIC PHENOMENON, AND IN THE OTHER HAND, GENE EXPRESSION ENHANCEMENT DUE TO POSSIBLE DEMETHYLATION, SIMULTANEOUSLY, CAN FACILITATE CARCINOGENESIS AND TUMORAL PROGRESSION. OUR AIM WAS TO RELATE CDH1, P16(INK4A), COX-2 AND EGFR GENES DNA METHYLATION WITH THE SEVERAL HISTOLOGICAL TYPES OF GASTRIC CARCINOMA AND CHRONIC GASTRITIS. WE STUDIED 55 FORMALIN FIXED PARAFFIN EMBEDDED GASTRIC BIOPSIES: 35 WERE GC SPECIMENS (12 DIFFUSE TYPE, 15 INTESTINAL TYPE AND 8 INDETERMINATE TYPE, ACCORDING TO LAUREN'S CLASSIFICATION) AND 20 SAMPLES HAD CHRONIC GASTRITIS (CG). THE DNA WAS TREATED WITH SODIUM BISULFITE AFTER EXTRACTION AND THEN PERFORMED METHYLATION SPECIFIC PCR (MSP). STATISTICAL ANALYSIS WAS BASED ON CHI-SQUARE TEST AND EXACT FISHER'S TEST. CPG ISLAND METHYLATION WAS DETECTED IN 94% OF THE GC SAMPLES FOR CDH1, 91% FOR COX-2, 80% FOR P16(INK4A) AND NO METHYLATION WAS DETECTED IN EGFR GENE (0%). IN CG, CPG ISLAND METHYLATION WAS FOUND IN 100% FOR CDH1 AND COX-2 GENES, 90% FOR P16(INK4A) AND 20% FOR EGFR. THESE RESULTS REVEAL SIGNIFICANT DIFFERENCES IN EGFR GENE METHYLATION DISTINGUISHING GC FROM CG (P < 0, 01), SUGGESTING THAT GENE DEMETHYLATION LEADS TO MALIGNANT TRANSFORMATION AND FAVOURS THE USE OF TYROSINE-KINASE INHIBITORS IN ITS TREATMENT. GENES COX2 E P16INK4A LOWER METHYLATION IN INTESTINAL AND DIFFUSE TYPES OF GC, FAVOURS THEIR DIFFERENT ROLE IN RESPECTIVE HISTOGENESIS.	2010	
                                                                                               
2 2071  42 EPIGENETIC CONTROL OF THE E-CADHERIN GENE (CDH1) BY CPG METHYLATION IN COLECTOMY SAMPLES OF PATIENTS WITH ULCERATIVE COLITIS. E-CADHERIN BELONGS TO THE CADHERIN FAMILY OF CALCIUM-DEPENDENT CELL-ADHESION MOLECULES. THE CADHERINS PLAY AN ESSENTIAL ROLE IN BIOLOGICAL PROCESSES SUCH AS ORDERING OF CELL SORTING, MIGRATION, AND DIFFERENTIATION, AND THEIR MALFUNCTIONING IS CONNECTED WITH NEOPLASIA. NEOPLASTIC PROGRESSION IN PATIENTS WITH CHRONIC ULCERATIVE COLITIS IS CHARACTERIZED BY THE DEVELOPMENT OF EPITHELIAL DYSPLASIA. TRANSCRIPTIONAL SILENCING OF TUMOR-SUPPRESSOR GENES BY PROMOTER METHYLATION HAS BEEN OBSERVED IN DIFFERENT TYPES OF HUMAN CANCERS AND DYSPLASIA. TO EXPLORE THE MODE OF E-CADHERIN REGULATION, 156 BIOPSY SAMPLES FROM 26 PATIENTS WITH LONG-STANDING ULCERATIVE COLITIS WERE SCREENED. TO DETECT THE METHYLATION STATUS OF OUR SAMPLES, A METHYLATION-SPECIFIC PCR WAS APPLIED. METHYLATION OF THE E-CADHERIN (CDH1) PROMOTER WAS DETECTED IN 93% OF THE PATIENTS WITH DYSPLASTIC BIOPSY SAMPLES, IN CONTRAST TO ONLY 6% OF THE PATIENTS WITHOUT DYSPLASIA (P < 0.001). WE ALSO EXAMINED THE LEVEL OF SYNTHESIS OF E-CADHERIN PROTEIN BY IMMUNOHISTOCHEMICAL STAINING IN DIFFERENT PARAFFIN-EMBEDDED SAMPLES OF DYSPLASTIC AND NON-DYSPLASTIC ORIGIN IN A SUBSET OF OUR PATIENTS. SAMPLES WITH DYSPLASIA DISPLAYED REDUCED LEVELS, WHEREAS SAMPLES WITHOUT DYSPLASIA REVEALED NORMAL E-CADHERIN PROTEIN SYNTHESIS. THESE RESULTS SHOW THAT THE E-CADHERIN PROMOTER IS SUBJECTED TO EPIGENETIC CONTROL IN COLORECTAL ULCERATION. OBVIOUSLY, THIS EVENT MAY PLAY AN IMPORTANT ROLE IN THE PROGRESSION FROM CHRONIC INFLAMMATION TO COLORECTAL CANCER. FOR THIS REASON, METHYLATION OF THE CDH1 PROMOTER IS AN ATTRACTIVE NEW BIOMARKER FOR DETECTING ULCERATIVE COLITIS PATIENTS WITH A HIGH RISK FOR DEVELOPING COLORECTAL CANCERS.	2002	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        
3 4905  38 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	
                                                                                                                                                                                                                                                                                                                                                                                            
4 3444  33 HYPERMETHYLATION OF E-CADHERIN IN LEUKEMIA. E-CADHERIN GENE IS OFTEN TERMED A "METASTASIS SUPPRESSOR" GENE BECAUSE THE E-CADHERIN PROTEIN CAN SUPPRESS TUMOR CELL INVASION AND METASTASIS. INACTIVATION OF THE E-CADHERIN GENE OCCURS IN UNDIFFERENTIATED SOLID TUMORS BY BOTH GENETIC AND EPIGENETIC MECHANISMS; HOWEVER, THE ROLE OF E-CADHERIN IN HEMATOLOGIC MALIGNANCIES IS ONLY NOW BEING RECOGNIZED. E-CADHERIN EXPRESSION IS ESSENTIAL FOR ERYTHROBLAST AND NORMOBLAST MATURATION, YET EXPRESSION IS REDUCED OR ABSENT IN LEUKEMIC BLAST CELLS. THIS STUDY EXAMINED THE MESSENGER RNA (MRNA) AND PROTEIN EXPRESSION OF THE E-CADHERIN GENE IN BONE MARROW AND BLOOD SAMPLES FROM NORMAL DONORS AND PATIENTS WITH LEUKEMIA. WE FOUND THAT ALL NORMAL DONOR SAMPLES EXPRESSED E-CADHERIN MRNA, WHEREAS BOTH SAMPLES OF ACUTE MYELOGENOUS LEUKEMIA AND CHRONIC LYMPHOCYTIC LEUKEMIA HAD A SIGNIFICANT REDUCTION OR ABSENCE OF EXPRESSION. HOWEVER, NORMAL BLAST COUNTERPARTS EXPRESSED ONLY A LOW LEVEL OF E-CADHERIN SURFACE PROTEIN. SODIUM BISULPHITE GENOMIC SEQUENCING WAS USED TO FULLY CHARACTERIZE THE METHYLATION PATTERNS OF THE CPG ISLAND ASSOCIATED WITH THE E-CADHERIN GENE PROMOTER IN THOSE SAMPLES WITH MATCHED DNA. ALL OF THE NORMAL CONTROL SAMPLES WERE ESSENTIALLY UNMETHYLATED; HOWEVER, 14 OF 18 (78%) OF THE LEUKEMIA SAMPLES HAD ABNORMAL HYPERMETHYLATION OF THE E-CADHERIN CPG ISLAND. IN FACT BOTH ALLELES OF THE E-CADHERIN GENE WERE OFTEN HYPERMETHYLATED. WE CONCLUDE THE E-CADHERIN GENE IS A COMMON TARGET FOR HYPERMETHYLATION IN HEMATOLOGIC MALIGNANCIES.	2000	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  
5 2019  40 EPIGENETIC CHANGE IN E-CADHERIN AND COX-2 TO PREDICT CHRONIC PERIODONTITIS. BACKGROUND: DNA METHYLATION OF CERTAIN GENES FREQUENTLY OCCURS IN NEOPLASTIC CELLS. ALTHOUGH THE CAUSE REMAINS UNKNOWN, MANY GENES HAVE BEEN IDENTIFIED WITH SUCH ATYPICAL METHYLATION IN NEOPLASTIC CELLS. THE HYPERMETHYLATION OF E-CADHERIN AND CYCLOOXYGENASE 2 (COX-2) IN CHRONIC INFLAMMATION SUCH AS CHRONIC PERIODONTITIS MAY DEMONSTRATE MILD LESION/MUTATION EPIGENETIC LEVEL. THIS STUDY COMPARES THE HYPERMETHYLATION STATUS OF E-CADHERIN AND COX-2 GENES WHICH ARE OFTEN FOUND IN BREAST CANCER PATIENTS WITH THAT IN CHRONIC PERIODONTITIS. METHODS: TOTAL DNA WAS EXTRACTED FROM THE BLOOD SAMPLES OF 108 SYSTEMICALLY HEALTHY NON-PERIODONTITIS SUBJECTS, AND THE GINGIVAL TISSUES AND BLOOD SAMPLES OF 110 CHRONIC PERIODONTITIS PATIENT AS WELL AS NEOPLASTIC TISSUES OF 106 BREAST CANCER PATIENTS. METHYLATION-SPECIFIC PCR FOR E-CADHERIN AND COX-2 WAS PERFORMED ON THESE SAMPLES AND THE PCR PRODUCTS WERE ANALYZED ON 2% AGAROSE GEL. RESULTS: HYPERMETHYLATION OF E-CADHERIN AND COX-2 WAS OBSERVED IN 38% AND 35% OF THE BREAST CANCER SAMPLES, RESPECTIVELY. IN CHRONIC PERIODONTITIS PATIENTS THE DETECTION RATE WAS 25% AND 19% RESPECTIVELY, AND NONE WAS FOUND IN THE SYSTEMICALLY HEALTHY NON-PERIODONTITIS CONTROL SUBJECTS. THE HYPERMETHYLATION STATUS WAS SHOWN TO BE CORRELATED AMONG THE THREE GROUPS WITH STATISTICAL SIGNIFICANCE (P < 0.0001). THE METHYLATION OF CPG ISLANDS IN E-CADHERIN AND COX-2 GENES IN PERIODONTITIS PATIENTS OCCURS MORE FREQUENTLY IN PERIODONTITIS PATIENTS THAN IN THE CONTROL SUBJECTS, BUT OCCURS LESS FREQUENTLY THAN IN THE BREAST CANCER PATIENTS. CONCLUSIONS: THIS SET OF DATA SHOWS THAT THE EPIGENETIC CHANGE IN E-CADHERIN AND CYCLOOXYGENASE-2 IS ASSOCIATED WITH CHRONIC PERIODONTITIS. THE EPIGENETIC CHANGES PRESENTED IN CHRONIC INFLAMMATION PATIENTS MIGHT DEMONSTRATE AN IRREVERSIBLE DESTRUCTION IN THE TISSUES OR ORGANS SIMILAR TO THE EFFECTS OF CANCER. CHRONIC PERIODONTITIS TO SOME EXTENT MIGHT BE ASSOCIATED WITH DNA HYPERMETHYLATION WHICH IS RELATED TO CANCER RISK FACTORS.	2010	
                                                                                                                                                                                                                                                          
6 3897  41 LARGE-SCALE ANALYSIS OF THE GENETIC AND EPIGENETIC ALTERATIONS IN HEPATOCELLULAR CARCINOMA FROM SOUTHEAST CHINA. OUR KNOWLEDGE ABOUT MOLECULAR ALTERATIONS DURING HEPATOCARCINOGENESIS IS STILL FRAGMENTARY, DUE TO LACK OF COMPREHENSIVE GENETIC AND EPIGENETIC ANALYSES IN THE SAME SET OF HEPATOCELLULAR CARCINOMAS (HCCS). IN THIS STUDY, WE CONDUCTED A LARGE-SCALE ANALYSIS, INCLUDING MUTATION SCREENING IN 50 GENES AND METHYLATION ASSAYS IN THREE GENES IN 54 PAIRS OF HCCS AND THEIR NEIGHBORING NON-CANCEROUS TISSUES. ALL SAMPLES WERE COLLECTED FROM THE RESIDENTS IN SOUTHEAST CHINA. WE FOUND HBV INFECTION AND CHRONIC HEPATITIS/CIRRHOSIS IN 83.3% AND 98.1% OF THE CASES, RESPECTIVELY. MUTATIONS WERE IDENTIFIED IN 18 OUT OF 54 (33.3%) SAMPLES, WITH P53 ALTERATIONS IN 14 CASES AND BETA-CATENIN MUTATIONS IN FOUR TUMORS. NO MUTATIONS WERE IDENTIFIED IN THE NEIGHBORING TISSUES. INTERESTINGLY, 9 OUT OF 14 (64.3%) TUMORS CARRYING P53 MUTATIONS DISPLAYED SUBSTITUTION OF SERINE BY ARGININE AT CODON 249, A CHARACTERISTIC CHANGE BELIEVED TO BE INDUCED BY AFLATOXIN-B1. FURTHERMORE, P53 MUTATION WAS SIGNIFICANTLY ASSOCIATED WITH SHORTER RECURRENCE-FREE SURVIVAL (P=0.004). THE RESULTS ALSO REVEALED ABERRANT METHYLATION IN TWO OR MORE GENES IN AS HIGH AS 90% OF TUMORS AND 40% OF ADJACENT TISSUES. THE FREQUENCY OF RASSF1A HYPERMETHYLATION WAS MUCH HIGHER THAN THAT OF P16INK4A AND HAI2 IN BOTH HCC AND NEIGHBORING TISSUES, INDICATING THAT DEREGULATION OF RASSF1A MAY PRECEDE THE OTHER TWO GENES. THESE DATA SUGGEST THAT ABERRANT METHYLATION OCCURS BEFORE MUTATION AND IS AN EARLY EVENT IN THE DEVELOPMENT OF THIS SET OF HCC. OUR FINDINGS HIGHLIGHT P53 AS A PROGNOSTIC FACTOR OF HCC AND RASSF1A AS A POTENTIAL TARGET IN PREVENTING MALIGNANT TRANSFORMATION OF HEPATOCYTES.	2008	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
7 3646  34 INCREASED PROTEIN EXPRESSION OF DNA METHYLTRANSFERASE (DNMT) 1 IS SIGNIFICANTLY CORRELATED WITH THE MALIGNANT POTENTIAL AND POOR PROGNOSIS OF HUMAN HEPATOCELLULAR CARCINOMAS. ALTERATION OF DNA METHYLATION IS ONE OF THE MOST CONSISTENT EPIGENETIC CHANGES IN HUMAN CANCERS. DNA METHYLTRANSFERASE (DNMT) 1 IS A MAJOR ENZYME INVOLVED IN ESTABLISHING GENOMIC METHYLATION PATTERNS. MOST OF THE STUDIES CONCERNING DNMT1 EXPRESSION IN HUMAN CANCERS HAVE BEEN PERFORMED ONLY AT THE MRNA LEVEL. TO DIRECTLY EXAMINE DNMT1 PROTEIN EXPRESSION LEVELS DURING HUMAN HEPATOCARCINOGENESIS, 16 HISTOLOGICALLY NORMAL LIVER TISSUES, 51 NONCANCEROUS LIVER TISSUES EXHIBITING CHRONIC HEPATITIS OR CIRRHOSIS, WHICH ARE CONSIDERED TO BE PRECANCEROUS CONDITIONS, AND 53 HEPATOCELLULAR CARCINOMAS (HCCS) WERE SUBJECTED TO IMMUNOHISTOCHEMIC EXAMINATION. IF MORE THAN 20% OF THE CELLS EXHIBITED NUCLEAR DNMT1 STAINING, THE TISSUE SAMPLE WAS CONSIDERED TO BE DNMT1-POSITIVE. DNMT1 IMMUNOREACTIVITY WAS OBSERVED IN 23 (43%) OF THE HCCS, BUT IN NONE (0%) OF THE HISTOLOGICALLY NORMAL LIVER OR NONCANCEROUS LIVER TISSUES EXHIBITING CHRONIC HEPATITIS OR CIRRHOSIS. THE INCIDENCE OF INCREASED DNMT1 PROTEIN EXPRESSION IN HCCS CORRELATED SIGNIFICANTLY WITH POOR TUMOR DIFFERENTIATION (P = 0.0006) AND PORTAL VEIN INVOLVEMENT (P = 0.0002). MOREOVER, THE RECURRENCE-FREE (P = 0.0001) AND OVERALL (P < 0.0001) SURVIVAL RATES OF PATIENTS WITH HCCS EXHIBITING INCREASED DNMT1 PROTEIN EXPRESSION WERE SIGNIFICANTLY LOWER THAN THOSE OF PATIENTS WITH HCCS THAT DID NOT EXHIBIT INCREASED EXPRESSION. INCREASED DNMT1 PROTEIN EXPRESSION MAY PLAY A CRITICAL ROLE IN THE MALIGNANT PROGRESSION OF HCCS AND BE A BIOLOGIC PREDICTOR OF BOTH HCC RECURRENCE AND A POOR PROGNOSIS IN HCC PATIENTS.	2003	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          
8 5276  40 PROMOTER METHYLATION OF TUMOR-RELATED GENES IN GASTRIC CARCINOGENESIS. ABERRANT PROMOTER METHYLATION AND SUBSEQUENT SILENCING OF CANCER-RELATED GENES HAS BEEN RECOGNIZED AS AN IMPORTANT PATHWAY INVOLVED IN GASTRIC CARCINOGENESIS. IN FACT, SEVERAL FACTORS ARE BELIEVED TO CONTRIBUTE TO ITS INDUCTION IN GASTRIC EPITHELIA, INCLUDING AGING, DIET, CHRONIC INFLAMMATION AND INFECTION OF HELICOBACTER PYLORI (H. PYLORI) AND EPSTEIN-BARR VIRUS (EBV). HOWEVER, THE UNDERLING MECHANISMS ARE NOT COMPLETELY IDENTIFIED, DESPITE THE BELIEF THAT INCREASED EXPRESSION OR ACTIVITY OF DNA METHYLTRANSFERASES (DNMTS), OR DECREASED DEMETHYLATION ACTIVITY MAY CONTRIBUTE TO THE EXCESSIVE METHYLATION. A GREAT NUMBER OF GENES WITH PROMOTER METHYLATION HAVE BEEN OBSERVED IN GASTRIC CANCER (GC), AMONG WHICH P16INK4A (P16), MUT L HOMOLOGUE 1 (MLH1), EPITHELIAL-CADHERIN (E-CADHERIN), RUNT-RELATED TRANSCRIPTION FACTOR 3 (RUNX3), ADENOMATOUS POLYPOSIS COLI (APC), O(6)-METHYLGUANINE-DNA METHYLTRANSFERASE (MGMT), RAS ASSOCIATION DOMAIN FAMILY 1A (RASSF1A) AND DEATH-ASSOCIATED PROTEIN KINASE (DAPK) HAVE BEEN EXTENSIVELY STUDIED. UNLIKE THE DISTINCT METHYLATION CHARACTERIZATION IN SINGLE GENES, METHYLATION ANALYSIS OF MULTIPLE GENES MAY PROVIDE MORE INFORMATION IN RISK PREDICTION, EARLY DETECTION, PROGNOSIS ASSESSMENT AND CHEMOTHERAPY CHOICE FOR GC. SPECIFICALLY, PARTICULAR MONITORING AND SCREENING SHOULD BE PERFORMED ON THOSE OVER 45 YEARS OLD, WITH PRECANCEROUS GASTRIC DISEASE OR INFECTION OF H. PYLORI OR EBV. AS AN ALTERNATIVE TO TUMOR TISSUES, METHYLATION DETECTION IN PATIENT SERA OR GASTRIC WASHES MAY ALSO BE USED IN RISK PREDICTION AND EARLY DETECTION. HOWEVER, WHAT STILL POSES A GREAT CHALLENGE AS WELL AS A PUZZLE IS THE DETERMINATION OF THE VERY GENES THAT SHOULD BE USED IN METHYLATION ANALYSIS. BECAUSE EPIGENETIC ALTERATIONS ARE NORMALLY REVERSIBLE, DRUGS OR CHEMICAL COMPOUNDS WITH DEMETHYLATING ACTIVITY, SUCH AS 5-AZA-2'-DEOXYCYTIDINE (5-AZA-DC) COULD BE USED IN THE TREATMENT OF PATIENTS WITH MULTIPLE GENE METHYLATION. IN VIEW OF THE ADVERSE EFFECTS OF 5-AZA-DC, DNMT-TARGETED STRATEGY HAS BEEN PROPOSED AND MAY PROVE TO BE MORE EFFECTIVE THAN DEMETHYLATING AGENTS.	2012	
                                                                                                                                                           
9  507  38 ASSOCIATION OF INCREASED DNA METHYLTRANSFERASE EXPRESSION WITH CARCINOGENESIS AND POOR PROGNOSIS IN PANCREATIC DUCTAL ADENOCARCINOMA. INTRODUCTION: EPIGENETIC MODIFICATIONS PLAY AN IMPORTANT ROLE IN MULTISTAGE CARCINOGENESIS. THE ROLE OF THE THREE FUNCTIONAL DNA METHYLTRANSFERASES (DNMTS) IN PANCREATIC CARCINOGENESIS HAS NOT BEEN FULLY UNDERSTOOD. THE MAIN GOAL OF THIS STUDY WAS TO EXAMINE DNMT EXPRESSION IN DIFFERENT STAGES OF PANCREATIC DUCTAL ADENOCARCINOMA (PDAC), AND EVALUATE THEIR PROGNOSTIC SIGNIFICANCE IN PDAC. MATERIALS AND METHODS: A LARGE NUMBER OF PREMALIGNANT AND MALIGNANT PANCREATIC LESIONS WERE OBTAINED BY MANUAL MICRODISSECTION. QUANTITATIVE REAL-TIME RT-PCR WAS USED TO DETECT DNMTS MRNA EXPRESSION. NONPARAMETRIC TEST, LOGRANK TEST AND COX REGRESSION ANALYSIS WERE USED TO EVALUATE THE CLINICAL SIGNIFICANCE OF DNMT EXPRESSION. RESULTS: THE MRNA EXPRESSION OF THE THREE DNMTS INCREASED WITH THE DEVELOPMENT OF PANCREATIC CANCER FROM NORMAL DUCT TO PANCREATIC INTRADUCTAL NEOPLASIA AND FURTHER TO PDAC, AND WERE STATISTICALLY CORRELATED WITH EACH OTHER. EXPRESSION OF THE THREE DNMTS WAS STATISTICALLY CORRELATED WITH TNM STAGING AND HISTORY OF CHRONIC PANCREATITIS. DNMT3A AND DNMT3B, BUT NOT DNMT1 EXPRESSION, WAS STATISTICALLY CORRELATED WITH TUMOUR SIZE. PATIENTS WITH HIGHER LEVELS OF DNMT1, DNMT3A AND/OR DNMT3B EXPRESSION HAD AN OVERALL LOWER SURVIVAL THAN THOSE WITH LOWER LEVELS OF EXPRESSION. UNIVARIATE ANALYSIS SHOWED THAT HIGH EXPRESSION LEVELS OF DNMTS, ALCOHOL CONSUMPTION, TUMOUR DIFFERENTIATION AND TNM STAGING WERE STATISTICALLY SIGNIFICANT RISK FACTORS. MULTIVARIATE ANALYSIS SHOWED THAT HIGH LEVEL OF DNMT3B EXPRESSION AND TUMOUR DIFFERENTIATION WERE STATISTICALLY SIGNIFICANT INDEPENDENT POOR PROGNOSTIC FACTORS. CONCLUSIONS: THESE RESULTS SUGGESTED THAT PANCREATIC CARCINOGENESIS INVOLVES AN INCREASED MRNA EXPRESSION OF THREE DNMTS, AND THEY MAY BECOME VALUABLE DIAGNOSTIC AND PROGNOSTIC MARKERS AS WELL AS POTENTIAL THERAPEUTIC TARGETS FOR PANCREATIC CANCER.	2012	
                                                                                                                                                                                                                                                                                                                               
10   59  40 A GENOME-WIDE SCREEN IDENTIFIES FREQUENTLY METHYLATED GENES IN HAEMATOLOGICAL AND EPITHELIAL CANCERS. BACKGROUND: GENETIC AS WELL AS EPIGENETIC ALTERATIONS ARE A HALLMARK OF BOTH EPITHELIAL AND HAEMATOLOGICAL MALIGNANCIES. HIGH THROUGHPUT SCREENS ARE REQUIRED TO IDENTIFY EPIGENETIC MARKERS THAT CAN BE USEFUL FOR DIAGNOSTIC AND PROGNOSTIC PURPOSES ACROSS MALIGNANCIES. RESULTS: HERE WE REPORT FOR THE FIRST TIME THE USE OF THE MIRA ASSAY (METHYLATED CPG ISLAND RECOVERY ASSAY) IN COMBINATION WITH GENOME-WIDE CPG ISLAND ARRAYS TO IDENTIFY EPIGENETIC MOLECULAR MARKERS IN CHILDHOOD ACUTE LYMPHOBLASTIC LEUKEMIA (ALL) ON A GENOME-WIDE SCALE. WE IDENTIFIED 30 GENES DEMONSTRATING METHYLATION FREQUENCIES OF > OR =25% IN CHILDHOOD ALL, NINE GENES SHOWED SIGNIFICANTLY DIFFERENT METHYLATION FREQUENCIES IN B VS T-ALL. FOR MAJORITY OF THE GENES EXPRESSION COULD BE RESTORED IN METHYLATED LEUKEMIA LINES AFTER TREATMENT WITH 5-AZADC. FORTY-FOUR PERCENT OF THE GENES REPRESENT TARGETS OF THE POLYCOMB COMPLEX. IN CHRONIC MYELOID LEUKEMIA (CML) TWO OF THE GENES, (TFAP2A AND EBF2), DEMONSTRATED INCREASED METHYLATION IN BLAST CRISIS COMPARED TO CHRONIC PHASE (P < 0.05). FURTHERMORE HYPERMETHYLATION OF AN AUTOPHAGY RELATED GENE ATG16L2 WAS ASSOCIATED WITH POORER PROGNOSIS IN TERMS OF MOLECULAR RESPONSE TO IMATINIB TREATMENT. LASTLY WE DEMONSTRATED THAT TEN OF THESE GENES WERE ALSO FREQUENTLY METHYLATED IN COMMON EPITHELIAL CANCERS. CONCLUSION: IN SUMMARY WE HAVE IDENTIFIED A LARGE NUMBER OF GENES SHOWING FREQUENT METHYLATION IN CHILDHOOD ALL, METHYLATION STATUS OF TWO OF THESE GENES IS ASSOCIATED WITH ADVANCED DISEASE IN CML AND METHYLATION STATUS OF ANOTHER GENE IS ASSOCIATED WITH PROGNOSIS. IN ADDITION A SUBSET OF THESE GENES MAY ACT AS EPIGENETIC MARKERS ACROSS HEMATOLOGICAL MALIGNANCIES AS WELL AS COMMON EPITHELIAL CANCERS.	2010	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             
11 1805  28 EFFECT OF SMOKING ON THE DNA METHYLATION PATTERN OF THE SOCS1 PROMOTER IN EPITHELIAL CELLS FROM THE SALIVA OF PATIENTS WITH CHRONIC PERIODONTITIS. BACKGROUND: THE AIM OF THE PRESENT STUDY WAS TO EVALUATE THE METHYLATION PATTERN IN THE SUPPRESSOR OF CYTOKINE SIGNALING 1 (SOCS1) GENE IN SMOKERS AND NON-SMOKERS WITH CHRONIC PERIODONTITIS (CP). METHODS: METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION (PCR) WAS PERFORMED TO DETERMINE THE METHYLATION STATUS OF THE SOCS1 PROMOTER IN 45 SALIVA SAMPLES FROM SMOKERS AND NON-SMOKERS WITH CP. RESULTS: CELLS FROM THE SALIVA OF CP PATIENTS WHO SMOKED WERE 7.08 TIMES MORE LIKELY TO HAVE A METHYLATED SOCS1 PROMOTER THAN CELLS FROM THE SALIVA OF NON-SMOKING PATIENTS. CONCLUSIONS: SOCS1 GENE PROMOTER METHYLATION, WITH ITS POTENTIAL EFFECTS ON THE EXPRESSION OF THIS GENE, SEEMS TO BE A CONSEQUENCE OF EXPOSURE TO TOBACCO AND NOT TO PERIODONTAL DISEASE. FURTHER STUDIES ARE NEEDED TO ELUCIDATE THE RELATIONSHIP BETWEEN THE EPIGENETIC CONTROL OF IMMUNE RESPONSE GENE EXPRESSION, EXPOSURE TO ENVIRONMENTAL FACTORS, AND THE DEVELOPMENT, PROGRESSION, AND PROGNOSIS OF CP.	2019	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
12 2135  50 EPIGENETIC INACTIVATION OF TUMOR SUPPRESSOR GENES IN SERUM OF PATIENTS WITH CUTANEOUS MELANOMA. SMALL AMOUNTS OF CELL-FREE DNA CIRCULATE IN BOTH HEALTHY AND DISEASED HUMAN BLOOD, WHILE INCREASED CONCENTRATIONS OF DNA ARE PRESENT IN THE SERUM OF CANCER PATIENTS. TUMOR-SPECIFIC MUTATIONS OR EPIGENETIC MODIFICATIONS HAVE PREDOMINANTLY BEEN DETECTED IN TISSUE SPECIMENS. THE PURPOSE OF THIS STUDY WAS TO INVESTIGATE METHYLATION OF FIVE DIFFERENT GENES INVOLVED IN TUMOR SUPPRESSION AND DNA REPAIR (SUPPRESSORS OF CYTOKINE SIGNALING 1 AND 2 (SOCS1, SOCS2)), RAS-ASSOCIATION DOMAIN FAMILY PROTEIN 1A (RASSF1A), D-TYPE P16(INK4A) CYCLIN-DEPENDENT KINASE INHIBITOR (CDKN), AND O6-METHYLGUANINE DNA-METHYLTRANSFERASE (MGMT)) IN THE SERUM OF 100 PATIENTS USING METHYLATION-SPECIFIC PCR. IN ALL, 41 MELANOMA PATIENTS (STAGE I = 18; STAGE II = 10; STAGE III/IV = 13), 13 HEALTHY CONTROLS WITHOUT NEVI, AND 10 INDIVIDUALS WITH MORE THAN 15 NEVI OF >5 MM IN SIZE WERE INVESTIGATED. FOR COMPARISON, SERA FROM PATIENTS WITH OTHER SKIN TUMORS (NINE BASAL CELL CANCERS, FIVE KAPOSI'S SARCOMA), DIFFERENT METASTASIZED CANCERS (FIVE BREAST CANCERS, FIVE COLON CANCERS), AND SEVERAL CHRONIC INFLAMMATORY DISEASES (N = 12) WERE ALSO ANALYZED. IN ADDITION, WE EXAMINED IF METHYLATION WAS INVOLVED IN SILENCING TRANSCRIPTION OF THESE GENES IN 12 MELANOMA SPECIMENS. SOCS1, SOCS2, RASSF1A, CDKN2A, AND MGMT WERE METHYLATED IN 75, 43, 64, 75, AND 64% OF MELANOMA SAMPLES, RESPECTIVELY. OF THE 41 MELANOMA PATIENTS, 83% HAD ONE HYPERMETHYLATED GENE, WHILE 66, 51, AND 41% HAD TWO, THREE, OR FOUR HYPERMETHYLATED GENES, RESPECTIVELY. ALSO, 20% OF THESE PATIENTS SHOWED HYPERMETHYLATION FOR ALL GENES, WHILE ONLY 17% SHOWED NO METHYLATION. IMPORTANTLY, THE METHYLATION PROFILE OF THE SELECTED GENES FROM MELANOMA PATIENTS WAS DISTINCT FROM THE OTHER ANALYZED TUMORS. TRANSCRIPTION OF SOCS1, SOCS2, CDKN2A, AND RASSF1A GENES WAS SIGNIFICANTLY REDUCED IN FRESH MELANOMA SAMPLES, WHILE MGMT SHOWED A 12-FOLD UPREGULATION AT THE MESSENGER RIBONUCLEIC ACID LEVEL (P < 0.001). OUR FINDINGS SUGGEST THAT EPIGENETIC SILENCING OF THE STUDIED TUMOR SUPPRESSOR GENES IS A COMMON AND PROBABLY IMPORTANT MECHANISM FOR MELANOMA FORMATION. THIS CONVENIENT METHOD USING A SIMPLE BLOOD SAMPLE MAY CONTRIBUTE TO CLASSIFICATION OF MELANOMA AND AWAITS CLINICAL VALIDATION.	2006	

13 6692  36 VARIABLE DNA METHYLATION PATTERNS ASSOCIATED WITH PROGRESSION OF DISEASE IN HEPATOCELLULAR CARCINOMAS. HEPATOCELLULAR CARCINOMA (HCC) MOST COMMONLY ARISES FROM CHRONIC INFLAMMATION DUE TO VIRAL INFECTION, AS A RESULT OF GENETIC AND EPIGENETIC ABNORMALITIES. A GLOBAL PICTURE OF EPIGENETIC CHANGES IN HCC IS LACKING. WE USED METHYLATED CPG ISLAND AMPLIFICATION MICROARRAYS (MCAMS) TO STUDY 6458 CPG ISLANDS IN HCC AND ADJACENT PRENEOPLASTIC TISSUES [CHRONIC HEPATITIS (CH) OR LIVER CIRRHOSIS (LC)] IN COMPARISON WITH NORMAL LIVER TISSUES WHERE NEITHER VIRAL INFECTION NOR HEPATITIS HAS EXISTED. MCAM IDENTIFIED 719 (11%) PROMINENT GENES OF HYPERMETHYLATION IN HCCS. HCCS ARISING FROM LC HAD SIGNIFICANTLY MORE METHYLATION THAN THOSE ARISING FROM CH (1249 GENES OR 19% VERSUS 444 GENES OR 7%, P < 0.05). THERE WERE FOUR PATTERNS OF ABERRANT METHYLATION: TYPE I (4%, E.G. MATRIX METALLOPROTEINASE 14) SHOWS A SUBSTANTIALLY HIGH METHYLATION LEVEL IN ADJACENT TISSUE AND DOES NOT INCREASE FURTHER IN CANCER. TYPE II (55%, E.G. RASSF1A) SHOWS PROGRESSIVELY INCREASING METHYLATION FROM ADJACENT TISSUE TO HCC. TYPE III (4%, E.G. GNA14) SHOWS DECREASED METHYLATION IN ADJACENT TISSUE BUT EITHER SIMILAR OR INCREASED METHYLATION IN HCC. TYPE IV (37%, E.G. CDKN2A) SHOWS LOW LEVELS OF METHYLATION IN NORMAL TISSUE AND ADJACENT TISSUE BUT HIGH LEVELS IN HCC. THESE DNA METHYLATION CHANGES WERE CONFIRMED BY QUANTITATIVE PYROSEQUENCING METHYLATION ANALYSIS IN REPRESENTATIVE 24 GENES AND WERE ANALYZED FOR CORRELATION WITH CLINICOPATHOLOGICAL PARAMETERS IN 38 PATIENTS. INTRIGUINGLY, METHYLATION IN THE TYPE IV GENES IS CHARACTERISTIC OF MODERATELY/POORLY DIFFERENTIATED CANCER. OUR GLOBAL EPIGENOME ANALYSIS REVEALS DISTINCT PATTERNS OF METHYLATION THAT ARE PROBABLY TO REPRESENT DIFFERENT PATHOPHYSIOLOGIC PROCESSES IN HCCS.	2008	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
14 2682  32 EVALUATION OF SERUM LINE-1 HYPOMETHYLATION AS A PROGNOSTIC MARKER FOR HEPATOCELLULAR CARCINOMA. BACKGROUND AND STUDY AIMS: GLOBAL HYPOMETHYLATION IS ONE OF THE MOST CONSISTENT EPIGENETIC CHANGES IN CANCER. DEVELOPMENT OF HEPATOCELLULAR CARCINOMA (HCC) MUST BE UNDERSTOOD AS A MULTISTEP PROCESS WITH ACCUMULATION OF GENETIC AND EPIGENETIC ALTERATIONS. IN THE LAST DECADES, IN ADDITION TO GENETIC ALTERATIONS, EPIGENETIC CHANGES HAVE BEEN RECOGNIZED AS AN IMPORTANT AND ALTERNATIVE MECHANISM IN TUMOURIGENESIS. WE INVESTIGATED THE CLINICAL IMPLICATIONS OF GLOBAL HYPOMETHYLATION IN THE SERA OF PATIENTS WITH HEPATOCELLULAR CARCINOMA (HCC). PATIENTS AND METHODS: PCR WAS USED TO ASSESS THE METHYLATION STATUS OF LONG INTERSPERSED NUCLEAR ELEMENT TYPE 1 (LINE-1) REPETITIVE SEQUENCES IN GENOMIC DNA DERIVED FROM SERA OF 50 PATIENTS WITH HCC, 20 PATIENTS WITH CIRRHOSIS, 20 PATIENTS WITH CHRONIC HEPATITIS C AND 10 HEALTHY SUBJECTS. RESULTS: SERUM GENOME HYPOMETHYLATION WAS SIGNIFICANTLY INCREASED IN PATIENTS WITH HCC (P<0.001). THE LEVELS OF SERUM LINE-1 HYPOMETHYLATION AT INITIAL PRESENTATION CORRELATED SIGNIFICANTLY WITH TUMOUR SIZE, TUMOUR NUMBER AND ALPHA-FOETOPROTEIN LEVEL. MOREOVER HIGH SERUM LINE-1 HYPOMETHYLATION CORRELATES SIGNIFICANTLY WITH POOR SURVIVAL. CONCLUSION: SERUM LINE-1 HYPOMETHYLATION MAY SERVE AS A PROGNOSTIC MARKER FOR PATIENTS WITH HCC.	2011	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
15 5435  31 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	
                                                                                                                                                                                                                                                                                                                                                                                                                
16 1342  34 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	
                                                                                                                                                                                          
17 3588  45 IMPACT OF TP53 GENE PROMOTER METHYLATION ON CHRONIC LYMPHOCYTIC LEUKEMIA PATHOGENESIS AND PROGRESSION. BACKGROUND: CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) IS A MALIGNANT LYMPHOID DISORDER THAT RESULTS FROM THE OVERGROWTH OF MATURE-LOOKING LYMPHOID CELLS IN THE BLOOD AND LYMPHATIC TISSUE. VARIOUS CLINICAL PRESENTATIONS HAVE BEEN ATTRIBUTED TO THE DISEASE AS A RESULT OF THE DIFFERENT UNDERLYING GENETIC AND EPIGENETIC ALTERATIONS. THE CURRENT STUDY HAS BEEN INITIATED TO STUDY THE ROLE OF AN EPIGENETIC ALTERATION AFFECTING THE PROMOTER OF THE TP53GENE ON CLL PATHOGENESIS AND PROGRESSION. METHODS: THE CURRENT STUDY INVOLVED 54 NEWLY DIAGNOSED PATIENTS PRESENTING WITH CLL AS WELL AS 30 NORMAL INDIVIDUALS AS CONTROLS. AFTER OBTAINING VERBAL CONSENT, DATA COLLECTION WAS DONE AND THE BLOOD COLLECTED FROM ALL ENROLLED INDIVIDUALS FOR HEMATOLOGICAL INVESTIGATIONS AS WELL AS FOR MOLECULAR CATEGORIZATION OF TP53 METHYLATION STATUS. METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION (MS-PCR) TECHNIQUE WAS USED TO DEFINE THE METHYLATION STATUS OF THE TP53 GENE PROMOTER THAT ENCOMPASSES DNA EXTRACTION, BISULFITE CONVERSION, CONVENTIONAL PCR AMPLIFICATION, RUNNING ON AGAROSE GEL AND DOCUMENTATION. FINALLY, STATISTICAL ANALYSIS WAS DONE TO ASSESS ANY CORRELATION OF THE TP53 EPIGENETIC ALTERATION TO THE DISEASE ETIOLOGY AND THE PROGRESSION. RESULTS: IN THE CURRENT STUDY, ALL CONTROLS AND 42 OF 54 PATIENTS SHOW UNMETHYLATED TP53 GENE PROMOTER; ON THE OTHER HAND, THE METHYLATED PROMOTER WAS DETECTED AMONG 12 PATIENTS WITH A P-VALUE OF 0.001. TP53 GENE PROMOTER METHYLATION SIGNIFICANTLY LINKED TO REDUCED PLATELET COUNT (P-VALUE OF 0.047) AND ADVANCED STAGE AT PRESENTATION (P-VALUE OF 0.076). NO SIGNIFICANT DIFFERENCES WERE SEEN AMONG BOTH METHYLATED AND UNMETHYLATED TP53 PROMOTERS IN RELATION TO THE AGE OF THE AFFECTED INDIVIDUALS, TOTAL WHITE BLOOD CELL COUNTS AND HEMOGLOBIN LEVEL OF THE AFFECTED INDIVIDUALS. CONCLUSION: THE CURRENT STUDY REVEALED A SIGNIFICANT CORRELATION OF TP53 GENE PROMOTER METHYLATION TO CHRONIC LYMPHOCYTIC LEUKEMIA PATHOGENESIS AND LOWER PLATELET COUNTS.	2019	
                                                                                                                                                                                                                                                  
18 4725  28 NORMAL GASTRIC TISSUE HELICOBACTER PYLORI INFECTION IS ASSOCIATED WITH EPIGENETIC AGE ACCELERATION, INCREASED MITOTIC TICK RATE, TISSUE CELL COMPOSITION, AND NATURAL KILLER CELL METHYLATION ALTERATIONS. BACKGROUND: GASTRIC ADENOCARCINOMAS ARE A LEADING CAUSE OF GLOBAL MORTALITY, ASSOCIATED WITH CHRONIC INFECTION WITH HELICOBACTER PYLORI . THE MECHANISMS BY WHICH INFECTION WITH H. PYLORI CONTRIBUTES TO CARCINOGENESIS ARE NOT WELL UNDERSTOOD. RECENT STUDIES FROM SUBJECTS WITH AND WITHOUT GASTRIC CANCER HAVE IDENTIFIED SIGNIFICANT DNA METHYLATION ALTERATIONS IN NORMAL GASTRIC MUCOSA ASSOCIATED WITH H. PYLORI INFECTION AND GASTRIC CANCER RISK. HERE WE FURTHER INVESTIGATED DNA METHYLATION ALTERATIONS IN NORMAL GASTRIC MUCOSA IN GASTRIC CANCER CASES (N = 42) AND CONTROL SUBJECTS (N = 42) WITH H. PYLORI INFECTION DATA. WE ASSESSED TISSUE CELL TYPE COMPOSITION, DNA METHYLATION ALTERATIONS WITHIN CELL POPULATIONS, EPIGENETIC AGING, AND REPETITIVE ELEMENT METHYLATION. RESULTS: IN NORMAL GASTRIC MUCOSA OF BOTH GASTRIC CANCER CASES AND CONTROL SUBJECTS, WE OBSERVED INCREASED EPIGENETIC AGE ACCELERATION ASSOCIATED WITH H. PYLORI INFECTION. WE ALSO OBSERVED AN INCREASED MITOTIC TICK RATE ASSOCIATED WITH H. PYLORI INFECTION IN BOTH GASTRIC CANCER CASES AND CONTROLS. SIGNIFICANT DIFFERENCES IN IMMUNE CELL POPULATIONS ASSOCIATED WITH H. PYLORI INFECTION IN NORMAL TISSUE FROM CANCER CASES AND CONTROLS WERE IDENTIFIED USING DNA METHYLATION CELL TYPE DECONVOLUTION. WE ALSO FOUND NATURAL KILLER CELL-SPECIFIC METHYLATION ALTERATIONS IN NORMAL MUCOSA FROM GASTRIC CANCER PATIENTS WITH H. PYLORI INFECTION. CONCLUSIONS: OUR FINDINGS FROM NORMAL GASTRIC MUCOSA PROVIDE INSIGHT INTO UNDERLYING CELLULAR COMPOSITION AND EPIGENETIC ASPECTS OF H. PYLORI ASSOCIATED GASTRIC CANCER ETIOLOGY.	2023	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           
19 2771  26 EXTENSIVE PROMOTER DNA HYPERMETHYLATION AND HYPOMETHYLATION IS ASSOCIATED WITH ABERRANT MICRORNA EXPRESSION IN CHRONIC LYMPHOCYTIC LEUKEMIA. DYSREGULATED MICRORNA (MIRNA) EXPRESSION CONTRIBUTES TO THE PATHOGENESIS OF HEMATOPOIETIC MALIGNANCIES, INCLUDING CHRONIC LYMPHOCYTIC LEUKEMIA (CLL). HOWEVER, AN UNDERSTANDING OF THE MECHANISMS THAT CAUSE ABERRANT MIRNA TRANSCRIPTIONAL CONTROL IS LACKING. IN THIS STUDY, WE COMPREHENSIVELY INVESTIGATED THE ROLE AND EXTENT OF MIRNA EPIGENETIC REGULATION IN CLL. GENOME-WIDE PROFILING CONDUCTED ON 24 CLL AND 10 HEALTHY B CELL SAMPLES REVEALED GLOBAL DNA METHYLATION PATTERNS UPSTREAM OF MIRNA SEQUENCES THAT DISTINGUISHED MALIGNANT FROM HEALTHY CELLS AND IDENTIFIED PUTATIVE MIRNA PROMOTERS. INTEGRATION OF DNA METHYLATION AND MIRNA PROMOTER DATA LED TO THE IDENTIFICATION OF 128 RECURRENT MIRNA TARGETS FOR ABERRANT PROMOTER DNA METHYLATION. DNA HYPOMETHYLATION ACCOUNTED FOR MORE THAN 60% OF ALL ABERRANT PROMOTER-ASSOCIATED DNA METHYLATION IN CLL, AND PROMOTER DNA HYPOMETHYLATION WAS RESTRICTED TO WELL-DEFINED REGIONS. INDIVIDUAL HYPER- AND HYPOMETHYLATED PROMOTERS ALLOWED DISCRIMINATION OF CLL SAMPLES FROM HEALTHY CONTROLS. PROMOTER DNA METHYLATION PATTERNS WERE CONFIRMED IN AN INDEPENDENT PATIENT COHORT, WITH 11 MIRNAS CONSISTENTLY SHOWING AN INVERSE CORRELATION BETWEEN DNA METHYLATION STATUS AND EXPRESSION LEVEL. TOGETHER, OUR FINDINGS CHARACTERIZE THE ROLE OF EPIGENETIC CHANGES IN THE REGULATION OF MIRNA TRANSCRIPTION AND CREATE A REPOSITORY OF DISEASE-SPECIFIC PROMOTER REGIONS THAT MAY PROVIDE ADDITIONAL INSIGHTS INTO THE PATHOGENESIS OF CLL.	2012	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  
20 2847  28 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