1 3897 145 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	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        
2 6692  45 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	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       
3 4905  49 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 2234  36 EPIGENETIC MODIFICATIONS PRECEDE MOLECULAR ALTERATIONS AND DRIVE HUMAN HEPATOCARCINOGENESIS. DEVELOPMENT OF PRIMARY LIVER CANCER IS A MULTISTAGE PROCESS. DETAILED UNDERSTANDING OF SEQUENTIAL EPIGENETIC ALTERATIONS IS LARGELY MISSING. HERE, WE PERFORMED INFINIUM HUMAN METHYLATION 450K BEADCHIPS AND RNA-SEQ ANALYSES FOR GENOME-WIDE METHYLOME AND TRANSCRIPTOME PROFILING OF CIRRHOTIC LIVER (N = 7), LOW- (N = 4) AND HIGH-GRADE (N = 9) DYSPLASTIC LESIONS, AND EARLY (N = 5) AND PROGRESSED (N = 3) HEPATOCELLULAR CARCINOMAS (HCC) SYNCHRONOUSLY DETECTED IN 8 PATIENTS WITH HCC WITH CHRONIC HEPATITIS B INFECTION. INTEGRATIVE ANALYSES OF EPIGENETICALLY DRIVEN MOLECULAR CHANGES WERE IDENTIFIED AND VALIDATED IN 2 INDEPENDENT COHORTS COMPRISING 887 HCCS. MITOCHONDRIAL DNA SEQUENCING WAS FURTHER EMPLOYED FOR CLONALITY ANALYSES, INDICATING MULTICLONAL ORIGIN IN THE MAJORITY OF INVESTIGATED HCCS. ALTERATIONS IN DNA METHYLATION PROGRESSIVELY INCREASED FROM LIVER CIRRHOSIS (CL) TO DYSPLASTIC LESIONS AND REACHED A MAXIMUM IN EARLY HCCS. ASSOCIATED EARLY ALTERATIONS IDENTIFIED BY INGENUITY PATHWAY ANALYSIS (IPA) INVOLVED APOPTOSIS, IMMUNE REGULATION, AND STEMNESS PATHWAYS, WHILE LATE CHANGES CENTERED ON CELL SURVIVAL, PROLIFERATION, AND INVASION. WE FURTHER VALIDATED 23 PUTATIVE EPIDRIVERS WITH CONCOMITANT EXPRESSION CHANGES AND ASSOCIATED WITH OVERALL SURVIVAL. FUNCTIONALLY, STRIATIN 4 (STRN4) WAS DEMONSTRATED TO BE EPIGENETICALLY REGULATED, AND INHIBITION OF STRN4 SIGNIFICANTLY SUPPRESSED TUMORIGENICITY OF HCC CELL LINES. OVERALL, APPLICATION OF INTEGRATIVE GENOMIC ANALYSES DEFINES EPIGENETIC DRIVER ALTERATIONS AND PROVIDES PROMISING TARGETS FOR POTENTIALLY NOVEL THERAPEUTIC APPROACHES.	2021	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
5 2682  33 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	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         
6 3248  39 HEPATITIS B VIRUS GENOME ASYMMETRY IN HEPATOCELLULAR CARCINOMA. BACKGROUND: THE ASSOCIATION BETWEEN HEPATITIS B VIRUS (HBV) MUTATIONS AND HEPATOCARCINOGENESIS WERE REPORTED IN THE LITERATURE. PREFERENCE FOR G OVER C IN THE LEADING DNA STRAND HAS BEEN REPORTED TO ACCOUNT FOR THE ASYMMETRY IN NUCLEOTIDE (NT) COMPOSITION. THE AIM OF THIS STUDY WAS TO ANALYZE THE COMPLETE GENOME SEQUENCE AND COMPOSITIONAL ASYMMETRY OF HBV IN DIFFERENT STAGES OF HEPATITIS B. METHODS: FULL GENOME SEQUENCING OF 24 PATIENTS WITH CHRONIC HEPATITIS B, SOME OF WHOM ALSO HAD CIRRHOSIS AND HEPATOCELLULAR CARCINOMA (HCC) WAS PERFORMED. MUTATIONS ANALYSIS WAS IMPLEMENTED IN A COMPARISON WITH A HBV GENOTYPE D REFERENCE FROM AN INTERNATIONAL DNA DATABASE. CPGPROD, A WEB-BASED APPLICATION, WAS USED TO EVALUATE CG CONTENT AND PREDICT CPG ISLANDS. RESULTS: ALL STRAINS WERE 3182 BASE PAIRS (BP) IN LENGTH, EXCEPT FOR TWO CASES OF HCC IN WHICH 9 AND 21 NT, RESPECTIVELY, WERE DELETED IN PRES2. THE GENETIC RELATEDNESS OF THESE ISOLATES WAS 97%-100%. THERE WERE COMMON CPG-RICH REGIONS IN ALL 24 ISOLATED FULL GENOME SEQUENCES, HOWEVER A STRONG NEGATIVE GC SKEW FOR FORMING A CPG ISLAND IN THE MINUS STRAND WERE EXHIBITED IN OVERLAP WITH ENHANCER I IN THREE HCC PATIENTS, A CIRRHOTIC PATIENT AND THREE WITH CHRONIC HEPATITIS. CONCLUSION: THE HIGH PERCENTAGE OF SEQUENCE IDENTITY BETWEEN HBV ISOLATES IN OUR PATIENTS DEMONSTRATES THAT GENOMIC FACTORS, EXCEPT FOR GENOTYPE, ARE INVOLVED IN HEPATOCARCINOGENESIS. VARIATIONS IN GC CONTENT WHICH WERE CAUSED BY A DIFFERENT SPECTRUM OF MUTATIONS MAY AFFECT DNA COMPOSITIONAL ASYMMETRY AND EPIGENETIC MODIFICATION OF HBV DNA IN HCC.	2012	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             
7 1342  41 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	
                                                                                                                                                                  
8 3646  35 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	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
9 6488  47 TP53 R72P POLYMORPHISM MODULATES DNA METHYLATION IN HEPATOCELLULAR CARCINOMA. BACKGROUND: HEPATOCELLULAR CARCINOMA (HCC) IS CHARACTERIZED BY WIDESPREAD EPIDEMIOLOGICAL AND MOLECULAR HETEROGENEITY. PREVIOUS WORK SHOWED THAT IN THE WESTERN PART OF NORTH AFRICA, A REGION OF LOW INCIDENCE OF HCC, MUTATIONS ARE SCARCE FOR THIS TUMOR TYPE. AS EPIGENETIC CHANGES ARE CONSIDERED POSSIBLE SURROGATES TO MUTATIONS IN HUMAN CANCERS, WE DECIDED, THUS, TO CHARACTERIZE DNA METHYLATION IN HCC FROM NORTH-AFRICAN PATIENTS. METHODS: A SET OF 11 LOCI WAS INVESTIGATED IN A SERIES OF 45 TUMOR SPECIMENS USING METHYLATION-SPECIFIC AND COMBINED-BISULFITE RESTRICTION ASSAY PCR. RESULTS OBTAINED ON CLINICAL SAMPLES WERE SUBSEQUENTLY VALIDATED IN LIVER CANCER CELL LINES. RESULTS: DNA METHYLATION AT TUMOR SUPPRESSOR LOCI IS SIGNIFICANTLY HIGHER IN SAMPLES DISPLAYING CHROMOSOME INSTABILITY. MORE IMPORTANTLY, DNA METHYLATION WAS SIGNIFICANTLY HIGHER IN ARG/ARG WHEN COMPARED TO PRO/PRO GENOTYPE CARRIERS AT CODON 72 RS1042522 OF TP53 (65% VS 20% METHYLATED LOCI, P = 0.0006), A POLYMORPHISM ALREADY KNOWN TO AFFECT SOMATIC MUTATION RATE IN HUMAN CARCINOMAS. IN VITRO EXPERIMENTS IN CELL LINES INDICATED THAT ENZYMES CONTROLLING DNA METHYLATION WERE DIFFERENTIALLY REGULATED BY CODON 72 ARG OR PRO ISOFORMS OF P53. FURTHERMORE, THE ARG72-CARRYING VERSION OF P53 WAS SHOWN TO RE-METHYLATE DNA MORE RAPIDLY THAN THE PRO-HARBORING ISOFORM. FINALLY, PRO-CARRYING CELL LINES WERE SHOWN TO BE SIGNIFICANTLY MORE RESISTANT TO DECITABINE TREATMENT (TWO-FOLD, P = 0.005). CONCLUSIONS: OUR DATA SUGGEST THAT ARG72PRO POLYMORPHISM IN A WT P53 CONTEXT MAY ACT AS A PRIMARY DRIVER OF EPIGENETIC CHANGES IN HCC. IT SUGGESTS, IN ADDITION, THAT RS1042522 GENOTYPE MAY PREDICT SENSITIVITY TO EPIGENETIC-TARGETED THERAPY. THIS MODEL OF LIVER TUMORIGENESIS THAT ASSOCIATES LOW PENETRANCE GENETIC PREDISPOSITION TO EPIGENETIC CHANGES EMERGES FROM A REGION OF LOW HCC INCIDENCE AND IT MAY, THEREFORE, APPLY ESSENTIALLY TO POPULATION LIVING IN SIMILAR AREAS. SURVEYS ON POPULATIONS SUBMITTED TO HIGHLY MUTAGENIC CONDITIONS AS PERINATALLY-ACQUIRED CHRONIC HEPATITIS B OR AFLATOXIN B1 EXPOSURE REMAINED TO BE CONDUCTED TO VALIDATE OUR OBSERVATIONS AS A GENERAL MODEL.	2015	
                                                                             
10 2902  38 GENDER DIFFERENCES IN THE LIVERS OF PATIENTS WITH HEPATOCELLULAR CARCINOMA AND CHRONIC HEPATITIS C INFECTION. OBJECTIVES: A UNIQUE CAUSATIVE ASPECT OF HEPATOCELLULAR CARCINOMA (HCC) IS A GENDER DIFFERENCE IN ITS INCIDENCE. TO DETERMINE THE SPECIFIC FACTORS THAT CONTRIBUTE TO A MALE PREDOMINANCE, WE ANALYZED THE CLINICOPATHOLOGICAL FACTORS, AND GENETIC AND EPIGENETIC ALTERATIONS OF HCCS IN MALE AND FEMALE PATIENTS. METHODS: WE RETROSPECTIVELY ANALYZED THREE COHORTS OF PATIENTS: THE FIRST COHORT CONSISTED OF 547 PATIENTS IDENTIFIED WITH THE FIRST EVENT OF HCC, THE SECOND COHORT INCLUDED 176 HCC PATIENTS, AND THE THIRD 127 PATIENTS WITH CHRONIC HEPATITIS C (CHC). RESULTS: MALE PATIENTS WERE FOUND TO HAVE HCC MORE FREQUENTLY THAN FEMALE PATIENTS IN CASES OF NON-CIRRHOTIC LIVER (P = 0.0030 BY THE CHI(2) TEST), ESPECIALLY IN HEPATITIS C-POSITIVE CASES. HOWEVER, THERE WERE NO GENDER-SPECIFIC DIFFERENCES IN THE GENETIC AND EPIGENETIC ALTERATIONS OF CANCER-RELATED GENES. DEPOSITION OF IRON WAS MORE SEVERE IN MALE CHC PATIENTS THAN IN FEMALE PATIENTS. CONCLUSIONS: MALE PATIENTS WITH CHC DEVELOP HCC MORE FREQUENTLY WHEN THEY HAVE A NON-CIRRHOTIC LIVER THAN DO FEMALE PATIENTS. THIS GENDER DIFFERENCE COULD BE, AT LEAST PARTIALLY, ATTRIBUTED TO A DIFFERENT DEGREE OF IRON DEPOSITION, WHICH CONTRIBUTES TO THE DEVELOPMENT OF HCC IN THE ABSENCE OF LIVER CIRRHOSIS IN MEN WITH CHC.	2012	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    
11   59  39 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	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    
12  332  39 ALTERATION OF EPIGENETIC PROFILE IN HUMAN HEPATOCELLULAR CARCINOMA AND ITS CLINICAL IMPLICATIONS. HEPATOCELLULAR CARCINOMA (HCC) IS A COMMON CANCER WORLDWIDE AND DEVELOPS AGAINST A BACKGROUND OF CHRONIC LIVER DAMAGE. A VARIETY OF HCC-RELATED GENES ARE KNOWN TO BE ALTERED BY GENETIC AND EPIGENETIC MECHANISMS. THEREFORE, INFORMATION REGARDING ALTERATION OF THE GENETIC AND EPIGENETIC PROFILES IN HCC IS ESSENTIAL FOR UNDERSTANDING THE BIOLOGY OF THIS TYPE OF TUMOR. METHYLATION AT CPG SITES IN GENE PROMOTERS IS KNOWN TO AFFECT THE TRANSCRIPTION OF THE CORRESPONDING GENES. ABNORMAL REGIONAL HYPERMETHYLATION IS OBSERVED IN THE 5' REGION OF SEVERAL TUMOR SUPPRESSOR GENES (TSGS) IN HCC, AND THIS HYPERMETHYLATION MAY PROMOTE CARCINOGENESIS THROUGH THE TRANSCRIPTIONAL INACTIVATION OF DOWNSTREAM TSGS. THE DNA DAMAGE INDUCED BY OXIDATION IS A TRIGGER OF ABNORMAL DNA METHYLATION AND INACTIVATION OF TSGS THROUGH RECRUITMENT OF THE POLYCOMB REPRESSIVE COMPLEX TO THE PROMOTER SEQUENCE. THUS, OXIDATIVE STRESS MAY BE RESPONSIBLE FOR THE EMERGENCE OF HCC FROM CHRONIC HEPATITIS AND LIVER CIRRHOSIS THROUGH THE EPIGENETIC ALTERATION OF TSGS. THERE HAVE BEEN SEVERAL ATTEMPTS TO APPLY EPIGENETIC INFORMATION TO THE DIAGNOSIS AND TREATMENT OF HCC. THE PREDICTIVE VALUE OF SELECTED METHYLATION EVENTS ON SURVIVAL IN HCC PATIENTS HAS BEEN REPORTED, AND THE METHYLATION PROFILE OF BACKGROUND LIVER COULD BE ASSOCIATED WITH RECURRENCE-FREE SURVIVAL OF HCC PATIENTS WHO HAVE UNDERGONE HEPATECTOMY. ANOTHER STUDY DETECTED METHYLATED DNA FROM HCC CELLS IN SERUM, AND THE CIRCULATING TUMOR DNA WAS REGARDED AS A POTENTIAL TUMOR MARKER. IN ADDITION, SEVERAL TRIALS OF HCC THERAPY HAVE TARGETED THE EPIGENETIC MACHINERY AND WERE BASED UPON COMPREHENSIVE ANALYSES OF DNA METHYLATION OF THIS TYPE OF TUMOR. HERE, WE PRESENT AN OVERVIEW OF RESEARCH REGARDING DNA METHYLATION STATUS IN HUMAN HCC AND DESCRIBE THE CLINICAL APPLICATION OF EPIGENETIC INFORMATION TO HCC.	2014	
                                                                                                                                                                                                                                                                                                                                                                  
13 1582  34 DNA METHYLATION PROFILES IN PRECANCEROUS TISSUE AND CANCERS: CARCINOGENETIC RISK ESTIMATION AND PROGNOSTICATION BASED ON DNA METHYLATION STATUS. ALTERATIONS IN DNA METHYLATION, WHICH ARE ASSOCIATED WITH DNA METHYLTRANSFERASE ABNORMALITIES AND RESULT IN SILENCING OF TUMOR-RELATED GENES AND CHROMOSOMAL INSTABILITY, ARE INVOLVED EVEN IN PRECANCEROUS CHANGES IN VARIOUS ORGANS. DNA METHYLATION ALTERATIONS ALSO ACCOUNT FOR THE HISTOLOGICAL HETEROGENEITY AND CLINICOPATHOLOGICAL DIVERSITY OF HUMAN CANCERS. THEREFORE, WE HAVE ANALYZED DNA METHYLATION ON A GENOME-WIDE SCALE IN CLINICAL TISSUE SAMPLES. OUR APPROACH USING THE BACTERIAL ARTIFICIAL CHROMOSOME ARRAY-BASED METHYLATED CPG ISLAND AMPLIFICATION METHOD HAS REVEALED THAT DNA METHYLATION ALTERATIONS CORRELATED WITH THE FUTURE DEVELOPMENT OF MORE MALIGNANT CANCERS ARE ALREADY ACCUMULATED AT THE PRECANCEROUS STAGE IN THE KIDNEY, LIVER AND URINARY TRACT. DNA METHYLATION PROFILES AT PRECANCEROUS STAGES ARE BASICALLY INHERITED BY THE CORRESPONDING CANCERS DEVELOPING IN INDIVIDUAL PATIENTS. SUCH DNA METHYLATION ALTERATIONS MAY CONFER VULNERABILITY TO FURTHER GENETIC AND EPIGENETIC ALTERATIONS, GENERATE MORE MALIGNANT CANCERS, AND THUS DETERMINE PATIENT OUTCOME. ON THE BASIS OF BACTERIAL ARTIFICIAL CHROMOSOME ARRAY-BASED METHYLATED CPG ISLAND AMPLIFICATION DATA, INDICATORS FOR CARCINOGENETIC RISK ESTIMATION HAVE BEEN ESTABLISHED USING LIVER TISSUE SPECIMENS FROM PATIENTS WITH HEPATITIS VIRUS INFECTION, CHRONIC HEPATITIS AND LIVER CIRRHOSIS OR HISTOLOGICALLY NORMAL UROTHELIA, AND FOR PROGNOSTICATION USING BIOPSY OR SURGICALLY RESECTED SPECIMENS FROM PATIENTS WITH RENAL CELL CARCINOMA, HEPATOCELLULAR CARCINOMA AND UROTHELIAL CARCINOMA. SUCH GENOME-WIDE DNA METHYLATION PROFILING HAS NOW FIRMLY ESTABLISHED THE CLINICAL RELEVANCE OF TRANSLATIONAL EPIGENETICS.	2010	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             
14 4677  45 NEW LNCRNAS IN CHRONIC HEPATITIS C PROGRESSION: FROM FIBROSIS TO HEPATOCELLULAR CARCINOMA. HEPATOCELLULAR CARCINOMA (HCC) IS THE THIRD LEADING CAUSE OF CANCER-RELATED DEATH IN THE WORLD, AND ABOUT 80% OF THE CASES ARE ASSOCIATED WITH HEPATITIS B OR C. GENETIC AND EPIGENETIC ALTERATIONS ARE ACCUMULATED OVER DECADES OF CHRONIC INJURY AND MAY AFFECT THE FUNCTIONING OF TUMOR SUPPRESSOR GENES AND PROTOONCOGENES. STUDIES HAVE EVIDENCED THE ROLE OF LONG NON-CODING RNAS (LNCRNA) WITH ONCOGENIC OR TUMOR SUPPRESSOR ACTIVITIES, SUGGESTING A GREAT POTENTIAL IN THE TREATMENT, DIAGNOSIS OR INDICATOR OF PROGNOSIS IN CANCER. IN THIS CONTEXT, THE AIM OF THIS STUDY WAS TO EVALUATE THE GLOBAL EXPRESSION PROFILE LNCRNA IN HEPATIC TISSUE SAMPLES WITH DIFFERENT STAGES OF FIBROSIS ASSOCIATED WITH CHRONIC HEPATITIS C, HCC AND NORMAL LIVER, IN ORDER TO IDENTIFY NEW LNCRNAS THAT COULD CONTRIBUTE TO STUDY THE PROGRESSION OF HEPATIC FIBROSIS TO HCC ASSOCIATED WITH CHRONIC HEPATITIS C. RNA-SEQ WAS PERFORMED ON ILLUMINA NEXTSEQ PLATFORM TO IDENTIFY LNCRNAS EXPRESSED DIFFERENTLY IN 15 PATIENTS WITH CHRONIC HEPATITIS C, THREE PATIENTS WITH HCC AND THREE NORMAL LIVER SPECIMENS. WHEN THE PATHOLOGICAL TISSUES (FIBROSIS AND CARCINOMA) WERE COMPARED TO NORMAL HEPATIC TISSUE, WERE IDENTIFIED 2, 6 E 34 DIFFERENTIALLY EXPRESSED LNCRNAS IN MODERATE FIBROSIS, ADVANCED FIBROSIS AND HCC, RESPECTIVELY. THE CARCINOMA GROUP HAD THE HIGHEST PROPORTION OF DIFFERENTIALLY EXPRESSED LNCRNA (34) AND OF THESE, 29 WERE EXCLUSIVE IN THIS TYPE OF TISSUE. A HEAT MAP OF THE DEREGULATED LNCRNA REVEALED DIFFERENT EXPRESSION PATTERNS ALONG THE PROGRESSION OF FIBROSIS TO HCC. THE RESULTS SHOWED THE DEREGULATION OF SOME LNCRNA ALREADY CLASSIFIED AS TUMOR SUPPRESSORS IN HCC AND OTHER CANCERS, AS WELL AS SOME UNPUBLISHED LNCRNA WHOSE FUNCTION IS UNKNOWN. SOME OF THESE LNCRNAS ARE DYSREGULATED SINCE THE EARLY STAGES OF LIVER INJURY IN PATIENTS WITH HEPATITIS C, OTHERS OVEREXPRESSED ONLY IN TUMOR TISSUE, INDICATING THEMSELVES AS CANDIDATES OF MARKERS OF FIBROSIS PROGRESSION OR TUMOR, WITH POTENTIAL CLINICAL APPLICATIONS IN PROGNOSIS AS WELL AS A THERAPEUTIC TARGET. ALTHOUGH THERE ARE ALREADY STUDIES ON LNCRNA IN HEPATOCELLULAR CARCINOMA, THIS IS THE FIRST STUDY CONDUCTED IN SAMPLES EXCLUSIVELY OF HCV-RELATED LIVER AND HCV HCC.	2020	

15  153  46 ABERRANT METHYLATION OF MULTIPLE TUMOR SUPPRESSOR GENES IN AGING LIVER, CHRONIC HEPATITIS, AND HEPATOCELLULAR CARCINOMA. ABERRANT DNA METHYLATION IS AN IMPORTANT EPIGENETIC ALTERATION IN HEPATOCELLULAR CARCINOMA (HCC). HOWEVER, THE MOLECULAR PROCESSES UNDERLYING THE METHYLATOR PHENOTYPE AND THE CONTRIBUTION OF HEPATITIS VIRUSES ARE POORLY UNDERSTOOD. THE CURRENT STUDY IS A COMPREHENSIVE METHYLATION ANALYSIS OF HUMAN LIVER TISSUE SPECIMENS. A TOTAL OF 176 LIVER TISSUES, INCLUDING 77 PAIRS OF HCCS AND MATCHING NONCANCEROUS LIVER AND 22 NORMAL LIVERS, WERE ANALYZED FOR METHYLATION. METHYLATION OF 19 EPIGENETIC MARKERS WAS QUANTIFIED, AND THE RESULTS WERE CORRELATED WITH DIFFERENT DISEASE STATES AND THE PRESENCE OR ABSENCE OF HEPATITIS B VIRUS (HBV) AND HEPATITIS C VIRUS (HCV) INFECTIONS. BASED ON METHYLATION PROFILES, THE 19 LOCI WERE CATEGORIZED INTO 3 GROUPS. NORMAL LIVER TISSUES SHOWED METHYLATION PRIMARILY IN GROUP 1 LOCI (HIC-1, CASP8, GSTP1, SOCS1, RASSF1A, P16, APC), WHICH WAS SIGNIFICANTLY HIGHER THAN GROUP 2 (CDH1, RUNX3, RIZ1, SFRP2, MINT31) AND GROUP 3 MARKERS (COX2, MINT1, CACNA1G, RASSF2, MINT2, REPRIMO, DCC) (P < 0.0001). NONCANCEROUS LIVERS DEMONSTRATED INCREASED METHYLATION IN BOTH GROUP 1 AND GROUP 2 LOCI. METHYLATION WAS SIGNIFICANTLY MORE ABUNDANT IN HCV-POSITIVE LIVERS COMPARED WITH NORMAL LIVER TISSUES. CONVERSELY, HCC SHOWED FREQUENT METHYLATION AT EACH LOCUS INVESTIGATED IN ALL 3 GROUPS. HOWEVER, THE GROUP 3 LOCI SHOWED MORE DENSE AND FREQUENT METHYLATION IN HCV-POSITIVE CANCERS COMPARED WITH BOTH HBV-POSITIVE CANCERS AND VIRUS-NEGATIVE CANCERS (P < 0.0001). CONCLUSION: METHYLATION IN HCC IS FREQUENT BUT OCCURS IN A GENE-SPECIFIC AND DISEASE-SPECIFIC MANNER. METHYLATION PROFILING ALLOWED US TO DETERMINE THAT ABERRANT METHYLATION IS COMMONLY PRESENT IN NORMAL AGING LIVERS, AND SEQUENTIALLY PROGRESSES WITH ADVANCING STAGES OF CHRONIC VIRAL INFECTION. FINALLY, OUR DATA PROVIDE EVIDENCE THAT HCV INFECTION MAY ACCELERATE THE METHYLATION PROCESS AND SUGGESTS A CONTINUUM OF INCREASING METHYLATION WITH PERSISTENT VIRAL INFECTION AND CARCINOGENESIS IN THE LIVER.	2008	
                                                                                                                                                                                               
16 1617  48 DNA METHYLTRANSFERASE EXPRESSION AND DNA METHYLATION IN HUMAN HEPATOCELLULAR CARCINOMA AND THEIR CLINICOPATHOLOGICAL CORRELATION. ABERRANT DNA METHYLATION ON CPG ISLANDS IS ONE OF THE MOST CONSISTENT EPIGENETIC CHANGES IN HUMAN CANCERS, AND THE METHYLATION PROCESS IS CATALYZED BY DNA METHYLTRANSFERASE (DNMT). WE EVALUATED I) THE MRNA LEVELS OF THREE DNMTS; DNMT1, DNMT3A AND DNMT3B, IN 25 HEPATOCELLULAR CARCINOMAS (HCCS), IN THEIR CORRESPONDING NON-CANCEROUS LIVER TISSUES AND IN 7 NORMAL LIVERS BY USING REAL-TIME REVERSE TRANSCRIPTASE-POLYMERASE CHAIN REACTION; II) NUCLEAR EXPRESSION OF DNMT1 AND DNMT3A PROTEINS IN THE HCCS BY IMMUNOHISTOCHEMISTRY, III) THE METHYLATION STATUS OF 5 GENES; P16, P15, E-CADHERIN, HIC-1 AND RASSF1A IN THE SAME TISSUES, AND IV) THE RELATIONSHIPS BETWEEN THE ABOVE RESULTS AND THE CLINICOPATHOLOGICAL CHARACTERISTICS, INCLUDING PROGNOSIS. THE DIFFERENCES IN MRNA EXPRESSION LEVELS FOR DNMT1, DNMT3A AND DNMT3B WERE STATISTICALLY SIGNIFICANT BETWEEN HCC AND NORMAL LIVERS (P<0.001), HCC AND CHRONIC HEPATITIS (P<0.001) AND HCC AND CIRRHOSIS (P<0.001). AN INCREASE IN MRNA EXPRESSION LEVELS OF >4-FOLD FOR DNMT3B IN HCCS WAS SIGNIFICANTLY ASSOCIATED WITH A POORER OVERALL SURVIVAL (P=0.027) AND SHORTER METASTASIS-FREE SURVIVAL (P=0.0299). A POORER RECURRENCE-FREE SURVIVAL WAS NOTED IN HCCS WITH A >4-FOLD INCREASE IN DNMT3A MRNA (P=0.0120). THE AVERAGE NUMBERS OF METHYLATED GENES WERE 0, 1.27, 1.38 AND 2.72 FOR NORMAL LIVERS, CHRONIC HEPATITIS, CIRRHOSIS AND HCCS, RESPECTIVELY, AND THIS PROGRESSIVE INCREASE FROM NORMAL LIVERS TO CHRONIC HEPATITIS/CIRRHOSIS THROUGH HCC MAY SUGGEST THAT TUMOR SUPPRESSOR GENE METHYLATION IS AN EARLY EVENT IN HEPATOCARCINOGENESIS. THESE RESULTS FIRST SUGGEST THAT HEPATOCARCINOGENESIS INVOLVES AN INCREASED EXPRESSION OF DNMT1, DNMT3A AND DNMT3B MRNA AND A PROGRESSIVE INCREASE IN THE NUMBER OF METHYLATED GENES FROM NORMAL LIVER, CHRONIC HEPATITIS/CIRRHOSIS TO HCC AND SECONDLY THAT AN INCREASE IN THE DNMT3A AND DNMT3B MRNA LEVELS IN HCCS RELATIVE TO THEIR NON-CANCEROUS TISSUES MAY BE A PREDICTOR OF POOR SURVIVAL.	2007	
                                                                                                                                                                                                                   
17 3067  36 GENOME-WIDE DNA METHYLATION PROFILES IN PRECANCEROUS CONDITIONS AND CANCERS. ALTERATIONS OF DNA METHYLATION, WHICH RESULT IN CHROMOSOMAL INSTABILITY AND SILENCING OF TUMOR-RELATED GENES, ARE AMONG THE MOST CONSISTENT EPIGENETIC CHANGES OBSERVED IN HUMAN CANCERS. ANALYSIS OF TISSUE SPECIMENS HAS REVEALED THAT DNA METHYLATION ALTERATIONS PARTICIPATE IN MULTISTAGE CARCINOGENESIS, EVEN FROM THE EARLY AND PRECANCEROUS STAGES, ESPECIALLY IN ASSOCIATION WITH CHRONIC INFLAMMATION AND/OR PERSISTENT VIRAL INFECTION, SUCH AS CHRONIC HEPATITIS OR LIVER CIRRHOSIS RESULTING FROM INFECTION WITH HEPATITIS B OR C VIRUS. DNA METHYLATION ALTERATIONS CAN ACCOUNT FOR THE HISTOLOGICAL HETEROGENEITY AND CLINICOPATHOLOGICAL DIVERSITY OF HUMAN CANCERS. OVEREXPRESSION OF DNA METHYLTRANSFERASE 1 IS NOT A SECONDARY RESULT OF INCREASED CELL PROLIFERATIVE ACTIVITY, BUT IS SIGNIFICANTLY CORRELATED WITH ACCUMULATION OF DNA HYPERMETHYLATION IN CPG ISLANDS OF TUMOR-RELATED GENES. ALTERATION OF DNA METHYLTRANSFERASE 3B SPLICING MAY RESULT IN CHROMOSOMAL INSTABILITY THROUGH DNA HYPOMETHYLATION IN PERICENTROMERIC SATELLITE REGIONS. GENOME-WIDE ANALYSIS OF DNA METHYLATION STATUS HAS REVEALED THAT THE DNA METHYLATION PROFILE AT THE PRECANCEROUS STAGE IS BASICALLY INHERITED BY THE CORRESPONDING CANCERS DEVELOPING IN INDIVIDUAL PATIENTS. DNA METHYLATION STATUS IS NOT SIMPLY ALTERED AT THE PRECANCEROUS STAGE; RATHER, DNA METHYLATION ALTERATIONS AT THE PRECANCEROUS STAGE MAY CONFER VULNERABILITY TO FURTHER GENETIC AND EPIGENETIC ALTERATIONS, GENERATE MORE MALIGNANT CANCERS, AND THUS DETERMINE PATIENT OUTCOME. THEREFORE, GENOME-WIDE DNA METHYLATION PROFILING MAY PROVIDE OPTIMAL INDICATORS FOR CARCINOGENETIC RISK ESTIMATION AND PROGNOSTICATION, AND THUS PROVIDE AN AVENUE FOR CANCER PREVENTION AND THERAPY ON AN INDIVIDUAL BASIS.	2010	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      
18 6723  38 VITAMIN D RECEPTOR GENE METHYLATION IN HEPATOCELLULAR CARCINOMA. WORLDWIDE, HEPATOCELLULAR CARCINOMA (HCC) IS THE MAJOR SUBTYPE OF PRIMARY LIVER CANCERS. HCC IS TYPICALLY DIAGNOSED LATE IN ITS COURSE. WITH RESPECT TO CANCER, THE GENOMIC ACTIONS OF VITAMIN D ARE MEDIATED THROUGH BINDING TO THE VITAMIN D RECEPTOR (VDR), WHICH ALLOWS IT TO MODULATE THE EXPRESSION OF GENES IN A CELL-AND TISSUE-SPECIFIC MANNER. EPIGENETICS IS A RAPIDLY EVOLVING FIELD OF GENETIC STUDY APPLICABLE TO HCC. CHANGES IN DNA METHYLATION PATTERNS ARE THOUGHT TO BE EARLY EVENTS IN HEPATOCARCINOGENESIS. CURCUMIN HAS GREAT POTENTIAL AS AN EPIGENETIC AGENT. ACCORDINGLY, THE CURRENT STUDY HAS BEEN DESIGNED TO STUDY THE METHYLATION STATUS OF VDR GENE PROMOTER FOR THE FIRST TIME IN HCC AIMING TO FIND ITS CLINICAL SIGNIFICANCE AND POTENTIAL SCREENING ROLE IN CHRONIC LIVER DISEASE (CLD). ADDITIONALLY, WE AIMED TO INVESTIGATE, THE EFFECT OF CURCUMIN ON HCC CELL LINE, AIMING TO DISCOVER NEW THERAPEUTIC TARGETS THROUGH EPIGENETICS. THIS STUDY WAS CONDUCTED ON 45 FORMALIN-FIXED, PARAFFIN-EMBEDDED LIVER TISSUE BLOCKS INCLUDING 15 HCC SAMPLES (GROUP A), 15 CLD SAMPLES (GROUP B) AND 15 APPARENTLY NORMAL TISSUE TAKEN FROM AROUND BENIGN LESIONS (GROUP C). METHYLATION SPECIFIC RESTRICTION DIGESTION AND QPCR WERE DONE ON ALL SAMPLES AFTER DNA EXTRACTION. THE PERCENTAGE OF VDR GENE PROMOTER METHYLATION WAS SIGNIFICANTLY HIGHER IN THE HCC GROUP COMPARED TO BOTH CLD AND CONTROL GROUPS (P < 0.01). VDR PROMOTER METHYLATION BY (MS-QPCR) WAS DECREASED AND THE RELATIVE EXPRESSION OF VDR BY (QRT-PCR) WAS MARKEDLY INCREASED IN A DOSE-DEPENDENT FASHION IN CELLS GROWN IN CURCUMIN-ADEQUATE MEDIUM. IN CONCLUSION, THIS STUDY MAY OPEN A NEW GATE FOR THE USE OF VDR PROMOTER METHYLATION AS A POTENTIAL BIOMARKER IN HCC.	2018	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       
19 5844  40 STUDY OF PROMOTER HYPOMETHYLATION PROFILES OF RAS ONCOGENES IN HEPATOCELLULAR CARCINOMA DERIVED FROM HEPATITIS C VIRUS GENOTYPE 3A IN PAKISTANI POPULATION. EPIGENETIC MODIFICATIONS SUCH AS DNA METHYLATION CONTRIBUTE TO PROGRESSION OF HEPATITIS C VIRUS (HCV) INFECTION TO LIFE-THREATENING HEPATOCELLULAR CARCINOMA (HCC) BY PROMOTING THE SILENCING OF TUMOR SUPPRESSOR GENES THROUGH DNA HYPERMETHYLATION AND BY CAUSING GENOMIC INSTABILITY THROUGH GLOBAL HYPOMETHYLATION. HOWEVER FEW STUDIES HAVE ADDRESSED THE PROMOTER REGION HYPOMETHYLATION STATUS OF THE ONCOGENES INVOLVED IN HCV DERIVED HCC. IN THIS STUDY, WE ANALYZED THE PROMOTER REGION METHYLATION PATTERN OF RAS ONCOGENES (HRAS, KRAS, AND NRAS) USING METHYLATION-SPECIFIC PCR FOR 50 CHRONIC HCV PATIENTS INFECTED WITH GENOTYPE 3A (27 HCC PATIENTS AND 23 CONTROL NON-HCC PATIENTS). METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION ANALYSIS REVEALED THAT THE NRAS ONCOGENE PROMOTER (P = .0025) WAS SIGNIFICANTLY HYPOMETHYLATED IN HCC PATIENTS COMPARED TO THE NON-HCC PATIENTS SUGGESTING ITS CONTRIBUTION TO THE PROGRESSION OF HCV TOWARDS HCC. TO IDENTIFY THE AGENT FOR ALTERATION IN THE RAS ONCOGENE EXPRESSION, 7 HCV GENES WERE EXPRESSED IN THE HUH-7 CELL LINE FOLLOWED BY MEASUREMENT OF THE NRAS EXPRESSION LEVEL IN HUH-7 BY A QUANTITATIVE REAL-TIME POLYMERASE CHAIN REACTION. AN INCREASE IN THE MESSENGER RNA LEVEL OF THE NRAS GENE WAS DETECTED WHEN HUH-7 WERE TRANSFECTED WITH CORE, NS5A, AND NS2 GENES. OUR FINDINGS SUGGEST THE INVOLVEMENT OF NRAS ONCOGENE IN THE PATHOGENESIS OF HCV3A DERIVED HCC IN PAKISTANI POPULATION AND ALSO IDENTIFIES THE HCV GENES RESPONSIBLE FOR ITS ENHANCED EXPRESSION. OUR STUDY RAISES THE HYPOTHESIS THAT A SINGLE HCV GENE MAY INCREASE THE CHANCES OF MALIGNANCY. THEREFORE, OUR STUDY MAY HAVE IDENTIFIED A USEFUL EPIGENETIC BIOMARKER OF HCC PROGRESSION IN HCV PATIENTS AND MAY HELP TO DEVELOP NOVEL DIAGNOSTIC TOOLS.	2018	
                                                                                                                                                                                                                                                                                                                                                                                                                
20 3825  48 INVESTIGATION OF CTNNB1 GENE MUTATIONS AND EXPRESSION IN HEPATOCELLULAR CARCINOMA AND CIRRHOSIS IN ASSOCIATION WITH HEPATITIS B VIRUS INFECTION. HEPATITIS B VIRUS (HBV), ALONG WITH HEPATITIS C VIRUS CHRONIC INFECTION, REPRESENTS A MAJOR RISK FACTOR FOR HEPATOCELLULAR CARCINOMA (HCC) DEVELOPMENT. HOWEVER, MOLECULAR MECHANISMS INVOLVED IN THE DEVELOPMENT OF HCC ARE NOT YET COMPLETELY UNDERSTOOD. RECENT STUDIES HAVE INDICATED THAT MUTATIONS IN CTNNB1 GENE ENCODING FOR BETA-CATENIN PROTEIN LEAD TO ABERRANT ACTIVATION OF THE WNT/ BETA-CATENIN PATHWAY. THE MUTATIONS IN TURN ACTIVATE SEVERAL DOWNSTREAM GENES, INCLUDING C-MYC, PROMOTING THE NEOPLASTIC PROCESS. THE PRESENT STUDY EVALUATED THE MUTATIONAL PROFILE OF THE CTNNB1 GENE AND EXPRESSION LEVELS OF CTNNB1 AND C-MYC GENES IN HBV-RELATED HCC, AS WELL AS IN CIRRHOTIC AND CONTROL TISSUES. MUTATIONAL ANALYSIS OF THE BETA-CATENIN GENE AND HBV GENOTYPING WERE CONDUCTED BY DIRECT SEQUENCING. EXPRESSION OF BETA-CATENIN AND C-MYC GENES WAS ASSESSED USING REAL-TIME PCR. AMONG THE HCC CASES, 18.1% SHOWED MISSENSE POINT MUTATION IN EXON 3 OF CTNNB1, MORE FREQUENTLY IN CODONS 32, 33, 38 AND 45. THE FREQUENCY OF MUTATION IN THE HOTSPOTS OF EXON 3 WAS SIGNIFICANTLY HIGHER IN NON-VIRAL HCCS (29.4%) RATHER THAN HBV-RELATED CASES (12.7%, P = 0.021). THE EXPRESSION OF BETA-CATENIN AND C-MYC GENES WAS FOUND UPREGULATED IN CIRRHOTIC TISSUES IN ASSOCIATION WITH HBV INFECTION. MUTATIONS AT BOTH PHOSPHORYLATION AND NEIGHBORING SITES WERE ASSOCIATED WITH INCREASED ACTIVITY OF THE WNT PATHWAY. THE RESULTS DEMONSTRATED THAT MUTATED BETA-CATENIN CAUSED ACTIVATION OF THE WNT PATHWAY, BUT THE RATE OF CTNNB1 GENE MUTATIONS WAS NOT RELATED TO HBV INFECTION. HBV FACTORS MAY DEREGULATE THE WNT PATHWAY BY CAUSING EPIGENETIC ALTERATIONS IN THE HBV-RELATED HCC.	2020