1 6539 126 TRANSCRIPTIONAL VARIATIONS IN THE WIDER PERITUMORAL TISSUE ENVIRONMENT OF PANCREATIC CANCER. TRANSCRIPTIONAL PROFILING WAS PERFORMED ON 452 RNA PREPARATIONS ISOLATED FROM VARIOUS TYPES OF PANCREATIC TISSUE FROM TUMOUR PATIENTS AND HEALTHY DONORS, WITH A PARTICULAR FOCUS ON PERITUMORAL SAMPLES. PANCREATIC DUCTAL ADENOCARCINOMAS (PDAC) AND CYSTIC TUMOURS WERE MOST DIFFERENT IN THESE NON-TUMOROUS TISSUES SURROUNDING THEM, WHEREAS THE ACTUAL TUMOURS EXHIBITED RATHER SIMILAR TRANSCRIPT PATTERNS. THE ENVIRONMENT OF CYSTIC TUMOURS WAS TRANSCRIPTIONALLY NEARLY IDENTICAL TO NORMAL PANCREAS TISSUE. IN CONTRAST, THE TISSUE AROUND PDAC BEHAVED A LOT LIKE THE TUMOUR, INDICATING SOME KIND OF FIELD DEFECT, WHILE SHOWING FAR LESS MOLECULAR RESEMBLANCE TO BOTH CHRONIC PANCREATITIS AND HEALTHY TISSUE. THIS SUGGESTS THAT THE MAJOR PATHOGENIC DIFFERENCE BETWEEN CYSTIC AND DUCTAL TUMOURS MAY BE DUE TO THEIR CELLULAR ENVIRONMENT RATHER THAN THE FEW VARIATIONS BETWEEN THE TUMOURS. LACK OF CORRELATION BETWEEN DNA METHYLATION AND TRANSCRIPT LEVELS MAKES IT UNLIKELY THAT THE OBSERVED FIELD DEFECT IN THE PERITUMORAL TISSUE OF PDAC IS CONTROLLED TO A LARGE EXTENT BY SUCH EPIGENETIC REGULATION. FUNCTIONALLY, A STRIKINGLY LARGE NUMBER OF AUTOPHAGY-RELATED TRANSCRIPTS WAS CHANGED IN BOTH PDAC AND ITS PERITUMORAL TISSUE, BUT NOT IN OTHER PANCREATIC TUMOURS. A TRANSCRIPTION SIGNATURE OF 15 AUTOPHAGY-RELATED GENES WAS ESTABLISHED THAT PERMITS A PROGNOSIS OF SURVIVAL WITH HIGH ACCURACY AND INDICATES THE ROLE OF AUTOPHAGY IN TUMOUR BIOLOGY. 2018 2 6529 34 TRANSCRIPTIONAL DOWN-REGULATION OF THE WNT ANTAGONIST SFRP1 IN HAEMATOPOIETIC CELLS OF PATIENTS WITH DIFFERENT RISK TYPES OF MDS. SECRETED FRIZZLED RELATED PROTEIN 1 (SFRP1) IS AN EXTRACELLULAR ANTAGONIST OF THE WNT SIGNALLING PATHWAY THAT PLAYS AN IMPORTANT ROLE IN THE PATHOGENESIS OF SOLID TUMOURS AND HAEMATOPOIETIC MALIGNANCIES. SFRP1 HAS BEEN OBSERVED TO BE TRANSCRIPTIONALLY DOWN-REGULATED DUE TO HYPERMETHYLATION IN ACUTE AND CHRONIC LEUKAEMIA, BUT SO FAR NOT IN MYELODYSPLASTIC SYNDROME (MDS). MOREOVER, IT HAS BEEN SHOWN THAT THE EPIGENETIC INACTIVATION OF SFRP1 CORRELATES WITH AN OVEREXPRESSION OF THE WNT RECEPTOR FRIZZLED 3 (FZD3) IN ACUTE LEUKAEMIA. USING REAL-TIME QUANTITATIVE REVERSE TRANSCRIPTION POLYMERASE CHAIN REACTION (RT-PCR) WE EXAMINED MRNA EXPRESSION OF SFRP1 AND FZD3 IN BONE MARROW CELLS DERIVED FROM 121 PATIENTS WITH DIFFERENT RISK TYPES OF MDS, ACUTE MYELOID LEUKAEMIA (AML) AND ACUTE LYMPHOBLASTIC LEUKAEMIA (ALL). WE EMPLOYED PYROSEQUENCING TO QUANTIFY PROMOTER DNA METHYLATION IN MDS AND ACUTE LEUKAEMIA. WE DETECTED SIGNIFICANT LOWER MRNA TRANSCRIPTION OF SFRP1 IN MDS COMPARED TO HEALTHY INDIVIDUALS. HOWEVER, DNA SEQUENCE MUTATIONS OR FREQUENT ELEVATED DNA METHYLATION LEVELS OF THE SFRP1 PROMOTER COULD NOT BE OBSERVED IN MDS BUT IN AML AND ALL AS PREVIOUSLY REPORTED. THE EXPRESSION LEVELS OF FZD3 WERE UP-REGULATED IN BOTH ACUTE LEUKAEMIA AND MDS. OUR DATA SHOW A SIGNIFICANT TRANSCRIPTIONAL DOWN-REGULATION OF SFRP1 AS A COMMON EVENT IN AML, ALL AND - AS DEMONSTRATED FOR THE FIRST TIME - IN MDS. AN INACTIVATION OF SFRP1 AND THE TRANSCRIPTIONAL UP-REGULATION OF FZD3 SEEM TO BE ASSOCIATED WITH AN ACTIVATION OF THE WNT SIGNALLING PATHWAY IN THESE HAEMATOPOIETIC DISEASES. 2010 3 2087 30 EPIGENETIC DYSREGULATION OF ID4 PREDICTS DISEASE PROGRESSION AND TREATMENT OUTCOME IN MYELOID MALIGNANCIES. PROMOTER HYPERMETHYLATION-MEDIATED INACTIVATION OF ID4 PLAYS A CRUCIAL ROLE IN THE DEVELOPMENT OF SOLID TUMOURS. THIS STUDY AIMED TO INVESTIGATE ID4 METHYLATION AND ITS CLINICAL RELEVANCE IN MYELOID MALIGNANCIES. ID4 HYPERMETHYLATION WAS ASSOCIATED WITH HIGHER IPSS SCORES, BUT WAS NOT AN INDEPENDENT PROGNOSTIC BIOMARKER AFFECTING OVERALL SURVIVAL (OS) IN MYELODYSPLASTIC SYNDROME (MDS). HOWEVER, ID4 HYPERMETHYLATION CORRELATED WITH SHORTER OS AND LEUKAEMIA-FREE SURVIVAL (LFS) TIME AND ACTED AS AN INDEPENDENT RISK FACTOR AFFECTING OS IN ACUTE MYELOID LEUKAEMIA (AML). MOREOVER, ID4 METHYLATION WAS SIGNIFICANTLY DECREASED IN THE FOLLOW-UP PAIRED AML PATIENTS WHO ACHIEVED COMPLETE REMISSION (CR) AFTER INDUCTION THERAPY. IMPORTANTLY, ID4 METHYLATION WAS INCREASED DURING MDS PROGRESSION TO AML AND CHRONIC PHASE (CP) PROGRESSION TO BLAST CRISIS (BC) IN CHRONIC MYELOID LEUKAEMIA (CML). EPIGENETIC STUDIES SHOWED THAT ID4 METHYLATION MIGHT BE ONE OF THE MECHANISMS SILENCING ID4 EXPRESSION IN MYELOID LEUKAEMIA. FUNCTIONAL STUDIES IN VITRO SHOWED THAT RESTORATION OF ID4 EXPRESSION COULD INHIBIT CELL PROLIFERATION AND PROMOTE APOPTOSIS IN BOTH K562 AND HL60 CELLS. THESE FINDINGS INDICATE THAT ID4 ACTS AS A TUMOUR SUPPRESSOR IN MYELOID MALIGNANCIES, AND ID4 METHYLATION IS A POTENTIAL BIOMARKER IN PREDICTING DISEASE PROGRESSION AND TREATMENT OUTCOME. 2017 4 2435 37 EPIGENETIC SILENCING OF SFRP1 ACTIVATES THE CANONICAL WNT PATHWAY AND CONTRIBUTES TO INCREASED CELL GROWTH AND PROLIFERATION IN HEPATOCELLULAR CARCINOMA. THE WNT PATHWAY IS A KEY REGULATOR OF EMBRYONIC DEVELOPMENT AND STEM CELLS, AND ITS ABERRANT ACTIVATION IS ASSOCIATED WITH HUMAN MALIGNANCIES, MOST NOTABLY HEPATOCELLULAR CARCINOMA (HCC). EPIGENETIC DEREGULATION OF THE GENES ENCODING THE SECRETED FRIZZLED-RELATED PROTEINS (SFRPS), THE WNT SIGNALLING ANTAGONISTS, HAS BEEN LINKED WITH ABERRANT HYPERACTIVATION OF THE WNT SIGNALLING IN HCC CELLS; HOWEVER, THE PRECISE UNDERLYING MECHANISM REMAINS ELUSIVE. WE INVESTIGATED THE METHYLATION PROFILES OF WNT ANTAGONISTS IN LIVER SAMPLES OF DIFFERENT STAGES OF HCC DEVELOPMENT AND LIVER CANCER CELL LINES AND STUDIED THE FUNCTIONAL IMPACT OF ABERRANT EPIGENETIC SILENCING OF SFRPS ON THE CANONICAL WNT PATHWAY AND CELL VIABILITY. WE FOUND THAT THE SFRP1 GENE ENCODING THE SUBUNIT IS A FREQUENT TARGET OF ABERRANT DNA HYPERMETHYLATION AND SILENCING IN HCC TUMOURS, WHEREAS OTHER EXTRACELLULAR WNT ANTAGONISTS, WIF1 AND DKK3, EXHIBITED NO METHYLATION IN TUMOUR CELLS, CONSISTENT WITH THE NOTION THAT ABERRANT METHYLATION EVENTS IN CANCER CELLS ARE NON-RANDOMLY DISTRIBUTED AMONG THE GENES AND THAT THERE IS A STRONG PREFERENCE FOR HYPERMETHYLATION OF SPECIFIC GENES IN HCC. IN ADDITION, BY COMPARING SFRP1 METHYLATION STATUS IN HCC TUMOURS WITH NORMAL, CIRRHOTIC AND CHRONIC HEPATITIS LIVER TISSUES, WE IDENTIFIED SFRP1 GENE AS A POTENTIAL EARLY MARKER OF HCC. THE RESTORATION OF SFRP1 EXPRESSION IN CANCER CELLS BY ECTOPIC EXPRESSION INHIBITED WNT ACTIVITY ACCOMPANIED WITH DESTABILIZATION OF BETA-CATENIN AND DOWNREGULATION OF C-MYC AND CYCLIN D1, THE KNOWN DOWNSTREAM TARGETS OF WNT PATHWAY. IMPORTANTLY, RESTORING SFRP1 LEVELS IN CANCER CELLS INHIBITED CELL GROWTH AND INDUCED APOPTOTIC CELL DEATH. THIS STUDY SUPPORTS THE CRITICAL ROLE FOR SFRP1 SILENCING IN HEPATOCELLULAR CARCINOMA AND REINFORCES THE IMPORTANCE OF THE WNT ANTAGONISTS IN PREVENTING ONCOGENIC STABILIZATION OF BETA-CATENIN AND CHRONIC ACTIVATION OF THE CANONICAL WNT PATHWAY, SUGGESTING THAT SFRP1 MAY BE AN ATTRACTIVE TARGET FOR EARLY CANCER DETECTION AND THERAPEUTIC INTERVENTION. 2012 5 1211 27 CPG ISLAND METHYLATION AND EXPRESSION OF THE SECRETED FRIZZLED-RELATED PROTEIN GENE FAMILY IN CHRONIC LYMPHOCYTIC LEUKEMIA. B-CELL CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) IS CHARACTERIZED BY A CLONAL ACCUMULATION OF MATURE NEOPLASTIC B CELLS INDICATING DISRUPTION OF APOPTOSIS. RESTRICTION LANDMARK GENOME SCANNING WAS DONE TO IDENTIFY NOVEL TARGET GENES SILENCED BY CPG ISLAND METHYLATION IN CLL. SECRETED FRIZZLED-RELATED PROTEIN 4 (SFRP4), A NEGATIVE REGULATOR OF THE WNT SIGNALING PATHWAY, WAS FOUND TO BE FREQUENTLY METHYLATED IN CLL SAMPLES. WNT SIGNALING HAS BEEN SHOWN TO CONTROL NORMAL APOPTOTIC BEHAVIOR AND IS REQUIRED FOR NORMAL B-CELL DEVELOPMENT WHEREAS ABERRANT ACTIVATION OF THIS PATHWAY HAS BEEN OBSERVED IN CLL. WE SHOW ABERRANT DNA METHYLATION AND SILENCING OF SFRP4, AS WELL AS OF ADDITIONAL SFRP FAMILY MEMBERS, IN PRIMARY CLL SAMPLES. INDUCTION OF THEIR EXPRESSION IN A DOSE-DEPENDENT MANNER FOLLOWING TREATMENT WITH A DEMETHYLATING AGENT, 5-AZA-2'-DEOXYCYTIDINE, WAS SHOWN. OF THE FIVE SFRP FAMILY MEMBERS STUDIED IN DETAIL, SFRP1 WAS HYPERMETHYLATED AND DOWN-REGULATED IN ALL CLL PATIENT SAMPLES STUDIED, SUGGESTING THAT THIS EPIGENETIC EVENT IS A CRITICAL STEP DURING LEUKEMOGENESIS. OUR RESULTS SUGGEST THAT SILENCING OF SFRPS BY CPG ISLAND METHYLATION IS ONE POSSIBLE MECHANISM CONTRIBUTING TO ABERRANT ACTIVATION OF WNT SIGNALING PATHWAY IN CLL. 2006 6 3444 27 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 7 2090 28 EPIGENETIC DYSREGULATION OF THE WNT SIGNALLING PATHWAY IN CHRONIC LYMPHOCYTIC LEUKAEMIA. BACKGROUND: WNT SIGNALLING HAS RECENTLY BEEN IMPLICATED IN THE PATHOGENESIS OF CANCER. METHODS: THIS STUDY INVESTIGATED THE ACTIVITY OF WNT SIGNALLING IN PERIPHERAL BLOOD CHRONIC LYMPHOCYTIC LEUKAEMIA (CLL) LYMPHOCYTES, AND THE METHYLATION STATUS OF SEVEN SOLUBLE WNT ANTAGONIST GENES, INCLUDING WIF1, DKK3, APC, SFRP1, SFRP2, SFRP4 AND SFRP5, BY USING METHYLATION-SPECIFIC PCR IN THE PERIPHERAL BLOOD CLL LYMPHOCYTES AND BONE MARROW SAMPLES OF PATIENTS WITH CLL AT DIAGNOSIS. RESULTS: IN THE PERIPHERAL BLOOD CLL LYMPHOCYTES, CONSTITUTIVE ACTIVATION OF WNT SIGNALLING WAS DETECTED, ASSOCIATED WITH HYPERMETHYLATION OF THE SOLUBLE WNT INHIBITOR GENES. IN THE DIAGNOSTIC CLL MARROW SAMPLES, METHYLATION OF THE SEVEN GENES WAS DETECTED IN UP TO 36.4% OF SAMPLES. MOREOVER, 23 (52.3%) PATIENTS HAD METHYLATION OF AT LEAST ONE OF THE SEVEN GENES, OF WHOM 14 (60.8%) HAD METHYLATION OF TWO OR MORE WNT INHIBITOR GENES. APART FROM AN ASSOCIATION OF ADVANCED AGE WITH DKK3 METHYLATION, THERE WAS NO ASSOCIATION OF GENE HYPERMETHYLATION WITH EITHER CLINICAL CHARACTERISTICS (INCLUDING AGE, GENDER, LYMPHOCYTE COUNT AT DIAGNOSIS, RAI STAGE AND POOR-RISK KARYOTYPE) OR SURVIVAL. CONCLUSION: WNT SIGNALLING IS CONSTITUTIVELY ACTIVATED IN CLL B LYMPHOCYTES IN ASSOCIATION WITH METHYLATION OF MULTIPLE SOLUBLE WNT ANTAGONIST GENES. METHYLATION OF THESE SOLUBLE WNT ANTAGONIST GENES, OCCASIONALLY MULTIPLE GENES, IN PRIMARY CLL MARROW SAMPLES SUGGESTS AN IMPORTANT ROLE IN CLL PATHOGENESIS. MOREOVER, THIS STUDY UNDERSCORED THE IMPORTANCE OF STUDYING METHYLATION OF A PANEL OF, BUT NOT INDIVIDUAL, GENES REGULATING A CELLULAR PATHWAY. 2008 8 2132 21 EPIGENETIC INACTIVATION OF THE MIR-124-1 IN HAEMATOLOGICAL MALIGNANCIES. MIR-124-1 IS A TUMOUR SUPPRESSOR MICRORNA (MIR). EPIGENETIC DEREGULATION OF MIRS IS IMPLICATED IN CARCINOGENESIS. PROMOTER DNA METHYLATION AND HISTONE MODIFICATION OF MIR-124-1 WAS STUDIED IN 5 NORMAL MARROW CONTROLS, 4 LYMPHOMA, 8 MULTIPLE MYELOMA (MM) CELL LINES, 230 DIAGNOSTIC PRIMARY SAMPLES OF ACUTE MYELOID LEUKAEMIA (AML), ACUTE LYMPHOBLASTIC LEUKAEMIA (ALL), CHRONIC MYELOID LEUKAEMIA (CML), CHRONIC LYMPHOCYTIC LEUKAEMIA (CLL), MM, AND NON-HODGKIN'S LYMPHOMA (NHL), AND 53 MM SAMPLES AT STABLE DISEASE OR RELAPSE. PROMOTER OF MIR-124-1 WAS UNMETHYLATED IN NORMAL CONTROLS BUT HOMOZYGOUSLY METHYLATED IN 4 OF 4 LYMPHOMA AND 4 OF 8 MYELOMA CELL LINES. TREATMENT OF 5-AZA-2'-DEOXYCYTIDINE LED TO MIR-124-1 DEMETHYLATION AND RE-EXPRESSION OF MATURE MIR-124, WHICH ALSO ASSOCIATED WITH EMERGENCE OF EUCHROMATIC TRIMETHYL H3K4 AND CONSEQUENT DOWNREGULATION OF CDK6 IN MYELOMA CELLS HARBORING HOMOZYGOUS MIR-124-1 METHYLATION. IN PRIMARY SAMPLES AT DIAGNOSIS, MIR-124-1 METHYLATION WAS ABSENT IN CML BUT DETECTED IN 2% EACH OF MM AT DIAGNOSIS AND RELAPSE/PROGRESSION, 5% ALL, 15% AML, 14% CLL AND 58.1% OF NHL (P<0.001). AMONGST LYMPHOID MALIGNANCIES, MIR-124-1 WAS PREFERENTIALLY METHYLATED IN NHL THAN MM, CLL OR ALL. IN PRIMARY LYMPHOMA SAMPLES, MIR-124-1 WAS PREFERENTIALLY HYPERMETHYLATED IN B- OR NK/T-CELL LYMPHOMAS AND ASSOCIATED WITH REDUCED MIR-124 EXPRESSION. IN CONCLUSION, MIR-124-1 WAS HYPERMETHYLATED IN A TUMOUR-SPECIFIC MANNER, WITH A HETEROCHROMATIC HISTONE CONFIGURATION. HYPOMETHYLATION LED TO PARTIAL RESTORATION OF EUCHROMATIC HISTONE CODE AND MIR RE-EXPRESSION. INFREQUENT MIR-124-1 METHYLATION DETECTED IN DIAGNOSTIC AND RELAPSE MM SAMPLES SHOWED AN UNIMPORTANT ROLE IN MM PATHOGENESIS, DESPITE FREQUENT METHYLATION FOUND IN CELL LINES. AMONGST HAEMATOLOGICAL CANCERS, MIR-124-1 WAS MORE FREQUENTLY HYPERMETHYLATED IN NHL, AND HENCE WARRANTS FURTHER STUDY. 2011 9 780 35 CELL-FREE DNA PROMOTER HYPERMETHYLATION IN PLASMA AS A DIAGNOSTIC MARKER FOR PANCREATIC ADENOCARCINOMA. BACKGROUND: PANCREATIC CANCER HAS A 5-YEAR SURVIVAL RATE OF ONLY 5-7%. DIFFICULTIES IN DETECTING PANCREATIC CANCER AT EARLY STAGES RESULTS IN THE HIGH MORTALITY AND SUBSTANTIATES THE NEED FOR ADDITIONAL DIAGNOSTIC TOOLS. SURGERY IS THE ONLY CURATIVE TREATMENT AND UNFORTUNATELY ONLY POSSIBLE IN LOCALIZED TUMOURS. A DIAGNOSTIC BIOMARKER FOR PANCREATIC CANCER WILL HAVE A MAJOR IMPACT ON PATIENT SURVIVAL BY FACILITATING EARLY DETECTION AND THE POSSIBILITY FOR CURATIVE TREATMENT. DNA PROMOTER HYPERMETHYLATION IS A MECHANISM OF EARLY CARCINOGENESIS, WHICH CAN CAUSE INACTIVATION OF TUMOUR SUPPRESSOR GENES. THE AIM OF THIS STUDY WAS TO EXAMINE PROMOTER HYPERMETHYLATION IN A PANEL OF SELECTED GENES FROM CELL-FREE DNA, AS A DIAGNOSTIC MARKER FOR PANCREATIC ADENOCARCINOMA. METHODS: PATIENTS WITH SUSPECTED OR BIOPSY-VERIFIED PANCREATIC CANCER WERE INCLUDED PROSPECTIVELY AND CONSECUTIVELY. PATIENTS WITH CHRONIC/ACUTE PANCREATITIS WERE INCLUDED AS ADDITIONAL BENIGN CONTROL GROUPS. BASED ON AN OPTIMIZED ACCELERATED BISULFITE TREATMENT PROTOCOL, METHYLATION-SPECIFIC PCR OF A 28 GENE PANEL WAS PERFORMED ON PLASMA SAMPLES. A DIAGNOSTIC PREDICTION MODEL WAS DEVELOPED BY MULTIVARIABLE LOGISTIC REGRESSION ANALYSIS USING BACKWARD STEPWISE ELIMINATION. RESULTS: PATIENTS WITH PANCREATIC ADENOCARCINOMA (N = 95), CHRONIC PANCREATITIS (N = 97) AND ACUTE PANCREATITIS (N = 59) AND PATIENTS SCREENED, BUT NEGATIVE FOR PANCREATIC ADENOCARCINOMA (N = 27), WERE INCLUDED. THE DIFFERENCE IN MEAN NUMBER OF METHYLATED GENES IN THE CANCER GROUP (8.41 (95% CI 7.62-9.20)) VS THE TOTAL CONTROL GROUP (4.74 (95% CI 4.40-5.08)) WAS HIGHLY SIGNIFICANT (P < 0.001). A DIAGNOSTIC PREDICTION MODEL (AGE >65, BMP3, RASSF1A, BNC1, MESTV2, TFPI2, APC, SFRP1 AND SFRP2) HAD AN AREA UNDER THE CURVE OF 0.86 (SENSITIVITY 76%, SPECIFICITY 83%). THE MODEL PERFORMANCE WAS INDEPENDENT OF CANCER STAGE. CONCLUSIONS: CELL-FREE DNA PROMOTER HYPERMETHYLATION HAS THE POTENTIAL TO BE A DIAGNOSTIC MARKER FOR PANCREATIC ADENOCARCINOMA AND DIFFERENTIATE BETWEEN MALIGNANT AND BENIGN PANCREATIC DISEASE. THIS STUDY BRINGS US CLOSER TO A CLINICAL USEFUL DIAGNOSTIC MARKER FOR PANCREATIC CANCER, WHICH IS URGENTLY NEEDED. EXTERNAL VALIDATION IS, HOWEVER, REQUIRED BEFORE THE TEST CAN BE APPLIED IN THE CLINIC. TRIAL REGISTRATION: CLINICALTRIALS.GOV, NCT02079363. 2016 10 507 42 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 11 3897 35 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 12 4903 19 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 13 2682 27 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 14 4904 32 P16INK4A GENE ALTERATIONS ARE NOT A PROGNOSTIC INDICATOR FOR SURVIVAL IN PATIENTS WITH HEPATOCELLULAR CARCINOMA UNDERGOING CURATIVE HEPATECTOMY. BACKGROUND AND AIM: HEPATOCELLULAR CARCINOMA (HCC) IS A COMMON MALIGNANCY WORLDWIDE THAT IS HIGHLY ASSOCIATED WITH CHRONIC HEPATITIS B OR C INFECTION AND CIRRHOSIS. THE TUMOR SUPPRESSOR GENE P16INK4A IS AN IMPORTANT COMPONENT OF THE CELL CYCLE AND INACTIVATION OF THE GENE HAS BEEN FOUND IN A VARIETY OF HUMAN CANCERS. THE PRESENT STUDY WAS PERFORMED TO DETERMINE GENETIC AND EPIGENETIC ALTERATIONS IN THE P16INK4A TUMOR SUPPRESSOR GENE AND THE EFFECT OF THESE ON HCC PROGRESSION. METHODS: THE STATUS OF P16INK4A WAS EVALUATED IN 117 HCC TUMORAL NODULES AND 110 CORRESPONDING PERITUMORAL TISSUES BY LOSS OF HETEROZIGOSITY (LOH) AT THE 9P21-22 REGION, HOMOZYGOUS DELETIONS, SINGLE-STRAND CONFORMATION POLYMORPHISM-POLYMERASE CHAIN REACTION (PCR) MUTATIONAL ANALYSIS AND METHYLATION SPECIFIC PCR. RESULTS: THE MOST FREQUENT INACTIVATION MECHANISM WAS HYPERMETHYLATION OF THE PROMOTER REGION, WHICH WAS FOUND IN 63.2% OF THE TUMOR SAMPLES AND IN 28.2% OF THE PERITUMORAL SAMPLES. LOSS OF HETEROZYGOSITY AT THE 9P21 REGION WAS DETECTED IN 27.3% AND 10% OF TUMOR AND PERITUMORAL TISSUES, RESPECTIVELY. HOMOZYGOUS DELETIONS AND MUTATIONS WERE LESS COMMON EVENTS IN HEPATOCARCINOGENESIS. THE AUTHORS FOUND 5.9% OF THE TUMOR CASES WITH EXON 2 HOMOZYGOUS DELETIONS AND 8.6% WITH MUTATIONS. TWO POLYMORPHISMS WERE DETECTED, ONE AT CODON 148 (GCG --> ACG, ALA --> THR) IN THREE CASES AND THE OTHER IN EXON 3 AT 540 BP (34.2% OF THE SAMPLES). NO ASSOCIATION WAS FOUND BETWEEN INACTIVATION OF P16INK4A AND CLINICOPATHOLOGICAL CHARACTERISTICS OR PROGNOSIS. CONCLUSION: P16INK4A IS ALTERED FREQUENTLY AND EARLY IN HCC, BEING THE PREDOMINANT MECHANISM OF INACTIVATION PROMOTER HYPERMETHYLATION. THE PRESENT RESULTS SUGGEST THAT THE P16INK4A GENE PLAYS AN IMPORTANT ROLE IN THE PATHOGENESIS OF HCC. 2004 15 1542 36 DNA METHYLATION IN HAEMATOLOGICAL MALIGNANCIES: THE ROLE OF DECITABINE. NORMAL CELL DEVELOPMENT AND FUNCTION IS DEPENDENT UPON CONTROLLED GENE EXPRESSION. DNA METHYLATION IS AN EPIGENETIC MODIFICATION THAT CAN PLAY AN IMPORTANT ROLE IN THE CONTROL OF GENE EXPRESSION. DNA METHYLATION AT CYTOSINE RESIDUES IN GENE PROMOTER CPG SEQUENCES IS KNOWN TO INHIBIT GENE TRANSCRIPTION. INAPPROPRIATE INHIBITION OF THE TRANSCRIPTION OF TUMOUR SUPPRESSOR GENES, GENES THAT INHIBIT ANGIOGENESIS AND METASTASIS AND GENES INVOLVED IN DNA REPAIR BY UNCONTROLLED METHYLATION, CAN LEAD TO UNREGULATED GROWTH AND PROLIFERATION OF A CELL AND CARCINOGENESIS. PROMOTER HYPERMETHYLATION AFFECTING THE P16 GENE, RESULTING IN GENE SILENCING, HAS BEEN SHOWN TO OCCUR IN MANY HUMAN SOLID TUMOURS AND A 'HYPERMETHYLATION PROFILE' IN SOME LEUKAEMIAS HAS BEEN DEFINED. THE MOLECULAR MECHANISMS BY WHICH ABERRANT DNA METHYLATION TAKES PLACE DURING CARCINOGENESIS ARE STILL NOT CLEAR. HOWEVER, THE LARGE NUMBER OF TARGET GENES (INVOLVED IN TUMORIGENESIS) THAT ARE SILENCED BY ABERRANT METHYLATION SUGGESTS THAT INHIBITION OF THIS PROCESS MAY HAVE POTENTIAL AS CANCER THERAPY. DECITABINE (NSC-127716, DACOGEN; SUPERGEN) IS A POTENT AND SPECIFIC HYPOMETHYLATING AGENT AND AN INHIBITOR OF THE DNA METHYLTRANSFERASE ACTIVITY THAT MEDIATES DNA METHYLATION. DECITABINE HAS BEEN SHOWN TO HAVE A BROAD RANGE OF ANTINEOPLASTIC ACTIVITY IN PRECLINICAL STUDIES. THIS AGENT HAS EXHIBITED SIGNIFICANT ACTIVITY IN THE TREATMENT OF PATIENTS WITH MYELODYSPLASTIC SYNDROME, CHRONIC MYELOID LEUKAEMIA AND ACUTE MYELOID LEUKAEMIA, ALTHOUGH CLINICAL PHASE I AND II STUDIES WITH SOLID TUMOURS HAVE NOT BEEN VERY PROMISING. PHASE II AND III STUDIES ARE CURRENTLY ONGOING TO EVALUATE DECITABINE, BOTH ALONE AND IN COMBINATION, IN VARIOUS STAGES OF THESE HAEMATOLOGICAL MALIGNANCIES. 2003 16 3098 24 GENOMIC DISRUPTION OF THE HISTONE METHYLTRANSFERASE SETD2 IN CHRONIC LYMPHOCYTIC LEUKAEMIA. HISTONE METHYLTRANSFERASES (HMTS) ARE IMPORTANT EPIGENETIC REGULATORS OF GENE TRANSCRIPTION AND ARE DISRUPTED AT THE GENOMIC LEVEL IN A SPECTRUM OF HUMAN TUMOURS INCLUDING HAEMATOLOGICAL MALIGNANCIES. USING HIGH-RESOLUTION SINGLE NUCLEOTIDE POLYMORPHISM (SNP) ARRAYS, WE IDENTIFIED RECURRENT DELETIONS OF THE SETD2 LOCUS IN 3% (8/261) OF CHRONIC LYMPHOCYTIC LEUKAEMIA (CLL) PATIENTS. FURTHER VALIDATION IN TWO INDEPENDENT COHORTS SHOWED THAT SETD2 DELETIONS WERE ASSOCIATED WITH LOSS OF TP53, GENOMIC COMPLEXITY AND CHROMOTHRIPSIS. WITH NEXT-GENERATION SEQUENCING WE DETECTED MUTATIONS OF SETD2 IN AN ADDITIONAL 3.8% OF PATIENTS (23/602). IN MOST CASES, SETD2 DELETIONS OR MUTATIONS WERE OFTEN OBSERVED AS A CLONAL EVENT AND ALWAYS AS A MONO-ALLELIC LESION, LEADING TO REDUCED MRNA EXPRESSION IN SETD2-DISRUPTED CASES. PATIENTS WITH SETD2 ABNORMALITIES AND WILD-TYPE TP53 AND ATM FROM FIVE CLINICAL TRIALS EMPLOYING CHEMOTHERAPY OR CHEMO-IMMUNOTHERAPY HAD REDUCED PROGRESSION-FREE AND OVERALL SURVIVAL COMPARED WITH CASES WILD TYPE FOR ALL THREE GENES. CONSISTENT WITH ITS POSTULATED ROLE AS A TUMOUR SUPPRESSOR, OUR DATA HIGHLIGHT SETD2 ABERRATION AS A RECURRENT, EARLY LOSS-OF-FUNCTION EVENT IN CLL PATHOBIOLOGY LINKED TO AGGRESSIVE DISEASE. 2016 17 1968 24 EPIGENETIC ALTERATION OF THE SOCS1 GENE IN CHRONIC MYELOID LEUKAEMIA. THE EXPRESSION OF THE SUPPRESSOR OF CYTOKINE SIGNALLING-1 (SOCS1) PROTEIN IS INDUCED IN RESPONSE TO STIMULATION BY SEVERAL CYTOKINES. THE INDUCED SOCS1 INHIBITS THE SIGNALLING PATHWAY THROUGH THE ASSOCIATION WITH A VARIETY OF TYROSINE KINASE PROTEINS. IN THIS STUDY, THE MUTATION ANALYSES, CPG ISLAND METHYLATION STATUS, AND THE EXPRESSION OF THE SOCS1 GENE IN 112 CHRONIC MYELOID LEUKAEMIA (CML) SAMPLES, FIVE LEUKAEMIA CELL LINES, AND 30 NORMAL CONTROLS WERE ANALYSED. NO GENETIC MUTATIONS OF SOCS1 GENE WERE NOTED IN THE CML SAMPLES. THE SOCS1 GENE WAS HYPERMETHYLATED IN 67% AND 46% OF THE BLASTIC AND CHRONIC PHASE CML SAMPLES RESPECTIVELY (P < 0.0001). HOWEVER, THERE WAS NO METHYLATION OF THE SOCS1 GENE IN NORMAL CONTROLS OR CML IN MOLECULAR REMISSION. THE METHYLATION STATUS OF THE SOCS1 GENE IS CONSISTENT WITH THE RESULTS OF THE REAL-TIME QUANTITATIVE REVERSE TRANSCRIPTION POLYMERASE CHAIN REACTION AND IMMUNOCYTOCHEMISTRY STAINING. OUR RESULTS DEMONSTRATE THAT THE SOCS1 GENE SILENCING IS CAUSED BY THE METHYLATION OF CPG ISLANDS IN CML AND IS REVERSED TO AN UNMETHYLATED STATUS IN MOLECULAR REMISSION. AS SOCS1 HAS UNIVERSAL ACTIVITY TO NEGATIVELY REGULATE SEVERAL CYTOKINE SIGNALLING PATHWAYS, THE LOSS OF THE NEGATIVE REGULATION OF CYTOKINE SIGNALLING BY THE SOCS1 MAY PLAY A ROLE IN THE PATHOGENESIS OF CML PROGRESSION. 2003 18 5969 27 TERT PROMOTER MUTATIONS IN PRIMARY LIVER TUMORS. NEXT-GENERATION SEQUENCING HAS DRAWN THE GENETIC LANDSCAPE OF HEPATOCELLULAR CARCINOMA AND SEVERAL SIGNALING PATHWAYS ARE ALTERED AT THE DNA LEVEL IN TUMORS: WNT/BETA-CATENIN, CELL CYCLE REGULATOR, EPIGENETIC MODIFIER, HISTONE METHYLTRANSFERASE, OXIDATIVE STRESS, RAS/RAF/MAP KINASE AND AKT/MTOR PATHWAYS. HEPATOCARCINOGENESIS IS A MULTISTEP PROCESS STARTING WITH THE EXPOSURE TO DIFFERENT RISK FACTORS, FOLLOWED BY THE DEVELOPMENT OF A CHRONIC LIVER DISEASE AND CIRRHOSIS PRECEDE IN THE VAST MAJORITY OF THE CASES THE DEVELOPMENT OF HCC. SEVERAL LINES OF EVIDENCE HAVE UNDERLINED THE PIVOTAL ROLE OF TELOMERE MAINTENANCE IN BOTH CIRRHOSIS AND HCC PATHOGENESIS. TERT PROMOTER MUTATIONS WERE IDENTIFIED AS THE MOST FREQUENT GENETIC ALTERATIONS IN HEPATOCELLULAR CARCINOMA WITH AN OVERALL FREQUENCY AROUND 60%. MOREOVER, IN CIRRHOSIS, TERT PROMOTER MUTATIONS ARE OBSERVED AT THE EARLY STEPS OF HEPATOCARCINOGENESIS SINCE THEY ARE RECURRENTLY IDENTIFIED IN LOW-GRADE AND HIGH-GRADE DYSPLASTIC NODULES. IN CONTRAST, ACQUISITION OF GENOMIC DIVERSITY THROUGH MUTATIONS OF CLASSICAL ONCOGENES AND TUMOR SUPPRESSOR GENES (TP53, CTNNB1, ARID1A...) OCCURRED ONLY IN PROGRESSED HCC. IN NORMAL LIVER, A SUBSET OF HCC CAN DERIVED FROM THE MALIGNANT TRANSFORMATION OF HEPATOCELLULAR ADENOMA (HCA). IN HCA, CTNNB1 MUTATIONS PREDISPOSE TO TRANSFORMATION OF HCA IN HCC AND TERT PROMOTER MUTATIONS ARE REQUIRED IN MOST OF THE CASES AS A SECOND HIT FOR A FULL MALIGNANT TRANSFORMATION. ALL THESE FINDINGS HAVE REFINED OUR KNOWLEDGE OF HCC PATHOGENESIS AND HAVE POINTED TELOMERASE AS A TARGET FOR TAILORED THERAPY IN THE FUTURE. 2016 19 5667 26 SFRP TUMOUR SUPPRESSOR GENES ARE POTENTIAL PLASMA-BASED EPIGENETIC BIOMARKERS FOR MALIGNANT PLEURAL MESOTHELIOMA. MALIGNANT PLEURAL MESOTHELIOMA (MPM) IS ASSOCIATED WITH ASBESTOS EXPOSURE. ASBESTOS CAN INDUCE CHRONIC INFLAMMATION WHICH IN TURN CAN LEAD TO SILENCING OF TUMOUR SUPPRESSOR GENES. WNT SIGNALING PATHWAY CAN BE AFFECTED BY CHRONIC INFLAMMATION AND IS ABERRANTLY ACTIVATED IN MANY CANCERS INCLUDING COLON AND MPM. SFRP GENES ARE ANTAGONISTS OF WNT PATHWAY, AND SFRPS ARE POTENTIAL TUMOUR SUPPRESSORS IN COLON, GASTRIC, BREAST, OVARIAN, AND LUNG CANCERS AND MESOTHELIOMA. THIS STUDY INVESTIGATED THE EXPRESSION AND DNA METHYLATION OF SFRP GENES IN MPM CELLS LINES WITH AND WITHOUT DEMETHYLATION TREATMENT. SIXTY-SIX PATIENT FFPE SAMPLES WERE ANALYSED AND HAVE SHOWED METHYLATION OF SFRP2 (56%) AND SFRP5 (70%) IN MPM. SFRP2 AND SFRP5 TUMOUR-SUPPRESSIVE ACTIVITY IN ELEVEN MPM LINES WAS CONFIRMED, AND LONG-TERM ASBESTOS EXPOSURE LED TO REDUCED EXPRESSION OF THE SFRP1 AND SFRP2 GENES IN THE MESOTHELIUM (MET-5A) VIA EPIGENETIC ALTERATIONS. FINALLY, DNA METHYLATION OF SFRPS IS DETECTABLE IN MPM PATIENT PLASMA SAMPLES, WITH METHYLATED SFRP2 AND SFRP5 SHOWING A TENDENCY TOWARDS GREATER ABUNDANCE IN PATIENTS. THESE DATA SUGGESTED THAT SFRP GENES HAVE TUMOUR-SUPPRESIVE ACTIVITY IN MPM AND THAT METHYLATED DNA FROM SFRP GENE PROMOTERS HAS THE POTENTIAL TO SERVE AS A BIOMARKER FOR MPM PATIENT PLASMA. 2017 20 2765 33 EXPRESSION, EPIGENETIC REGULATION, AND HUMORAL IMMUNOGENICITY OF CANCER-TESTIS ANTIGENS IN CHRONIC MYELOID LEUKEMIA. OBJECTIVE: CANCER-TESTIS (CT) ANTIGENS REPRESENT ATTRACTIVE TARGETS FOR TUMOR IMMUNOTHERAPY BASED ON THEIR TUMOR-RESTRICTED EXPRESSION AND IMMUNOGENICITY. HOWEVER, A BROAD PICTURE OF THE EXPRESSION OF CT ANTIGENS AND ASSOCIATED HUMORAL IMMUNE RESPONSES IN CHRONIC MYELOID LEUKEMIA (CML) IS STILL MISSING. METHODS: WE SCREENED CML CELL LINES AND BONE MARROW (BM) SAMPLES FROM HEALTHY DONORS BY RT-PCR FOR THE EXPRESSION OF 31 CT ANTIGENS BEFORE AND AFTER TREATMENT WITH EPIGENETIC AGENTS. EXPRESSION OF TUMOR-RESTRICTED ANTIGENS WAS FURTHER EXAMINED IN 60 CML PATIENTS AND HUMORAL IMMUNE RESPONSES AGAINST 15 CT ANTIGENS WERE SCREENED BY ELISA. RESULTS: IN UNTREATED CELL LINES WE DETECTED THE EXPRESSION OF 17 CT ANTIGENS THAT WERE ABSENT FROM NORMAL BM. EXPRESSION OF MOST ANTIGENS INCREASED FOLLOWING DEMETHYLATING TREATMENT WITH 5'-AZA-2'-DEOXYCYTIDINE. IN THESE SAMPLES, ONLY PRAME WAS REPEATEDLY DETECTED AND EXPRESSION CORRELATED WITH SEVERAL CLINICOPATHOLOGICAL PARAMETERS AND DECREASED OVERALL SURVIVAL. WE FURTHER SHOW THAT A LOWER FREQUENCY OF PRAME-POSITIVE SAMPLES DURING IMATINIB TREATMENT WAS NOT CAUSED BY GENE-SPECIFIC DOWNREGULATION. ANALYZING THE PATIENTS' ANTIBODY RESPONSES WE FOUND THAT THE VAST MAJORITY OF PATIENTS LACKED SPONTANEOUS IMMUNITY AGAINST CT ANTIGENS INCLUDING PRAME. CONCLUSIONS: CT ANTIGEN EXPRESSION CAN BE INCREASED BY THE APPLICATION OF EPIGENETIC AGENTS AND THE EXPRESSION OF PRAME CORRELATES WITH CLINICOPATHOLOGICAL PARAMETERS AND OVERALL SURVIVAL IN PATIENTS WITH CML, BUT DOES NOT LEAD TO HUMORAL IMMUNE RESPONSES. PRAME-SPECIFIC IMMUNOTHERAPY MIGHT REPRESENT A PROMISING APPROACH FOR THE ERADICATION OF RESIDUAL THERAPY-RESISTANT LEUKEMIC CELLS DUE TO ITS FREQUENT EXPRESSION AND STABILITY UNDER IMATINIB TREATMENT. 2010