1  6132 134 THE EPIGENETIC REGULATORS BMI1 AND RING1B ARE DIFFERENTIALLY REGULATED IN PANCREATITIS AND PANCREATIC DUCTAL ADENOCARCINOMA. CHRONIC PANCREATITIS AND PANCREATIC DUCTAL ADENOCARCINOMA (PDAC) ARE ASSOCIATED WITH MAJOR CHANGES IN CELL DIFFERENTIATION. THESE CHANGES MAY BE AT THE BASIS OF THE INCREASED RISK FOR PDAC AMONG PATIENTS WITH CHRONIC PANCREATITIS. POLYCOMB PROTEINS ARE EPIGENETIC SILENCERS EXPRESSED IN ADULT STEM CELLS; UP-REGULATION OF POLYCOMB PROTEINS HAS BEEN REPORTED TO OCCUR IN A VARIETY OF SOLID TUMOURS SUCH AS COLON AND BREAST CANCER. WE HYPOTHESIZED THAT POLYCOMB MIGHT PLAY A ROLE IN PRENEOPLASTIC STATES IN THE PANCREAS AND IN TUMOUR DEVELOPMENT/PROGRESSION. TO TEST THESE IDEAS, WE DETERMINED THE EXPRESSION OF PRC1 COMPLEX PROTEINS (BMI1 AND RING1B) DURING PANCREATIC DEVELOPMENT AND IN PANCREATIC TISSUE FROM MOUSE MODELS OF DISEASE: ACUTE AND CHRONIC PANCREATIC INJURY, DUCT LIGATION, AND IN K-RAS(G12V) CONDITIONAL KNOCK-IN AND CAERULEIN-TREATED K-RAS(G12V) MICE. THE STUDY WAS EXTENDED TO HUMAN PANCREATIC TISSUE SAMPLES. TO OBTAIN MECHANISTIC INSIGHTS, BMI1 EXPRESSION IN CELLS UNDERGOING IN VITRO EXOCRINE CELL METAPLASIA AND THE EFFECTS OF BMI1 DEPLETION IN AN ACINAR CANCER CELL LINE WERE STUDIED. WE FOUND THAT BMI1 AND RING1B ARE EXPRESSED IN PANCREATIC EXOCRINE PRECURSOR CELLS DURING EARLY DEVELOPMENT AND IN DUCTAL AND ISLET CELLS-BUT NOT ACINAR CELLS-IN THE ADULT PANCREAS. BMI1 EXPRESSION WAS INDUCED IN ACINAR CELLS DURING ACUTE INJURY, IN ACINAR-DUCTAL METAPLASTIC LESIONS, AS WELL AS IN PANCREATIC INTRAEPITHELIAL NEOPLASIA (PANIN) AND PDAC. IN CONTRAST, RING1B EXPRESSION WAS ONLY SIGNIFICANTLY AND PERSISTENTLY UP-REGULATED IN HIGH-GRADE PANINS AND IN PDAC. BMI1 KNOCKDOWN IN CULTURED ACINAR TUMOUR CELLS LED TO CHANGES IN THE EXPRESSION OF VARIOUS DIGESTIVE ENZYMES. OUR RESULTS SUGGEST THAT BMI1 AND RING1B ARE MODULATED IN PANCREATIC DISEASES AND COULD CONTRIBUTE DIFFERENTLY TO TUMOUR DEVELOPMENT.	2009	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              
2  1742  40 EARLY EPIGENETIC DOWNREGULATION OF WNK2 KINASE DURING PANCREATIC DUCTAL ADENOCARCINOMA DEVELOPMENT. PANCREATIC DUCTAL ADENOCARCINOMA (PDAC) IS USUALLY INCURABLE. CONTRARY TO GENETIC MECHANISMS INVOLVED IN PDAC PATHOGENESIS, EPIGENETIC ALTERATIONS ARE ILL DEFINED. HERE, WE DETERMINE THE CONTRIBUTION OF EPIGENETICALLY SILENCED GENES TO THE DEVELOPMENT OF PDAC. WE ANALYZED ENRICHED, HIGHLY METHYLATED DNAS FROM PDACS, CHRONIC PANCREATITIS (CP) AND NORMAL TISSUES USING CPG ISLAND MICROARRAYS AND IDENTIFIED WNK2 AS A PROMINENT CANDIDATE TUMOR SUPPRESSOR GENE BEING DOWNREGULATED EARLY IN PDAC DEVELOPMENT. WNK2 WAS FURTHER INVESTIGATED IN TISSUE MICROARRAYS, METHYLATION ANALYSIS OF EARLY PANCREATIC INTRAEPITHELIAL NEOPLASIA (PANIN), MOUSE MODELS FOR PDAC AND PANCREATITIS, RE-EXPRESSION STUDIES AFTER DEMETHYLATION, AND CELL GROWTH ASSAYS USING WNK2 OVEREXPRESSION. DEMETHYLATION ASSAYS CONFIRMED THE LINK BETWEEN METHYLATION AND EXPRESSION. WNK2 HYPERMETHYLATION WAS HIGHER IN TUMOR THAN IN SURROUNDING INFLAMED TISSUES AND WAS OBSERVED IN PANIN LESIONS AS WELL AS IN A PDAC MOUSE MODEL. WNK2 MRNA AND PROTEIN EXPRESSIONS WERE LOWER IN PDAC AND CP COMPARED WITH NORMAL TISSUES BOTH IN PATIENTS AND MOUSE MODELS. OVEREXPRESSION OF WNK2 LED TO REDUCED CELL GROWTH, AND WNK2 EXPRESSION IN TISSUES CORRELATED NEGATIVELY WITH PERK1/2 EXPRESSION, A DOWNSTREAM TARGET OF WNK2 RESPONSIBLE FOR CELL PROLIFERATION. DOWNREGULATION OF WNK2 BY PROMOTER HYPERMETHYLATION OCCURS EARLY IN PDAC PATHOGENESIS AND MAY SUPPORT TUMOR CELL GROWTH VIA THE ERK-MAPK PATHWAY.	2014	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       
3  6596  40 TUMOR-SUPPRESSIVE MIR-192-5P HAS PROGNOSTIC VALUE IN PANCREATIC DUCTAL ADENOCARCINOMA. PANCREATIC DUCTAL ADENOCARCINOMA (PDAC) IS CHARACTERIZED BY FAST TUMOR PROGRESSION AND DIAGNOSIS AT ADVANCED, INOPERABLE STAGES. PREVIOUS STUDIES COULD DEMONSTRATE AN INVOLVEMENT OF MIR-192-5P IN EPIGENETIC REGULATION OF VISCERAL CARCINOMAS. DUE TO CONTRADICTORY RESULTS, HOWEVER, THE CLINICAL UTILITY OF MIR-192-5P IN PDAC HAS YET TO BE DETERMINED. MIR-192-5P EXPRESSION WAS ANALYZED BY RT-QRT-PCR IN HUMAN PDAC AND BENIGN TISSUE (N = 78), BLOOD SERUM (N = 81) AND SERUM EXOSOMES (N = 74), AS WELL AS IN PDAC CELL LINES (N = 5), CHEMORESISTANT CELL CLONES (N = 2), AND PANCREATIC DUCT CELL LINE H6C7. ANALYSIS OF EMT-ASSOCIATED (EPITHELIAL-TO-MESENCHYMAL TRANSITION) PROTEINS WAS PERFORMED BY IMMUNOHISTOCHEMISTRY AND WESTERN BLOT. MIR-192-5P WAS DEREGULATED IN PDAC AS COMPARED TO HEALTHY CONTROLS (HCS), WITH DOWNREGULATION IN MACRODISSECTED TISSUE (P < 0.001) AND UPREGULATION IN BLOOD SERUM OF PDAC UICC (UNION FOR INTERNATIONAL CANCER CONTROL) STAGE IV (P = 0.016) AND SERUM EXOSOMES OF PDAC UICC STAGES II TO IV (P < 0.001). MIR-192-5P EXPRESSION IN TUMOR TISSUE WAS SIGNIFICANTLY LOWER AS COMPARED TO CORRESPONDING PERITUMORAL TISSUE (PDAC UICC STAGE II: P < 0.001; PDAC UICC STAGE III: P = 0.024), WHILE EMT MARKERS ZEB1 AND ZEB2 WERE MORE FREQUENTLY EXPRESSED IN TUMOR TISSUE AS COMPARED TO PERITUMORAL TISSUE, HCS, AND CHRONIC PANCREATITIS. TISSUE-DERIVED (AUC OF 0.86; P < 0.0001) AND EXOSOMAL (AUC OF 0.83; P = 0.0004) MIR-192-5P COULD DIFFERENTIATE BETWEEN PDAC AND HCS WITH GOOD ACCURACY. FURTHERMORE, HIGH EXPRESSION OF MIR-192-5P IN PDAC TISSUE OF CURATIVELY RESECTED PDAC PATIENTS CORRELATED WITH PROLONGED OVERALL AND RECURRENCE-FREE SURVIVAL IN MULTIVARIATE ANALYSIS. IN VITRO, MIR-192-5P WAS DOWNREGULATED IN GEMCITABINE-RESISTANT CELL CLONES OF ASPC-1 (P = 0.029). TRANSIENT TRANSFECTION OF MIA PACA-2 CELLS WITH MIR-192-5P MIMIC RESULTED IN DOWNREGULATION OF ZEB2. MIR-192-5P SEEMS TO POSSESS A TUMOR-SUPPRESSIVE ROLE AND HIGH POTENTIAL AS A DIAGNOSTIC AND PROGNOSTIC MARKER IN PDAC.	2020	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           
4  1741  44 EARLY EPIGENETIC DOWNREGULATION OF MICRORNA-192 EXPRESSION PROMOTES PANCREATIC CANCER PROGRESSION. PANCREATIC DUCTAL ADENOCARCINOMA (PDAC) IS CHARACTERIZED BY VERY EARLY METASTASIS, SUGGESTING THE HYPOTHESIS THAT METASTASIS-ASSOCIATED CHANGES MAY OCCUR PRIOR TO ACTUAL TUMOR FORMATION. IN THIS STUDY, WE IDENTIFIED MIR-192 AS AN EPIGENETICALLY REGULATED SUPPRESSOR GENE WITH PREDICTIVE VALUE IN THIS DISEASE. MIR-192 WAS DOWNREGULATED BY PROMOTER METHYLATION IN BOTH PDAC AND CHRONIC PANCREATITIS, THE LATTER OF WHICH IS A MAJOR RISK FACTOR FOR THE DEVELOPMENT OF PDAC. FUNCTIONAL STUDIES IN VITRO AND IN VIVO IN MOUSE MODELS OF PDAC SHOWED THAT OVEREXPRESSION OF MIR-192 WAS SUFFICIENT TO REDUCE CELL PROLIFERATION AND INVASION. MECHANISTIC ANALYSES CORRELATED CHANGES IN MIR-192 PROMOTER METHYLATION AND EXPRESSION WITH EPITHELIAL-MESENCHYMAL TRANSITION. CELL PROLIFERATION AND INVASION WERE LINKED TO ALTERED EXPRESSION OF THE MIR-192 TARGET GENE SERPINE1 THAT IS ENCODING THE PROTEIN PLASMINOGEN ACTIVATOR INHIBITOR-1 (PAI-1), AN ESTABLISHED REGULATOR OF THESE PROPERTIES IN PDAC CELLS. NOTABLY, OUR DATA SUGGESTED THAT INVASIVE CAPACITY WAS ALTERED EVEN BEFORE NEOPLASTIC TRANSFORMATION OCCURRED, AS TRIGGERED BY MIR-192 DOWNREGULATION. OVERALL, OUR RESULTS HIGHLIGHTED A ROLE FOR MIR-192 IN EXPLAINING THE EARLY METASTATIC BEHAVIOR OF PDAC AND SUGGESTED ITS RELEVANCE AS A TARGET TO DEVELOP FOR EARLY DIAGNOSTICS AND THERAPY. CANCER RES; 76(14); 4149-59. (C)2016 AACR.	2016	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      
5  4334  23 MICRORNAS: NOVEL DIAGNOSTIC AND THERAPEUTIC TOOLS FOR PANCREATIC DUCTAL ADENOCARCINOMA? PANCREATIC DUCTAL ADENOCARCINOMA (PDAC) IS KNOWN FOR ITS VERY POOR OVERALL PROGNOSIS, MAKING TOOLS FOR EARLY DIAGNOSIS AND NEW THERAPEUTIC MODALITIES URGENTLY NEEDED. MICRORNAS (MIRNAS), ENDOGENOUS NONCODING RNA MOLECULES OF APPROXIMATELY 22 NT, HAVE GAINED ATTENTION AS AN EPIGENETIC COMPONENT INVOLVED IN THE DEVELOPMENT OF MANY CANCERS, INCLUDING PDAC. MIRNA EXPRESSION PROFILES OF VARYING PANCREATIC TISSUES HAVE IDENTIFIED A NUMBER OF DIFFERENTIALLY EXPRESSED MIRNAS AND SEEM TO BE ABLE TO DIFFERENTIATE BETWEEN THREE TISSUES OF CLINICAL IMPORTANCE: NORMAL PANCREAS, CHRONIC PANCREATITIS, AND PDAC. THIS ARTICLE GATHERS OUR CURRENT KNOWLEDGE OF DIFFERENTIALLY EXPRESSED MIRNAS IN PANCREATIC TISSUES WITH RELEVANCE TO PDAC AND PRESENTS POTENTIAL DIAGNOSTIC AND THERAPEUTIC OPPORTUNITIES.	2009	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         
6  1435  44 DIFFERENTIAL METHYLATION LANDSCAPE OF PANCREATIC DUCTAL ADENOCARCINOMA AND ITS PRECANCEROUS LESIONS. BACKGROUND: PANCREATIC CANCER IS ONE OF THE MOST LETHAL DISEASES WITH AN INCIDENCE ALMOST EQUAL TO THE MORTALITY. IN ADDITION TO HAVING GENETIC CAUSES, CANCER CAN ALSO BE CONSIDERED AN EPIGENETIC DISEASE. DNA METHYLATION IS THE PREMIER EPIGENETIC MODIFICATION AND PATTERNS OF ABERRANT DNA METHYLATION ARE RECOGNIZED TO BE A COMMON HALLMARK OF HUMAN TUMOR. IN THE MULTISTAGE CARCINOGENESIS OF PANCREAS STARTING FROM PRECANCEROUS LESIONS TO PANCREATIC DUCTAL ADENOCARCINOMA (PDAC), THE EPIGENETIC CHANGES PLAY A SIGNIFICANT ROLE. DATA SOURCES: RELEVANT STUDIES FOR THIS REVIEW WERE DERIVED VIA AN EXTENSIVE LITERATURE SEARCH IN PUBMED VIA USING VARIOUS KEYWORDS SUCH AS PANCREATIC DUCTAL ADENOCARCINOMA, PRECANCEROUS LESIONS, METHYLATION PROFILE, EPIGENETIC BIOMARKERS THAT ARE RELEVANT DIRECTLY OR CLOSELY ASSOCIATED WITH THE CONCERNED AREA OF OUR INTEREST. THE LITERATURE SEARCH WAS INTENSIVELY DONE CONSIDERING A TIME FRAME OF 20 YEARS (1998-2018). RESULT: IN THIS REVIEW WE HAVE HIGHLIGHTED THE HYPERMETHYLATION AND HYPOMETHYLATION OF THE PRECANCEROUS PDAC LESIONS (PANCREATIC INTRA-EPITHELIAL NEOPLASIA, INTRADUCTAL PAPILLARY MUCINOUS NEOPLASM, MUCINOUS CYSTIC NEOPLASM AND CHRONIC PANCREATITIS) AND PDAC ALONG WITH THE POTENTIAL BIOMARKERS. WE HAVE ALSO ACHIEVED THE EARLY EPIGENETIC DRIVER THAT LEADS TO PROGRESSION FROM PRECANCEROUS LESIONS TO PDAC. A BUNCH OF EPIGENETIC DRIVER GENES LEADS TO PROGRESSION OF PRECANCEROUS LESIONS TO PDAC (PPENK, APC, P14/5/16/17, HMLH1 AND MGMT) ARE ALSO DOCUMENTED. WE SUMMARIZED THE IMPORTANCE OF THESE OBSERVATIONS IN THERAPEUTICS AND DIAGNOSIS OF PDAC HENCE IDENTIFYING THE POTENTIAL USE OF EPIGENETIC BIOMARKERS IN EPIGENETIC TARGETED THERAPY. EPIGENETIC INACTIVATION OCCURS BY HYPERMETHYLATION OF CPG ISLANDS IN THE PROMOTER REGIONS OF TUMOR SUPPRESSOR GENES. WE LISTED ALL HYPER- AND HYPOMETHYLATION OF CPG ISLANDS OF SEVERAL GENES IN PDAC INCLUDING ITS PRECANCEROUS LESIONS. CONCLUSIONS: THE CONCEPT OF THE REVIEW WOULD HELP TO UNDERSTAND THEIR BIOLOGICAL EFFECTS, AND TO DETERMINE WHETHER THEY MAY BE SUCCESSFULLY COMBINED WITH OTHER EPIGENETIC DRUGS. HOWEVER, WE NEED TO CONTINUE OUR RESEARCH TO DEVELOP MORE SPECIFIC DNA-DEMETHYLATING AGENTS, WHICH ARE THE TARGETS FOR HYPERMETHYLATED CPG METHYLATION SITES.	2020	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
7   779  27 CELL-FREE DNA PROMOTER HYPERMETHYLATION AS A DIAGNOSTIC MARKER FOR PANCREATIC DUCTAL ADENOCARCINOMA - AN EXTERNAL VALIDATION STUDY. BACKGROUND: WE RECENTLY IDENTIFIED A DIAGNOSTIC PREDICTION MODEL BASED ON PROMOTER HYPERMETHYLATION OF EIGHT SELECTED GENES IN PLASMA CELL-FREE (CF) DNA, WHICH SHOWED PROMISING RESULTS AS A DIAGNOSTIC BIOMARKER FOR PANCREATIC DUCTAL ADENOCARCINOMA (PDAC). THE AIM OF THE PRESENT STUDY WAS TO VALIDATE THIS BIOMARKER PROFILE IN AN EXTERNAL PATIENT COHORT AND EXAMINE ANY ADDITIONAL EFFECT OF SERUM CA 19-9. METHODS: PATIENTS WITH PDAC (N = 346, STAGE I-IV) AND CHRONIC PANCREATITIS (N = 25) WERE INCLUDED. METHYLATION-SPECIFIC PCR OF A 28-GENE PANEL WAS PERFORMED ON SERUM CFDNA SAMPLES. THE PREVIOUSLY DEVELOPED DIAGNOSTIC PREDICTION MODEL (AGE>65 YEARS, BMP3, RASSF1A, BNC1, MESTV2, TFPI2, APC, SFRP1 AND SFRP2) WAS VALIDATED ALONE AND IN COMBINATION WITH SERUM CA 19-9 IN THIS EXTERNAL PATIENT COHORT. RESULTS: PATIENTS WITH PDAC HAD A HIGHER NUMBER OF HYPERMETHYLATED GENES (MEAN 8.11, 95% CI 7.70-8.52) THAN PATIENTS WITH CHRONIC PANCREATITIS (MEAN 5.60, 95% CI 4.42-6.78, P = 0.011). VALIDATION OF THE DIAGNOSTIC PREDICTION MODEL YIELDED AN AUC OF 0.77 (95% CI 0.69-0.84). THE COMBINATION OF SERUM CA 19-9 AND OUR TEST HAD AN AUC OF 0.93 (95% CI 0.89-0.96) IN THE PRIMARY STUDY AND 0.85 (95% CI 0.79-0.91) IN THE VALIDATION STUDY. CONCLUSION: IN THIS VALIDATION STUDY, PDAC WAS ASSOCIATED WITH A HIGHER NUMBER OF HYPERMETHYLATED GENES IN SERUM CFDNA THAN CHRONIC PANCREATITIS. OUR DIAGNOSTIC TEST WAS SUPERIOR TO THE PREDICTIVE VALUE OF SERUM CA 19-9 ALONE IN BOTH THE PRIMARY AND THE VALIDATION STUDY. THE COMBINATION OF OUR TEST WITH CA 19-9 MAY SERVE AS A CLINICALLY USEFUL DIAGNOSTIC BIOMARKER FOR PDAC.	2021	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        
8  6539  35 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	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              
9  6028  26 THE BMI1 POLYCOMB PROTEIN REPRESSES CYCLIN G2-INDUCED AUTOPHAGY TO SUPPORT PROLIFERATION IN CHRONIC MYELOID LEUKEMIA CELLS. THE BMI1 POLYCOMB PROTEIN REGULATES SELF-RENEWAL, PROLIFERATION AND SURVIVAL OF CANCER-INITIATING CELLS ESSENTIALLY THROUGH EPIGENETIC REPRESSION OF THE CDKN2A TUMOR SUPPRESSOR LOCUS. WE DEMONSTRATE HERE FOR THE FIRST TIME THAT BMI1 ALSO PREVENTS AUTOPHAGY IN CHRONIC MYELOID LEUKEMIA (CML) CELL LINES, TO SUPPORT THEIR PROLIFERATION AND CLONOGENIC ACTIVITY. USING CHROMATIN IMMUNOPRECIPITATION, WE IDENTIFIED CCNG2/CYCLIN G2 (CCNG2) AS A DIRECT BMI1 TARGET. BMI1 DOWNREGULATION IN CD34+ CML CELLS BY PTC-209 PHARMACOLOGICAL TREATMENT OR SHBMI1 TRANSDUCTION TRIGGERED CCNG2 EXPRESSION AND DECREASED CLONOGENIC ACTIVITY. ALSO, ECTOPIC EXPRESSION OF CCNG2 IN CD34+ CML CELLS STRONGLY DECREASED THEIR CLONOGENICITY. CCNG2 WAS SHOWN TO ACT BY DISRUPTING THE PHOSPHATASE 2A COMPLEX, WHICH ACTIVATES A PKCZETA-AMPK-JNK-ERK PATHWAY THAT ENGAGES AUTOPHAGY. WE OBSERVED THAT BMI1 AND CCNG2 LEVELS EVOLVED INVERSELY DURING THE PROGRESSION OF CML TOWARDS AN ACUTE DEADLY PHASE, AND THEREFORE HYPOTHESIZED THAT BMI1 COULD SUPPORT ACUTE TRANSFORMATION OF CML THROUGH THE SILENCING OF A CCNG2-MEDIATED TUMOR-SUPPRESSIVE AUTOPHAGY RESPONSE.	2015	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       
10   507  44 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  1064  43 CLINICAL SIGNIFICANCE OF PROMOTER METHYLATION STATUS OF TUMOR SUPPRESSOR GENES IN CIRCULATING DNA OF PANCREATIC CANCER PATIENTS. INTRODUCTION: PANCREATIC DUCTAL ADENOCARCINOMA (PDAC) IS A VERY AGGRESSIVE CANCER. THERE ARE VARIOUS SUB-CELLULAR EVENTS (BOTH GENETIC AND EPIGENETIC) THAT GET DYSREGULATED LEADING TO TUMORIGENESIS. METHYLATION IN PROMOTERS OF TUMOR SUPPRESSOR GENES IS ONE OF THESE EPIGENETIC PHENOMENA CONTRIBUTING TO THE PATHOGENESIS OF CANCER. GENES ANALYZED FOR PROMOTER METHYLATION STATUS IN THIS STUDY NAMELY SPARC (SECRETED PROTEIN ACIDIC AND RICH IN CYSTEINE, UCHL1 (UBIQUITIN CARBOXY-TERMINAL HYDROLASE L1), NPTX2 (NEURONAL PENTRAXIN 2), PENK (PROENKEPHALIN) HAD BEEN STUDIED IN PANCREATIC CANCER, BUT THERE IS A NEED TO CHECK METHYLATION IN THESE GENES AS CIRCULATORY NON-INVASIVE MARKERS. THIS STUDY ANALYZED THE ABSOLUTE QUANTIFICATION OF METHYLATION LEVELS OF SPARC, UCHL1, PENK, AND NPTX2 GENES PROMOTERS IN PDAC PATIENTS AS WELL AS IN CHRONIC PANCREATITIS (CP) PATIENTS AND HEALTHY SUBJECTS (HC) AND EVALUATED ITS CLINICAL SIGNIFICANCE IN PDAC. MATERIALS AND METHODS: THE STUDY INCLUDED 65 PDAC PATIENTS, 25 CP PATIENTS, AND 25 HEALTHY CONTROLS. DNA WAS EXTRACTED FROM THEIR PLASMA SAMPLES AND SUBSEQUENTLY GIVEN BISULFITE TREATMENT. ABSOLUTE QUANTIZATION OF METHYLATED AND UNMETHYLATED COPIES OF GENE PROMOTERS OF ALL THE FOUR GENES WAS PERFORMED USING REAL-TIME PCR (SYBR GREEN) BY THE STANDARD CURVE METHOD. METHYLATION LEVELS WERE EXPRESSED AS METHYLATION INDEX (MI) FOR EACH GENE IN EACH PATIENT. MI WAS CALCULATED FROM ABSOLUTE COPY NUMBERS AS FOLLOWS: MI-METHYLATED COPY NUMBER/METHYLATED COPY NUMBER + UNMETHYLATED COPY NUMBER). THESE INDICES WERE USED TO COMPARE GENE METHYLATION LEVELS WITHIN DIFFERENT GROUPS AND TO CORRELATE WITH CLINICOPATHOLOGICAL FEATURES AND SURVIVAL OF PANCREATIC CANCER PATIENTS. AN APPROPRIATE STATISTICAL ANALYSIS WAS APPLIED. RESULTS: METHYLATION INDICES FOR ALL THE FOUR GENES IN PDAC CASES WERE FOUND TO BE SIGNIFICANTLY HIGHER AS COMPARED TO THAT IN HEALTHY INDIVIDUALS. SPARC MI VALUES WERE FOUND TO DIFFERENTIATE EARLY-STAGE PDAC PATIENTS FROM CP PATIENTS. PDAC PATIENTS WITH THE METASTASIZED DISEASE AND STAGE IV DISEASE WERE FOUND TO HAVE HIGH MI FOR THE SPARC GENE AS WELL AS FOR THE NPTX2 GENE, WHILE A HIGHER UCHL1 METHYLATION INDEX WAS FOUND TO CORRELATE WITH AN ADVANCED STAGE OF THE DISEASE. HIGHER MI VALUES FOR SPARC AND NPTX2 GENES WERE FOUND TO ASSOCIATE WITH POOR SURVIVAL IN PATIENTS WITH PDAC. CONCLUSION: METHYLATION LOAD IN THE FORM OF MI FOR EACH OF THE FOUR GENES ASSESSED IN PLASMA MAY EMERGE AS A NON-INVASIVE BIOMARKER TO DIFFERENTIATE PANCREATIC CANCER FROM HEALTHY INDIVIDUALS. BUT ONLY SPARC AND NPTX2 HYPERMETHYLATION WERE ABLE TO DISTINGUISH PANCREATIC CANCER FROM CHRONIC PANCREATITIS. ASSOCIATION OF ABERRANT METHYLATION IN SPARC AND NPTX2 GENE WITH METASTASIS AND POOR SURVIVAL OF PATIENTS SUGGEST THE ROLE OF METHYLATION IN THESE GENES AS PROGNOSTIC MARKERS.	2020	
                       
12  1158  49 CONTEXT-DEPENDENT EPIGENETIC REGULATION OF NUCLEAR FACTOR OF ACTIVATED T CELLS 1 IN PANCREATIC PLASTICITY. BACKGROUND & AIMS: THE ABILITY OF EXOCRINE PANCREATIC CELLS TO CHANGE THE CELLULAR PHENOTYPE IS REQUIRED FOR TISSUE REGENERATION UPON INJURY, BUT ALSO CONTRIBUTES TO THEIR MALIGNANT TRANSFORMATION AND TUMOR PROGRESSION. WE INVESTIGATED CONTEXT-DEPENDENT SIGNALING AND TRANSCRIPTION MECHANISMS THAT DETERMINE PANCREATIC CELL FATE DECISIONS TOWARD REGENERATION AND MALIGNANCY. IN PARTICULAR, WE STUDIED THE FUNCTION AND REGULATION OF THE INFLAMMATORY TRANSCRIPTION FACTOR NUCLEAR FACTOR OF ACTIVATED T CELLS 1 (NFATC1) IN PANCREATIC CELL PLASTICITY AND TISSUE ADAPTATION. METHODS: WE ANALYZED CELL PLASTICITY DURING PANCREATIC REGENERATION AND TRANSFORMATION IN MICE WITH PANCREAS-SPECIFIC EXPRESSION OF A CONSTITUTIVELY ACTIVE FORM OF NFATC1, OR DEPLETION OF ENHANCER OF ZESTE 2 HOMOLOGUE 2 (EZH2), IN THE CONTEXT OF WILD-TYPE OR CONSTITUTIVELY ACTIVATE KRAS, RESPECTIVELY. ACUTE AND CHRONIC PANCREATITIS WERE INDUCED BY INTRAPERITONEAL INJECTION OF CAERULEIN. EZH2-DEPENDENT REGULATION OF NFATC1 EXPRESSION WAS STUDIED IN MOUSE IN HUMAN PANCREATIC TISSUE AND CELLS BY IMMUNOHISTOCHEMISTRY, IMMUNOBLOTTING, AND QUANTITATIVE REVERSE TRANSCRIPTION POLYMERASE CHAIN REACTION. WE USED GENETIC AND PHARMACOLOGIC APPROACHES OF EZH2 AND NFATC1 INHIBITION TO STUDY THE CONSEQUENCES OF PATHWAY DISRUPTION ON PANCREATIC MORPHOLOGY AND FUNCTION. EPIGENETIC MODIFICATIONS ON THE NFATC1 GENE WERE INVESTIGATED BY CHROMATIN IMMUNOPRECIPITATION ASSAYS. RESULTS: NFATC1 WAS RAPIDLY AND TRANSIENTLY INDUCED IN EARLY ADAPTATION TO ACINAR CELL INJURY IN HUMAN SAMPLES AND IN MICE, WHERE IT PROMOTED ACINAR CELL TRANSDIFFERENTIATION AND BLOCKED PROLIFERATION OF METAPLASTIC PANCREATIC CELLS. HOWEVER, IN LATE STAGES OF REGENERATION, NFATC1 WAS EPIGENETICALLY SILENCED BY EZH2-DEPENDENT HISTONE METHYLATION, TO ENABLE ACINAR CELL REDIFFERENTIATION AND PREVENT ORGAN ATROPHY AND EXOCRINE INSUFFICIENCY. IN CONTRAST, ONCOGENIC ACTIVATION OF KRAS SIGNALING IN PANCREATIC DUCTAL ADENOCARCINOMA CELLS REVERSED THE EZH2-DEPENDENT EFFECTS ON THE NFATC1 GENE AND WAS REQUIRED FOR EZH2-MEDIATED TRANSCRIPTIONAL ACTIVATION OF NFATC1. CONCLUSIONS: IN STUDIES OF HUMAN AND MOUSE PANCREATIC CELLS AND TISSUE, WE IDENTIFIED CONTEXT-SPECIFIC EPIGENETIC REGULATION OF NFATC1 ACTIVITY AS AN IMPORTANT MECHANISM OF PANCREATIC CELL PLASTICITY. INHIBITORS OF EZH2 MIGHT THEREFORE INTERFERE WITH ONCOGENIC ACTIVITY OF NFATC1 AND BE USED IN TREATMENT OF PANCREATIC DUCTAL ADENOCARCINOMA.	2017	
                                                                                                                                                                                                                                                                                                                                                                                                                                                 
13  3227  37 HELICOBACTER PYLORI INFECTION-INDUCED H3SER10 PHOSPHORYLATION IN STEPWISE GASTRIC CARCINOGENESIS AND ITS CLINICAL IMPLICATIONS. BACKGROUND: OUR PREVIOUS WORKS HAVE DEMONSTRATED THAT HELICOBACTER PYLORI (HP) INFECTION CAN ALTER HISTONE H3 SERINE 10 PHOSPHORYLATION STATUS IN GASTRIC EPITHELIAL CELLS. HOWEVER, WHETHER HELICOBACTER PYLORI-INDUCED HISTONE H3 SERINE 10 PHOSPHORYLATION PARTICIPATES IN GASTRIC CARCINOGENESIS IS UNKNOWN. WE INVESTIGATE THE EXPRESSION OF HISTONE H3 SERINE 10 PHOSPHORYLATION IN VARIOUS STAGES OF GASTRIC DISEASE AND EXPLORE ITS CLINICAL IMPLICATION. MATERIALS AND METHODS: STOMACH BIOPSY SAMPLES FROM 129 PATIENTS WERE COLLECTED AND STAINED WITH HISTONE H3 SERINE 10 PHOSPHORYLATION, KI67, AND HELICOBACTER PYLORI BY IMMUNOHISTOCHEMISTRY STAINING, EXPRESSED AS LABELING INDEX. THEY WERE CATEGORIZED INTO NONATROPHIC GASTRITIS, CHRONIC ATROPHIC GASTRITIS, INTESTINAL METAPLASIA, LOW-GRADE INTRAEPITHELIAL NEOPLASIA, HIGH-GRADE INTRAEPITHELIAL NEOPLASIA, AND INTESTINAL-TYPE GASTRIC CANCER GROUPS. HELICOBACTER PYLORI INFECTION WAS DETERMINED BY EITHER (13) C-UREA BREATH TEST OR IMMUNOHISTOCHEMISTRY STAINING. RESULTS: IN HELICOBACTER PYLORI-NEGATIVE PATIENTS, LABELING INDEX OF HISTONE H3 SERINE 10 PHOSPHORYLATION WAS GRADUALLY INCREASED IN NONATROPHIC GASTRITIS, CHRONIC ATROPHIC GASTRITIS, INTESTINAL METAPLASIA GROUPS, PEAKED AT LOW-GRADE INTRAEPITHELIAL NEOPLASIA, AND DECLINED IN HIGH-GRADE INTRAEPITHELIAL NEOPLASIA AND GASTRIC CANCER GROUPS. IN HELICOBACTER PYLORI-INFECTED PATIENTS, LABELING INDEX OF HISTONE H3 SERINE 10 PHOSPHORYLATION FOLLOWED THE SIMILAR PATTERN AS ABOVE, WITH INCREASED EXPRESSION OVER THE CORRESPONDING HELICOBACTER PYLORI-NEGATIVE CONTROLS EXCEPT IN NONATROPHIC GASTRITIS PATIENT WHOSE LABELING INDEX WAS DECREASED WHEN COMPARED WITH HELICOBACTER PYLORI-NEGATIVE CONTROL. LABELING INDEX OF KI67 IN HELICOBACTER PYLORI-NEGATIVE GROUPS WAS HIGHER IN GASTRIC CANCER THAN CHRONIC ATROPHIC GASTRITIS AND LOW-GRADE INTRAEPITHELIAL NEOPLASIA GROUPS, AND HIGHER IN INTESTINAL METAPLASIA GROUP COMPARED WITH CHRONIC ATROPHIC GASTRITIS GROUP. IN HELICOBACTER PYLORI-POSITIVE GROUPS, KI67 LABELING INDEX WAS INCREASED STEPWISE FROM NONATROPHIC GASTRITIS TO GASTRIC CANCER EXCEPT SLIGHTLY DECREASE IN CHRONIC ATROPHIC GASTRITIS GROUP. IN ADDITION, WE NOTED THAT HISTONE H3 SERINE 10 PHOSPHORYLATION STAINING IS ACCOMPANIED WITH ITS LOCATION CHANGES FROM GASTRIC GLAND BOTTOM EXPANDED TO WHOLE GLAND AS DISEASE STAGE PROGRESS. CONCLUSIONS: THESE RESULTS INDICATE THAT STEPWISE GASTRIC CARCINOGENESIS IS ASSOCIATED WITH ALTERED HISTONE H3 SERINE 10 PHOSPHORYLATION, HELICOBACTER PYLORI INFECTION ENHANCES HISTONE H3 SERINE 10 PHOSPHORYLATION EXPRESSION IN THESE PROCESSES; IT IS ALSO ACCOMPANIED WITH HISTONE H3 SERINE 10 PHOSPHORYLATION LOCATION CHANGE FROM GLAND BOTTOM STAINING EXPAND TO WHOLE GLAND EXPRESSION. THE RESULTS SUGGEST THAT EPIGENETIC DYSREGULATION MAY PLAY IMPORTANT ROLES IN HELICOBACTER PYLORI-INDUCED GASTRIC CANCER.	2018	

14  1141  38 CONCERTED CELL AND IN VIVO SCREEN FOR PANCREATIC DUCTAL ADENOCARCINOMA (PDA) CHEMOTHERAPEUTICS. PDA IS A MAJOR CAUSE OF US CANCER-RELATED DEATHS. ONCOGENIC KRAS PRESENTS IN 90% OF HUMAN PDAS. KRAS MUTATIONS OCCUR EARLY IN PRE-NEOPLASTIC LESIONS BUT ARE INSUFFICIENT TO CAUSE PDA. OTHER CONTRIBUTING FACTORS EARLY IN DISEASE PROGRESSION INCLUDE CHRONIC PANCREATITIS, ALTERATIONS IN EPIGENETIC REGULATORS, AND TUMOR SUPPRESSOR GENE MUTATION. GPCRS ACTIVATE HETEROTRIMERIC G-PROTEINS THAT STIMULATE INTRACELLULAR CALCIUM AND ONCOGENIC KRAS SIGNALING, THEREBY PROMOTING PANCREATITIS AND PROGRESSION TO PDA. BY CONTRAST, RGS PROTEINS INHIBIT GI/Q-COUPLED GPCRS TO NEGATIVELY REGULATE PDA PROGRESSION. RGS16::GFP IS EXPRESSED IN RESPONSE TO CAERULEIN-INDUCED ACINAR CELL DEDIFFERENTIATION, EARLY NEOPLASIA, AND THROUGHOUT PDA PROGRESSION. IN GENETICALLY ENGINEERED MOUSE MODELS OF PDA, RGS16::GFP IS USEFUL FOR PRE-CLINICAL RAPID IN VIVO VALIDATION OF NOVEL CHEMOTHERAPEUTICS TARGETING EARLY LESIONS IN PATIENTS FOLLOWING SUCCESSFUL RESECTION OR AT HIGH RISK FOR PROGRESSING TO PDA. CULTURED PRIMARY PDA CELLS EXPRESS RGS16::GFP IN RESPONSE TO CYTOTOXIC DRUGS. A HISTONE DEACETYLASE INHIBITOR, TSA, STIMULATED RGS16::GFP EXPRESSION IN PDA PRIMARY CELLS, POTENTIATED GEMCITABINE AND JQ1 CYTOTOXICITY IN CELL CULTURE, AND GEM + TSA + JQ1 INHIBITED TUMOR INITIATION AND PROGRESSION IN VIVO. HERE WE ESTABLISH THE USE OF RGS16::GFP EXPRESSION FOR TESTING DRUG COMBINATIONS IN CELL CULTURE AND VALIDATION OF BEST CANDIDATES IN OUR RAPID IN VIVO SCREEN.	2020	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  
15  5116  24 POSITIVE REGULATION OF HUMAN TELOMERASE REVERSE TRANSCRIPTASE GENE EXPRESSION AND TELOMERASE ACTIVITY BY DNA METHYLATION IN PANCREATIC CANCER. AIM: WE SOUGHT TO DETERMINE THE ROLE OF TELOMERASE AND ITS CATALYTIC SUBUNIT HTERT IN PANCREATIC CANCER AND EVALUATE THE EPIGENETIC REGULATION OF HTERT BY PROMOTER METHYLATION. METHODS: THIRTY PAIRED SAMPLES OF PANCREATIC DUCTAL ADENOCARCINOMAS AND ADJACENT NORMAL TISSUE AND 12 CHRONIC PANCREATITIS SAMPLES WERE STUDIED. REVERSE TRANSCRIPTASE POLYMERASE CHAIN REACTION, TELOMERIC REPEAT AMPLIFICATION PROTOCOL ASSAY, AND METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION WERE PERFORMED TO ANALYZE HTERT EXPRESSION, TELOMERASE ACTIVITY, AND METHYLATION STATUS OF GENE PROMOTERS, RESPECTIVELY. RESULT: HTERT AND TELOMERASE ACTIVITY WERE UPREGULATED IN PANCREATIC CANCER COMPARED WITH PAIRED NORMAL TISSUES AND SAMPLES OF PANCREATITIS. HTERT EXPRESSION CORRELATED WITH TELOMERASE ACTIVITY (P \ .05) AND IN TURN CORRELATED POSITIVELY WITH HTERT PROMOTER METHYLATION (P \ .001) AND P16 PROMOTER METHYLATION. HTERT TRANSCRIPT EXPRESSION AND TELOMERASE ACTIVITY BOTH CONFERRED A WORSE OUTCOME BY UNIVARIATE AND MULTIVARIATE ANALYSIS (P \ .05). CONCLUSION: HTERT EXPRESSION AND TELOMERASE ACTIVITY ARE PREDICTORS OF POOR OUTCOME IN PANCREATIC CANCER. HTERT GENE EXPRESSION IS POSITIVELY REGULATED BY PROMOTER METHYLATION.	2009	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             
16   778  32 CELL-FREE DNA METHYLATION: THE NEW FRONTIERS OF PANCREATIC CANCER BIOMARKERS' DISCOVERY. PANCREATIC DUCTAL ADENOCARCINOMA (PDAC) IS AMONG THE MOST LETHAL CANCER TYPES WORLD-WIDE. ITS HIGH MORTALITY IS RELATED TO THE DIFFICULTY IN THE DIAGNOSIS, WHICH OFTEN OCCURS WHEN THE DISEASE IS ALREADY ADVANCED. AS OF TODAY, NO EARLY DIAGNOSTIC TESTS ARE AVAILABLE, WHILE ONLY A LIMITED NUMBER OF PROGNOSTIC TESTS HAVE REACHED CLINICAL PRACTICE. THE MAIN REASON IS THE LACK OF RELIABLE BIOMARKERS THAT ARE ABLE TO CAPTURE THE EARLY DEVELOPMENT OR THE PROGRESSION OF THE DISEASE. HENCE, THE DISCOVERY OF BIOMARKERS FOR EARLY DIAGNOSIS OR PROGNOSIS OF PDAC REMAINS, DE FACTO, AN UNMET NEED. AN INCREASING NUMBER OF STUDIES HAS SHOWN THAT CELL-FREE DNA (CFDNA) METHYLATION ANALYSIS REPRESENTS A PROMISING NON-INVASIVE APPROACH FOR THE DISCOVERY OF BIOMARKERS WITH DIAGNOSTIC OR PROGNOSTIC POTENTIAL. IN PARTICULAR, CFDNA METHYLATION COULD BE UTILIZED FOR THE IDENTIFICATION OF DISEASE-SPECIFIC SIGNATURES IN PRE-NEOPLASTIC LESIONS OR CHRONIC PANCREATITIS (CP), REPRESENTING A SENSITIVE AND NON-INVASIVE METHOD OF EARLY DIAGNOSIS OF PDAC. IN THIS REVIEW, WE WILL DISCUSS THE ADVANTAGES AND PITFALLS OF CFDNA METHYLATION STUDIES. FURTHER, WE WILL PRESENT THE CURRENT ADVANCES IN THE DISCOVERY OF PANCREATIC CANCER BIOMARKERS WITH EARLY DIAGNOSTIC OR PROGNOSTIC POTENTIAL, FOCUSING ON PANCREAS-SPECIFIC (E.G., CUX2 OR REG1A) OR ABNORMAL (E.G., ADAMTS1 OR BNC1) CFDNA METHYLATION SIGNATURES IN HIGH RISK PRE-NEOPLASTIC CONDITIONS AND PDAC.	2019	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     
17  3445  40 HYPERMETHYLATION OF ITGA4, TFPI2 AND VIMENTIN PROMOTERS IS INCREASED IN INFLAMED COLON TISSUE: PUTATIVE RISK MARKERS FOR COLITIS-ASSOCIATED CANCER. PURPOSE: EPIGENETIC SILENCING OF TUMOR SUPPRESSOR GENES IS INVOLVED IN EARLY TRANSFORMING EVENTS AND HAS A HIGH IMPACT ON COLORECTAL CARCINOGENESIS. LIKEWISE, COLON CANCERS THAT DERIVE FROM CHRONICALLY INFLAMED BOWEL DISEASES FREQUENTLY EXHIBIT EPIGENETIC CHANGES. BUT THERE IS LITTLE DATA ABOUT EPIGENETIC ABERRATIONS CAUSING COLORECTAL CANCER IN CHRONICALLY INFLAMED TISSUE. THE AIM OF THE PRESENT STUDY WAS TO EVALUATE THE ABERRANT GAIN OF METHYLATION IN THE GENE PROMOTERS OF VIM, TFPI2 AND ITGA4 AS PUTATIVE EARLY MARKERS IN THE DEVELOPMENT FROM INFLAMED TISSUE VIA PRECANCEROUS LESIONS TOWARD COLORECTAL CANCER. METHODS: INITIAL SCREENING OF DIFFERENT CANCER CELL LINES BY USING METHYLATION-SPECIFIC PCR REVEALED A PUTATIVE COLON CANCER-SPECIFIC METHYLATION PATTERN. ADDITIONALLY, A DEMETHYLATION ASSAY WAS PERFORMED TO INVESTIGATE THE METHYLATION-DEPENDENT GENE SILENCING OF ITGA4. THE CANDIDATE MARKERS WERE ANALYZED IN COLONIC TISSUE SPECIMENS FROM PATIENTS WITH COLORECTAL CANCER (N = 15), ADENOMAS (N = 76), SERRATED LESIONS (N = 13), CHRONIC INFLAMMATION (N = 10) AND NORMAL MUCOSAL SAMPLES (N = 9). RESULTS: A HIGH METHYLATION FREQUENCY OF VIM (55.6 %) WAS OBSERVED IN NORMAL COLON TISSUE, WHEREAS ITGA4 AND TFPI2 WERE COMPLETELY UNMETHYLATED IN CONTROLS. A SIGNIFICANT GAIN OF METHYLATION FREQUENCY WITH PROGRESSION OF DISEASE AS WELL AS AN AGE-DEPENDENT EFFECT WAS DETECTABLE FOR TFPI2. ITGA4 METHYLATION FREQUENCY WAS HIGH IN PRECANCEROUS AND CANCEROUS TISSUES AS WELL AS IN INFLAMMATORY BOWEL DISEASES (IBD). CONCLUSION: THE ALREADY ESTABLISHED METHYLATION MARKER VIM DOES NOT PERMIT A SPECIFIC AND SENSITIVE DISCRIMINATION OF HEALTHY AND NEOPLASTIC TISSUE. THE METHYLATION MARKERS ITGA4 AND TFPI2 SEEM TO BE SUITABLE RISK MARKERS FOR INFLAMMATION-ASSOCIATED COLON CANCER.	2015	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      
18   402  36 ANALYSIS OF APOPTOSOME DYSREGULATION IN PANCREATIC CANCER AND OF ITS ROLE IN CHEMORESISTANCE. THE APOPTOSOME IS A MULTIPROTEIN COMPLEX MEDIATING THE MITOCHONDRIAL PATHWAY OF CELL DEATH. ITS IMPORTANCE DURING DEVELOPMENT HAS BEEN CLEARLY DEMONSTRATED BY KNOCKING OUT KEY GENES IN MOUSE. APAF1 IS THE CORE PROTEIN OF THE APOPTOSOME AND ITS DOSAGE IS ALSO CRITICAL IN VARIOUS CANCER TYPES, I.E., MELANOMA, GERM LINE TUMOR, GASTROINTESTINAL CANCER AND B-TYPE CHRONIC LYMPHOCYTIC LEUKEMIA. THIS IS GENERALLY DUE TO INACTIVATION OF THE APAF1 LOCUS BY EPIGENETIC PHENOMENA OR BY ACTIVITY OF PROMOTER REGULATORS. WE INVESTIGATED THE PUTATIVE ROLES OF THE APOPTOSOME IN PANCREATIC DUCTAL ADENOCARCINOMA (PDAC). WE FOUND THAT BOTH APAF1 MRNA AND PROTEIN ARE DYSREGULATED IN HUMAN PDAC SAMPLES. SIMILARLY, SEVERAL PDAC CELL LINES EXHIBITED VARIABLE LEVELS OF BOTH APAF1 PROTEIN AND MRNA. THE RESPONSE TO CELL DEATH INDUCTION AND ITS BIOCHEMICAL FEATURES WERE ASSESSED BY TREATMENT OF EACH LINE WITH COMMONLY USED CHEMOTHERAPEUTIC AGENTS. WE FOUND THAT THE APOPTOSOME PATHWAY WAS NOT FUNCTIONAL IN MOST CELL LINES UPON CYTOCHROME C RELEASE FROM MITOCHONDRIA. IN ADDITION, WE RESTORED APAF1 AND CASPASE-9 DOSAGE IN PANC-1 CELLS, WHERE THE APOPTOSOME IS DOWNREGULATED, BY OVEREXPRESSING THE MURINE CDNA OF THE TWO MOLECULES, AND WE IMPROVED THE DEATH RESPONSE TO CHEMOTHERAPEUTIC AGENTS.	2007	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          
19  2843  38 FREQUENT CPG ISLAND METHYLATION IN PRECURSOR LESIONS AND EARLY GASTRIC ADENOCARCINOMAS. GASTRIC CARCINOGENESIS INVOLVES MULTIPLE GENETIC AND EPIGENETIC ALTERATIONS. EPIGENETIC SILENCING OF TUMOR-RELATED GENES DUE TO CPG ISLAND METHYLATION (CIM) HAS BEEN RECENTLY REPORTED IN GASTRIC CANCER, BUT THE ROLE IN PRECURSOR LESIONS IS NOT WELL UNDERSTOOD. WE ANALYSED THE METHYLATION STATUS OF THE TUMOR SUPPRESSOR GENE P16, THE DNA MISMATCH REPAIR GENE HMLH1, AND FOUR CPG ISLANDS (MINT1, MINT2, MINT25, AND MINT31) USING METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION IN 35 POLYPOID ADENOMAS AND 46 FLAT DYSPLASIAS UNASSOCIATED WITH CARCINOMA, 34 EARLY ADENOCARCINOMAS (T1N0M0) AND ASSOCIATED ADENOMAS/DYSPLASIAS, AND CORRESPONDING ADJACENT NON-NEOPLASTIC MUCOSA. THE EXTENT OF CIM WAS DEFINED BY THE FRACTION OF METHYLATED LOCI (METHYLATION INDEX), AND COMPARED WITH PREVIOUSLY CHARACTERIZED GENETIC ALTERATIONS (MICROSATELLITE INSTABILITY (MSI) AND APC GENE MUTATION). WE FOUND THAT METHYLATION OF P16 WAS MORE FREQUENT IN ADENOCARCINOMA-ASSOCIATED DYSPLASIAS/ADENOMAS (29%) AND ADENOCARCINOMAS (44%) AS COMPARED TO FLAT DYSPLASIAS (4%) AND ADENOMAS (18%) UNASSOCIATED WITH ADENOCARCINOMA (P=0.001). THE MEAN METHYLATION INDEX INCREASED FROM NORMAL/CHRONIC GASTRITIS (CG) MUCOSA (0.09) TO INTESTINAL METAPLASIA (IM) (0.16), FLAT DYSPLASIAS (0.40) OR POLYPOID ADENOMAS (0.41) UNASSOCIATED WITH CARCINOMA, DYSPLASIAS/ADENOMAS ASSOCIATED WITH CARCINOMA (0.44), AND ADENOCARCINOMAS (0.44). THERE WAS NO DIFFERENCE IN FREQUENCIES OF HIGH-LEVEL CPG ISLAND METHYLATION (CIM-H, METHYLATION INDEX > OR =0.5) AMONG FLAT DYSPLASIAS (50%) AND POLYPOID ADENOMAS (51%) UNASSOCIATED WITH CARCINOMA, DYSPLASIAS/ADENOMAS ASSOCIATED WITH ADENOCARCINOMA (47%), AND ADENOCARCINOMA (47%). CIM-H WAS PRESENT IN 15% OF IM, BUT NOT IN NORMAL/CG MUCOSA. THERE WAS A SIGNIFICANT CORRELATION BETWEEN METHYLATION OF HMLH1 AND HIGH-LEVEL OF MICROSATELLITE INSTABILITY (MSI-H): METHYLATION OF HMLH1 WAS PRESENT IN 71% OF MSI-H TUMORS, BUT ONLY 8% OF MSI-LOW TUMORS AND 13% OF MICROSATELLITE-STABLE TUMORS (P=0.0001). THERE WAS NO STATISTICAL DIFFERENCE BETWEEN METHYLATION INDEX AND APC MUTATION. OUR RESULTS INDICATE THAT CONCURRENT PROMOTER METHYLATION IS AN EARLY AND FREQUENT EVENT IN GASTRIC TUMORIGENESIS, INCLUDING BOTH MSI-H AND MICROSATELLITE-STABLE NEOPLASMS. METHYLATION OF THE P16 GENE MAY CONTRIBUTE TO THE MALIGNANT TRANSFORMATION OF GASTRIC PRECURSOR LESIONS.	2004	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              
20  6134  17 THE EPIGENETICALLY-REGULATED MIR-34A TARGETING C-SRC SUPPRESSES RAF/MEK/ERK SIGNALING PATHWAY IN K-562 CELLS. PREVIOUS REPORTS SHOW THAT MIR-34A SUPPRESSED K-562 CELL PROLIFERATION AND CONTRIBUTED TO MEGAKARYOCYTIC DIFFERENTIATION OF K-562 CELLS. HERE, WE REPORTED THAT MIR-34A, A TUMOR SUPPRESSOR GENE, IS DOWN-REGULATED IN THE K-562 CELLS AND CHRONIC MYELOID LEUKEMIA (CML) PATIENTS DUE TO ABERRANT DNA HYPERMETHYLATION. C-SRC IS A TARGET OF MIR-34A. RESTORING MIR-34A EXPRESSION RESULTED IN DOWN-REGULATION OF C-SRC AND PHOSPHORYLATED (TYR416) C-SRC PROTEIN IN K-562 CELLS, WHICH CONSEQUENTLY TRIGGERED SUPPRESSION OF THE RAF/MEK/ERK SIGNALING PATHWAY TO DECREASE CELL PROLIFERATION.	2017