1 6596 152 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 2 1141 27 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 3 672 29 BRAF, KRAS AND HELICOBACTER PYLORI EPIGENETIC CHANGES-ASSOCIATED CHRONIC GASTRITIS IN EGYPTIAN PATIENTS WITH AND WITHOUT GASTRIC CANCER. WE AIMED TO STUDY MLH1 AND MGMT METHYLATION STATUS IN HELICOBACTER PYLORI-ASSOCIATED CHRONIC GASTRITIS IN EGYPTIAN PATIENTS WITH AND WITHOUT GASTRIC CANCER. 39 PATIENTS WERE INCLUDED IN OUR STUDY. THEY WERE DIVIDED INTO 2 GROUPS; PATIENTS WITHOUT (GROUP I) AND WITH GASTRIC ADENOCARCINOMA (GROUP II). PATIENTS WERE SUBJECTED TO CLINICAL EXAMINATION, ABDOMINAL ULTRASOUND AND UPPER ENDOSCOPY FOR GASTRIC BIOPSY. BIOPSIES WERE SUBJECTED TO UREASE TEST, HISTOLOGICAL EXAMINATION, AND DNA PURIFICATION. H. PYLORI, BRAF, KRAS, MLH1 AND MGMT METHYLATION WERE ASSESSED BY QUANTITATIVE PCR. DNA SEQUENCING WAS PERFORMED TO ASSESS BRAF AND KRAS GENES MUTATION. QPCR OF H. PYLORI WAS SIGNIFICANTLY HIGHER IN PATIENTS WITH ADENOCARCINOMA (GROUP II) THAN THOSE WITHOUT ADENOCARCINOMA (GROUP I); WITH A P < 0.001 AS WELL AS IN PATIENTS WITH AGE ABOVE 50 YEARS WITH A P VALUE = 0.008. BY APPLYING LOGISTIC REGRESSION ANALYSIS IT WAS REPORTED THAT THE H. PYLORI QPCR IS A SIGNIFICANT PREDICTOR TO THE ADENOCARCINOMA WITH OR = 1.025 (95 % CI: 1. 002-1.048), WITH SENSITIVITY OF 90 % AND SPECIFICITY OF 100 %. ADENOCARCINOMA PATIENTS HAD A SIGNIFICANTLY HIGHER MEAN AGE AND LEVELS OF H. PYLORI, BRAF, K-RAS, METHYLATED MGMT AND METHYLATED MLH1 THAN THOSE OF GASTRITIS PATIENTS. DNA SEQUENCE ANALYSIS OF BRAF (CODON 12) AND KRAS (CODON 600) HAD GENES MUTATION IN GASTRIC ADENOCARCINOMA VERSUS CHRONIC GASTRITIS. CONCLUSION: H. PYLORI MAY CAUSE EPIGENETIC CHANGES PREDISPOSING THE PATIENTS TO CANCER STOMACH. ESTIMATION OF H. PYLORI BY QPCR CAN BE A GOOD PREDICTOR TO ADENOCARCINOMA. BRAF AND KRAS GENES MUTATION WERE REVELED IN GASTRITIS AND ADENOCARCINOMA PATIENTS. 2016 4 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 5 507 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 6 3413 35 HSA-MIR-29C AND HSA-MIR-135B DIFFERENTIAL EXPRESSION AS POTENTIAL BIOMARKER OF GASTRIC CARCINOGENESIS. AIM: TO INVESTIGATE THE EXPRESSION PROFILES OF HSA-MIR-29C AND HSA-MIR-135B IN GASTRIC MUCOSAL SAMPLES AND THEIR VALUES AS GASTRIC CARCINOGENESIS BIOMARKERS. METHODS: THE EXPRESSION LEVELS OF HSA-MIR-29C AND HSA-MIR-135B IN NORMAL GASTRIC MUCOSA, NON-ATROPHIC CHRONIC GASTRITIS, INTESTINAL METAPLASIA AND INTESTINAL-TYPE GASTRIC ADENOCARCINOMA WERE ANALYSED USING QUANTITATIVE REAL-TIME PCR. THE DIFFERENCE BETWEEN HSA-MIR-29C AND HSA-MIR-135B EXPRESSION PROFILES IN THE GROUPED SAMPLES WAS EVALUATED BY ANOVA AND STUDENT'S T-TEST TESTS. THE RESULTS WERE ADJUSTED FOR MULTIPLE TESTING BY USING BONFERRONI'S CORRECTION. P VALUES 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 16 4601 44 NDRG2 MRNA LEVELS AND MIR-28-5P AND MIR-650 ACTIVITY IN CHRONIC LYMPHOCYTIC LEUKEMIA. BACKGROUND: NDRG2 IS IDENTIFIED AS A TUMOR SUPPRESSOR GENE IN MANY TUMORS, AND FUNCTIONS IN CELL PROLIFERATION, DIFFERENTIATION AND APOPTOSIS. RECENT DATA INDICATE THAT NDRG2 EXPRESSION IS UP-REGULATED BY TP53. MOREOVER, PROPOSED MECHANISMS OF NDRG2 INACTIVATION INCLUDE EPIGENETIC SILENCING OF THE NDRG2 PROMOTER AND DOWN-REGULATION BY MICRORNAS (MIRNAS). HOWEVER, FEW STUDIES HAVE EVER BEEN DONE ON THE ROLE OF NDRG2 AND THE NDRG2-REGULATING MIRNAS INTERFERENCE IN CHRONIC LYMPHOCYTIC LEUKEMIA (CLL). METHODS: NDRG2 AND MICRORNAS MRNA LEVELS IN CLL SUBJECTS WERE ASSESSED BY QUANTITATIVE REAL-TIME POLYMERASE CHAIN REACTION (QRT-PCR). THE DUAL-LUCIFERASE REPORTER ASSAY WAS PERFORMED TO DETERMINE NDRG2-RELATED MIRNAS. LOW EXPRESSION OF MATURE EXOGENOUS MIRNAS IN CLL CELLS WAS ESTABLISHED BY TRANSIENT TRANSFECTION. NDRG2 PROTEIN LEVELS IN CLL CELLS WERE DETECTED BY WESTERN BLOT. IN ADDITION, FLOW CYTOMETRY WAS CONDUCTED TO EXAMINE THE APOPTOSIS OF CLL CELLS. RESULTS: LOWER EXPRESSION OF NDRG2 WAS FOUND IN THE B-CELLS FROM 102 CLL PATIENTS COMPARED THE 40 NORMAL SUBJECTS (P < 0.001). PATIENTS WITH ADVANCED BINET STAGE (P = 0.001), HIGH LACTATE DEHYDROGENASE (LDH) LEVEL (P = 0.036), UN-MUTATED IMMUNOGLOBULIN HEAVY CHAIN VARIABLE REGION GENE (IGHV) (P = 0.004) AND THOSE WITH P53 ABERRATIONS (P < 0.001) HAD A MARKEDLY LOWER LEVELS OF NDRG2 MRNA. THIS DECREASE WAS ASSOCIATED WITH BRIEFER TIME-TO-TREATMENT (P = 0.001) AND POORER SURVIVAL (P < 0.001). HIGH EXPRESSION OF MIR-28-5P AND MIR-650 WAS ASSOCIATED WITH BINET B/C STAGE (P = 0.044) AND IGHV UN-MUTATED (P = 0.011), AS WELL AS BINET B/C STAGE (P = 0.013) AND P53 ABERRATIONS (P = 0.037), RESPECTIVELY. INHIBITION OF MIR-28-5P OR MIR-650 COULD INDUCE MORE APOPTOSIS IN CLL CELLS WITH GERMLINE TP53. CONCLUSIONS: NDRG2 MRNA LEVELS MIGHT BE A USEFUL PROGNOSTIC VARIABLE FOR PATIENTS OF CLL AND UP-REGULATING NDRG2 TRANSCRIPTION MAY BE A THERAPY APPROACH IN CLL WITHOUT P53 ABERRATIONS. 2018 17 6386 36 THE ROLE OF QUANTITATIVE NPTX2 HYPERMETHYLATION AS A NOVEL SERUM DIAGNOSTIC MARKER IN PANCREATIC CANCER. OBJECTIVES: THE MAJORITY OF PANCREATIC CANCERS ARE FOUND TO BE UNRESECTABLE, AND THE ONLY CHANCE FOR CURE LIES ON EARLY DETECTION AND COMPLETE RESECTION. SEVERAL GENES HAVE BEEN DISCOVERED TO BE ABERRANTLY METHYLATED IN PRIMARY PANCREATIC CANCER TISSUE, AND THIS CANCER DNA CAN BE DETECTED IN THE PLASMA. THE AIMS OF THIS STUDY WERE TO DEVELOP A NOVEL DIAGNOSTIC MARKER BASED ON EPIGENETIC CHARACTERISTICS OF PANCREATIC CANCER. METHODS: WE ENROLLED 104 PATIENTS WITH PANCREATIC CANCER, 60 WITH CHRONIC PANCREATITIS, AND 5 WITH BENIGN BILIARY STONE DISEASES. THE BLOOD SAMPLES WERE COLLECTED BEFORE SURGERY OR ANY KINDS OF TREATMENT MODALITIES. DNA WAS EXTRACTED FROM THE PLASMA OF EACH PATIENT, AND NPTX2 (NEURONAL PENTRAXIN II) CPG ISLAND HYPERMETHYLATION WAS EXAMINED QUANTITATIVELY BY REAL-TIME POLYMERASE CHAIN REACTION. RESULTS: NPTX2 HYPERMETHYLATION LEVELS WERE SIGNIFICANTLY HIGHER COMPARED WITH CHRONIC PANCREATITIS (P = 0.016). THE SENSITIVITY AND SPECIFICITY WERE 80% AND 76%, RESPECTIVELY (CUTOFF = 0.015). NPTX2 GENE HYPERMETHYLATION LEVEL WAS SIGNIFICANTLY ELEVATED IN CORRELATION WITH HIGHER AMERICAN JOINT COMMITTEE ON CANCER STAGES. CONCLUSIONS: THE ABERRANTLY METHYLATED NPTX2 GENE MAY HELP TO DISTINGUISH BETWEEN CHRONIC PANCREATITIS AND PANCREATIC CANCER WITH CONVENTIONAL DIAGNOSTIC TOOLS AND COULD BECOME A VALUABLE DIAGNOSTIC MARKER. 2012 18 2439 40 EPIGENETIC SILENCING OF THE MLH1 PROMOTER IN RELATION TO THE DEVELOPMENT OF GASTRIC CANCER AND ITS USE AS A BIOMARKER FOR PATIENTS WITH MICROSATELLITE INSTABILITY: A SYSTEMATIC ANALYSIS. BACKGROUND/AIMS: HUMAN MUTL HOMOLOG 1 (MLH1) PROMOTER METHYLATION WAS REPORTED IN GASTRIC CANCER (GC). THIS STUDY DETERMINED THE CLINICOPATHOLOGICAL, PROGNOSTIC, AND DIAGNOSTIC EFFECTS OF MLH1 PROMOTER METHYLATION IN GC. METHODS: THE COMBINED ODDS RATIO (OR) OR HAZARD RATIO (HR) AND THEIR CORRESPONDING 95% CONFIDENCE INTERVALS (95% CI) WERE CALCULATED. THE POOLED SENSITIVITY, SPECIFICITY, AND AREA UNDER THE CURVE (AUC) WERE ANALYZED. RESULTS: A TOTAL OF 4654 GC PATIENTS AND 3669 NON-MALIGNANT CONTROLS WERE IDENTIFIED IN THIS SYSTEMATIC ANALYSIS. MLH1 PROMOTER METHYLATION WAS SIGNIFICANTLY HIGHER IN GC SAMPLES THAN IN GASTRIC ADENOMAS, CHRONIC GASTRITIS, ADJACENT TISSUES, NORMAL GASTRIC MUCOSA, AND NORMAL HEALTHY BLOOD SAMPLES, BUT IT EXHIBITED A SIMILAR FREQUENCY IN GC VS. INTESTINAL METAPLASIA AND DYSPLASIA SAMPLES. MLH1 PROMOTER METHYLATION CORRELATED WITH AGE AND MICROSATELLITE INSTABILITY (MSI), BUT IT WAS NOT ASSOCIATED WITH GENDER, H. PYLORI INFECTION, SMOKING, DRINKING BEHAVIORS, PATHOLOGICAL HISTOLOGY, TUMOR DIFFERENTIATION, CLINICAL STAGE, LYMPH NODE STATUS, DISTANT METASTASIS, OR OVERALL SURVIVAL OF GC. MLH1 PROMOTER METHYLATION EXHIBITED A POOR SENSITIVITY VALUE (< 0.5) IN PATIENTS WITH GC COMPARED WITH ADJACENT TISSUES, GASTRIC ADENOMAS, CHRONIC GASTRITIS, NORMAL GASTRIC MUCOSA, AND NORMAL HEALTHY BLOOD SAMPLES. THE POOLED SENSITIVITY, SPECIFICITY, AND AUC OF MLH1 PROMOTER METHYLATION IN GC WITH MSI VS. GC WITH MICROSATELLITE STABILITY (MSS) SAMPLES WERE 0.64, 0.96, AND 0.90, RESPECTIVELY. CONCLUSIONS: OUR RESULTS SUGGEST THAT THE DETECTION OF MLH1 PROMOTER METHYLATION MAY BE A POTENTIAL PROGNOSTIC BIOMARKER FOR GC PATIENTS WITH MSI. 2018 19 2767 45 EXPRESSION, PROGNOSTIC VALUE, AND FUNCTIONAL MECHANISM OF THE KDM5 FAMILY IN PANCREATIC CANCER. BACKGROUND: THE HISTONE LYSINE DEMETHYLASE KDM5 FAMILY IS AN IMPORTANT EPIGENETIC STATE-MODIFYING ENZYME FAMILY. INCREASING EVIDENCE SUPPORTS THAT EPIGENETIC ABNORMALITIES IN THE KDM5 FAMILY ARE RELATED TO MULTIPLE CANCERS IN HUMANS. HOWEVER, THE ROLE OF THE KDM5 FAMILY IN PANCREATIC CANCER IS NOT CLEAR, AND RELATED RESEARCH IS VERY SCARCE. METHODS: R SOFTWARE, KAPLAN-MEIER PLOTTER, CBIOPORTAL, TIMER, LINKEDOMICS, STRING, METASCAPE, TISIDB, AND THE GSCA LITE ONLINE TOOL WERE UTILIZED FOR BIOINFORMATICS ANALYSIS. RESULTS: KDM5A/B/C WAS SIGNIFICANTLY OVEREXPRESSED IN MANY KINDS OF TUMOR TISSUES, INCLUDING PANCREATIC ADENOCARCINOMA (PAAD), WHILE THE EXPRESSION OF KDM5D WAS SIGNIFICANTLY DOWNREGULATED. THE HIGH EXPRESSION OF KDM5A/B/C WAS RELATED TO POOR CLINICAL FEATURES, SUCH AS WORSE TREATMENT EFFICACY, HIGHER TUMOR GRADE, AND MORE ADVANCED CLINICAL STAGE. PATIENTS WITH A FAMILY HISTORY OF BREAST CANCER AND MELANOMA, HISTORY OF DRINKING OR HISTORY CHRONIC PANCREATITIS WERE MORE LIKELY TO HAVE KDM5A/B/C GENE ABNORMALITIES, WHICH WERE RELATED TO A VARIETY OF ADVERSE CLINICAL FEATURES. THE RESULTS OF GENE ONTOLOGY (GO) AND KYOTO ENCYCLOPEDIA OF GENES AND GENOMES (KEGG) PATHWAY ANALYSES OF THE KDM5 FAMILY AND ITS 800 CO-EXPRESSED GENES SHOWED THAT MANY GENE TERMS RELATED TO CELL PROLIFERATION, MIGRATION AND MANY CARCINOGENIC PATHWAYS. NOTABLY, WE FOUND THAT THE EXPRESSION LEVEL OF KDM5A/B/C WAS POSITIVELY CORRELATED WITH THE EXPRESSION OF MULTIPLE KEY DRIVER GENES SUCH AS KRAS, BRCA1, AND BRCA2 ETC. IN ADDITION, PPI NETWORK ANALYSIS SHOWED KDM5 FAMILY PROTEINS HAVE STRONG INTERACTIONS WITH HISTONE DEACETYLASE FAMILY 1 (HDAC1), WHICH COULD MODIFY THE LYSINES OF HISTONE H3, AND CO-ACT ON MANY PATHWAYS, INCLUDING THE "LONGEVITY-REGULATING PATHWAY" AND "NOTCH SIGNALING PATHWAY". MOREOVER, THE UPREGULATION OF KDM5A/B/C EXPRESSION WAS ASSOCIATED WITH AN INCREASE IN THE INFILTRATION OF B CELLS, CD8(+) T CELLS AND OTHER INFILTRATING IMMUNE LYMPHOCYTES AND THE EXPRESSION LEVELS OF IMMUNE MOLECULES SUCH AS NT5E AND CD274. INTERESTINGLY, THE OVEREXPRESSION OF KDM5A/C WAS ALSO CORELATED WITH REDUCED SENSITIVITY OF PANCREATIC CANCER CELLS TO MANY KINDS OF PANCREATIC CANCER-TARGETING OR CHEMOTHERAPEUTIC DRUGS, INCLUDING AXITINIB AND GEMCITABINE. CONCLUSION: KDM5 FAMILY MEMBERS MAY BE PROGNOSTIC MARKERS AND NEW THERAPEUTIC TARGETS FOR PATIENTS WITH PANCREATIC CANCER. 2022 20 3227 34 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