1 1471 130 DISTINCT GLOBAL DNA METHYLATION STATUS IN B-CELL LYMPHOMAS: IMMUNOHISTOCHEMICAL STUDY OF 5-METHYLCYTOSINE AND 5-HYDROXYMETHYLCYTOSINE. LYMPHOMAS ARE MALIGNANT NEOPLASMS COMPOSED OF LYMPHOID CELLS AT VARIOUS DEVELOPMENTAL STAGES AND LINEAGES. RECENT ADVANCES IN COMPREHENSIVE GENOMIC ANALYSES IN ACUTE MYELOID LEUKEMIA HAVE REVEALED PREVALENT MUTATIONS IN REGULATORS OF EPIGENETIC PHENOMENA INCLUDING GLOBAL DNA METHYLATION STATUS. THE EXAMPLES INCLUDE MUTATIONS IN ISOCITRATE DEHYDROGENASE 1 (IDH1), IDH2, AND TEN-ELEVEN TRANSLOCATION 2. THESE MUTATIONS ARE PROPOSED TO INHIBIT CONVERSION OF 5-METHYLCYTOSINE (5 MC) TO 5-HYDROXYMETHYLCYTOSINE (5 HMC), LEADING TO GLOBAL ACCUMULATION OF 5 MC. THESE CHANGES IN GLOBAL DNA METHYLATION STATUS CAN BE VISUALIZED IMMUNOHISTOCHEMICALLY USING SPECIFIC ANTIBODIES AGAINST 5 MC AND 5 HMC. WE EXAMINED THE GLOBAL DNA METHYLATION STATUS OF B-CELL LYMPHOMAS AND THAT OF THEIR NORMAL COUNTERPARTS BY IMMUNOHISTOCHEMISTRY FOR 5 MC AND 5 HMC. NON-TUMOR LYMPHOID CELLS INSIDE GERMINAL CENTERS (GC) IN REACTIVE LYMPHOID HYPERPLASIA (RLH) WERE STAINED POSITIVE FOR 5 MC, BUT THEY WERE NEGATIVE FOR 5 HMC. SIMILARLY, FOLLICULAR LYMPHOMAS, WHOSE POSTULATED NORMAL COUNTERPARTS ARE CENTROCYTES IN GCS, WERE 5 MC-POSITIVE BUT 5 HMC-NEGATIVE BY IMMUNOHISTOCHEMISTRY. THIS IMMUNOSTAINING PATTERN WAS ALSO OBSERVED IN BURKITT LYMPHOMA. IN CONTRAST, NON-TUMOR LYMPHOID CELLS IN MANTLE ZONES WERE STAINED POSITIVE FOR 5 MC AS WELL AS FOR 5 HMC. LIKEWISE, MOST MANTLE CELL LYMPHOMAS, WHOSE POSTULATED NORMAL COUNTERPARTS ARE MANTLE ZONE B CELLS IN RLH, WERE STAINED POSITIVE FOR 5 MC AS WELL AS FOR 5 HMC. THIS IMMUNOSTAINING PATTERN WAS ALSO OBSERVED IN CHRONIC LYMPHOCYTIC LEUKEMIA/SMALL LYMPHOCYTIC LYMPHOMA. THESE RESULTS SUGGEST THAT, IN TERMS OF 5 MC/5 HMC IMMUNOHISTOCHEMISTRY, B-CELL LYMPHOMAS WITH DIFFERENT HISTOLOGICAL SUBTYPES ARE ASSOCIATED WITH DISTINCT GLOBAL DNA METHYLATION STATUSES THAT RESEMBLE THOSE OF THEIR POSTULATED NORMAL COUNTERPARTS. 2014 2 3666 28 INFECTION, STEM CELLS AND CANCER SIGNALS. THE ASSOCIATION OF CANCER WITH PRECEDING PARASITIC INFECTIONS HAS BEEN OBSERVED FOR OVER 200 YEARS. SOME SUCH CANCERS ARISE FROM INFECTION OF TISSUE STEM CELLS BY VIRUSES WITH INSERTION OF VIRAL ONCOGENES INTO THE HOST DNA (MOUSE POLYOMA VIRUS, MOUSE MAMMARY TUMOR VIRUS). IN OTHER CASES THE VIRUS DOES NOT INSERT ITS DNA INTO THE HOST CELLS, BUT RATHER COMMANDEERS THE METABOLISM OF THE INFECTED CELLS, SO THAT THE CELLS CONTINUE TO PROLIFERATE AND DO NOT DIFFERENTIATE (HUMAN PAPILLOMA VIRUS AND CERVICAL CANCER). CYTOPLASMIC EPSTEIN BARR VIRUS INFECTION IS ASSOCIATED WITH A SPECIFIC GENE TRANSLOCATION (IG/C-MYC) THAT ACTIVATES PROLIFERATION OF AFFECTED CELLS (BURKITT LYMPHOMA). IN CHRONIC OSTEOMYELITIS AN INFLAMMATORY REACTION TO THE INFECTION APPEARS TO ACT THROUGH PRODUCTION OF INFLAMMATORY CYTOKINES AND OXYGEN RADICAL FORMATION TO INDUCE EPITHELIAL CANCERS. INFECTION WITH HELICOBACTER PYLORI LEADS TO EPIGENETIC CHANGES IN METHYLATION AND INFECTION BY A PARASITE. CLONORCHIS SINENSIS ALSO ACTS AS A PROMOTER OF CANCER OF THE BILE DUCTS OF THE LIVER (CHOLANIOCARCINOMA). THE COMMON THREAD AMONG THESE DIVERSE PATHWAYS IS THAT THE INFECTIONS ACT TO ALTER TISSUE STEM CELL SIGNALING WITH CONTINUED PROLIFERATION OF TUMOR TRANSIT AMPLIFYING CELLS. 2011 3 1492 24 DNA HYDROXYMETHYLATION BY TEN-ELEVEN TRANSLOCATION METHYLCYTOSINE DIOXYGENASE 1 AND 3 REGULATES NOCICEPTIVE SENSITIZATION IN A CHRONIC INFLAMMATORY PAIN MODEL. BACKGROUND: TEN-ELEVEN TRANSLOCATION METHYLCYTOSINE DIOXYGENASE CONVERTS 5-METHYLCYTOSINE IN DNA TO 5-HYDROXYMETHYLCYTOSINE, WHICH PLAYS AN IMPORTANT ROLE IN GENE TRANSCRIPTION. ALTHOUGH 5-HYDROXYMETHYLCYTOSINE IS ENRICHED IN MAMMALIAN NEURONS, ITS REGULATORY FUNCTION IN NOCICEPTIVE INFORMATION PROCESSING IS UNKNOWN. METHODS: THE GLOBAL LEVELS OF 5-HYDROXYMETHYLCYTOSINE AND TEN-ELEVEN TRANSLOCATION METHYLCYTOSINE DIOXYGENASE WERE MEASURED IN SPINAL CORDS IN MICE TREATED WITH COMPLETE FREUND'S ADJUVANT. IMMUNOBLOTTING, IMMUNOHISTOCHEMISTRY, AND BEHAVIORAL TESTS WERE USED TO EXPLORE THE DOWNSTREAM TEN-ELEVEN TRANSLOCATION METHYLCYTOSINE DIOXYGENASE-DEPENDENT SIGNALING PATHWAY. RESULTS: COMPLETE FREUND'S ADJUVANT-INDUCED NOCICEPTION INCREASED THE MEAN LEVELS (+/- SD) OF SPINAL 5-HYDROXYMETHYLCYTOSINE (178 +/- 34 VS. 100 +/- 21; P = 0.0019), TEN-ELEVEN TRANSLOCATION METHYLCYTOSINE DIOXYGENASE-1 (0.52 +/- 0.11 VS. 0.36 +/- 0.064; P = 0.0088), AND TEN-ELEVEN TRANSLOCATION METHYLCYTOSINE DIOXYGENASE-3 (0.61 +/- 0.13 VS. 0.39 +/- 0.08; P = 0.0083) COMPARED WITH LEVELS IN CONTROL MICE (N = 6/GROUP). THE KNOCKDOWN OF TEN-ELEVEN TRANSLOCATION METHYLCYTOSINE DIOXYGENASE-1 OR TEN-ELEVEN TRANSLOCATION METHYLCYTOSINE DIOXYGENASE-3 ALLEVIATED THERMAL HYPERALGESIA AND MECHANICAL ALLODYNIA, WHEREAS OVEREXPRESSION CYTOSINETHEM IN NAIVE MICE (N = 6/GROUP). DOWN-REGULATION OF SPINAL TEN-ELEVEN TRANSLOCATION METHYLCYTOSINE DIOXYGENASE-1 AND TEN-ELEVEN TRANSLOCATION METHYLCYTOSINE DIOXYGENASE-3 ALSO REVERSED THE INCREASES IN FOS EXPRESSION (123 +/- 26 VS. 294 +/- 6; P = 0.0031; AND 140 +/- 21 VS. 294 +/- 60; P = 0.0043, RESPECTIVELY; N = 6/GROUP), 5-HYDROXYMETHYLCYTOSINE LEVELS IN THE STAT3 PROMOTER (75 +/- 16.1 VS. 156 +/- 28.9; P = 0.0043; AND 91 +/- 19.1 VS. 156 +/- 28.9; P = 0.0066, RESPECTIVELY; N = 5/GROUP), AND CONSEQUENT STAT3 EXPRESSION (93 +/- 19.6 VS. 137 +/- 27.5; P = 0.035; AND 72 +/- 15.2 VS. 137 +/- 27.5; P = 0.0028, RESPECTIVELY; N = 5/GROUP) IN COMPLETE FREUND'S ADJUVANT-TREATED MICE. CONCLUSIONS: THIS STUDY REVEALS A NOVEL EPIGENETIC MECHANISM FOR TEN-ELEVEN TRANSLOCATION METHYLCYTOSINE DIOXYGENASE-1 AND TEN-ELEVEN TRANSLOCATION METHYLCYTOSINE DIOXYGENASE-3 IN THE MODULATION OF SPINAL NOCICEPTIVE INFORMATION VIA TARGETING OF STAT3. 2017 4 185 35 ACCUMULATION OF ABERRANT CPG HYPERMETHYLATION BY HELICOBACTER PYLORI INFECTION PROMOTES DEVELOPMENT AND PROGRESSION OF GASTRIC MALT LYMPHOMA. ABERRANT DNA HYPERMETHYLATION IS AN IMPORTANT MECHANISM FOR THE INACTIVATION OF TUMOR-RELATED GENES IN HUMAN TUMORS. GASTRIC MUCOSA-ASSOCIATED LYMPHOID TISSUE (MALT) LYMPHOMAS ARISE FROM HELICOBACTER PYLORI-ASSOCIATED CHRONIC GASTRITIS; MOST PATIENTS ARE H. PYLORI-POSITIVE AND ERADICATION THERAPY IS HIGHLY EFFECTIVE. IN THE PRESENT STUDY, WE USED METHYLATION-SPECIFIC PCR TO ANALYZE THE DNA METHYLATION STATUS OF 11 TUMOR-RELATED GENES (KIP2, P16, HMLH-1, P15, P73, MGMT, DAPK, MINT1, MINT2, MINT31 AND HCAD) IN 21 SPECIMENS OF MALT LYMPHOMA, 5 SPECIMENS OF MALT LYMPHOMA WITH LARGE CELL COMPONENT (HIGH-GRADE MALT LYMPHOMA), 15 SPECIMENS OF DIFFUSE LARGE B-CELL LYMPHOMA (DLBCL), 8 SPECIMENS OF COMPLETE REMISSION OF MALT LYMPHOMA AFTER ERADICATION THERAPY, 5 SPECIMENS WITH NO EVIDENCE OF MALIGNANCY AND PBMCS FROM 10 HEALTHY DONORS. THE AVERAGE NUMBER OF METHYLATED GENES WAS SIGNIFICANTLY GREATER IN GASTRIC LYMPHOMAS AS COMPARED TO NORMAL CONTROLS (P<0.001). THE CPG ISLAND METHYLATOR PHENOTYPE (CIMP) WAS OBSERVED IN 93.3% (14/15) OF DLBCLS, 100% (5/5) OF HIGH-GRADE MALT LYMPHOMAS AND 61.9% (13/21) OF MALT LYMPHOMAS; IN CONTRAST, CIMP WAS NOT FOUND IN THE CONTROL GROUP (0%). THE AVERAGE NUMBER OF METHYLATED GENES AND THE CIMP INCIDENCE SIGNIFICANTLY INCREASED WITH H. PYLORI INFECTION. FURTHERMORE, ABERRANT CPG METHYLATION OF SPECIFIC GENES, SUCH AS P16, MGMT AND MINT31, WAS CONSISTENTLY ASSOCIATED WITH H. PYLORI INFECTION. THESE FINDINGS STRONGLY SUGGEST THAT H. PYLORI INFECTION CAUSES THE ABERRANT DNA HYPERMETHYLATION OF SPECIFIC GENES AND INDUCES CIMP, WHICH IS AN IMPORTANT EPIGENETIC MECHANISM FOR THE DEVELOPMENT AND PROGRESSION OF GASTRIC MALT LYMPHOMA; ADDITIONALLY, OUR FINDINGS PROVIDE NEW EPIGENETIC MARKERS. 2009 5 867 32 CHRONIC ACTIVE EPSTEIN-BARR VIRUS INFECTION OF T/NK-CELL TYPE MIMICKING CLASSIC HODGKIN LYMPHOMA: CLINICOPATHOLOGIC AND GENETIC FEATURES OF 8 CASES SUPPORTING A VARIANT WITH "HODGKIN/REED-STERNBERG-LIKE" CELLS OF NK PHENOTYPE. CHRONIC ACTIVE EPSTEIN-BARR VIRUS (EBV) INFECTION OF T-CELL AND NK-CELL TYPE, SYSTEMIC FORM (CAEBV-T/NK-S) IS CHARACTERIZED BY EBV T-CELL AND/OR NK-CELL PROLIFERATION WITH NO CHANGES SUGGESTING MALIGNANCY. THEREFORE, WHEN HODGKIN/REED-STERNBERG (HRS)-LIKE CELLS ARE SCATTERED IN CAEBV-T/NK-S, IT IS MORE LIKELY TO BE MISDIAGNOSED AS CLASSIC HODGKIN LYMPHOMA. WE ENCOUNTERED A CASE WHEREIN THE PATIENT SHOWED HRS-LIKE CELLS WITH TYPICAL NK PHENOTYPE. THEREFORE, WE FURTHER INVESTIGATED 8 SIMILAR CASES TO PROVIDE CLINICOPATHOLOGIC AND GENETIC FEATURES AND DISCUSS THEIR DISTINCTION FROM OTHER RELATED DISEASES. CLINICALLY, ALL CASES MET THE DIAGNOSTIC CRITERIA OF CAEBV. MOREOVER, 4/8 PATIENTS HAD HEMOPHAGOCYTIC LYMPHOHISTIOCYTOSIS. THE MEDIAN SURVIVAL WAS 16 MONTHS (RANGE, 5 TO 35 MO). PATHOLOGICALLY, ALL LYMPH NODE SAMPLES HAD A REMARKABLY SIMILAR MORPHOLOGY WITH SCATTERED HRS-LIKE CELLS SURROUNDED BY A MIXTURE OF SMALL-SIZED LYMPHOCYTES, PLASMA CELLS, AND MACROPHAGES THAT MASQUERADED CLASSIC HODGKIN LYMPHOMA. BESIDES, ERYTHROPHAGOCYTOSIS WAS DETECTED IN 4/11 SAMPLES. THE HRS-LIKE CELLS WERE POSITIVE FOR CD2, CD3P, CD30, CD56, GRB, AND EBER-ISH, BUT NEGATIVE FOR CD20, CD5, PAX-5, AND LMP-1. THE SURROUNDING LYMPHOCYTES WERE MAINLY CD8 CYTOTOXIC T CELLS, WITHOUT OBVIOUS ABERRANT EXPRESSION. IN ADDITION, ALL PATIENTS WERE POLYCLONAL IN THE T-CELL RECEPTOR GAMMA REARRANGEMENT TEST. THE HARBORED MUTATIONS WERE MAINLY IN EPIGENETIC MODIFIERS, JAK-STAT SIGNALING PATHWAY, AND APOPTOSIS/CELL CYCLE PATHWAY, INCLUDING SOCS1, DDX3X, AND KMT2D, SIMILAR TO OTHER EBV-ASSOCIATED T/NK-CELL LYMPHOPROLIFERATIVE DISORDERS. THEREFORE, THE EVIDENCE INDICATES THAT "HRS-LIKE CELLS OF NK PHENOTYPE" IS A VARIANT OF CAEBV-T/NK-S. THIS STUDY MAY RAISE AWARENESS OF SUCH CONFOUNDING CAEBV-T/N-S CASES IN CLINICAL PRACTICE TO AVOID MISDIAGNOSIS AND TREATMENT DELAY. 2019 6 4432 24 MOLECULAR CHARACTERIZATION OF RICHTER SYNDROME IDENTIFIES DE NOVO DIFFUSE LARGE B-CELL LYMPHOMAS WITH POOR PROGNOSIS. RICHTER SYNDROME (RS) IS THE TRANSFORMATION OF CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) INTO AGGRESSIVE LYMPHOMA, MOST COMMONLY DIFFUSE LARGE B-CELL LYMPHOMA (DLBCL). WE CHARACTERIZE 58 PRIMARY HUMAN RS SAMPLES BY GENOME-WIDE DNA METHYLATION AND WHOLE-TRANSCRIPTOME PROFILING. OUR COMPREHENSIVE APPROACH DETERMINES RS DNA METHYLATION PROFILE AND UNRAVELS A CLL EPIGENETIC IMPRINT, ALLOWING CLL-RS CLONAL RELATIONSHIP ASSESSMENT WITHOUT THE NEED OF THE INITIAL CLL TUMOR DNA. DNA METHYLATION- AND TRANSCRIPTOMIC-BASED CLASSIFIERS WERE DEVELOPED, AND TESTING ON LANDMARK DLBCL DATASETS IDENTIFIES A POOR-PROGNOSIS, ACTIVATED B-CELL-LIKE DLBCL SUBSET IN 111/1772 SAMPLES. THE CLASSIFICATION ROBUSTLY IDENTIFIES PHENOTYPES VERY SIMILAR TO RS WITH A SPECIFIC GENOMIC PROFILE, ACCOUNTING FOR 4.3-8.3% OF DE NOVO DLBCLS. IN THIS WORK, RS MULTI-OMICS CHARACTERIZATION DETERMINES ONCOGENIC MECHANISMS, ESTABLISHES A SURROGATE MARKER FOR CLL-RS CLONAL RELATIONSHIP, AND PROVIDES A CLINICALLY RELEVANT CLASSIFIER FOR A SUBSET OF PRIMARY "RS-TYPE DLBCL" WITH UNFAVORABLE PROGNOSIS. 2023 7 2843 25 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 8 2391 23 EPIGENETIC REPRESSION OF DNA MISMATCH REPAIR BY INFLAMMATION AND HYPOXIA IN INFLAMMATORY BOWEL DISEASE-ASSOCIATED COLORECTAL CANCER. SPORADIC HUMAN MISMATCH REPAIR (MMR)-DEFICIENT COLORECTAL CANCERS ACCOUNT FOR APPROXIMATELY 12.5% OF ALL CASES OF COLORECTAL CANCER. MMR-DEFICIENT COLORECTAL CANCERS ARE CLASSICALLY CHARACTERIZED BY RIGHT-SIDED LOCATION, MULTIFOCALITY, MUCINOUS HISTOLOGY, AND LYMPHOCYTIC INFILTRATION. HOWEVER, TUMORS IN GERM-LINE MMR-DEFICIENT MOUSE MODELS LACK THESE HISTOPATHOLOGIC FEATURES. MICE LACKING THE HETEROTRIMERIC G PROTEIN ALPHA SUBUNIT GIALPHA2 DEVELOP CHRONIC COLITIS AND MULTIFOCAL, RIGHT-SIDED CANCERS WITH MUCINOUS HISTOPATHOLOGY, SIMILAR TO HUMAN MMR-DEFICIENT COLORECTAL CANCER. YOUNG GIALPHA2-/- COLONIC EPITHELIUM HAS NORMAL MMR EXPRESSION BUT SELECTIVELY LOSES MLH1 AND CONSEQUENTLY PMS2 EXPRESSION FOLLOWING INFLAMMATION. GIALPHA2-/- CANCERS HAVE MICROSATELLITE INSTABILITY. MLH1 IS EPIGENETICALLY SILENCED NOT BY PROMOTER HYPERMETHYLATION BUT BY DECREASED HISTONE ACETYLATION. CHRONICALLY INFLAMED GIALPHA2-/- COLONIC MUCOSA CONTAINS PATCHY HYPOXIA, WITH INCREASED CRYPT EXPRESSION OF THE HYPOXIA MARKERS DEC-1 AND BNIP3. CHROMATIN IMMUNOPRECIPITATION IDENTIFIED INCREASED BINDING OF THE TRANSCRIPTIONAL REPRESSOR DEC-1 TO THE PROXIMAL MLH1 PROMOTER IN HYPOXIC YAMC CELLS AND COLITIC GIALPHA2-/- CRYPTS. TREATING GIALPHA2-/- MICE WITH THE HISTONE DEACETYLASE INHIBITOR SUBEROYLANILIDE HYDROXAMIC ACID SIGNIFICANTLY DECREASED COLITIS ACTIVITY AND RESCUED MLH1 EXPRESSION IN CRYPT EPITHELIAL CELLS, WHICH WAS ASSOCIATED WITH INCREASED ACETYL HISTONE H3 LEVELS AND DECREASED DEC-1 BINDING AT THE PROXIMAL MLH1 PROMOTER, CONSISTENT WITH A HISTONE DEACETYLASE-DEPENDENT MECHANISM. THESE DATA LINK CHRONIC HYPOXIC INFLAMMATION, EPIGENETIC MMR PROTEIN DOWN-REGULATION, DEVELOPMENT OF MMR-DEFICIENT COLORECTAL CANCER, AND THE FIRSTMOUSE MODEL OF SOMATICALLY ACQUIRED MMR-DEFICIENT COLORECTAL CANCER. 2009 9 600 26 BETA-DEFENSINS AND ANALOGS IN HELICOBACTER PYLORI INFECTIONS: MRNA EXPRESSION LEVELS, DNA METHYLATION, AND ANTIBACTERIAL ACTIVITY. ANTIMICROBIAL PEPTIDES CAN PROTECT THE GASTRIC MUCOSA FROM BACTERIA, BUT HELICOBACTER PYLORI (H. PYLORI) CAN EQUALLY COLONIZE THE GASTRIC APPARATUS. TO UNDERSTAND BETA-DEFENSIN FUNCTION IN H. PYLORI-ASSOCIATED CHRONIC GASTRITIS, WE INVESTIGATED SUSCEPTIBILITY, HUMAN BETA-DEFENSIN MRNA EXPRESSION, AND DNA METHYLATION CHANGES TO PROMOTERS IN THE GASTRIC MUCOSA WITH OR WITHOUT H. PYLORI INFECTION. WE STUDIED THE EXPRESSION OF HBD2 (GENE NAME DEFB4A), HBD3 (DEFB103A), AND HBD4 (DEFB104) USING REAL-TIME PCR IN 15 CONTROL AND 10 H. PYLORI INFECTION PATIENT GASTRIC SPECIMENS. THIS STUDY DEMONSTRATES THAT H. PYLORI INFECTION IS RELATED TO GASTRIC ENHANCEMENT OF INDUCIBLE HBD2, BUT INDUCIBLE HBD3 AND HBD4 EXPRESSION LEVELS REMAINED UNCHANGED. HBD2 GENE METHYLATION LEVELS WERE OVERALL HIGHER IN H. PYLORI-NEGATIVE SAMPLES THAN IN H. PYLORI-POSITIVE SAMPLES. WE ALSO ASSESSED ANTIMICROBIAL SUSCEPTIBILITY USING GROWTH ON BLOOD AGAR. THE H. PYLORI STRAIN TOX+ WAS SUSCEPTIBLE TO ALL DEFENSINS TESTED AND THEIR ANALOGS (3N, 3NI). THESE RESULTS SHOW THAT HBD2 IS INVOLVED IN GASTRITIS DEVELOPMENT DRIVEN BY H. PYLORI, WHICH FACILITATES THE CREATION OF AN EPIGENETIC FIELD DURING H. PYLORI-ASSOCIATED GASTRIC TUMORIGENESIS. 2019 10 831 36 CHARACTERIZATION OF TET AND IDH GENE EXPRESSION IN CHRONIC LYMPHOCYTIC LEUKEMIA: COMPARISON WITH NORMAL B CELLS AND PROGNOSTIC SIGNIFICANCE. BACKGROUND: CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) IS THE MOST COMMON HEMATOLOGICAL MALIGNANCY IN WESTERN COUNTRIES, CHARACTERIZED BY A HETEROGENEOUS CLINICAL COURSE. ALTHOUGH GENETIC STUDIES HAVE IDENTIFIED CHROMOSOMAL ABERRATIONS OR SPECIFIC MUTATIONS, EPIGENETIC CHANGES HAVE BEEN POORLY CHARACTERIZED IN CLL. METHODS: WE ASSESSED TEN-ELEVEN TRANSLOCATIONS (TET) 1, 2, AND 3, ISOCITRATE DEHYDROGENASE (IDH) 1, AND 2 MESSENGER RNA (MRNA) EXPRESSION USING REAL-TIME PCR ON PURIFIED LEUKEMIC B CELLS FROM 214 CLL PATIENTS (MEDIAN FOLLOW-UP = 75 MONTHS, RANGE 1-380), NORMAL PERIPHERAL BLOOD B CELLS (N = 20), AND UMBILICAL CORD BLOOD B CELLS (N = 21). THE MICROENVIRONMENT INFLUENCE WAS ASSESSED AFTER 24 H CO-CULTURE OF CLL CELLS WITH BONE MARROW MESENCHYMAL STROMAL CELLS (BMSC). FINALLY, 5-HYDROXYMETHYLCYTOSINE LEVEL (%5-HMC) WAS ASSESSED BY ELISA IN CLL CELLS ALONE OR WITH MICROENVIRONMENT STIMULI. RESULTS: TET 1 AND 3 AND IDH2 WERE DECREASED IN CLL CELLS COMPARED WITH HEALTHY B CELLS (P = 0.0221, 0.0013, <0.0001, RESPECTIVELY), WHILE IDH1 WAS OVEREXPRESSED (P = 0.0037). TET2 AND IDH1 WERE SIGNIFICANTLY CORRELATED WITH TREATMENT-FREE SURVIVAL (TFS); PATIENTS WITH HIGH TET2/IDH1 EXPRESSION HAD A HIGHER MEDIAN TFS (111 MONTHS) THAN PATIENTS WITH LOW EXPRESSION (78 MONTHS, P = 0.0071/0.0123). MOREOVER, TET1 EXPRESSION DECREASED (P = 0.0371), WHILE TET3 AND IDH2 EXPRESSION INCREASED (P = 0.0273/0.0039) IN CO-CULTURES. HOWEVER, %5-HMC WAS NOT CORRELATED WITH CLINICAL DATA AND WAS UNCHANGED FOLLOWING MICROENVIRONMENT STIMULI. CONCLUSIONS: DESPITE A SLIGHT DEREGULATION IN CLL CELLS COMPARED WITH NORMAL B CELLS, WE IDENTIFIED A SIGNIFICANT ASSOCIATION BETWEEN TET/IDH GENE EXPRESSION AND PROGNOSIS, SUGGESTING THAT EPIGENETIC CHANGES COULD POTENTIALLY BE ASSOCIATED WITH DISEASE PROGRESSION. MOREOVER, DESPITE AN IDENTICAL %5-HMC, TET GENE EXPRESSION WAS INFLUENCED BY CONTACT WITH BMSC CONFIRMING THE CRUCIAL ROLE OF THE MICROENVIRONMENT IN CLL PATHOGENESIS. 2016 11 3805 21 INTESTINE-SPECIFIC HOMEOBOX (ISX) INDUCES INTESTINAL METAPLASIA AND CELL PROLIFERATION TO CONTRIBUTE TO GASTRIC CARCINOGENESIS. BACKGROUND: HELICOBACTER PYLORI INDUCES CHRONIC INFLAMMATION AND INTESTINAL METAPLASIA (IM) THROUGH GENETIC AND EPIGENETIC CHANGES AND ACTIVATION OF INTRACELLULAR SIGNALING PATHWAYS THAT CONTRIBUTE TO GASTRIC CARCINOGENESIS. HOWEVER, THE PRECISE MECHANISM OF IM IN GASTRIC CARCINOGENESIS HAS NOT BEEN FULLY ELUCIDATED. WE PREVIOUSLY FOUND THAT INTESTINE-SPECIFIC HOMEOBOX (ISX) MRNA EXPRESSION INCREASED IN ORGANOIDS CULTURED FROM HELICOBACTER-INFECTED MOUSE MUCOSA. IN THIS STUDY, WE ELUCIDATE THE ROLE OF ISX IN THE DEVELOPMENT OF IM AND GASTRIC CARCINOGENESIS. METHODS: ISX EXPRESSION WAS ASSESSED IN HELICOBACTER-INFECTED MOUSE AND HUMAN GASTRIC MUCOSA. MKN45 GASTRIC CANCER CELLS WERE CO-CULTURED WITH H. PYLORI TO DETERMINE WHETHER HELICOBACTER INFECTION INDUCED ISX EXPRESSION. WE ESTABLISHED STABLE MKN45 TRANSFECTED CELLS EXPRESSING ISX (STABLE-ISX MKN45) AND PERFORMED A SPHEROID COLONY FORMATION ASSAY AND A XENOGRAFT MODEL. WE PERFORMED ISX IMMUNOHISTOCHEMISTRY IN CANCER AND ADJACENT GASTRIC TISSUES. RESULTS: ISX EXPRESSION WAS INCREASED IN MOUSE AND HUMAN GASTRIC MUCOSA INFECTED WITH HELICOBACTER. THE PRESENCE OF IM AND H. PYLORI INFECTION IN HUMAN STOMACH WAS CORRELATED WITH ISX EXPRESSION. H. PYLORI INDUCED ISX MRNA AND PROTEIN EXPRESSION. CDX1/2, CYCLIND1, AND MUC2 WERE UPREGULATED IN STABLE-ISX MKN45, WHEREAS MUC5AC WAS DOWNREGULATED. STABLE-ISX MKN45 CELLS FORMED MORE SPHEROID COLONIES, AND HAD HIGH TUMORIGENIC ABILITY. ISX EXPRESSION IN GASTRIC CANCER AND ADJACENT MUCOSA WERE CORRELATED. CONCLUSIONS: ISX EXPRESSION INDUCED BY H. PYLORI INFECTION MAY LEAD TO IM AND HYPERPROLIFERATION OF GASTRIC MUCOSA THROUGH CDX1/2 AND CYCLIND1 EXPRESSION, CONTRIBUTING TO GASTRIC CARCINOGENESIS. 2016 12 4102 24 MDR1-P-GLYCOPROTEIN BEHAVES AS AN ONCOFETAL PROTEIN THAT PROMOTES CELL SURVIVAL IN GASTRIC CANCER CELLS. P-GLYCOPROTEIN (P-GP), TRADITIONALLY LINKED TO CANCER POOR PROGNOSIS AND MULTIDRUG RESISTANCE, IS UNDETECTABLE IN NORMAL GASTRIC MUCOSA AND OVEREXPRESSED IN GASTRIC CANCER (GC). WE PROPOSE THAT P-GP MAY BE INVOLVED IN HELICOBACTER PYLORI (HP)-RELATED GASTRIC CARCINOGENESIS BY INHIBITING APOPTOSIS. AIM OF THE STUDY WAS TO EVALUATE THE EXPRESSION OF P-GP IN FETAL STOMACH AND IN HP-RELATED GASTRIC CARCINOGENESIS, THE EPIGENETIC CONTROL OF THE MULTI-DRUG RESISTANCE-1 (MDR1) GENE, THE LOCALIZATION AND INTERACTION BETWEEN P-GP AND BCL-X(L) AND THE EFFECT OF THE SELECTIVE SILENCING OF P-GP ON CELL SURVIVAL. P-GP AND BCL-XL EXPRESSION WAS EVALUATED BY IMMUNOHISTOCHEMISTRY ON 28 SPONTANEOUSLY ABORTIVE HUMAN FETUSES, 66 HP-NEGATIVE SUBJECTS, 138 HP-POSITIVE CHRONIC GASTRITIS (CG) OF WHOM 28 WITH INTESTINAL METAPLASIA (IM) AND 45 INTESTINAL TYPE GCS. P-GP/BCL-X(L) COLOCALIZATION WAS INVESTIGATED BY CONFOCAL IMMUNOFLUORESCENCE MICROSCOPY AND PROTEIN-PROTEIN INTERACTION BY CO-IMMUNOPRECIPITATION, IN BASAL CONDITIONS AND AFTER STRESS-INDUCED APOPTOSIS, IN GC CELL LINES AGS AND MKN-28 AND HEPATOCELLULAR CARCINOMA CELL LINE HEP-G2. THE ROLE OF P-GP IN CONTROLLING APOPTOSIS WAS EVALUATED BY KNOCKING DOWN ITS EXPRESSION WITH A SPECIFIC SMALL INTERFERING RNAS IN STRESSED AGS AND MKN-28 CELL LINES. P-GP IS EXPRESSED IN THE GASTRIC MUCOSA OF ALL HUMAN FETUSES WHILE, IT IS UNDETECTABLE IN ADULT NORMAL MUCOSA AND RE-EXPRESSED IN 30/110 HP-POSITIVE NON-IM-CG, 28/28 IM-CG AND 40/45 GCS. P-GP EXPRESSION DIRECTLY CORRELATES WITH THAT OF BCL-X(L) AND WITH THE PROMOTER HYPOMETHYLATION OF THE MDR1 GENE. IN GC CELL LINES, P-GP IS LOCALIZED ON THE PLASMA MEMBRANE AND MITOCHONDRIA WHERE IT COLOCALIZES WITH BCL-X(L). CO-IMMUNOPRECIPITATION CONFIRMS THE PHYSICAL INTERACTION BETWEEN P-GP AND BCL-X(L) IN AGS, MKN-28 AND HEP-G2, AT BOTH BASAL LEVEL AND AFTER STRESS-INDUCED APOPTOSIS. THE SELECTIVE SILENCING OF P-GP SENSITIZES GC CELLS TO STRESS-INDUCED APOPTOSIS. P-GP BEHAVES AS AN ONCOFETAL PROTEIN THAT, BY CROSS-TALKING WITH BCL-X(L), ACTS AS AN ANTI-APOPTOTIC AGENT IN HP-RELATED GASTRIC CARCINOGENESIS. 2012 13 5984 33 TET2, DNMT3A, IDH1, AND JAK2 MUTATION IN MYELOPROLIFERATIVE NEOPLASMS IN SOUTHERN IRAN. BACKGROUND: FIVE EPIGENETIC REGULATOR MUTATIONS ARE CONSIDERED IN MYELOPROLIFERATIVE NEOPLASMS (MPN) THAT HAVE PROGNOSTIC AND THERAPEUTIC VALUES. OBJECTIVE: WE AIMED TO EVALUATE THESE MUTATIONS IN MPNS AMONG THE IRANIAN POPULATION. METHODS: WE SELECTED 5 MUTATIONS IN 4 EPIGENETIC REGULATORY GENES [TET2, DNMT3A, IDH1 (RS147001633&RS121913499), AND JAK2)] AND EVALUATED 130 PATIENTS WITH MPNS INCLUDING 78 PHILADELPHIA CHROMOSOME NEGATIVE (49 ETS, 20 PVS, AND 9 PMFS) AND 52 PHILADELPHIA CHROMOSOME-POSITIVE PATIENTS AS WELL AS 51 HEALTHY CONTROLS. RESULTS: EIGHT PATIENTS (6.5%) CARRIED THE DNMT3A MUTATION, 35 (27%) WERE POSITIVE FOR TET2 MUTATION AND 64 (49.3%) HAD THE JAK2V617F MUTATION. IN THE HEALTHY CONTROLS, 16 (31.4%) CASES HAD THE TET2 MUTATION (15 HETEROZYGOTE + 1 HOMOZYGOTE) AND ONE HAD HETEROZYGOTE JAK2 MUTATION. THERE WAS NO STATISTICALLY SIGNIFICANT DIFFERENCE BETWEEN PATIENT GROUPS FOR ANY OF THESE MUTATIONS, EXCEPT FOR JAK2. THE JAK2 MUTATION RATE WAS 18 (90%), 25 (51%), 7 (77.8%), 14 (26.9%) IN POLYCYTHEMIA VERA, ESSENTIAL THROMBOCYTHEMIA, PRIMARY MYELOFIBROSIS, AND CHRONIC MYELOCYTIC LEUKEMIA, RESPECTIVELY. PATIENTS AGED 60 AND OLDER WERE MORE LIKELY TO CARRY THE TET2 MUTATION (23% VS. 39% IN YOUNGER AND OLDER THAN 60 YEARS OLD INDIVIDUALS, P=0.025). IDH1 WAS NOT DETECTED AT ALL AND PV HAD THE HIGHEST TET2 MUTATION 7(35%). TWO PMF PATIENTS HAD A HISTORY OF BONE MARROW TRANSPLANTATION THAT WERE NEGATIVE FOR IDH1AND DNMT3A AND ONE WAS POSITIVE FOR TET2 MUTATION. CONCLUSION: IN THE NORMAL IRANIAN POPULATION, THE HETEROZYGOTE FORM OF TET2 MUTATION IS SIGNIFICANT, ESPECIALLY IN THE ELDERLY. NO ASSOCIATION WAS FOUND BETWEEN JAK2 AND TET2 MUTATIONS. BOTH OF THEM ARE MORE PREVALENT IN THE AGE GROUP OF 60 YEARS AND OLDER. DNMT3A MUTATION HAS A LOW PREVALENCE AND OCCURS IN BOTH POSITIVE AND NEGATIVE MPNS. 2021 14 6248 27 THE METHYLATION STATUS OF THE DDX43 PROMOTER IN CHINESE PATIENTS WITH CHRONIC MYELOID LEUKEMIA. ABERRANT DNA METHYLATION IS A COMMON EPIGENETIC ALTERATION AND AN IMPORTANT FEATURE IN HUMAN CANCERS. THE DEAD BOX POLYPEPTIDE 43 (DDX43) HAS BEEN FOUND TO BE OVEREXPRESSED IN VARIOUS SOLID TUMORS AND SOME HEMATOLOGIC MALIGNANCIES. IN THE PRESENT STUDY, WE INVESTIGATED THE METHYLATION STATUS OF THE DDX43 PROMOTER IN 87 CHINESE PATIENTS WITH CHRONIC MYELOID LEUKEMIA (CML) USING REAL-TIME QUANTITATIVE METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION AND EXAMINED THE DDX43 TRANSCRIPT IN 35 PATIENTS USING REAL-TIME QUANTITATIVE POLYMERASE CHAIN REACTION. DDX43 PROMOTER HYPOMETHYLATION WAS OBSERVED IN 22 (25.3%) CML PATIENTS. NO SIGNIFICANT CORRELATION WAS FOUND BETWEEN THE HYPOMETHYLATION OF THE DDX43 PROMOTER WITH THE AGE, SEX, WHITE BLOOD CELL COUNTS, HEMOGLOBIN CONCENTRATION, PLATELET COUNTS, AND CHROMOSOMAL ABNORMALITIES OF CML PATIENTS (P>0.05). THE FREQUENCY OF DDX43 HYPOMETHYLATION IN PATIENTS IN THE CHRONIC PHASE, IN THE ACCELERATED PHASE, AND IN BLAST CRISIS WAS 23.4% (15/64), 25.0% (2/8), AND 33.3% (5/15), RESPECTIVELY (P>0.05). THERE WAS A SIGNIFICANT CORRELATION BETWEEN DDX43 HYPOMETHYLATION AND DDX43 TRANSCRIPT (R=0.469, P=0.004). OUR DATA SUGGEST THAT HYPOMETHYLATION OF THE DDX43 PROMOTER MAY BE AN EARLY AND FREQUENT MOLECULAR EVENT IN THE DEVELOPMENT OF CML IN CHINESE PATIENTS. 2013 15 1693 28 DUSP4 DEFICIENCY CAUSED BY PROMOTER HYPERMETHYLATION DRIVES JNK SIGNALING AND TUMOR CELL SURVIVAL IN DIFFUSE LARGE B CELL LYMPHOMA. THE EPIGENETIC DYSREGULATION OF TUMOR SUPPRESSOR GENES IS AN IMPORTANT DRIVER OF HUMAN CARCINOGENESIS. WE HAVE COMBINED GENOME-WIDE DNA METHYLATION ANALYSES AND GENE EXPRESSION PROFILING AFTER PHARMACOLOGICAL DNA DEMETHYLATION WITH FUNCTIONAL SCREENING TO IDENTIFY NOVEL TUMOR SUPPRESSORS IN DIFFUSE LARGE B CELL LYMPHOMA (DLBCL). WE FIND THAT A CPG ISLAND IN THE PROMOTER OF THE DUAL-SPECIFICITY PHOSPHATASE DUSP4 IS ABERRANTLY METHYLATED IN NODAL AND EXTRANODAL DLBCL, IRRESPECTIVE OF ABC OR GCB SUBTYPE, RESULTING IN LOSS OF DUSP4 EXPRESSION IN 75% OF >200 EXAMINED CASES. THE DUSP4 GENOMIC LOCUS IS FURTHER DELETED IN UP TO 13% OF AGGRESSIVE B CELL LYMPHOMAS, AND THE LACK OF DUSP4 IS A NEGATIVE PROGNOSTIC FACTOR IN THREE INDEPENDENT COHORTS OF DLBCL PATIENTS. ECTOPIC EXPRESSION OF WILD-TYPE DUSP4, BUT NOT OF A PHOSPHATASE-DEFICIENT MUTANT, DEPHOSPHORYLATES C-JUN N-TERMINAL KINASE (JNK) AND INDUCES APOPTOSIS IN DLBCL CELLS. PHARMACOLOGICAL OR DOMINANT-NEGATIVE JNK INHIBITION RESTRICTS DLBCL SURVIVAL IN VITRO AND IN VIVO AND SYNERGIZES STRONGLY WITH THE BRUTON'S TYROSINE KINASE INHIBITOR IBRUTINIB. OUR RESULTS INDICATE THAT DLBCL CELLS DEPEND ON JNK SIGNALING FOR SURVIVAL. THIS FINDING PROVIDES A MECHANISTIC BASIS FOR THE CLINICAL DEVELOPMENT OF JNK INHIBITORS IN DLBCL, IDEALLY IN SYNTHETIC LETHAL COMBINATIONS WITH INHIBITORS OF CHRONIC ACTIVE B CELL RECEPTOR SIGNALING. 2015 16 4549 31 MUTATION ANALYSIS OF THERAPY-RELATED MYELOID NEOPLASMS. WE ANALYZED THE GENETIC MUTATION STATUS OF 13 PATIENTS WITH THERAPY-RELATED MYELOID NEOPLASMS (T-MN). CONSISTENT WITH PREVIOUS REPORTS, T-MN CELLS PREFERENTIALLY ACQUIRED MUTATIONS IN TP53 AND EPIGENETIC MODIFYING GENES, INSTEAD OF MUTATIONS IN TYROSINE KINASE AND SPLICEOSOME GENES. FURTHERMORE, WE COMPARED THE MUTATION STATUS OF THREE T-MN CELLS WITH EACH OF THE INITIAL LYMPHOID MALIGNANT CELLS, AND IDENTIFIED COMMON MUTATIONS AMONG T-MN AND THE INITIAL MALIGNANT CELLS IN TWO PATIENTS. IN A PATIENT WHO DEVELOPED CHRONIC MYELOMONOCYTIC LEUKEMIA (CMML) AFTER FOLLICULAR LYMPHOMA (FL), TET2 MUTATION WAS IDENTIFIED IN BOTH CMML AND FL CELLS. NOTABLY, THE TET2 MUTATION WAS ALSO IDENTIFIED IN PERIPHERAL BLOOD CELLS IN THE DISEASE-FREE PERIOD WITH THE SAME ALLELIC FREQUENCY AS CMML AND FL CELLS, BUT NOT IN A GERM-LINE CONTROL, INDICATING THAT THE TET2 MUTATION OCCURRED SOMATICALLY IN THE INITIATING CLONE FOR BOTH MALIGNANT CELLS. ON THE OTHER HAND, A GERM-LINE MYB MUTATION WAS IDENTIFIED IN A PATIENT WHO DEVELOPED MYELODYSPLASTIC SYNDROMES (MDS) AFTER FL. THESE RESULTS SUGGEST THAT GERM-LINE DEPOSITION AND CLONAL HEMATOPOIESIS ARE CLOSELY ASSOCIATED WITH T-MN SUSCEPTIBILITY; HOWEVER, FURTHER ANALYSIS IS NECESSARY TO CLARIFY THE MECHANISM REQUIRED TO PROVIDE THE INITIATING CLONE WITH LINEAGE COMMITMENT AND CLONAL EXPANSION. 2018 17 3231 23 HELICOBACTER PYLORI-INDUCED MODULATION OF THE PROMOTER METHYLATION OF WNT ANTAGONIST GENES IN GASTRIC CARCINOGENESIS. BACKGROUND: THIS STUDY AIMED TO INVESTIGATE THE CHANGES IN THE PROMOTER METHYLATION AND GENE EXPRESSION OF MULTIPLE WNT ANTAGONISTS BETWEEN THE CHRONIC INFECTION AND ERADICATION OF HELICOBACTER PYLORI (H. PYLORI) IN GASTRIC CARCINOGENESIS. METHODS: THE LEVELS OF METHYLATION AND CORRESPONDING MRNA EXPRESSION OF SEVEN WNT ANTAGONIST GENES (SFRP1, -2, -5, DKK1, -2, -3, WIF1) WERE COMPARED AMONG THE PATIENTS WITH H. PYLORI-POSITIVE GASTRIC CANCERS (GCS), AND H. PYLORI-POSITIVE AND H. PYLORI-NEGATIVE CONTROLS, BY QUANTITATIVE METHYLIGHT ASSAY AND REAL-TIME REVERSE TRANSCRIPTION (RT)-POLYMERASE CHAIN REACTION (PCR), RESPECTIVELY. THE CHANGES OF THE METHYLATION AND EXPRESSION LEVELS OF THE GENES WERE ALSO COMPARED BETWEEN THE H. PYLORI ERADICATION AND H. PYLORI-PERSISTENT GROUPS 1 YEAR AFTER ENDOSCOPIC RESECTION OF GCS. RESULTS: THE METHYLATION LEVELS OF SFRP AND DKK FAMILY GENES WERE SIGNIFICANTLY INCREASED IN THE PATIENTS WITH H. PYLORI-POSITIVE GCS AND FOLLOWED BY H. PYLORI-POSITIVE CONTROLS COMPARED WITH H. PYLORI-NEGATIVE CONTROLS (P < 0.001). SFRP1, -2, AND DKK3 GENE EXPRESSION WAS STEPWISE DOWNREGULATED FROM H. PYLORI-NEGATIVE CONTROLS, H. PYLORI-POSITIVE CONTROLS, AND TO H. PYLORI-POSITIVE GCS (P < 0.05). AMONG THE WNT ANTAGONISTS, ONLY THE DEGREES OF METHYLATION AND DOWNREGULATION OF DKK3 WERE SIGNIFICANTLY REDUCED AFTER H. PYLORI ERADICATION (P < 0.05). CONCLUSION: EPIGENETIC SILENCING OF SFRP AND DKK FAMILY GENES MAY FACILITATE THE FORMATION OF AN EPIGENETIC FIELD DURING H. PYLORI-ASSOCIATED GASTRIC CARCINOGENESIS. THE EPIGENETIC FIELD MAY NOT BE REVERSED EVEN AFTER H. PYLORI ERADICATION EXCEPT BY DKK3 METHYLATION. 2018 18 4984 20 PATHWAYS OF GASTRIC CARCINOGENESIS, HELICOBACTER PYLORI VIRULENCE AND INTERACTIONS WITH ANTIOXIDANT SYSTEMS, VITAMIN C AND PHYTOCHEMICALS. HELICOBACTER PYLORI IS A CLASS ONE CARCINOGEN WHICH CAUSES CHRONIC ATROPHIC GASTRITIS, GASTRIC INTESTINAL METAPLASIA, DYSPLASIA AND ADENOCARCINOMA. THE MECHANISMS BY WHICH H. PYLORI INTERACTS WITH OTHER RISK AND PROTECTIVE FACTORS, PARTICULARLY VITAMIN C IN GASTRIC CARCINOGENESIS ARE COMPLEX. GASTRIC CARCINOGENESIS INCLUDES METABOLIC, ENVIRONMENTAL, EPIGENETIC, GENOMIC, INFECTIVE, INFLAMMATORY AND ONCOGENIC PATHWAYS. THE MOLECULAR CLASSIFICATION OF GASTRIC CANCER SUBTYPES HAS REVOLUTIONIZED THE UNDERSTANDING OF GASTRIC CARCINOGENESIS. THIS INCLUDES THE TUMOUR MICROENVIRONMENT, GERMLINE MUTATIONS, AND THE ROLE OF HELICOBACTER PYLORI BACTERIA, EPSTEIN BARR VIRUS AND EPIGENETICS IN SOMATIC MUTATIONS. THERE IS EVIDENCE THAT ASCORBIC ACID, PHYTOCHEMICALS AND ENDOGENOUS ANTIOXIDANT SYSTEMS CAN MODIFY THE RISK OF GASTRIC CANCER. GASTRIC JUICE ASCORBATE LEVELS DEPEND ON DIETARY INTAKE OF ASCORBIC ACID BUT CAN ALSO BE DECREASED BY H. PYLORI INFECTION, H. PYLORI CAGA SECRETION, TOBACCO SMOKING, ACHLORHYDRIA AND CHRONIC ATROPHIC GASTRITIS. ASCORBIC ACID MAY BE PROTECTIVE AGAINST GASTRIC CANCER BY ITS ANTIOXIDANT EFFECT IN GASTRIC CYTOPROTECTION, REGENERATING ACTIVE VITAMIN E AND GLUTATHIONE, INHIBITING ENDOGENOUS N-NITROSATION, REDUCING TOXIC EFFECTS OF INGESTED NITROSODIMETHYLAMINES AND HETEROCYCLIC AMINES, AND PREVENTING H. PYLORI INFECTION. THE EFFECTIVENESS OF SUCH CYTOPROTECTION IS RELATED TO H. PYLORI STRAIN VIRULENCE, PARTICULARLY CAGA EXPRESSION. THE ROLE OF VITAMIN C IN EPIGENETIC REPROGRAMMING IN GASTRIC CANCER IS STILL EVOLVING. OTHER FACTORS IN CONJUNCTION WITH VITAMIN C ALSO PLAY A ROLE IN GASTRIC CARCINOGENESIS. ERADICATION OF H. PYLORI MAY LEAD TO RECOVERY OF VITAMIN C SECRETION BY GASTRIC EPITHELIUM AND ENABLE REGRESSION OF PREMALIGNANT GASTRIC LESIONS, THEREBY INTERRUPTING THE CORREA CASCADE OF GASTRIC CARCINOGENESIS. 2020 19 672 31 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 20 6593 24 TUMOR-ASSOCIATED MACROPHAGES PROMOTE EPIGENETIC SILENCING OF GELSOLIN THROUGH DNA METHYLTRANSFERASE 1 IN GASTRIC CANCER CELLS. EPIGENETIC REPRESSION OF THE TUMOR SUPPRESSOR GELSOLIN (GSN) IS FREQUENTLY OBSERVED IN CANCERS. CHRONIC INFLAMMATION CAN PROMOTE TUMOR PROGRESSION VIA ABERRANT DNA METHYLATION. IN THIS STUDY, WE INVESTIGATED THE ROLE OF TUMOR-ASSOCIATED MACROPHAGES (TAMS) IN DNA METHYLATION OF THE GSN GENE DURING GASTRIC CANCER PROGRESSION. IMMUNOFLUORESCENCE STAINING OF 121 GASTRIC CANCER TISSUES SHOWED ABERRANT LOCALIZATION OF GSN AND DNA METHYLTRANSFERASE 1 (DNMT1) AND JUXTAPOSITION OF DNMT1 AND M2 TAMS. DECREASED GSN PROTEIN AND MRNA EXPRESSION AND INCREASED DNA METHYLATION IN THE GSN PROMOTER WERE OBSERVED IN GASTRIC CANCER CELL LINES AND CLINICAL SPECIMENS. TO EXAMINE THE EFFECT OF TAMS ON DNA METHYLATION IN GASTRIC CANCER CELLS, WE PERFORMED IN VITRO COCULTURE ASSAYS AND FOUND INCREASED DNMT1 EXPRESSION BUT DECREASED GSN EXPRESSION IN GASTRIC CANCER CELLS AFTER COCULTURE WITH U937 CELLS. KNOCKDOWN OF DNMT1 EXPRESSION IN GASTRIC CANCER CELLS COULD ABORT U937 COCULTURE-MEDIATED GSN DOWNREGULATION. MEANWHILE, CCL5 WAS THE MAIN CHEMOKINE UPREGULATED IN COCULTURE MEDIUM. TREATMENT WITH CCL5 COULD INDUCE DNMT1 EXPRESSION IN GASTRIC CANCER CELLS VIA STAT3 SIGNALING. INHIBITING DNMT1 ACTIVITY WITH PROCAINAMIDE, INHIBITING DNA METHYLATION WITH 5-AZA, OR INHIBITING CCL5/CCR5 SIGNALING WITH MARAVIROC REDUCED TUMOR GROWTH IN VIVO IN CONCLUSION, UPREGULATION OF DNMT1 BY CCL5/CCR5/STAT3 SIGNALING IS CRITICAL FOR TAM-MEDIATED GSN SILENCING IN GASTRIC CANCER. THIS STUDY IDENTIFIED POTENTIAL TARGETS FOR GASTRIC CANCER THERAPY. CANCER IMMUNOL RES; 5(10); 885-97. (C)2017 AACR. 2017