1 3805 109 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 2 1950 41 EPIGENETIC ACTIVATION OF TENSIN 4 PROMOTES GASTRIC CANCER PROGRESSION. GASTRIC CANCER (GC) IS A COMPLEX DISEASE INFLUENCED BY MULTIPLE GENETIC AND EPIGENETIC FACTORS. CHRONIC INFLAMMATION CAUSED BY HELICOBACTER PYLORI INFECTION AND DIETARY RISK FACTORS CAN RESULT IN THE ACCUMULATION OF ABERRANT DNA METHYLATION IN GASTRIC MUCOSA, WHICH PROMOTES GC DEVELOPMENT. TENSIN 4 (TNS4), A MEMBER OF THE TENSIN FAMILY OF PROTEINS, IS LOCALIZED TO FOCAL ADHESION SITES, WHICH CONNECT THE EXTRACELLULAR MATRIX AND CYTOSKELETAL NETWORK. WE IDENTIFIED UPREGULATION OF TNS4 IN GC USING QUANTITATIVE REVERSE TRANSCRIPTION PCR WITH 174 PAIRED SAMPLES OF GC TUMORS AND ADJACENT NORMAL TISSUES. TRANSCRIPTIONAL ACTIVATION OF TNS4 OCCURRED EVEN DURING THE EARLY STAGE OF TUMOR DEVELOPMENT. TNS4 DEPLETION IN GC CELL LINES THAT EXPRESSED HIGH TO MODERATE LEVELS OF TNS4, I.E., SNU-601, KATO III, AND MKN74, REDUCED CELL PROLIFERATION AND MIGRATION, WHEREAS ECTOPIC EXPRESSION OF TNS4 IN THOSE LINES THAT EXPRESSED LOWER LEVELS OF TNS4, I.E., SNU-638, MKN1, AND MKN45 INCREASED COLONY FORMATION AND CELL MIGRATION. THE PROMOTER REGION OF TNS4 WAS HYPOMETHYLATED IN GC CELL LINES THAT SHOWED UPREGULATION OF TNS4. WE ALSO FOUND A SIGNIFICANT NEGATIVE CORRELATION BETWEEN TNS4 EXPRESSION AND CPG METHYLATION IN 250 GC TUMORS BASED ON THE CANCER GENOME ATLAS (TCGA) DATA. THIS STUDY ELUCIDATES THE EPIGENETIC MECHANISM OF TNS4 ACTIVATION AND FUNCTIONAL ROLES OF TNS4 IN GC DEVELOPMENT AND PROGRESSION AND SUGGESTS A POSSIBLE APPROACH FOR FUTURE GC TREATMENTS. 2023 3 600 30 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 4 6593 32 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 5 3718 39 INHIBITION OF BCL6B PROMOTES GASTRIC CANCER BY AMPLIFYING INFLAMMATION IN MICE. BACKGROUND: CHRONIC GASTRITIS HAS BEEN DEMONSTRATED TO BE A KEY CAUSE OF GASTRIC CANCER (GC), AND CONTROL OF GASTRIC INFLAMMATION IS REGARDED AS AN EFFECTIVE TREATMENT FOR THE CLINICAL PREVENTION OF GASTRIC CARCINOGENESIS. HOWEVER, THERE REMAINS AN UNMET NEED TO IDENTIFY THE DOMINANT REGULATORS OF GASTRIC ONCOGENESIS-ASSOCIATED INFLAMMATION IN VIVO. METHODS: THE MOUSE MODEL FOR THE STUDY OF INFLAMMATION-ASSOCIATED GC WAS INDUCED BY BENZO[A]PYRENE (BAP) INTRAGASTRIC ADMINISTRATION IN BCL6B(-/-) AND WILDTYPE MICE ON A C57BL/6 BACKGROUND. 5-AZA-2'-DEOXYCYTIDINE (5-AZA), THE DEMETHYLATION DRUG, WAS INTRAPERITONEALLY INJECTED TO RESTORE BCL6B EXPRESSION. HUMAN GC TISSUE ARRAY WAS USED TO ANALYSE PATIENT SURVIVAL BASED ON BCL6B AND CD3 PROTEIN EXPRESSION. RESULTS: BCL6B WAS GRADUALLY DOWNREGULATED BY ITS OWN PROMOTER HYPERMETHYLATION IN PARALLEL TO AN INCREASING INFLAMMATORY RESPONSE DURING THE PROGRESSION OF BAP-INDUCED GASTRIC CARCINOGENESIS IN MICE. MOREOVER, KNOCKOUT OF BCL6B DRAMATICALLY WORSENED THE SEVERITY OF GASTRIC CANCER AND AGGRAVATED THE INFLAMMATORY RESPONSE IN THE BAP-INDUCED MICE GC MODEL. RE-ACTIVATION OF BCL6B BY 5-AZA IMPEDED INFLAMMATORY AMPLIFICATION AND BAP-INDUCED GC DEVELOPMENT, PROLONGING SURVIVAL TIME IN WILDTYPE MICE, WHEREAS NO NOTABLE CURATIVE EFFECT OCCURRED IN BCL6B(-/-) MICE WITH 5-AZA TREATMENT. FINALLY, SIGNIFICANT NEGATIVE CORRELATIONS WERE DETECTED BETWEEN THE MRNA LEVELS OF BCL6B AND INFLAMMATORY CYTOKINES IN HUMAN GC TISSUES; PATIENTS HARBOURING BCL6B-NEGETIVE AND SEVERE-INFLAMMATION GC TUMOURS WERE FOUND TO EXHIBIT THE SHORTEST SURVIVAL TIME. CONCLUSIONS: EPIGENETIC INACTIVATION OF BCL6B PROMOTES GASTRIC CANCER THROUGH AMPLIFICATION OF THE GASTRIC INFLAMMATORY RESPONSE IN VIVO AND OFFERS A NEW APPROACH FOR GC TREATMENT AND REGENERATIVE MEDICINE. 2019 6 1067 27 CLINICAL UTILITY OF PDSS2 EXPRESSION TO STRATIFY PATIENTS AT RISK FOR RECURRENCE OF HEPATOCELLULAR CARCINOMA. IDENTIFICATION OF NOVEL GENETIC AND EPIGENETIC ALTERATIONS IS REQUIRED FOR OPTIMAL STRATIFICATION OF PATIENTS WITH HEPATOCELLULAR CARCINOMA (HCC) AT RISK FOR RECURRENCE AND ADVERSE PROGNOSIS. COENZYME Q10 (COQ10), WHICH MEDIATES APOPTOSIS, IS SYNTHESIZED BY PRENYL DIPHOSPHATE SYNTHASE SUBUNIT 2 (PDSS2). IN THE PRESENT STUDY WE EVALUATED THE CLINICAL SIGNIFICANCE AND REGULATORY MECHANISMS OF PDSS2 EXPRESSION IN HCC. PDSS2 EXPRESSION LEVELS AND THOSE OF GENES ENCODING POTENTIALLY INTERACTING PROTEINS AS WELL AS THE METHYLATION STATUS OF THE PDSS2 PROMOTER REGION WERE ANALYZED IN HCC CELL LINES. PDSS2 MRNA LEVELS IN 151 PAIRS OF RESECTED SPECIMENS WERE DETERMINED TO EVALUATE THE ASSOCIATION OF PDSS2 EXPRESSION AND CLINICOPATHOLOGICAL FACTORS. THE EXPRESSION AND DISTRIBUTION OF PDSS2 WERE DETERMINED USING IMMUNOHISTOCHEMISTRY. PDSS2 MRNA EXPRESSION WAS DECREASED IN SIX OF NINE HCC CELL LINES AND SIGNIFICANTLY CORRELATED WITH THOSE OF HEPATOCYTE NUCLEAR FACTOR 4ALPHA. PDSS2 TRANSCRIPTION IN HCC CELLS WITH DECREASED PDSS2 EXPRESSION ACCOMPANYING HYPERMETHYLATION WAS REACTIVATED AFTER TREATING THESE CELLS WITH A METHYLATION INHIBITOR. MEAN EXPRESSION LEVELS OF PDSS2 MRNA RELATIVE TO THAT OF UNINVOLVED LIVER DIMINISHED GRADUALLY IN THE ORDER OF CHRONIC HEPATITIS TO CIRRHOSIS, AND EACH WAS SIGNIFICANTLY HIGHER THAN THOSE OF HCCS. PDSS2 AND PDSS2 MRNA LEVELS WERE CONSISTENT. DECREASED PDSS2 MRNA LEVELS WERE DETECTED IN HCC TISSUES OF 56 PATIENTS, CORRELATED WITH SHORTER DISEASE-SPECIFIC SURVIVAL, AND WAS IDENTIFIED AS AN INDEPENDENT PROGNOSTIC FACTOR. PDSS2 IS A PUTATIVE TUMOR SUPPRESSOR, AND PROMOTER HYPERMETHYLATION IS A KEY REGULATORY MECHANISM IN HCC. DECREASED LEVELS OF PDSS2 MRNA EXPRESSION MAY REPRESENT A NOVEL BIOMARKER OF HCC. 2014 7 1843 31 EFFECTS OF TELOMERASE INHIBITOR ON EPIGENETIC CHROMATIN MODIFICATION ENZYMES IN MALIGNANCIES. TELOMERASE HAS A CRITICAL ROLE IN CELL PROLIFERATION, TUMOR MAINTAINING, AND THERAPY RESISTANCE, WHICH ACT BY MODIFYING MANY SIGNALING PATHWAYS. 2-[(E)-3-NAPHTALEN-2-YL-BUT-2-ENOYLAMINO]-BENZOIC ACID (BIBR1532) IS ONE OF THE MOST STUDIED TELOMERASE INHIBITORS, AND IT TARGETS TELOMERASE COMPONENTS TERC AND TERT. IN THIS NOVEL STUDY, WE AIMED TO INVESTIGATE THE EPIGENETIC EFFECTS OF BIBR1532 ON BOTH HEMATOLOGIC MALIGNANCIES AND SOLID TUMORS. K-562 HUMAN CHRONIC MYELOID LEUKEMIA CELL LINE AND U87MG GLIOBLASTOMA CELL LINE WERE COMPARED WITH CONTROL GROUPS WITHOUT BIBR1532 TREATMENT. CYTOTOXIC EFFECTS OF BIBR1532 WERE DETERMINED BY USING WST-1 ASSAY. APOPTOTIC EFFECTS OF BIBR1532 WERE DETECTED BY USING ANNEXIN V METHOD. TO ASSESS EXPRESSION CHANGES IN THE HUMAN EPIGENETIC CHROMATIN MODIFICATION ENZYME GENES, TOTAL RNA WAS ISOLATED FROM K-562 AND U87MG CELLS TREATED WITH BIBR1532 AND UNTREATED CONTROL CELLS. BIBR1532 INDUCED 2.41-FOLD APOPTOTIC CELL DEATH IN U87MG CELL LINES COMPARED WITH CONTROL GROUPS. APOPTOSIS WAS SLIGHTLY INDUCED IN K-562 CELLS WITH BIBR1532 TREATMENT COMPARED WITH CONTROL CELLS. WE OBSERVED THAT BIBR1532 ALSO REGULATES SIMILAR GENES IN BOTH CELL LINES, AND IT IS USEFUL ON EPIGENETIC MECHANISMS. AS A RESULT, TELOMERASE INHIBITOR BIBR1532 HAS A SIGNIFICANT EFFECT ON BOTH HEMATOLOGICAL MALIGNANCIES AND SOLID TUMORS. 2018 8 2453 27 EPIGENETIC SUPPRESSION OF THE IMMUNOREGULATOR MZB1 IS ASSOCIATED WITH THE MALIGNANT PHENOTYPE OF GASTRIC CANCER. PREDICTION OF TUMOR RECURRENCE AFTER CURATIVE RESECTION IS CRITICAL FOR DETERMINING THE PROGNOSIS OF PATIENTS WITH GASTRIC CANCER (GC). THE INITIATION AND PROGRESSION OF GC ARE ASSOCIATED WITH INAPPROPRIATE IMMUNE RESPONSES CAUSED BY CHRONIC INFLAMMATION OF THE GASTRIC MUCOSA. TO IDENTIFY IMMUNOREGULATORY MOLECULES INVOLVED IN GC PROGRESSION, GC CELL LINES AND 200 PAIRS OF TUMOR AND NORMAL TISSUES FROM PATIENTS WITH GC WERE ANALYZED FOR GENE EXPRESSION, AMPLIFICATION AND METHYLATION AS WELL AS FUNCTION OF A DIFFERENTIALLY EXPRESSED GENE. THE TRANSCRIPTOME ANALYSIS REVEALED THAT MARGINAL ZONE B AND B1 CELL SPECIFIC PROTEIN (MZB1) WAS EXPRESSED AT SIGNIFICANTLY DECREASED LEVELS IN PRIMARY GC TISSUES WHEN COMPARED WITH THE CORRESPONDING NORMAL GASTRIC MUCOSA. PCR ARRAY ANALYSIS EXPLORING GENES EXPRESSED COOPERATIVELY WITH MZB1 REVEALED THAT DIFFERENTIAL EXPRESSION OF MZB1 MRNA IN GC CELL LINES CORRELATED POSITIVELY WITH THE LEVELS OF THE MRNAS ENCODING ESTROGEN RECEPTOR 1 AND DESUMOYLATING ISOPEPTIDASE 1. HYPERMETHYLATION OF THE MZB1 PROMOTER WAS FREQUENT IN CELL LINES WITH DECREASED LEVELS OF MZB1 MRNA. SIRNA-MEDIATED KNOCKDOWN OF MZB1 SIGNIFICANTLY INCREASED PROLIFERATION, INVASION AND MIGRATION OF GC CELL LINES. LOW MZB1 EXPRESSION WAS AN INDEPENDENT PROGNOSTIC FACTOR FOR RECURRENCE AFTER CURATIVE GASTRECTOMY AND WAS ASSOCIATED SIGNIFICANTLY WITH INCREASED HEMATOGENOUS RECURRENCE. MZB1 ACTS AS A SUPPRESSOR OF GC. LOW MZB1 EXPRESSION IN THE PRIMARY GC TISSUE IS PREDICTIVE OF RECURRENCE AFTER CURATIVE RESECTION. 2016 9 1658 30 DOWN-REGULATION OF A PRO-APOPTOTIC PATHWAY REGULATED BY PCAF/ADA3 IN EARLY STAGE GASTRIC CANCER. THE LOSS OF P300/CBP-ASSOCIATED PROTEIN (PCAF) EXPRESSION IS ASSOCIATED WITH POOR CLINICAL OUTCOME IN GASTRIC CANCER, AND A POTENTIAL BIO-MARKER FOR INVASIVE AND AGGRESSIVE TUMORS. HOWEVER, THE MECHANISM LINKING LOSS OF PCAF TO THE ONSET OF GASTRIC CANCER HAS NOT BEEN IDENTIFIED. GIVEN THAT PCAF AND ITS BINDING PARTNER TRANSCRIPTIONAL ADAPTOR PROTEIN 3 (ADA3) WERE RECENTLY SHOWN TO REGULATE THE INTRINSIC (MITOCHONDRIAL) PATHWAY TO APOPTOSIS VIA EPIGENETIC REGULATION OF PHOSPHOFURIN ACIDIC CLUSTER SORTING PROTEINS 1 AND 2 (PACS1, PACS2), WE ANALYZED PCAF, ADA3, AND PACS1/2 EXPRESSION IN 99 PATIENT-MATCHED SURGICAL SAMPLES RANGING FROM NORMAL GASTRIC MUCOSA, THROUGH PRE-MALIGNANT CHRONIC GASTRITIS AND INTESTINAL METAPLASIA TO STAGE I-III INVASIVE CANCERS. PCAF MRNA LEVELS WERE NOT REDUCED IN EITHER PRE-MALIGNANT STATE BUT WERE SIGNIFICANTLY DOWN-REGULATED IN ALL STAGES OF GASTRIC CANCER, COMMENCING AT AJCC STAGE I (P < 0.05), THUS LINKING REDUCED PCAF EXPRESSION WITH EARLY MALIGNANT CHANGE. FURTHERMORE, PATIENTS WITH COMBINED REDUCTION OF PCAF AND PACS1 HAD SIGNIFICANTLY POORER OVERALL SURVIVAL (P = 0.0257), CONFIRMED IN AN INDEPENDENT DATASET OF 359 PATIENTS (P = 5.8 X 10E-6). AT THE PROTEIN LEVEL, PCAF, ADA3, AND PACS1 EXPRESSION WERE ALL SIGNIFICANTLY DOWN-REGULATED IN INTESTINAL-TYPE GASTRIC CANCER, AND CORRELATED WITH REDUCED PROGRESSION FREE SURVIVAL. WE CONCLUDE THAT A PRO-APOPTOTIC MECHANISM CENTERED ON THE INTRINSIC (MITOCHONDRIAL) PATHWAY AND REGULATED BY PCAF/ADA3 CAN INFLUENCE THE PROGRESSION FROM PREMALIGNANT TO MALIGNANT CHANGE, AND THUS ACT AS A TUMOR SUPPRESSION MECHANISM IN GASTRIC CANCER. 2018 10 4225 21 METHYLATION DEGREE OF METALLOPROTEINASE INHIBITOR RECK GENE: LINKS TO RECK PROTEIN LEVEL AND HEPATOCELLULAR CARCINOMA IN CHRONIC HCV INFECTION PATIENTS. THE RECK GENE, A TUMOR SUPPRESSOR GENE, INHIBITS ANGIOGENESIS, INVASION, AND TUMOR METASTASIS. EPIGENETIC REGULATION OF THE RECK GENE CONSTITUTES A POTENT APPROACH TO THE MOLECULAR BASIS OF LIVER MALIGNANCY. THIS STUDY AIMS TO EVALUATE THE PROMOTER METHYLATION STATUS OF THE RECK GENE AND ITS SERUM LEVEL IN PATIENTS WITH HEPATITIS C VIRUS (HCV)-RELATED HEPATOCELLULAR CARCINOMA (HCC) AND THE POTENTIAL ASSOCIATION OF RECK GENE METHYLATION WITH CLINICAL CRITERIA OF HCC. ONE HUNDRED AND FIFTY-FIVE SUBJECTS WERE INCLUDED (HEALTHY CONTROL [55], CHRONIC HCV PATIENTS [55], HCV-RELATED HCC PATIENTS [45]). THE METHYLATION STATUS OF THE RECK GENE PROMOTER AND SERUM RECK LEVEL WERE INVESTIGATED BY METHYLATION-SPECIFIC PCR AND ENZYME-LINKED IMMUNOSORBENT ASSAY TECHNIQUES, RESPECTIVELY. RECK GENE PROMOTER HYPERMETHYLATION WAS RECORDED IN 46.7% OF HCC PATIENTS, AND 10.9% OF HCV PATIENTS, BUT NOT IN CONTROL SUBJECTS (0%). IT WAS RELATED TO RECK PROTEIN LEVEL, VARICES, EDEMA, ASCITES, LYMPH NODE METASTASIS, VASCULAR INVASION, AND THE LARGEST DIAMETER OF FOCAL LESIONS. MEANWHILE, IT WAS NOT ASSOCIATED WITH FOCAL LESION NUMBER NOR DISTANT METASTASIS OF HCC. IN CONCLUSION, RECK GENE PROMOTER HYPERMETHYLATION IS LINKED TO HCV GENOTYPE-4-RELATED HCC. MOREOVER, DIFFERENT DEGREES OF RECK GENE PROMOTER METHYLATION ARE ASSOCIATED WITH SERUM RECK LEVEL, LYMPH NODE METASTASIS, AND VASCULAR INVASION, WHICH COULD PROVE ITS PATHOGENIC ROLE IN HEPATOCARCINOGENESIS IN CHRONIC HCV-INFECTED PATIENTS. 2021 11 1742 30 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 12 6243 40 THE MECHANISM OF APOLIPROTEIN A1 DOWN-REGULATED BY HEPATITIS B VIRUS. BACKGROUND: HEPATITIS B VIRUS (HBV) INFECTION CORRELATED WITH THE DEVELOPMENT OF CIRRHOSIS, LIVER FAILURE AND HEPATOCELLULAR CARCINOMA (HCC), POSES A HUGE HEALTH BURDEN ON THE GLOBAL COMMUNITY. HOWEVER, THE PATHOGENESIS OF CHRONIC HEPATITIS B (CHB) REMAINS UNCLEAR. APOLIPOPROTEIN A1 (APOA1) MAINLY SECRETED BY HEPATOCYTES, REPRESENTS THE MAJOR PROTEIN COMPONENT OF HIGH-DENSITY LIPOPROTEIN. APOA1 SECRETION MAY BE DISRUPTED BY HBV INFECTION. IN THIS STUDY, WE MAINLY INVESTIGATED THE MOLECULAR MECHANISM OF APOA1 DOWN REGULATED BY HBV FOR REVEALING THE PATHOGENESIS OF CHB. METHODS: APOA1 EXPRESSION IN LIVERS OF CHB PATIENTS AS WELL AS HEALTHY CONTROLS WERE PERFORMED BY REAL-TIME PCR (RT-PCR) AND WESTERN BLOT. THE SERUM APOA1 LEVELS WERE MEASURED BY ENZYMED-LINKED IMMUNOSORBENT ASSAY (ELISA). EXPRESSION OF APOA1 MRNA AND PROTEIN LEVELS WERE PERFORMED BY RT-PCR AND WESTERN BLOT IN HUMAN HEPATOMA HEPG2 CELLS AND SUBLINE HEPG2.2.15 CELLS. HBV EXPRESSION CONSTRUCT, PHBV1.3 WERE TRANSFECTED INTO HEPG2, THE CHANGES OF APOA1 MRNA AND PROTEIN EXPRESSION WERE DETECTED BY RT-PCR AND WESTERN BLOT. TO FURTHER STUDY THE MECHANISM OF APOA1 DOWN REGULATION BY HBV, 11 CPG ISLANDS IN APOA1 PROMOTOR WERE TESTED FOR DNA METHYLATION STATUS BY MSP. HEPG2.2.15 CELL LINES WERE TREATED WITH DNA METHYLTRANSFERASE INHIBITOR 5-AZA-DEOXYCYTIDINE (5-AZA-DC), THEN, EXPRESSION OF APOA1 MRNA AND HBV PARTICLES IN THE SUPERNATANT, AS WELL AS APOA1 PROTEIN LEVELS WERE DETECTED BY RT-PCR AND WESTERN BLOT. SECRETION OF HBSAG AND HBEAG IN HEPG2 CELLS COTRANSFECTED WITH PAPOA1 AND PHBV1.3 CONSTRUCTS WAS TESTED BY ELISA. MEANWHILE, SECRETION OF HBSAG AND HBEAG IN THE SUPERNATANT WERE QUANTIFIED BY ELISA IN THE HEPG2.2.15 CELLS TREATED WITH 5-AZA-DC PLUS APOA1 SIRNA. RESULTS: EXPRESSION OF APOA1 MRNA AND PROTEIN LEVELS, AS WELL AS SERUM APOA1 LEVELS IN CHB PATIENTS WERE DECREASED CORRESPONDING HEALTHY CONTROLS IN VIVO. IN ADDITION, THE EXPRESSION OF APOA1 MRNA AND PROTEIN LEVELS WERE DOWN REGULATED IN HEPG2.2.15 CELLS CORREPONDING HEPG2 CELLS, 11 CPG ISLANDS IN APOA1 PROMOTER WERE TESTED FOR METHYLATION STATUS BY MSP IN HEPG2.2.15 CELLS COMPARED TO HEPG2 CELLS, WHILE TWO CPG ISLANDS WERE FOUND HYPERMETHYLATED. EXPRESSION OF APOA1 MRNA AND PROTEIN LEVELS WERE INCREASED IN HEPG2.2.15 CELLS TREATED WITH DNA METHYLTRANSFERASE INHIBITOR 5-AZA-DC. FURTHERMORE, OVEREXPRESSION OF APOA1 CAN ENHANCE HBV EXPRESSION IN HEPG2 CELLS WHILE THE INHIBITORY EFFECT OF 5-AZA-DC ON HBV EXPRESSION WAS COMPLETELY ABOLISHED BY BLOCKING 5-AZA-DC-INDUCED UP-REGULATION OF APOA1 USING RNAI. CONCLUSIONS: EPIGENETIC SILENCING OF APOA1 GENE EXPRESSION BY CPG ISLAND DNA HYPERMETHYLATION INDUCED BY HBV MAY CONTRIBUTE TO THE PATHOGENESIS OF CHB. 2016 13 145 29 ABERRANT DNA METHYLATION STATUS AND MRNA EXPRESSION LEVEL OF SMG1 GENE IN CHRONIC MYELOID LEUKEMIA: A CASE-CONTROL STUDY. OOBJECTIVE: CHRONIC MYELOID LEUKEMIA (CML) IS A MYELOPROLIFERATIVE MALIGNANCY WITH DIFFERENT STAGES. ABERRANT EPIGENETIC MODIFICATIONS, SUCH AS DNA METHYLATION, HAVE BEEN INTRODUCED AS A SIGNATURE FOR DIVERSE CANCERS WHICH ALSO PLAYS A CRUCIAL ROLE IN CML PATHOGENESIS AND DEVELOPMENT. SUPPRESSOR WITH MORPHOGENETIC EFFECT ON GENITALIA (SMG1) GENE RECENTLY HAS BEEN BROUGHT TO THE SPOTLIGHT AS A POTENT TUMOR SUPPRESSOR GENE THAT CAN BE SUPPRESSED BY TUMORS FOR FURTHER PROGRESS. THE PRESENT STUDY AIMS TO INVESTIGATE SMG1 STATUS IN CML PATIENTS. MATERIALS AND METHODS: IN THIS CASE-CONTROL STUDY, PERIPHERAL BLOOD FROM 30 PATIENTS WITH DIFFERENT PHASES OF CML [NEW CASE (N)=10, COMPLETE MOLECULAR REMISSION (CMR)=10, BLASTIC PHASE (BP)=10] AND 10 HEALTHY SUBJECTS WERE COLLECTED. METHYLATION STATUS AND EXPRESSION LEVEL OF SMG1 GENE PROMOTER WAS ASSESSED BY METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION (MSP) AND QUANTITATIVE REVERSE-TRANSCRIPTION PCR, RESPECTIVELY. RESULTS: MSP RESULTS OF SMG1 GENE PROMOTOR IN THE NEW CASE GROUP WERE METHYLATED (60% METHYLATED, 30% HEMIMETHYLATED AND 10% UNMETHYLATED). ALL CMR AND CONTROL GROUP PATIENTS WERE UNMETHYLATED IN THE SMG1 GENE PROMOTER. IN THE BP GROUP, METHYLATED SMG1 PROMOTER WAS SEEN (50% OF PATIENTS HAD A METHYLATED STATUS AND 50% HAD HEMIMETHYLATED STATUS). IN COMPARISON WITH THE HEALTHY SUBJECTS, EXPRESSION LEVEL OF SMG1 IN THE NEW CASE GROUP WAS DECREASED (P<0.01); IN THE CMR GROUP AND BP-CML GROUPS, IT WAS INCREASED (P<0.05). NO SIGNIFICANT CORRELATION BETWEEN PATIENTS' HEMATOLOGICAL FEATURES AND SMG1 METHYLATION WAS SEEN. CONCLUSION: OUR RESULTS DEMONSTRATED THAT ABERRANT METHYLATION OF SMG1 OCCURRED IN CML PATIENTS AND IT HAD A SIGNIFICANT ASSOCIATION WITH SMG1 EXPRESSION. SMG1 GENE PROMOTER SHOWED DIVERSE METHYLATED STATUS AND SUBSEQUENT EXPRESSION LEVELS IN DIFFERENT PHASES OF CML. THESE FINDINGS SUGGESTED POSSIBLE PARTICIPATION OF SMG1 SUPPRESSION IN THE CML PATHOGENESIS. 2022 14 1622 32 DNA METHYLTRANSFERASES IN MALAR MELASMA AND THEIR MODIFICATION BY SUNSCREEN IN COMBINATION WITH 4% NIACINAMIDE, 0.05% RETINOIC ACID, OR PLACEBO. BACKGROUND: MALAR MELASMA HAS A CHRONIC AND RECURRENT CHARACTER THAT MAY BE RELATED TO EPIGENETIC CHANGES. OBJECTIVE: TO RECOGNIZE THE EXPRESSION AND DNA METHYLATION OF DNA METHYLTRANSFERASES (DNMTS) IN MALAR MELASMA AND PERILESIONAL SKIN, AS WELL AS THE CHANGES IN DNMTS AFTER THEIR TREATMENT WITH SUNSCREEN IN COMBINATION WITH 4% NIACINAMIDE, 0.05% RETINOIC ACID, OR PLACEBO. METHODS: THIRTY FEMALE PATIENTS WERE CLINICALLY EVALUATED FOR THE EXPRESSION OF DNMT1 AND DNMT3B USING REAL-TIME PCR AND IMMUNOFLUORESCENCE. THESE INITIAL RESULTS WERE COMPARED TO RESULTS AFTER EIGHT WEEKS OF TREATMENT WITH SUNSCREEN IN COMBINATION WITH NIACINAMIDE, RETINOIC ACID, OR PLACEBO. RESULTS: THE RELATIVE EXPRESSION OF DNMT1 WAS SIGNIFICANTLY ELEVATED IN MELASMA COMPARED WITH UNAFFECTED SKIN IN ALL SUBJECTS, INDICATING DNA HYPERMETHYLATION. AFTER TREATMENT, IT WAS DECREASED IN ALL GROUPS: NIACINAMIDE (7 VERSUS 1; P<0.01), RETINOIC ACID (7 VERSUS 2; P<0.05), AND PLACEBO (7 VERSUS 3; P<0.05), WHICH CORRELATES WITH CLINICAL IMPROVEMENT. DNMT3B WAS NOT OVEREXPRESSED IN LESIONAL SKIN BUT REDUCED IN ALL GROUPS. CONCLUSIONS: WE FOUND DNA HYPERMETHYLATION IN MELASMA LESIONS. ENVIRONMENTAL FACTORS SUCH AS SOLAR RADIATION MAY INDUCE CELLULAR CHANGES THAT TRIGGER HYPERPIGMENTATION THROUGH THE ACTIVATION OF PATHWAYS REGULATED BY EPIGENETIC MODIFICATIONS. HOWEVER, LIMITING OR DECREASING DNA METHYLATION THROUGH SUNSCREEN, NIACINAMIDE, AND RETINOIC ACID TREATMENTS THAT PROVIDE PHOTOPROTECTION AND GENETIC TRANSCRIPTION CAN COUNTERACT THIS. 2019 15 1798 39 EFFECT OF HELICOBACTER PYLORI INFECTION ON GATA-5 AND TFF1 REGULATION, COMPARISON BETWEEN PEDIATRIC AND ADULT PATIENTS. BACKGROUND: GATA FACTORS, WHICH CONSTITUTE A FAMILY OF TRANSCRIPTION REGULATORY PROTEINS, PARTICIPATE IN GASTROINTESTINAL DEVELOPMENT. TREFOIL FACTOR 1 (TFF1) PLAYS A CRUCIAL ROLE IN MUCOSAL DEFENSE AND HEALING, AND EVIDENCE SUGGESTS THAT GATA-5 MEDIATED ITS REGULATION. GASTRIC CANCER IS A MULTIPLE-STEP PROCESS TRIGGERED BY HELICOBACTER PYLORI AND IS CHARACTERIZED BY ACCUMULATION OF MOLECULAR AND EPIGENETIC ALTERATION. THE AIM OF THIS STUDY WAS TO EVALUATE THE EFFECT OF H. PYLORI INFECTION ON THE REGULATION OF GATA-5 AND TFF1 IN VITRO AND IN VIVO. RESULTS: INFECTED CELLS EXHIBITED UPREGULATION OF GATA-5 AND TFF1 AFTER 48 H. AN INCREASE IN GATA-5 AND TFF1 MRNA LEVELS WAS ALSO FOUND IN MICE SAMPLES AFTER 6 AND 12 MONTHS OF INFECTION, RESPECTIVELY. IN HUMAN SAMPLES, WE FOUND AN ASSOCIATION BETWEEN H. PYLORI INFECTION AND GATA-5 UPREGULATION. IN FACT, AMONG H. PYLORI-INFECTED PATIENTS, HYPERMETHYLATION WAS OBSERVED IN 45.5% OF PEDIATRIC SAMPLES, IN 62.6% OF CHRONIC GASTRITIS SAMPLES, AND IN 63% OF GASTRIC CANCER SAMPLES. REGARDING TFF1, THE EXPRESSION LEVELS WERE SIMILAR IN PEDIATRICS AND ADULTS PATIENTS, AND WERE INDEPENDENT OF H. PYLORI INFECTION, AND THE EXPRESSION OF THESE FACTORS WAS DOWNREGULATED IN GASTRIC CANCER SAMPLES. GATA-5 PROMOTER METHYLATION WAS ASSOCIATED WITH A DECREASE IN TFF1 MRNA LEVELS. CONCLUSIONS: OUR RESULTS SUGGEST THAT THE UPREGULATION OF GATA-5 AND TFF1 OBSERVED IN VITRO AND IN VIVO MAY BE CORRELATED WITH A PROTECTIVE EFFECT OF THE MUCOSA IN RESPONSE TO INFECTION. THE EPIGENETIC INACTIVATION OF GATA-5 OBSERVED IN HUMAN BIOPSIES FROM INFECTED PATIENTS MAY SUGGEST THAT THIS ALTERATION IS AN EARLY EVENT OCCURRING IN ASSOCIATION WITH H. PYLORI INFECTION. 2018 16 1668 37 DOWNREGULATION OF SOCS1 INCREASES INTERFERON-INDUCED ISGYLATION DURING DIFFERENTIATION OF INDUCED-PLURIPOTENT STEM CELLS TO HEPATOCYTES. BACKGROUND & AIMS: INCREASED EXPRESSION OF IFN-STIMULATED GENE 15 (ISG15) AND SUBSEQUENTLY INCREASED ISGYLATION ARE KEY FACTORS IN THE HOST RESPONSE TO VIRAL INFECTION. IN THIS STUDY, WE SOUGHT TO CHARACTERIZE THE EXPRESSION OF ISG15, ISGYLATION, AND ASSOCIATED ENZYMES AT EACH STAGE OF DIFFERENTIATION FROM INDUCED PLURIPOTENT STEM CELLS (IPSCS) TO HEPATOCYTES. METHODS: TO STUDY THE REGULATION OF ISGYLATION, WE UTILIZED PATIENT SAMPLES AND IN VITRO CELL CULTURE MODELS INCLUDING IPSCS, HEPATOCYTES-LIKE CELLS, IMMORTALIZED CELL LINES, AND PRIMARY HUMAN HEPATOCYTES. PROTEIN/MRNA EXPRESSION WERE MEASURED FOLLOWING TREATMENT WITH POLY(I:C), IFNALPHA AND HCV INFECTION. RESULTS: WHEN COMPARED TO HLCS, WE OBSERVED SEVERAL NOVEL ASPECTS OF THE ISGYLATION PATHWAY IN IPSCS. THESE INCLUDE A LOWER BASELINE EXPRESSION OF THE ISGYLATION-ACTIVATING ENZYME, UBE1L, A LACK OF IFN-INDUCED EXPRESSION OF THE ISGYLATION-CONJUGATION ENZYME UBE2L6, AN ATTENUATED ACTIVATION OF THE TRANSCRIPTION FACTOR STAT1 AND CONSTITUTIVE EXPRESSION OF SOCS1. ISGYLATION WAS OBSERVED IN IPSCS FOLLOWING DOWNREGULATION OF SOCS1, WHICH FACILITATED STAT1 ACTIVATION AND SUBSEQUENTLY INCREASED EXPRESSION OF UBE2L6. INTRIGUINGLY, HCV PERMISSIVE TRANSFORMED HEPATOMA CELL LINES DEMONSTRATED HIGHER INTRINSIC EXPRESSION OF SOCS1 AND WEAKER ISGYLATION FOLLOWING IFN TREATMENT. SOCS1 DOWNREGULATION IN HCV-INFECTED HUH 7.5.1 CELLS LED TO INCREASED ISGYLATION. CONCLUSIONS: HEREIN, WE SHOW THAT HIGH BASAL LEVELS OF SOCS1 INHIBIT STAT1 ACTIVATION AND SUBSEQUENTLY IFN-INDUCED UBE2L6 AND ISGYLATION IN IPSCS. FURTHERMORE, AS IPSCS DIFFERENTIATE INTO HEPATOCYTES, EPIGENETIC MECHANISMS REGULATE ISGYLATION BY MODIFYING UBE1L AND SOCS1 EXPRESSION LEVELS. OVERALL, THIS STUDY DEMONSTRATES THAT THE DEVELOPMENT OF CELL-INTRINSIC INNATE IMMUNITY DURING THE DIFFERENTIATION OF IPSCS TO HEPATOCYTES PROVIDES INSIGHT INTO CELL TYPE-SPECIFIC REGULATION OF HOST DEFENSE RESPONSES AND RELATED ONCOGENIC PROCESSES. IMPACT AND IMPLICATIONS: TO ELUCIDATE THE MECHANISM UNDERLYING REGULATION OF ISGYLATION, A KEY PROCESS IN THE INNATE IMMUNE RESPONSE, WE STUDIED CHANGES IN ISGYLATION-ASSOCIATED GENES AT THE DIFFERENT STAGES OF DIFFERENTIATION FROM IPSCS TO HEPATOCYTES. WE FOUND THAT HIGH BASAL LEVELS OF SOCS1 INHIBIT STAT1 ACTIVATION AND SUBSEQUENTLY IFN-INDUCED UBE2L6 AND ISGYLATION IN IPSCS. IMPORTANTLY, EPIGENETIC REGULATION OF SOCS1 AND SUBSEQUENTLY ISGYLATION MAY BE IMPORTANT FACTORS IN THE DEVELOPMENT OF CELL TYPE-SPECIFIC HOST DEFENSE RESPONSES IN HEPATOCYTES THAT SHOULD BE CONSIDERED WHEN STUDYING CHRONIC INFECTIONS AND ONCOGENIC PROCESSES IN THE LIVER. 2022 17 2974 27 GENETIC AND METHYLATION STATUS OF CDKN2A (P14(ARF)/P16(INK4A)) AND TP53 GENES IN RECURRENT RESPIRATORY PAPILLOMATOSIS. RECURRENT RESPIRATORY PAPILLOMATOSIS (RRP) IS A RARE AND CHRONIC DISEASE AFFECTING THE UPPER AIRWAY WITH PAPILLOMATOUS LESIONS CAUSED BY THE HUMAN PAPILLOMAVIRUS (HPV) INFECTION, ESPECIALLY HPV-6 AND/OR HPV-11 TYPES. LITTLE IS KNOWN ABOUT THE GENETIC AND EPIGENETIC DRIVERS IN RRP PATHOPHYSIOLOGY. FOR THIS PURPOSE, WE ANALYZED 27 PAPILLOMATOUS LESIONS FROM PATIENTS WITH RRP TO EVALUATE SOMATIC MUTATIONS AND METHYLATION STATUS IN CDKN2A (P14(ARF)/P16(INK4A)) AND TP53, WHICH ARE KEY TUMOR SUPPRESSOR GENES FOR THE CELL CYCLE CONTROL. SANGER SEQUENCING ANALYSIS REVEALED ONE SOMATIC MUTATION IN TP53 (C.733_734INSA) AND FOUR MUTATIONS IN CDKN2A (C.-30G > T, C.29_30INSA, C.69DELT, AND C.300C > A). THESE MUTATIONS WERE OBSERVED IN 10 PATIENTS, 6 OF WHICH CARRIED DOUBLE MUTATION. FURTHERMORE, 50% (5/10) OF THESE PATIENTS CARRYING SOMATIC MUTATIONS HAD RRP SEVERITY, REPRESENTING 62.5% (5/8) OF THE SEVERITY CASES IN THIS STUDY, ALBEIT NO SIGNIFICANT ASSOCIATION WAS FOUND BETWEEN SOMATIC MUTATIONS AND DISEASE SEVERITY. METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION ASSAYS REVEALED P14(ARF) PROMOTER HYPERMETHYLATION IN 100% OF CASES, FOLLOWED BY TP53 (96.3%) AND P16(INK4A) (55.6%), SUGGESTING THE INFLUENCE OF HPV IN THE DNA METHYLATION MACHINERY. IN CONCLUSION, SOMATIC MUTATIONS WERE NOT COMMON EVENTS IDENTIFIED IN PATIENTS WITH RRP. HOWEVER, EPIGENETIC MODULATION BY HIGH METHYLATION RATES, PARTICULARLY FOR THE P14(ARF)/TP53 PATHWAY, SEEMS TO BE IN THE COURSE OF RRP DEVELOPMENT. 2022 18 3439 30 HYPERMETHYLATION AND LOSS OF EXPRESSION OF GLUTATHIONE PEROXIDASE-3 IN BARRETT'S TUMORIGENESIS. CHRONIC GASTROESOPHAGEAL REFLUX DISEASE IS A KNOWN RISK FACTOR FOR BARRETT'S ESOPHAGUS (BE), WHICH INDUCES OXIDATIVE MUCOSAL DAMAGE. GLUTATHIONE PEROXIDASE-3 (GPX3) IS A SECRETORY PROTEIN WITH POTENT EXTRACELLULAR ANTIOXIDANT ACTIVITY. IN THIS STUDY, WE HAVE INVESTIGATED THE MRNA AND PROTEIN EXPRESSION OF GPX3, AND EXPLORED PROMOTER HYPERMETHYLATION AS AN EPIGENETIC MECHANISM FOR GPX3 GENE INACTIVATION DURING BARRETT'S CARCINOGENESIS. QUANTITATIVE REAL-TIME REVERSE TRANSCRIPTION POLYMERASE CHAIN REACTION ON 42 BARRETT'S ADENOCARCINOMAS (BAS) REVEALED CONSISTENTLY REDUCED LEVELS OF GPX3 MRNA IN 91% OF TUMOR SAMPLES. GPX3 PROMOTER HYPERMETHYLATION WAS DETECTED IN 62% OF BARRETT'S METAPLASIA, 82% OF DYSPLASIA, AND 88% OF BA SAMPLES. HYPERMETHYLATION OF BOTH ALLELES OF GPX3 WAS MOST FREQUENTLY SEEN IN BAS (P = .001). IMMUNOHISTOCHEMICAL STAINING OF GPX3 IN MATCHING TISSUE SECTIONS (NORMAL, BE, BARRETT'S DYSPLASIA, AND BA) REVEALED STRONG IMMUNOSTAINING FOR GPX3 IN NORMAL ESOPHAGEAL AND GASTRIC TISSUES. HOWEVER, WEAK TO ABSENT GPX3 STAINING WAS OBSERVED IN BARRETT'S DYSPLASIA AND ADENOCARCINOMA SAMPLES WHERE THE PROMOTER WAS HYPERMETHYLATED. THE DEGREE OF LOSS OF IMMUNOHISTOCHEMISTRY CORRELATED WITH THE HYPERMETHYLATION PATTERN (MONOALLELIC VERSUS BIALLELIC). THE OBSERVED HIGH FREQUENCY OF PROMOTER HYPERMETHYLATION AND PROGRESSIVE LOSS OF GPX3 EXPRESSION IN BA AND ITS ASSOCIATED LESIONS, TOGETHER WITH ITS KNOWN FUNCTION AS A POTENT ANTIOXIDANT, SUGGEST THAT EPIGENETIC INACTIVATION AND REGULATION OF GLUTATHIONE PATHWAY MAY BE CRITICAL IN THE DEVELOPMENT AND PROGRESSION OF BE. 2005 19 154 19 ABERRANT METHYLATION OF NUCLEOTIDE EXCISION REPAIR GENES IS ASSOCIATED WITH CHRONIC ARSENIC POISONING. OBJECTIVE: TO DEFINE WHETHER ABERRANT METHYLATION OF DNA REPAIR GENES IS ASSOCIATED WITH CHRONIC ARSENIC POISONING. METHODS: HUNDRED AND TWO ENDEMIC ARSENICOSIS PATIENTS AND 36 HEALTHY SUBJECTS WERE RECRUITED. METHYLIGHT AND BISULFITE SEQUENCING (BSP) ASSAYS WERE USED TO EXAMINE THE METHYLATION STATUS OF ERCC1, ERCC2 AND XPC GENES IN PERIPHERAL BLOOD LYMPHOCYTES (PBLS) AND SKIN LESIONS OF ARSENICOSIS PATIENTS AND NAASO(2)-TREATED HACAT CELLS. RESULTS: HYPERMETHYLATION OF ERCC1 AND ERCC2 AND SUPPRESSED GENE EXPRESSION WERE FOUND IN PBLS AND SKIN LESIONS OF ARSENICOSIS PATIENTS AND WAS CORRELATED WITH THE LEVEL OF ARSENIC EXPOSURE. PARTICULARLY, THE EXPRESSION OF ERCC1 AND ERCC2 WAS ASSOCIATED WITH THE SEVERITY OF SKIN LESIONS. IN VITRO STUDIES REVEALED AN INDUCTION OF ERCC2 HYPERMETHYLATION AND DECREASED MRNA EXPRESSION IN RESPONSE TO NAASO(2) TREATMENT. CONCLUSION: HYPERMETHYLATION OF ERCC1 AND ERCC2 AND CONCOMITANT SUPPRESSION OF GENE EXPRESSION MIGHT BE SERVED AS THE EPIGENETIC MARKS ASSOCIATED WITH ARSENIC EXPOSURE AND ADVERSE HEALTH EFFECTS. 2017 20 5775 30 SPERMIDINE/SPERMINE N(1)-ACETYLTRANSFERASE ACTIVITY ASSOCIATES WITH WHITE BLOOD CELL COUNT IN MYELOID LEUKEMIAS. THE METABOLISM OF POLYAMINES, THE CATIONIC SMALL MOLECULES ESSENTIAL FOR CELL PROLIFERATION AND DIFFERENTIATION, IS ALTERED IN CANCER CELLS AND CAN BE EXPLOITED IN CANCER DIAGNOSIS AND THERAPY. SPERMIDINE/SPERMINE N(1)-ACETYLTRANSFERASE (SSAT), WHICH REGULATES INTRACELLULAR LEVELS OF POLYAMINES BY CATABOLIZING SPERMIDINE AND SPERMINE, HAS A CONTROVERSIAL ROLE IN THE DEVELOPMENT OF CANCERS. IN THIS STUDY, THE POLYAMINE METABOLISM AND FUNCTION OF SSAT WERE CHARACTERIZED IN ACUTE MYELOID LEUKEMIA (AML), CHRONIC MYELOID LEUKEMIA (CML), AND ACUTE LYMPHOID LEUKEMIA PATIENT SAMPLES. ALSO, MICE OVEREXPRESSING SSAT AND HAVING A MYELOPROLIFERATIVE PHENOTYPE WERE ANALYZED FOR THEIR RESPONSE TO DECITABINE AND HISTONE DEACETYLASE INHIBITOR TRICHOSTATIN A. THE PRESENCE OF EPIGENETIC FACTORS IN THE BONE MARROW CELLS OF SSAT MICE WAS ANALYZED. ELEVATED LEVELS OF SPERMIDINE AND SPERMINE, AS WELL AS INCREASED ACTIVITY OF SSAT, WERE DETECTED IN AML, CML, AND ACUTE LYMPHOID LEUKEMIA PATIENTS COMPARED WITH THE CONTROLS. HOWEVER, WE FOUND SSAT ACTIVITY TO BE ASSOCIATED WITH WHITE BLOOD CELL COUNT ONLY IN AML AND CML PATIENTS. DECITABINE TREATMENT BROUGHT THE PERIPHERAL BLOOD AND BONE MARROW CELL COUNTS OF SSAT MICE TO THE LEVEL OF WILD-TYPE MICE. SPERMIDINE/SPERMINE N(1)-ACETYLTRANSFERASE MICE HAD INCREASED HISTONE METHYLATION AND AN INCREASED LEVEL OF HISTONE DEACETYLASE 1 IN THEIR BONE MARROW CELLS. THE STUDY SUGGESTS THAT SSAT INFLUENCES THE DEVELOPMENT OF MYELOID MALIGNANCIES, AND EPIGENETIC FACTORS PARTLY CONTRIBUTE TO THE SSAT OVEREXPRESSION-INDUCED MYELOPROLIFERATIVE DISEASE IN MICE. 2014