1 6593 113 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 2 1950 39 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 4696 35 NF-KAPPAB REPRESSES RETINOIC ACID RECEPTOR-MEDIATED GPRC5A TRANSACTIVATION IN LUNG EPITHELIAL CELLS TO PROMOTE NEOPLASIA. CHRONIC INFLAMMATION IS ASSOCIATED WITH LUNG TUMORIGENESIS, IN WHICH NF-KAPPAB-MEDIATED EPIGENETIC REGULATION PLAYS A CRITICAL ROLE. LUNG TUMOR SUPPRESSOR G PROTEIN-COUPLED RECEPTOR, FAMILY C, MEMBER 5A (GPRC5A), IS REPRESSED IN MOST NON-SMALL CELL LUNG CANCER (NSCLC); HOWEVER, THE MECHANISMS REMAIN UNCLEAR. HERE, WE SHOW THAT NF-KAPPAB ACTS AS A TRANSCRIPTIONAL REPRESSOR IN SUPPRESSION OF GPRC5A. NF-KAPPAB INDUCED GPRC5A REPRESSION BOTH IN VITRO AND IN VIVO. INTRIGUINGLY, TRANSACTIVATION OF NF-KAPPAB DOWNSTREAM TARGETS WAS NOT REQUIRED, BUT THE TRANSACTIVATION DOMAIN OF RELA/P65 WAS REQUIRED FOR GPRC5A REPRESSION. NF-KAPPAB DID NOT BIND TO ANY POTENTIAL CIS-ELEMENT IN THE GPRC5A PROMOTER. INSTEAD, P65 WAS COMPLEXED WITH RETINOIC ACID RECEPTOR ALPHA/BETA (RARALPHA/BETA) AND RECRUITED TO THE RA RESPONSE ELEMENT SITE AT THE GPRC5A PROMOTER, RESULTING IN DISRUPTED RNA POLYMERASE II COMPLEXING AND SUPPRESSED TRANSCRIPTION. NOTABLY, PHOSPHORYLATION ON SERINE 276 OF P65 WAS REQUIRED FOR INTERACTION WITH RARALPHA/BETA AND REPRESSION OF GPRC5A. MOREOVER, NF-KAPPAB-MEDIATED EPIGENETIC REPRESSION WAS THROUGH SUPPRESSION OF ACETYLATED HISTONE H3K9 (H3K9AC), BUT NOT DNA METHYLATION OF THE CPG ISLANDS, AT THE GPRC5A PROMOTER. CONSISTENTLY, A HISTONE DEACETYLASE INHIBITOR, BUT NOT DNA METHYLATION INHIBITOR, RESTORED GPRC5A EXPRESSION IN NSCLC CELLS. THUS, NF-KAPPAB INDUCES TRANSCRIPTIONAL REPRESSION OF GPRC5A VIA A COMPLEX WITH RARALPHA/BETA AND MEDIATES EPIGENETIC REPRESSION VIA SUPPRESSION OF H3K9AC. 2023 4 136 32 ABERRANT DNA HYPERMETHYLATION PATTERNS LEAD TO TRANSCRIPTIONAL SILENCING OF TUMOR SUPPRESSOR GENES IN UVB-EXPOSED SKIN AND UVB-INDUCED SKIN TUMORS OF MICE. OVEREXPOSURE OF THE HUMAN SKIN TO SOLAR ULTRAVIOLET (UV) RADIATION IS THE MAJOR ETIOLOGIC FACTOR FOR DEVELOPMENT OF SKIN CANCERS. HERE, WE REPORT THE RESULTS OF EPIGENETIC MODIFICATIONS IN UV-EXPOSED SKIN AND SKIN TUMORS IN A SYSTEMATIC MANNER. THE SKIN AND TUMOR SAMPLES WERE COLLECTED AFTER CHRONIC EXPOSURE OF THE SKIN OF SKH-1 HAIRLESS MICE TO UVB RADIATION USING A WELL-ESTABLISHED PHOTOCARCINOGENESIS PROTOCOL. WE FOUND A DISTINCT DNA HYPERMETHYLATION PATTERN IN THE UVB-EXPOSED EPIDERMAL SKIN AND UVB-INDUCED SKIN TUMORS THAT WAS ASSOCIATED WITH THE ELEVATED EXPRESSION AND ACTIVITY OF THE DNA METHYLTRANSFERASES (DNMT) 1, DNMT3A AND DNMT3B. TO EXPLORE THE ROLE OF HYPERMETHYLATION IN SKIN PHOTOCARCINOGENESIS, WE FOCUSED ON THE P16(INK4A) AND RASSF1A TUMOR SUPPRESSOR GENES, WHICH ARE TRANSCRIPTIONALLY SILENCED ON METHYLATION. WE ESTABLISHED THAT THE SILENCING OF THESE GENES IN UVB-EXPOSED EPIDERMIS AND UVB-INDUCED SKIN TUMORS IS ASSOCIATED WITH A NETWORK OF EPIGENETIC MODIFICATIONS, INCLUDING HYPOACETYLATION OF HISTONE H3 AND H4 AND INCREASED HISTONE DEACETYLATION, AS WELL AS RECRUITMENT OF METHYL-BINDING PROTEINS, INCLUDING MECP2 AND MBD1, TO THE METHYLATED CPGS. HIGHER LEVELS OF DNA METHYLATION AND DNMT ACTIVITY IN HUMAN SQUAMOUS CELL CARCINOMA SPECIMENS THAN IN NORMAL HUMAN SKIN SUGGEST THAT THE DATA ARE RELEVANT CLINICALLY. OUR DATA INDICATE FOR THE FIRST TIME THAT UVB-INDUCED DNA HYPERMETHYLATION, ENHANCED DNMT ACTIVITY AND HISTONE MODIFICATIONS OCCUR IN UVB-EXPOSED SKIN AND UVB-INDUCED SKIN TUMORS AND SUGGEST THAT THESE EVENTS ARE INVOLVED IN THE SILENCING OF TUMOR SUPPRESSOR GENES AND IN SKIN TUMOR DEVELOPMENT. 2011 5 3718 37 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 3128 36 GIPC-REGULATED IGFBP-3 PROMOTES HSC MIGRATION IN VITRO AND PORTAL HYPERTENSION IN VIVO THROUGH A BETA1-INTEGRIN PATHWAY. BACKGROUND & AIMS: TRANSFORMING GROWTH FACTOR (TGF-BETA)-INDUCED ACTIVATION OF QUIESCENT HEPATIC STELLATE CELLS (HSCS) AND THEIR TRANSFORMATION TO MYOFIBROBLASTS IS A KEY EVENT IN LIVER FIBROSIS AND PORTAL HYPERTENSION. GIPC (ALSO REFERRED TO AS SYNECTIN) IS A DOWNSTREAM SIGNAL ACTIVATION MOLECULE OF TGF-BETA AND OTHER RECEPTORS. IN THIS STUDY, WE SOUGHT TO IDENTIFY NOVEL GENES TARGETED BY TGF-BETA AND GIPC AND ELUCIDATE IF AND HOW THEY MAY CONTRIBUTE TO LIVER FIBROSIS. METHODS: WE PERFORMED SEQUENTIAL MESSENGER RNA SEQUENCING ANALYSIS ON TGF-BETA-STIMULATED HSCS AND THEN ON TGF-BETA-STIMULATED HSCS IN THE PRESENCE AND ABSENCE OF GIPC ALSO REFERRED TO AS SYNECTIN (GIPC) KNOCKDOWN. INSULIN-LIKE GROWTH FACTOR BINDING PROTEIN-3 (IGFBP-3) TRANSPORT PROTEIN EMERGED AS A TOP ACTIVATION TARGET OF BOTH TGF-BETA AND GIPC. QUANTITATIVE POLYMERASE CHAIN REACTION, ENZYME-LINKED IMMUNOSORBENT ASSAY, TARGETED CHROMATIN IMMUNOPRECIPITATION, AND WESTERN BLOT ANALYSIS WERE DONE FOR FURTHER CONFIRMATION. RESULTS: IGFBP-3, AN INSULIN GROWTH FACTOR TRANSPORT PROTEIN, EMERGED AS A TOP ACTIVATION TARGET OF BOTH TGF-BETA AND GIPC, WHICH WAS CONFIRMED BY QUANTITATIVE POLYMERASE CHAIN REACTION, ENZYME-LINKED IMMUNOSORBENT ASSAY, AND WESTERN BLOT ANALYSIS. TARGETED CHROMATIN IMMUNOPRECIPITATION SHOWED THAT GIPC INCREASES THE HISTONE 3 LYSINE 27 (H3K27) ACETYLATION ACTIVATING MARK AND CONCURRENTLY DECREASES THE H3K27 INHIBITORY TRIMETHYLATION (H3K27M3) MARK, PROVIDING AN EPIGENETIC CORRELATE TO THE GENE REGULATION CHANGES. IN VIVO, GLOBAL KNOCKOUT OF IGFBP-3 MICE RESULTED IN ATTENUATION OF HSC ACTIVATION MARKERS AND ATTENUATION OF PORTAL PRESSURE IN RESPONSE TO CHRONIC LIVER INJURY MODELS. ANALYSIS OF SERUM LEVELS FROM CIRRHOTIC PATIENTS ALSO SHOWED AN IGFBP-3 INCREASE OF MORE THAN 2-FOLD COMPARED WITH HEALTHY CONTROLS. FINALLY, IN VITRO MECHANISM STUDIES SHOWED THAT IGFBP-3 PROMOTES HSC MIGRATION THROUGH INTEGRIN-DEPENDENT PHOSPHORYLATION OF PROTEIN KINASE B. CONCLUSIONS: TGF-BETA UP-REGULATES IGFBP-3 THROUGH GIPC, LEADING TO INCREASED HSC MIGRATION IN VITRO AND PROMOTES PORTAL HYPERTENSION IN VIVO. THESE STUDIES SUPPORT THE ROLE OF IGFBP-3 AS A POTENTIAL PATHOPHYSIOLOGIC TARGET OR BIOMARKER IN CHRONIC LIVER DISEASE. 2020 7 1067 32 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 8 2863 33 FUNCTION OF DNA METHYLTRANSFERASE 3A IN LEAD (PB(2+) )-INDUCED CYCLOOXYGENASE-2 GENE. LEAD IONS (PB(2+) ) ARE TOXIC INDUSTRIAL POLLUTANTS ASSOCIATED WITH CHRONIC INFLAMMATORY DISEASES IN HUMANS AND ANIMALS. PREVIOUSLY, WE FOUND THAT PB(2+) IONS INDUCE COX-2 GENE EXPRESSION VIA THE EGF RECEPTOR/NUCLEAR FACTOR-KAPPAB SIGNAL TRANSDUCTION PATHWAY IN EPIDERMOID CARCINOMA CELL LINE A431. IN THIS STUDY, TO SEE WHETHER PB(2+) IONS AFFECT COX-2 EXPRESSION BY EPIGENETIC MECHANISMS, WE LOOKED AT THE MRNAS OF DNA METHYLTRANSFERASES (DNMTS) USING REAL-TIME PCR OF TOTAL RNA FROM THESE CELLS. CELLS EXPOSED TO PB(2+) HAD LOW LEVELS OF DNMT3A MRNA, WHEREAS THE LEVELS OF DNMT1 AND DNMT3B MRNAS REMAINED UNCHANGED. PRETREATMENT OF CELLS WITH DNMT INHIBITOR 5-AZA-2'-DEOXYCYTIDINE (5 MUM) FOLLOWED BY PB(2+) (1 MUM) SIGNIFICANTLY INCREASED LEVELS OF COX-2 MRNA COMPARED WITH CELLS TREATED WITH PB(2+) ALONE. OVEREXPRESSION OF TUMOR SUPPRESSOR GENE RB CORRELATED WITH AN INCREASE IN COX-2 MRNA AND A DECREASE IN DNMT3A MRNA. CONVERSELY, OVEREXPRESSION OF TRANSCRIPTION FACTOR E2F1 CORRELATED WITH A DECREASE IN COX-2 MRNA AND AN INCREASE IN DMNT3A MRNA. PRETREATMENT WITH EGFR INHIBITORS AG1478 AND PD153035 SIGNIFICANTLY LIMITED PB(2+) -INDUCED REDUCTION IN DNMT3A MRNA. IN ADDITION, GENE KNOCKDOWN OF DNMT3A WITH SHORT HAIRPIN RNA CORRELATED WITH INCREASED COX-2 MRNA INDUCED BY PB(2+) . OUR FINDINGS SUGGEST PB(2+) IONS INDUCE COX-2 EXPRESSION INDIRECTLY BY REDUCING DNMT3A METHYLATION OF THE COX-2 PROMOTER VIA TRANSCRIPTION FACTORS RB AND E2F1. 2015 9 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 10 3049 30 GENOME-WIDE ANALYSIS REVEALS ZINC TRANSPORTER ZIP9 REGULATED BY DNA METHYLATION PROMOTES RADIATION-INDUCED SKIN FIBROSIS VIA THE TGF-BETA SIGNALING PATHWAY. RADIATION-INDUCED SKIN FIBROSIS IS A DETRIMENTAL AND CHRONIC DISORDER THAT OCCURS AFTER RADIATION EXPOSURE. DNA METHYLATION HAS BEEN CHARACTERIZED AS AN IMPORTANT REGULATORY MECHANISM OF MULTIPLE PATHOLOGICAL PROCESSES. IN THIS STUDY, WE COMPARED THE GENOME-WIDE DNA METHYLATION STATUS IN RADIATION-INDUCED FIBROTIC SKIN AND ADJACENT NORMAL TISSUES OF RATS BY METHYLATED DNA IMMUNOPRECIPITATION SEQUENCING. RADIATION-INDUCED FIBROTIC SKIN SHOWED DIFFERENTIALLY METHYLATED REGIONS ASSOCIATED WITH 3,650 PROTEIN-CODING GENES, 72 MICRORNAS, 5,836 LONG NONCODING RNAS AND 3 PIWI-INTERACTING RNAS. BY INTEGRATING THE MRNA AND METHYLATION PROFILES, THE ZINC TRANSPORTER SLC39A9/ZIP9 WAS INVESTIGATED IN GREATER DETAIL. THE PROTEIN LEVEL OF ZIP9 WAS INCREASED IN IRRADIATED SKIN TISSUES OF HUMANS, MONKEYS, AND RATS, ESPECIALLY IN RADIOGENIC FIBROTIC SKIN TISSUES. RADIATION INDUCED THE DEMETHYLATION OF A CPG DINUCLEOTIDE IN EXON 1 OF ZIP9 THAT RESULTED IN RECRUITMENT OF THE TRANSCRIPTIONAL FACTOR SP1 AND INCREASED ZIP9 EXPRESSION. OVEREXPRESSION OF ZIP9 RESULTED IN ACTIVATION OF THE PROFIBROTIC TRANSFORMING GROWTH FACTOR-BETA SIGNALING PATHWAY THROUGH PROTEIN KINASE B IN HUMAN FIBROBLASTS. IN ADDITION, RADIATION-INDUCED SKIN FIBROSIS WAS ASSOCIATED WITH INCREASED ZINC ACCUMULATION. THE ZINC CHELATOR N,N,N',N'-TETRAKIS(2-PYRIDYLMETHYL)-1,2-ETHYLENEDIAMINE ABROGATED ZIP9-INDUCED ACTIVATION OF THE TRANSFORMING GROWTH FACTOR-BETA SIGNALING PATHWAY AND ATTENUATED RADIATION-INDUCED SKIN FIBROSIS IN A RAT MODEL. IN SUMMARY, OUR FINDINGS ILLUSTRATE EPIGENETIC REGULATION OF ZIP9 AND ITS CRITICAL ROLE IN PROMOTING RADIATION-INDUCED SKIN FIBROSIS. 2020 11 2763 23 EXPRESSION OF THE LEUKEMIC PROGNOSTIC MARKER CD7 IS LINKED TO EPIGENETIC MODIFICATIONS IN CHRONIC MYELOID LEUKEMIA. BACKGROUND: EXPRESSION LEVELS OF THE CELL SURFACE GLYCOPROTEIN, CD7, AND THE SERINE PROTEASE, ELASTASE 2 (ELA2), IN THE LEUKEMIC CELLS OF PATIENTS WITH CHRONIC MYELOID LEUKEMIA (CML) HAVE BEEN ASSOCIATED WITH CLINICAL OUTCOME. HOWEVER, LITTLE IS KNOWN ABOUT THE MECHANISMS THAT UNDERLIE THE VARIABLE EXPRESSION OF THESE GENES IN THE LEUKEMIC CELLS. RESULTS: TO ADDRESS THIS QUESTION, WE COMPARED THE LEVEL OF THEIR EXPRESSION WITH THE DNA METHYLATION AND HISTONE ACETYLATION STATUS OF 5' SEQUENCES OF BOTH GENES IN LEUKEMIC CELL LINES AND PRIMITIVE (LIN-CD34+) LEUKEMIC CELLS FROM CHRONIC PHASE CML PATIENTS. DNA METHYLATION OF THE ELA2 GENE PROMOTER DID NOT CORRELATE WITH ITS EXPRESSION PATTERN IN LIN-CD34+ CELLS FROM CHRONIC PHASE CML PATIENT SAMPLES EVEN THOUGH THERE WAS CLEAR DIFFERENTIAL DNA METHYLATION OF THIS LOCUS IN ELA2-EXPRESSING AND NON-EXPRESSING CELL LINES. IN CONTRAST, WE FOUND A STRONG RELATION BETWEEN CD7 EXPRESSION AND TRANSCRIPTION-PERMISSIVE CHROMATIN MODIFICATIONS, BOTH AT THE LEVEL OF DNA METHYLATION AND HISTONE ACETYLATION WITH EVIDENCE OF HYPOMETHYLATION OF THE CD7 PROMOTER REGION IN THE LIN-CD34+ CELLS FROM CML PATIENTS WITH HIGH CD7 EXPRESSION. CONCLUSION: THESE FINDINGS INDICATE A LINK BETWEEN EPIGENETIC MODIFICATIONS AND CD7 EXPRESSION IN PRIMITIVE CML CELLS. 2010 12 2432 33 EPIGENETIC SILENCING OF MIR-708 ENHANCES NF-KAPPAB SIGNALING IN CHRONIC LYMPHOCYTIC LEUKEMIA. MICRORNAS (MIRNAS) ARE POST-TRANSCRIPTIONAL REGULATORS OF GENE EXPRESSION AND THEIR DEREGULATION IS INVOLVED IN TUMOR DEVELOPMENT. EPIGENETIC GENE SILENCING IN CANCER BY DNA METHYLATION CONTRIBUTES TO THE SILENCING OF TUMOR-SUPPRESSOR GENES, INCLUDING MIRNAS. WE HAVE RECENTLY SHOWN THAT THE PROMOTER OF MIR-708 IS ABERRANTLY METHYLATED IN CHRONIC LYMPHOCYTIC LEUKEMIA (CLL). TO CHARACTERIZE THE MOLECULAR SIGNALING NETWORKS THAT ARE INFLUENCED BY MIR-708, WE PERFORMED A LUCIFERASE-BASED SCREEN EVALUATING THE EFFECTS OF ECTOPIC MIR-708 EXPRESSION ON LEUKEMIA-RELEVANT SIGNALING PATHWAYS. WE FOUND THAT MIR-708 STRONGLY REPRESSED NF-KAPPAB SIGNALING, A PATHWAY KNOWN TO BE DEREGULATED IN CLL. AMONG THE PREDICTED MIR-708 TARGETS WAS IKKBETA (INHIBITOR OF KAPPA LIGHT POLYPEPTIDE GENE ENHANCER IN B CELLS, KINASE-BETA/IKBKB), A KEY KINASE FACILITATING NF-KAPPAB SIGNALING. WE VALIDATED THE INTERACTION OF MIR-708 WITH THE 3'-UNTRANSLATED REGION OF IKKBETA AND FOUND THAT MIR-708 OVEREXPRESSION REPRESSES ENDOGENOUS IKKBETA. PHOSPHORYLATION OF THE IKKBETA TARGET IKAPPABALPHA AND EXPRESSION OF KNOWN NF-KAPPAB TARGET GENES WERE IMPAIRED BY MIR-708. FURTHERMORE, WE IDENTIFIED AN ENHANCER REGION DOWNSTREAM OF THE MIR-708 PROMOTER THAT DISPLAYS A DISTINCT DNA METHYLATION STATUS IN CLL. HIGH ENHANCER METHYLATION IS SIGNIFICANTLY CORRELATED WITH LOWER MIR-708 EXPRESSION AND IS PREDOMINANTLY FOUND IN PATIENTS WITH POOR PROGNOSIS AND SHORTER TIME TO TREATMENT. THESE RESULTS DEMONSTRATE THAT MIR-708 REGULATES THE NF-KAPPAB PATHWAY BY TARGETING IKKBETA, AND THAT METHYLATION OF A KEY ENHANCER REGION CONTRIBUTES TO ITS SUPPRESSION IN CLL. 2015 13 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 14 197 37 ACINAR ATP8B1/LPC PATHWAY PROMOTES MACROPHAGE EFFEROCYTOSIS AND CLEARANCE OF INFLAMMATION DURING CHRONIC PANCREATITIS DEVELOPMENT. NONINFLAMMATORY CLEARANCE OF DYING CELLS BY PROFESSIONAL PHAGOCYTES, TERMED EFFEROCYTOSIS, IS FUNDAMENTAL IN BOTH HOMEOSTASIS AND INFLAMMATORY FIBROSIS DISEASE BUT HAS NOT BEEN CONFIRMED TO OCCUR IN CHRONIC PANCREATITIS (CP). HERE, WE INVESTIGATED WHETHER EFFEROCYTOSIS CONSTITUTES A NOVEL REGULATORY TARGET IN CP AND ITS MECHANISMS. PRSS1 TRANSGENIC (PRSS1(TG)) MICE WERE TREATED WITH CAERULEIN TO MIMIC CP DEVELOPMENT. PHOSPHOLIPID METABOLITE PROFILING AND EPIGENETIC ASSAYS WERE PERFORMED WITH PRSS1(TG) CP MODELS. THE POTENTIAL FUNCTIONS OF ATP8B1 IN CP MODEL WERE CLARIFIED USING ATP8B1-OVEREXPRESSING ADENO-ASSOCIATED VIRUS, IMMUNOFLUORESCENCE, ENZYME-LINKED IMMUNOSORBENT ASSAY(ELISA), AND LIPID METABOLOMIC APPROACHES. ATAC-SEQ COMBINED WITH RNA-SEQ WAS THEN USED TO IDENTIFY TRANSCRIPTION FACTORS BINDING TO THE ATP8B1 PROMOTER, AND CHIP-QPCR AND LUCIFERASE ASSAYS WERE USED TO CONFIRM THAT THE IDENTIFIED TRANSCRIPTION FACTOR BOUND TO THE ATP8B1 PROMOTER, AND TO IDENTIFY THE SPECIFIC BINDING SITE. FLOW CYTOMETRY WAS PERFORMED TO ANALYZE THE PROPORTION OF PANCREATIC MACROPHAGES. DECREASED EFFEROCYTOSIS WITH AGGRAVATED INFLAMMATION WAS IDENTIFIED IN CP. THE LYSOPHOSPHATIDYLCHOLINE (LPC) PATHWAY WAS THE MOST OBVIOUSLY DYSREGULATED PHOSPHOLIPID PATHWAY, AND LPC AND ATP8B1 EXPRESSION GRADUALLY DECREASED DURING CP DEVELOPMENT. H3K27ME3 CHIP-SEQ SHOWED THAT INCREASED ATP8B1 PROMOTER METHYLATION LED TO TRANSCRIPTIONAL INHIBITION. ATP8B1 COMPLEMENTATION SUBSTANTIALLY INCREASED THE LPC CONCENTRATION AND IMPROVED CP OUTCOMES. BHLHA15 WAS IDENTIFIED AS A TRANSCRIPTION FACTOR THAT BINDS TO THE ATP8B1 PROMOTER AND REGULATES PHOSPHOLIPID METABOLISM. OUR STUDY INDICATES THAT THE ACINAR ATP8B1/LPC PATHWAY ACTS AS AN IMPORTANT "FIND-ME" SIGNAL FOR MACROPHAGES AND PLAYS A PROTECTIVE ROLE IN CP, WITH ATP8B1 TRANSCRIPTION PROMOTED BY THE ACINAR CELL-SPECIFIC TRANSCRIPTION FACTOR BHLHA15. BHLHA15, ATP8B1, AND LPC COULD BE CLINICALLY TRANSLATED INTO VALUABLE THERAPEUTIC TARGETS TO OVERCOME THE LIMITATIONS OF CURRENT CP THERAPIES. 2022 15 1334 23 DEREGULATION OF AIOLOS EXPRESSION IN CHRONIC LYMPHOCYTIC LEUKEMIA IS ASSOCIATED WITH EPIGENETIC MODIFICATIONS. CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) IS CHARACTERIZED BY A CLONAL ACCUMULATION OF MATURE NEOPLASTIC B CELLS THAT ARE RESISTANT TO APOPTOSIS. AIOLOS, A MEMBER OF THE IKAROS FAMILY OF ZINC-FINGER TRANSCRIPTION FACTORS, PLAYS AN IMPORTANT ROLE IN THE CONTROL OF MATURE B LYMPHOCYTE DIFFERENTIATION AND MATURATION. IN THIS STUDY, WE SHOWED THAT AIOLOS EXPRESSION IS UP-REGULATED IN B-CLL CELLS. THIS OVEREXPRESSION DOES NOT IMPLICATE ISOFORM IMBALANCE OR DISTURB AIOLOS SUBCELLULAR LOCALIZATION. THE CHROMATIN STATUS AT THE AIOLOS PROMOTER IN CLL IS DEFINED BY THE DEMETHYLATION OF DNA AND AN ENRICHMENT OF EUCHROMATIN ASSOCIATED HISTONE MARKERS, SUCH AS THE DIMETHYLATION OF THE LYSINE 4 ON HISTONE H3. THESE EPIGENETIC MODIFICATIONS SHOULD ALLOW ITS UPSTREAM EFFECTORS, SUCH AS NUCLEAR FACTOR-KAPPAB, CONSTITUTIVELY ACTIVATED IN CLL, TO GAIN ACCESS TO PROMOTER, RESULTING UP-REGULATION OF AIOLOS. TO DETERMINE THE CONSEQUENCES OF AIOLOS DEREGULATION IN CLL, WE ANALYZED THE EFFECTS OF AIOLOS OVEREXPRESSION OR DOWN-REGULATION ON APOPTOSIS. AIOLOS IS INVOLVED IN CELL SURVIVAL BY REGULATING THE EXPRESSION OF SOME BCL-2 FAMILY MEMBERS. OUR RESULTS STRONGLY SUGGEST THAT AIOLOS DEREGULATION BY EPIGENETIC MODIFICATIONS MAY BE A HALLMARK OF CLL. 2011 16 2453 35 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 17 1966 39 EPIGENETIC ALTERATION OF PRKCDBP IN COLORECTAL CANCERS AND ITS IMPLICATION IN TUMOR CELL RESISTANCE TO TNFALPHA-INDUCED APOPTOSIS. PURPOSE: PRKCDBP IS A PUTATIVE TUMOR SUPPRESSOR IN WHICH ALTERATION HAS BEEN OBSERVED IN SEVERAL HUMAN CANCERS. WE INVESTIGATED EXPRESSION AND FUNCTION OF PRKCDBP IN COLORECTAL CELLS AND TISSUES TO EXPLORE ITS CANDIDACY AS A SUPPRESSOR IN COLORECTAL TUMORIGENESIS. EXPERIMENTAL DESIGN: EXPRESSION AND METHYLATION STATUS OF PRKCDBP AND ITS EFFECT ON TUMOR GROWTH WERE EVALUATED. TRANSCRIPTIONAL REGULATION BY NF-KAPPAB SIGNALING WAS DEFINED BY LUCIFERASE REPORTER AND CHROMATIN IMMUNOPRECIPITATION ASSAYS. RESULTS: PRKCDBP EXPRESSION WAS HARDLY DETECTABLE IN 29 OF 80 (36%) PRIMARY TUMORS AND 11 OF 19 (58%) CELL LINES, AND ITS ALTERATION CORRELATED WITH TUMOR STAGE AND GRADE. PROMOTER HYPERMETHYLATION WAS COMMONLY FOUND IN CANCERS. PRKCDBP EXPRESSION INDUCED THE G(1) CELL-CYCLE ARREST AND INCREASED CELLULAR SENSITIVITY TO VARIOUS APOPTOTIC STRESSES. PRKCDBP WAS INDUCED BY TNFALPHA, AND ITS LEVEL CORRELATED WITH TUMOR CELL SENSITIVITY TO TNFALPHA-INDUCED APOPTOSIS. PRKCDBP INDUCTION BY TNFALPHA WAS DISRUPTED BY BLOCKING NF-KAPPAB SIGNALING WHILE IT WAS ENHANCED BY RELA TRANSFECTION. THE PRKCDBP PROMOTER ACTIVITY WAS INCREASED IN RESPONSE TO TNFALPHA, AND THIS RESPONSE WAS ABOLISHED BY DISRUPTION OF A KAPPAB SITE IN THE PROMOTER. PRKCDBP DELAYED THE FORMATION AND GROWTH OF XENOGRAFT TUMORS AND IMPROVED TUMOR RESPONSE TO TNFALPHA-INDUCED APOPTOSIS. CONCLUSIONS: PRKCDBP IS A PROAPOPTOTIC TUMOR SUPPRESSOR WHICH IS COMMONLY ALTERED IN COLORECTAL CANCER BY PROMOTER HYPERMETHYLATION, AND ITS GENE TRANSCRIPTION IS DIRECTLY ACTIVATED BY NF-KAPPAB IN RESPONSE TO TNFALPHA. THIS SUGGESTS THAT PRKCDBP INACTIVATION MAY CONTRIBUTE TO TUMOR PROGRESSION BY REDUCING CELLULAR SENSITIVITY TO TNFALPHA AND OTHER STRESSES, PARTICULARLY UNDER CHRONIC INFLAMMATORY MICROENVIRONMENT. 2011 18 1622 33 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 19 3161 26 GRAINYHEAD-LIKE 2 (GRHL2) INHIBITS KERATINOCYTE DIFFERENTIATION THROUGH EPIGENETIC MECHANISM. WE RECENTLY IDENTIFIED GRAINYHEAD-LIKE 2 (GRHL2), A MAMMALIAN HOMOLOG OF GRAINYHEAD IN DROSOPHILA, TO BE A NOVEL TRANSCRIPTION FACTOR THAT REGULATES HTERT GENE EXPRESSION AND ENHANCES PROLIFERATION OF NORMAL HUMAN EPIDERMAL KERATINOCYTES (NHEK). IN THE CURRENT STUDY, WE SHOW THAT GRHL2 IMPAIRS KERATINOCYTE DIFFERENTIATION THROUGH TRANSCRIPTIONAL INHIBITION OF THE GENES CLUSTERED AT THE EPIDERMAL DIFFERENTIATION COMPLEX (EDC), LOCATED AT CHROMOSOME 1Q21. GENE EXPRESSION PROFILING AND SUBSEQUENT IN VITRO ASSAYS REVEALED CONSISTENT DOWNREGULATION OF EDC GENES, FOR EXAMPLE, IVL, KRT1, FLG, LCES, AND SPRRS, IN NHEK EXPRESSING EXOGENOUS GRHL2. IN VIVO BINDING ASSAY BY CHROMATIN IMMUNOPRECIPITATION REVEALED GRHL2 ASSOCIATION AT THE PROMOTER REGIONS OF ITS TARGET GENES, MANY OF WHICH BELONG TO EDC. EXOGENOUS GRHL2 EXPRESSION ALSO INHIBITED RECRUITMENT OF HISTONE DEMETHYLASE JMJD3 TO THE EDC GENE PROMOTERS AND ENHANCED THE LEVEL OF HISTONE 3 LYS 27 TRIMETHYLATION ENRICHMENT AT THESE PROMOTERS. SURVEY OF GRHL2 EXPRESSION IN HUMAN SKIN TISSUES DEMONSTRATED ENHANCED PROTEIN AND MRNA LEVELS IN CHRONIC SKIN LESIONS WITH IMPAIRED KERATINOCYTE DIFFERENTIATION, FOR EXAMPLE, ATOPIC DERMATITIS AND PSORIASIS, COMPARED WITH NORMAL EPIDERMIS. THESE DATA INDICATE THAT GRHL2 IMPAIRS EPIDERMAL DIFFERENTIATION BY INHIBITING EDC GENE EXPRESSION THROUGH EPIGENETIC MECHANISMS AND SUPPORT ITS ROLE IN THE HYPERPROLIFERATIVE SKIN DISEASES. 2012 20 4001 40 LOSS OF MEN1 LEADS TO RENAL FIBROSIS AND DECREASES HGF-ADAMTS5 PATHWAY ACTIVITY VIA AN EPIGENETIC MECHANISM. BACKGROUND: RENAL FIBROSIS IS A SERIOUS CONDITION THAT RESULTS IN THE DEVELOPMENT OF CHRONIC KIDNEY DISEASES. THE MEN1 GENE IS AN EPIGENETIC REGULATOR THAT ENCODES THE MENIN PROTEIN AND ITS ROLE IN KIDNEY TISSUE REMAINS UNCLEAR. METHODS: KIDNEY HISTOLOGY WAS EXAMINED ON PARAFFIN SECTIONS STAINED WITH HEMATOXYLIN-EOSIN STAINING. MASSON'S TRICHROME STAINING AND SIRIUS RED STAINING WERE USED TO ANALYZE RENAL FIBROSIS. GENE AND PROTEIN EXPRESSION WERE DETERMINED BY QUANTITATIVE REAL-TIME PCR (QPCR) AND WESTERN BLOT, RESPECTIVELY. IMMUNOHISTOCHEMISTRY STAINING IN THE KIDNEY TISSUES FROM MICE OR PATIENTS WAS USED TO EVALUATE PROTEIN LEVELS. FLOW CYTOMETRY WAS USED TO ANALYZE THE CELL CYCLE DISTRIBUTIONS AND APOPTOSIS. RNA-SEQUENCING WAS PERFORMED FOR DIFFERENTIAL EXPRESSION GENES IN THE KIDNEY TISSUES OF THE MEN1F/F AND MEN1?/? MICE. CHROMATIN IMMUNOPRECIPITATION SEQUENCING (CHIP-SEQ) WAS CARRIED OUT FOR IDENTIFICATION OF MENIN- AND H3K4ME3-ENRICHED REGIONS WITHIN THE WHOLE GENOME IN THE MOUSE KIDNEY TISSUE. CHIP-QPCR ASSAYS WERE PERFORMED FOR OCCUPANCY OF MENIN AND H3K4ME3 AT THE GENE PROMOTER REGIONS. LUCIFERASE REPORTER ASSAY WAS USED TO DETECT THE PROMOTER ACTIVITY. THE EXACERBATED UNILATERAL URETERAL OBSTRUCTION (UUO) MODELS IN THE MEN1F/F AND MEN1?/? MICE WERE USED TO ASSESS THE PHARMACOLOGICAL EFFECTS OF RH-HGF ON RENAL FIBROSIS. RESULTS: THE EXPRESSION OF MEN1 IS REDUCE IN KIDNEY TISSUES OF FIBROTIC MOUSE AND HUMAN DIABETIC PATIENTS AND TREATMENT WITH FIBROTIC FACTOR RESULTS IN THE DOWNREGULATION OF MEN1 EXPRESSION IN RENAL TUBULAR EPITHELIAL CELLS (RTECS). DISRUPTION OF MEN1 IN RTECS LEADS TO HIGH EXPRESSION OF ALPHA-SMA AND COLLAGEN 1, WHEREAS MEN1 OVEREXPRESSION RESTRAINS EPITHELIAL-TO-MESENCHYMAL TRANSITION (EMT) INDUCED BY TGF-BETA TREATMENT. CONDITIONAL KNOCKOUT OF MEN1 RESULTED IN CHRONIC RENAL FIBROSIS AND UUO-INDUCED TUBULOINTERSTITIAL FIBROSIS (TIF), WHICH IS ASSOCIATED WITH AN INCREASED INDUCTION OF EMT, G2/M ARREST AND JNK SIGNALING. MECHANISTICALLY, MENIN RECRUITS AND INCREASES H3K4ME3 AT THE PROMOTER REGIONS OF HEPATOCYTE GROWTH FACTOR (HGF) AND A DISINTEGRIN AND METALLOPROTEINASE WITH THROMBOSPONDIN MOTIFS 5 (ADAMTS5) GENES AND ENHANCES THEIR TRANSCRIPTIONAL ACTIVATION. IN THE UUO MICE MODEL, EXOGENOUS HGF RESTORED THE EXPRESSION OF ADAMTS5 AND AMELIORATED RENAL FIBROSIS INDUCED BY MEN1 DEFICIENCY. CONCLUSIONS: THESE FINDINGS DEMONSTRATE THAT MEN1 IS AN ESSENTIAL ANTIFIBROTIC FACTOR IN RENAL FIBROGENESIS AND COULD BE A POTENTIAL TARGET FOR ANTIFIBROTIC THERAPY. 2022