1 5098 144 PLEIOTROPIC EFFECTS OF METHIONINE ADENOSYLTRANSFERASES DEREGULATION AS DETERMINANTS OF LIVER CANCER PROGRESSION AND PROGNOSIS. DOWNREGULATION OF LIVER-SPECIFIC MAT1A GENE, ENCODING S-ADENOSYLMETHIONINE (SAM) SYNTHESIZING ISOZYMES MATI/III, AND UPREGULATION OF WIDELY EXPRESSED MAT2A, ENCODING MATII ISOZYME, KNOWN AS MAT1A:MAT2A SWITCH, OCCURS IN HEPATOCELLULAR CARCINOMA (HCC). BEING INHIBITED BY ITS REACTION PRODUCT, MATII ISOFORM UPREGULATION CANNOT COMPENSATE FOR MATI/III DECREASE. THEREFORE, MAT1A:MAT2A SWITCH CONTRIBUTES TO DECREASE IN SAM LEVEL IN RODENT AND HUMAN HEPATOCARCINOGENESIS. SAM ADMINISTRATION TO CARCINOGEN-TREATED RATS PREVENTS HEPATOCARCINOGENESIS, WHEREAS MAT1A-KO MICE, CHARACTERIZED BY CHRONIC SAM DEFICIENCY, EXHIBIT MACROVESICULAR STEATOSIS, MONONUCLEAR CELL INFILTRATION IN PERIPORTAL AREAS, AND HCC DEVELOPMENT. THIS REVIEW FOCUSES UPON THE PLEIOTROPIC CHANGES, INDUCED BY MAT1A/MAT2A SWITCH, ASSOCIATED WITH HCC DEVELOPMENT. EPIGENETIC CONTROL OF MATS EXPRESSION OCCURS AT TRANSCRIPTIONAL AND POST-TRANSCRIPTIONAL LEVELS. IN HCC CELLS, MAT1A/MAT2A SWITCH IS ASSOCIATED WITH GLOBAL DNA HYPOMETHYLATION, DECREASE IN DNA REPAIR, GENOMIC INSTABILITY, AND SIGNALING DEREGULATION INCLUDING C-MYC OVEREXPRESSION, RISE IN POLYAMINE SYNTHESIS, UPREGULATION OF RAS/ERK, IKK/NF-KB, PI3K/AKT, AND LKB1/AMPK AXIS. FURTHERMORE, DECREASE IN MAT1A EXPRESSION AND SAM LEVELS RESULTS IN INCREASED HCC CELL PROLIFERATION, CELL SURVIVAL, AND MICROVASCULARIZATION. ALL OF THESE CHANGES ARE REVERSED BY SAM TREATMENT IN VIVO OR FORCED MAT1A OVEREXPRESSION OR MAT2A INHIBITION IN CULTURED HCC CELLS. IN HUMAN HCC, MAT1A:MAT2A AND MATI/III:MATII RATIOS CORRELATE NEGATIVELY WITH CELL PROLIFERATION AND GENOMIC INSTABILITY, AND POSITIVELY WITH APOPTOSIS AND GLOBAL DNA METHYLATION. THIS SUGGESTS THAT SAM DECREASE AND MATS DEREGULATION REPRESENT POTENTIAL THERAPEUTIC TARGETS FOR HCC. FINALLY, MATI/III:MATII RATIO STRONGLY PREDICTS PATIENTS' SURVIVAL LENGTH SUGGESTING THAT MAT1A:MAT2A EXPRESSION RATIO IS A PUTATIVE PROGNOSTIC MARKER FOR HUMAN HCC. 2013 2 3128 35 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 3 1067 41 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 4 1334 36 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 5 4233 38 METHYLATION OF SEPTIN9 MEDIATED BY DNMT3A ENHANCES HEPATIC STELLATE CELLS ACTIVATION AND LIVER FIBROGENESIS. LIVER FIBROSIS, RESULTING FROM CHRONIC AND PERSISTENT INJURY TO THE LIVER, IS A WORLDWIDE HEALTH PROBLEM. ADVANCED LIVER FIBROSIS RESULTS IN CIRRHOSIS, LIVER FAILURE AND EVEN HEPATOCELLULAR CANCER (HCC), OFTEN EVENTUALLY REQUIRING LIVER TRANSPLANTATION, POSES A HUGE HEALTH BURDEN ON THE GLOBAL COMMUNITY. HOWEVER, THE SPECIFIC PATHOGENESIS OF LIVER FIBROSIS REMAINS NOT FULLY UNDERSTOOD. NUMEROUS BASIC AND CLINICAL STUDIES HAVE PROVIDED EVIDENCE THAT EPIGENETIC MODIFICATIONS, ESPECIALLY DNA METHYLATION, MIGHT CONTRIBUTE TO THE ACTIVATION OF HEPATIC STELLATE CELLS (HSCS), THE PIVOTAL CELL TYPE RESPONSIBLE FOR THE FIBROUS SCAR IN LIVER. HERE, REDUCED REPRESENTATION BISULFITE SEQUENCING (RRBS) AND BISULFITE PYROSEQUENCING PCR (BSP) ANALYSIS IDENTIFIED HYPERMETHYLATION STATUS OF SEPTIN9 (SEPT9) GENE IN LIVER FIBROGENESIS. SEPT9 PROTEIN WAS DRAMATICALLY DECREASED IN LIVERS OF CCL4-TREATED MICE AND IMMORTALIZED HSC-T6 CELLS EXPOSED TO TGF-BETA1. NEVERTHELESS, THE SUPPRESSION OF SEPT9 COULD BE BLOCKED BY DNMT3A-SIRNA AND DNA METHYLTRANSFERASE INHIBITOR, 5-AZA-2'-DEOXYCYTIDINE (5-AZADC). OVEREXPRESSED SEPT9 ATTENUATED TGF-BETA1-INDUCED EXPRESSION OF MYOFIBROBLAST MARKERS ALPHA-SMA AND COL1A1, ACCOMPANIED BY UP-REGULATION OF CELL APOPTOSIS-RELATED PROTEINS. CONVERSELY, RNAI-MEDIATED SILENCING OF SEPT9 ENHANCED ACCUMULATION OF EXTRACELLULAR MATRIX. THESE OBSERVATIONS SUGGESTED THAT SEPT9 CONTRIBUTED TO ALLEVIATE LIVER FIBROSIS MIGHT PARTIALLY THROUGH PROMOTING ACTIVATED HSCS APOPTOSIS AND THIS ANTI-FIBROGENESIS EFFECT MIGHT BE BLOCKED BY DNMT-3A MEDIATED METHYLATION OF SEPT9. THEREFORE, PHARMACOLOGICAL AGENTS THAT INHIBIT SEPT9 METHYLATION AND INCREASE ITS EXPRESSION COULD BE CONSIDERED AS VALUABLE TREATMENTS FOR LIVER FIBROSIS. 2017 6 3049 28 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 7 136 30 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 8 3327 36 HISTONE DEACETYLASE 4 PROMOTES CHOLESTATIC LIVER INJURY IN THE ABSENCE OF PROHIBITIN-1. PROHIBITIN-1 (PHB1) IS AN EVOLUTIONARILY CONSERVED PLEIOTROPIC PROTEIN THAT PARTICIPATES IN DIVERSE PROCESSES DEPENDING ON ITS SUBCELLULAR LOCALIZATION AND INTERACTOME. RECENT DATA HAVE INDICATED A DIVERSE ROLE FOR PHB1 IN THE PATHOGENESIS OF OBESITY, CANCER, AND INFLAMMATORY BOWEL DISEASE, AMONG OTHERS. DATA PRESENTED HERE SUGGEST THAT PHB1 IS ALSO LINKED TO CHOLESTATIC LIVER DISEASE. EXPRESSION OF PHB1 IS MARKEDLY REDUCED IN PATIENTS WITH PRIMARY BILIARY CIRRHOSIS AND BILIARY ATRESIA OR WITH ALAGILLE SYNDROME, TWO MAJOR PEDIATRIC CHOLESTATIC CONDITIONS. IN THE EXPERIMENTAL MODEL OF BILE DUCT LIGATION, SILENCING OF PHB1 INDUCED LIVER FIBROSIS, REDUCED ANIMAL SURVIVAL, AND INDUCED BILE DUCT PROLIFERATION. IMPORTANTLY, THE MODULATORY EFFECT OF PHB1 IS NOT DEPENDENT ON ITS KNOWN MITOCHONDRIAL FUNCTION. ALSO, PHB1 INTERACTS WITH HISTONE DEACETYLASE 4 (HDAC4) IN THE PRESENCE OF BILE ACIDS. HENCE, PHB1 DEPLETION LEADS TO INCREASED NUCLEAR HDAC4 CONTENT AND ITS ASSOCIATED EPIGENETIC CHANGES. REMARKABLY, HDAC4 SILENCING AND THE ADMINISTRATION OF THE HDAC INHIBITOR PARTHENOLIDE DURING OBSTRUCTIVE CHOLESTASIS IN VIVO PROMOTE GENOMIC REPROGRAMMING, LEADING TO REGRESSION OF THE FIBROTIC PHENOTYPE IN LIVER-SPECIFIC PHB1 KNOCKOUT MICE. CONCLUSION: PHB1 IS AN IMPORTANT MEDIATOR OF CHOLESTATIC LIVER INJURY THAT REGULATES THE ACTIVITY OF HDAC4, WHICH CONTROLS SPECIFIC EPIGENETIC MARKERS; THESE RESULTS IDENTIFY POTENTIAL NOVEL STRATEGIES TO TREAT LIVER INJURY AND FIBROSIS, PARTICULARLY AS A CONSEQUENCE OF CHRONIC CHOLESTASIS. 2015 9 6659 34 UPREGULATION OF AKT3 CONFERS RESISTANCE TO THE AKT INHIBITOR MK2206 IN BREAST CANCER. ACQUIRED RESISTANCE TO MOLECULAR TARGETED THERAPY REPRESENTS A MAJOR CHALLENGE FOR THE EFFECTIVE TREATMENT OF CANCER. HYPERACTIVATION OF THE PI3K/AKT PATHWAY IS FREQUENTLY OBSERVED IN VIRTUALLY ALL HUMAN MALIGNANCIES, AND NUMEROUS PI3K AND AKT INHIBITORS ARE CURRENTLY UNDER CLINICAL EVALUATION. HOWEVER, MECHANISMS OF ACQUIRED RESISTANCE TO AKT INHIBITORS HAVE YET TO BE DESCRIBED. HERE, WE USE A BREAST CANCER PRECLINICAL MODEL TO IDENTIFY RESISTANCE MECHANISMS TO A SMALL MOLECULE ALLOSTERIC AKT INHIBITOR, MK2206. USING A STEP-WISE AND CHRONIC HIGH-DOSE EXPOSURE, BREAST CANCER CELL LINES HARBORING ONCOGENIC PI3K RESISTANT TO MK2206 WERE ESTABLISHED. USING THIS MODEL, WE REVEAL THAT AKT3 EXPRESSION IS MARKEDLY UPREGULATED IN AKT INHIBITOR-RESISTANT CELLS. INDUCTION OF AKT3 IS REGULATED EPIGENETICALLY BY THE BROMODOMAIN AND EXTRA TERMINAL DOMAIN PROTEINS. IMPORTANTLY, KNOCKDOWN OF AKT3, BUT NOT AKT1 OR AKT2, IN RESISTANT CELLS RESTORES SENSITIVITY TO MK2206. AKT INHIBITOR-RESISTANT CELLS ALSO DISPLAY AN EPITHELIAL TO MESENCHYMAL TRANSITION PHENOTYPE AS ASSESSED BY ALTERATIONS IN THE LEVELS OF E-CADHERIN, N-CADHERIN, AND VIMENTIN, AS WELL AS ENHANCED INVASIVENESS OF TUMOR SPHEROIDS. NOTABLY, THE INVASIVE MORPHOLOGY OF RESISTANT SPHEROIDS IS DIMINISHED UPON AKT3 DEPLETION. WE ALSO SHOW THAT RESISTANCE TO MK2206 IS REVERSIBLE BECAUSE UPON DRUG REMOVAL RESISTANT CELLS REGAIN SENSITIVITY TO AKT INHIBITION, ACCOMPANIED BY REEXPRESSION OF EPITHELIAL MARKERS AND REDUCTION OF AKT3 EXPRESSION, IMPLYING THAT EPIGENETIC REPROGRAMMING CONTRIBUTES TO ACQUISITION OF RESISTANCE. THESE FINDINGS PROVIDE A RATIONALE FOR DEVELOPING THERAPEUTICS TARGETING AKT3 TO CIRCUMVENT ACQUIRED RESISTANCE IN BREAST CANCER. MOL CANCER THER; 15(8); 1964-74. (C)2016 AACR. 2016 10 5004 28 PERIPHERAL B CELLS FROM PATIENTS WITH HEPATITIS C VIRUS-ASSOCIATED LYMPHOMA EXHIBIT CLONAL EXPANSION AND AN ANERGIC-LIKE TRANSCRIPTIONAL PROFILE. CHRONIC HCV INFECTION REMAINS A GLOBAL HEALTH CONCERN DUE TO ITS INVOLVEMENT IN HEPATIC AND EXTRAHEPATIC DISEASES, INCLUDING B CELL NON-HODGKIN LYMPHOMA (BNHL). CLINICAL AND EPIDEMIOLOGICAL EVIDENCE SUPPORT A CAUSAL ROLE FOR HCV IN BNHL DEVELOPMENT, ALTHOUGH MECHANISTIC INSIGHT IS LACKING. WE PERFORMED RNA-SEQUENCING ON PERIPHERAL B CELLS FROM PATIENTS WITH HCV ALONE, BNHL ALONE, AND HCV-ASSOCIATED BNHL TO IDENTIFY UNIQUE AND SHARED TRANSCRIPTIONAL PROFILES ASSOCIATED WITH TRANSFORMATION. IN PATIENTS WITH HCV-ASSOCIATED BNHL, WE OBSERVED THE ENRICHMENT OF AN ANERGIC-LIKE GENE SIGNATURE AND EVIDENCE OF CLONAL EXPANSION THAT WAS CORRELATED WITH THE EXPRESSION OF EPIGENETIC REGULATORY GENES. OUR DATA SUPPORT A ROLE FOR VIRAL-MEDIATED CLONAL EXPANSION OF ANERGIC-LIKE B CELLS IN HCV-ASSOCIATED BNHL DEVELOPMENT AND SUGGEST EPIGENETIC DYSREGULATION AS A POTENTIAL MECHANISM DRIVING EXPANSION. WE PROPOSE EPIGENETIC MECHANISMS MAY BE INVOLVED IN BOTH HCV-ASSOCIATED LYMPHOMA AND REGULATION OF B CELL ANERGY, REPRESENTING AN ATTRACTIVE TARGET FOR CLINICAL INTERVENTIONS. 2023 11 2763 32 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 12 155 35 ABERRANT METHYLATION OF POLO-LIKE KINASE CPG ISLANDS IN PLK4 HETEROZYGOUS MICE. BACKGROUND: HEPATOCELLULAR CARCINOMA (HCC), ONE OF THE MOST COMMON CANCERS WORLD-WIDE OCCURS TWICE AS OFTEN IN MEN COMPARED TO WOMEN. PREDISPOSING CONDITIONS SUCH AS ALCOHOLISM, CHRONIC VIRAL HEPATITIS, AFLATOXIN B1 INGESTION, AND CIRRHOSIS ALL CONTRIBUTE TO THE DEVELOPMENT OF HCC. METHODS: WE USED A COMBINATION OF METHYLATION SPECIFIC PCR AND BISULFITE SEQUENCING, QREAL-TIME PCR (QPCR), AND WESTERN BLOT ANALYSIS TO EXAMINE EPIGENETIC CHANGES FOR THE POLO-LIKE KINASES (PLKS) DURING THE DEVELOPMENT OF HEPATOCELLULAR CARCINOMA (HCC) IN PLK4 HETEROZYGOUS MICE AND MURINE EMBRYONIC FIBROBLASTS (MEFS). RESULTS: HERE WE REPORT THAT THE PROMOTER METHYLATION OF PLK4 CPG ISLANDS INCREASES WITH AGE, WAS MORE PREVALENT IN MALES AND THAT PLK4 EPIGENETIC MODIFICATION AND SUBSEQUENT DOWNREGULATION OF EXPRESSION WAS ASSOCIATED WITH THE DEVELOPMENT OF HCC IN PLK4 MUTANT MICE. INTERESTINGLY, THE OPPOSITE OCCURS WITH ANOTHER PLK FAMILY MEMBER, PLK1 WHICH WAS TYPICALLY HYPERMETHYLATED IN NORMAL LIVER TISSUE BUT BECAME HYPOMETHYLATED AND UPREGULATED IN LIVER TUMOURS. FURTHERMORE, UPON ALCOHOL EXPOSURE MURINE EMBRYONIC FIBROBLASTS EXHIBITED INCREASED PLK4 HYPERMETHYLATION AND DOWNREGULATION ALONG WITH INCREASED CENTROSOME NUMBERS AND MULTINUCLEATION. CONCLUSIONS: THESE RESULTS SUGGEST THAT ABERRANT PLK METHYLATION IS CORRELATED WITH THE DEVELOPMENT OF HCC IN MICE. 2011 13 2432 41 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 14 2316 36 EPIGENETIC REGULATION OF FRUCTOSE-1,6-BISPHOSPHATASE 1 BY HOST TRANSCRIPTION FACTOR SPECKLED 110 KDA DURING HEPATITIS B VIRUS INFECTION. HEPATITIS B VIRUS (HBV) IS THE LEADING CAUSE OF LIVER DISEASE RANGING FROM ACUTE AND CHRONIC HEPATITIS TO LIVER CIRRHOSIS AND HEPATOCELLULAR CARCINOMA (HCC). STUDIES HAVE REVEALED THAT HBV INFECTION BROADLY REPROGRAMMES THE HOST CELLULAR METABOLIC PROCESSES FOR VIRAL PATHOGENESIS. PREVIOUS REPORTS HAVE SHOWN THAT GLYCOLYSIS AND GLUCONEOGENESIS ARE AMONG THE MOST DEREGULATED PATHWAYS DURING HBV INFECTION. WE NOTED THAT DESPITE BEING ONE OF THE RATE-LIMITING ENZYMES OF GLUCONEOGENESIS, THE ROLE AND REGULATION OF FRUCTOSE-1,6-BISPHOSPHATASE 1 (FBP1) DURING HBV INFECTION IS NOT MUCH EXPLORED. IN THIS STUDY, WE REPORT FBP1 UPREGULATION UPON HBV INFECTION AND UNRAVEL A NOVEL MECHANISM OF EPIGENETIC REPROGRAMMING OF FBP1 BY HBV VIA UTILIZING HOST FACTOR SPECKLED 110 KDA (SP110). HERE, WE IDENTIFIED ACETYLATED LYSINE 18 OF HISTONE H3 (H3K18AC) AS A SELECTIVE INTERACTOR OF SP110 BROMODOMAIN. FURTHERMORE, WE FOUND THAT SP110 GETS RECRUITED ON H3K18AC-ENRICHED FBP1 PROMOTER, AND FACILITATES RECRUITMENT OF DEACETYLASE SIRTUIN 2 (SIRT2) ON THAT SITE IN THE PRESENCE OF HBV. SIRT2 IN TURN BRINGS ITS INTERACTOR AND TRANSCRIPTIONAL ACTIVATOR HEPATOCYTE NUCLEAR FACTOR 4-ALPHA TO THE PROMOTER, WHICH ULTIMATELY LEADS TO A LOSS OF DNA METHYLATION NEAR THE COGNATE SITE. INTERESTINGLY, THIS SP110 DRIVEN FBP1 REGULATION DURING INFECTION WAS FOUND TO PROMOTE VIRAL-BORNE HCC PROGRESSION. MOREOVER, SP110 CAN BE USED AS A PROGNOSTIC MARKER FOR THE HEPATITIS-MEDIATED HCC PATIENTS, WHERE HIGH SP110 EXPRESSION SIGNIFICANTLY LOWERED THEIR SURVIVAL. THUS, THE EPIGENETIC READER PROTEIN SP110 HAS POTENTIAL TO BE A THERAPEUTIC TARGET TO CHALLENGE HBV-INDUCED HCCS. 2022 15 4225 26 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 16 5101 34 POLYCOMB FACTOR PHF19 CONTROLS CELL GROWTH AND DIFFERENTIATION TOWARD ERYTHROID PATHWAY IN CHRONIC MYELOID LEUKEMIA CELLS. POLYCOMB GROUP (PCG) OF PROTEINS ARE A GROUP OF HIGHLY CONSERVED EPIGENETIC REGULATORS INVOLVED IN MANY BIOLOGICAL FUNCTIONS, SUCH AS EMBRYONIC DEVELOPMENT, CELL PROLIFERATION, AND ADULT STEM CELL DETERMINATION. PHD FINGER PROTEIN 19 (PHF19) IS AN ASSOCIATED FACTOR OF POLYCOMB REPRESSOR COMPLEX 2 (PRC2), OFTEN UPREGULATED IN HUMAN CANCERS. IN PARTICULAR, MYELOID LEUKEMIA CELL LINES SHOW INCREASED LEVELS OF PHF19, YET LITTLE IS KNOWN ABOUT ITS FUNCTION. HERE, WE HAVE CHARACTERIZED THE ROLE OF PHF19 IN MYELOID LEUKEMIA CELLS. WE DEMONSTRATED THAT PHF19 DEPLETION DECREASES CELL PROLIFERATION AND PROMOTES CHRONIC MYELOID LEUKEMIA (CML) DIFFERENTIATION. MECHANISTICALLY, WE HAVE SHOWN HOW PHF19 REGULATES THE PROLIFERATION OF CML THROUGH A DIRECT REGULATION OF THE CELL CYCLE INHIBITOR P21. FURTHERMORE, WE OBSERVED THAT MTF2, A PHF19 HOMOLOG, PARTIALLY COMPENSATES FOR PHF19 DEPLETION IN A SUBSET OF TARGET GENES, INSTRUCTING SPECIFIC ERYTHROID DIFFERENTIATION. TAKEN TOGETHER, OUR RESULTS SHOW THAT PHF19 IS A KEY TRANSCRIPTIONAL REGULATOR FOR CELL FATE DETERMINATION AND COULD BE A POTENTIAL THERAPEUTIC TARGET FOR MYELOID LEUKEMIA TREATMENT. 2021 17 6385 39 THE ROLE OF PROMYELOCYTIC LEUKEMIA PROTEIN IN STEATOSIS-ASSOCIATED HEPATIC TUMORS RELATED TO CHRONIC HEPATITIS B VIRUS INFECTION. THE PERSISTENCE OF HEPATITIS B SURFACE ANTIGEN (HBSAG) IS A RISK FACTOR FOR THE DEVELOPMENT OF STEATOSIS-ASSOCIATED TUMORS IN CHRONIC HEPATITIS B VIRUS (HBV) INFECTION, YET LITTLE IS KNOWN ABOUT THE METABOLIC LINK WITH THIS FACTOR. WE CORRELATED HBV-RELATED PATHOGENESIS IN GENETICALLY ENGINEERED MICE AND HUMAN CARRIERS WITH METABOLIC PROTEOMICS AND LIPOGENIC GENE EXPRESSION PROFILES. THE IMMUNOHISTOCHEMISTRY SHOWED THAT THE PROMYELOCYTIC LEUKEMIA PROTEIN (PML, A TUMOR SUPPRESSOR INVOLVED IN GENOME MAINTENANCE AND FATTY ACID OXIDATION), BEING INVERSELY INFLUENCED BY THE DYNAMIC HBSAG LEVELS FROM ACUTE PHASE TO SEROCLEARANCE, APPEARED AS A LIPO-METABOLIC SWITCH LINKING HBSAG-INDUCED STEATOSIS (LIPOGENESIS) TO HBSAG-LOST FAT-BURNING HEPATOCARCINOGENESIS (LIPOLYSIS). KNOCKDOWN OF PML IN HBSAG-TRANSGENIC MICE PREDISPOSED TO OBESITY AND DROVE EARLY STEATOSIS-SPECIFIC LIVER TUMORIGENESIS. PROTEOME ANALYSIS REVEALED THAT THE SIGNALING PATHWAYS CORRESPONDING TO ENERGY METABOLISM AND ITS REGULATORS WERE FREQUENTLY ALTERED BY SUPPRESSION OR DEPLETION OF PML IN THE HBSAG-TRANSGENIC MICE, MAINLY INCLUDING OXIDATIVE PHOSPHORYLATION AND FATTY ACID METABOLISM. EXPRESSION PROFILING FURTHER IDENTIFIED UPREGULATION OF STEAROYL-COA DESATURASE 1 (SCD1) AND EPIGENETIC METHYLATION OF NDUFA13 IN THE MITOCHONDRIAL RESPIRATORY CHAIN AND THE CELL CYCLE INHIBITOR CDKN1C IN CONCORDANCE TO THE INCREASED SEVERITY OF LIPODYSTROPHY AND NEOPLASIA IN THE LIVERS OF HBSAG-TRANSGENIC MICE WITH PML INSUFFICIENCY. THE DEFECT IN LIPOLYSIS IN PML-DEFICIENT HBSAG-TRANSGENIC MICE MADE THE HBSAG-INDUCED ADIPOSE-LIKE LIVER TUMORS VULNERABLE TO SYNTHETIC LETHALITY FROM TOXIC SATURATED FAT ACCUMULATION WITH A SCD1 INHIBITOR. OUR FINDINGS PROVIDE MECHANISTIC INSIGHTS INTO THE EVOLUTION OF STEATOSIS-ASSOCIATED HEPATIC TUMORS DRIVEN BY RECIPROCAL INTERACTIONS OF HBSAG AND PML, AND A POTENTIAL UTILITY OF LIPID METABOLIC REPROGRAMMING AS A TREATMENT TARGET. 2018 18 1966 34 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 19 3476 41 IDENTIFICATION OF A TRANSMEMBRANE PROTEIN INVOLVED IN SHEAR STRESS SIGNALING AND HEPATOCARCINOGENESIS AFTER A SUSTAINED VIROLOGICAL RESPONSE TO HEPATITIS C VIRUS. BACKGROUND & AIMS: THE RISK OF HEPATOCELLULAR CARCINOMA (HCC) REMAINS AFTER ACHIEVING A SUSTAINED VIROLOGICAL RESPONSE (SVR) IN PATIENTS WITH CHRONIC HEPATITIS C (CHC). EPIGENETIC ABNORMALITIES MIGHT BE KEY REGULATORS IN THE DEVELOPMENT OF HCC. THIS STUDY AIMED TO IDENTIFY THE GENES INVOLVED IN HEPATOCARCINOGENESIS AFTER AN SVR. METHODS: DNA METHYLATION IN LIVER TISSUE WAS COMPARED BETWEEN 21 CHC PATIENTS WITHOUT HCC AND 28 CHC PATIENTS WITH HCC, ALL OF WHOM HAD ACHIEVED AN SVR. ADDITIONAL COMPARISONS WITH 23 CHC PATIENTS BEFORE TREATMENT AND 10 NORMAL LIVERS WERE PERFORMED. THE CHARACTERISTICS OF A NEWLY IDENTIFIED GENE WERE EXPLORED IN VITRO AND IN VIVO. RESULTS: WE FOUND THAT THE TRANSMEMBRANE PROTEIN NO. 164 (TMEM164) GENE WAS DEMETHYLATED BY HEPATITIS C VIRUS INFECTION AND HCC DEVELOPMENT AFTER ACHIEVING AN SVR. TMEM164 WAS EXPRESSED MAINLY IN ENDOTHELIAL CELLS, ALPHA SMOOTH MUSCLE ACTIN-POSITIVE CELLS, AND SOME CAPILLARIZED LIVER SINUSOIDAL ENDOTHELIAL CELLS. TMEM164 EXPRESSION WAS SIGNIFICANTLY CORRELATED WITH LIVER FIBROSIS AND RELAPSE-FREE SURVIVAL IN HCC PATIENTS. TMEM164 WAS INDUCED BY SHEAR STRESS, INTERACTED WITH GRP78/BIP, ACCELERATED ATF6 (ACTIVATING TRANSCRIPTION FACTOR 6)-MEDIATED ENDOPLASMIC RETICULUM (ER) STRESS SIGNALING, AND ACTIVATED INTERLEUKIN-6/STAT3 (SIGNAL TRANSDUCER AND ACTIVATOR OF TRANSCRIPTION 3) SIGNALING IN THE TMNK1 LIVER ENDOTHELIAL CELL LINE. THEREFORE, WE TERMED TMEM164 "SHEAR STRESS-INDUCED TRANSMEMBRANE PROTEIN ASSOCIATED WITH ER STRESS SIGNALING" (SHERMER). SHERMER KNOCKOUT MICE WERE PROTECTED AGAINST CCL4-INDUCED LIVER FIBROSIS. SHERMER OVEREXPRESSION IN TMNK1 CELLS ACCELERATED HCC GROWTH IN A XENOGRAFT MODEL. CONCLUSIONS: WE IDENTIFIED A NEW TRANSMEMBRANE PROTEIN, SHERMER, IN CHC PATIENTS WITH HCC AFTER ACHIEVING AN SVR. SHERMER WAS INDUCED BY SHEAR STRESS AND ACCELERATED ATF6-MEDIATED ER STRESS SIGNALING IN ENDOTHELIAL CELLS. THUS, SHERMER IS A NOVEL ENDOTHELIAL MARKER ASSOCIATED WITH LIVER FIBROSIS, HEPATOCARCINOGENESIS, AND PROGRESSION OF HCC. 2023 20 3237 32 HEPATIC COX-2 EXPRESSION PROTECTS MICE FROM AN ALCOHOL-HIGH FAT DIET-INDUCED METABOLIC DISORDER BY INVOLVING PROTEIN ACETYLATION RELATED ENERGY METABOLISM. PURPOSE: A DIET HIGH IN FAT AND ETHANOL OFTEN RESULTS IN CHRONIC METABOLIC DISORDER, HEPATIC STEATOSIS, AND LIVER INFLAMMATION. CONSTITUTIVE HEPATIC CYCLOOXYGENASE-2 (COX-2) EXPRESSION COULD PROTECT FROM HIGH FAT-INDUCED METABOLISM DISTURBANCE IN A MURINE MODEL. IN THIS STUDY, WE EXPLORED THE INFLUENCE OF HCOX-2 TRANSGENIC [TG] TO HIGH FAT WITH ETHANOL-INDUCED METABOLIC DISORDER AND LIVER INJURY USING A MOUSE ANIMAL MODEL. METHODS: 12-WEEK-OLD MALE HEPATIC HCOX-2 TRANSGENIC (TG) OR WILD TYPE MICE (WT) WERE FED EITHER A HIGH FAT AND ETHANOL LIQUID DIET (HF+ETH) OR A REGULAR CONTROL DIET (RCD) FOR 5 WEEKS (FOUR GROUPS: RCD/WT, RCD/TG; HF+ETH/TG, HF+ETH/WT). WE ASSESSED METABOLIC BIOMARKERS, CYTOKINE PROFILES, HISTOMORPHOLOGY, AND GENE EXPRESSION TO STUDY THE IMPACT OF PERSISTENT HEPATIC COX-2 EXPRESSION ON DIET-INDUCED LIVER INJURY. RESULTS: IN THE HF+ETH DIET, CONSTITUTIVELY HEPATIC HUMAN COX-2 EXPRESSION PROTECTS MICE FROM BODY WEIGHT GAIN AND WHITE ADIPOSE TISSUE ACCUMULATION, ACCOMPANIED BY IMPROVED IPGTT RESPONSE, SERUM TRIGLYCERIDE/CHOLESTEROL LEVELS, AND LOWER LEVELS OF SERUM AND LIVER INFLAMMATORY CYTOKINES. HISTOLOGICALLY, HCOX-2 MICE SHOWED DECREASED HEPATIC LIPID DROPLETS ACCUMULATION, DECREASED HEPATOCYTE BALLOONING, AND IMPROVED STEATOSIS SCORES. HEPATIC HCOX-2 OVEREXPRESSION ENHANCED AKT INSULIN SIGNALING AND INCREASED FATTY ACID SYNTHESIS IN BOTH RCD AND HF+ETH DIET GROUPS. THE ANTI-LIPOGENIC EFFECT OF HCOX-2 TG IN THE HF+ETH DIET ANIMALS WAS MEDIATED BY INCREASING LIPID DISPOSAL THROUGH ENHANCED BETA-OXIDATION VIA ELEVATIONS IN THE EXPRESSION OF PPARALPHA AND PPARGAMMA, AND INCREASED HEPATIC AUTOPHAGY AS ASSESSED BY THE RATIO OF AUTOPHAGY MARKERS LC3 II/I IN HEPATIC TISSUE. VARIOUS PROTEIN ACETYLATION PATHWAY COMPONENTS, INCLUDING HAT, HDAC1, SIRT1, AND SNAIL1, WERE MODULATED IN HCOX-2 TG MICE IN EITHER RCD OR HF+ETH DIET. CONCLUSIONS: HEPATIC HUMAN COX-2 EXPRESSION PROTECTED MICE FROM THE METABOLIC DISORDER AND LIVER INJURY INDUCED BY A HIGH FAT AND ETHANOL DIET BY ENHANCING HEPATIC LIPID EXPENDITURE. EPIGENETIC REPROGRAMMING OF DIVERSE METABOLIC GENES MIGHT BE INVOLVED IN THE ANTI-LIPOGENIC EFFECT OF COX-2. 2021