1 5850 145 SUBEROYLANILIDE HYDROXAMIC ACID (SAHA) REDUCES FIBROSIS MARKERS AND DEACTIVATES HUMAN STELLATE CELLS VIA THE EPITHELIAL-MESENCHYMAL TRANSITION (EMT). HEPATIC FIBROSIS IS KNOWN AS THE ACCUMULATION OF CONNECTIVE TISSUE SECONDARY TO CHRONIC DAMAGE TO THE LIVER. EPITHELIAL-MESENCHYMAL TRANSITION (EMT) CORRESPONDING INCREASE IN LIVER FIBROGENESIS WAS SHOWN WITH IMMUNOHISTOCHEMISTRY AND PCR-BASED STUDIES. SUBEROYLANILIDE HYDROXAMIC ACID (SAHA), A SYNTHETIC COMPOUND APPROVED AS A HISTONE DEACETYLASE INHIBITOR (HDAC) BY THE FDA TO TREAT CUTANEOUS T-CELL LYMPHOMA IS UNDER INVESTIGATION FOR THE TREATMENT OF LUNG AND RENAL FIBROSIS. EXPERIMENTAL MODELING FOR HEPATIC FIBROSIS CAN BE CONSTRUCTED WITH AN LX2 CELL LINE ISOLATED FROM HUMAN HEPATIC STELLATE CELLS (HSCS). IN THIS STUDY, WE AIMED TO INVESTIGATE THE MODULATION OF SAHA IN THE PATHOGENESIS OF LIVER FIBROSIS BY DETECTING THE LEVELS OF PROTEINS; (E-CADHERIN (E-CAD), N-CADHERIN (N-CAD), VIMENTIN (VIM), AND GENES; E-CAD, N-CAD, VIM, TRANSFORMING GROWTH FACTOR-BETA (TGF-BETA), ALPHA-SMOOTH MUSCLE ACTIN (ALPHA-SMA), TYPE 1 COLLAGEN (COL1A1), TYPE 3 COLLAGEN (COL3A1)) THAT PLAY A SIGNIFICANT ROLE IN EMT WITH THE LX2 CELL LINE. WE ALSO EVALUATED THE ACTION OF SAHA WITH CELL PROLIFERATION, CLONOGENIC, AND MIGRATION ASSAY. CELL PROLIFERATION WAS PERFORMED BY FLOW CYTOMETRY. ALL THE PROTEIN LEVELS WERE DETERMINED BY WESTERN BLOT ANALYSIS, AND GENE EXPRESSION LEVELS WERE MEASURED BY REAL-TIME PCR. OUR STUDY OBSERVED THAT SAHA TREATMENT DECREASED CELL VIABILITY, COLONY FORMATION AND MIGRATION IN LX2 CELLS. WE FOUND THAT SAHA INCREASED E-CAD EXPRESSION LEVEL, WHILE IT DECREASED N-CAD, VIM, COL1A1, COL3A1, ALPHA-SMA TGF-BETA GENES EXPRESSION LEVELS. SAHA DECREASED THE LEVEL OF E-CAD, N-CAD, AND VIM PROTEIN LEVELS. WE THOUGHT THAT SAHA POSSESSES POTENT ANTIFIBROTIC AND ANTI-EMT PROPERTIES IN LX2. 2021 2 3944 45 LNCRNA H19-EZH2 INTERACTION PROMOTES LIVER FIBROSIS VIA REPROGRAMMING H3K27ME3 PROFILES. LIVER FIBROSIS IS A WOUND-HEALING PROCESS CHARACTERIZED BY EXCESS FORMATION OF EXTRACELLULAR MATRIX (ECM) FROM ACTIVATED HEPATIC STELLATE CELLS (HSCS). PREVIOUS STUDIES SHOW THAT BOTH EZH2, AN EPIGENETIC REGULATOR THAT CATALYZES LYSINE 27 TRIMETHYLATION ON HISTONE 3 (H3K27ME3), AND LONG NON-CODING RNA H19 ARE HIGHLY CORRELATED WITH FIBROGENESIS. IN THE CURRENT STUDY, WE INVESTIGATED THE UNDERLYING MECHANISMS. VARIOUS MODELS OF LIVER FIBROSIS INCLUDING MDR2(-/-), BILE DUCT LIGATION (BDL) AND CCL(4) MICE WERE ADAPTED. WE FOUND THAT EZH2 WAS MARKEDLY UPREGULATED AND CORRELATED WITH H19 AND FIBROTIC MARKERS EXPRESSION IN THESE MODELS. ADMINISTRATION OF EZH2 INHIBITOR 3-DZNEP CAUSED SIGNIFICANT PROTECTIVE EFFECTS IN THESE MODELS. FURTHERMORE, TREATMENT WITH 3-DZNEP OR GSK126 SIGNIFICANTLY INHIBITED PRIMARY HSC ACTIVATION AND PROLIFERATION IN TGF-BETA-TREATED HSCS AND H19-OVEREXPREESING LX2 CELLS IN VIVO. USING RNA-PULL DOWN ASSAY COMBINED WITH RNA IMMUNOPRECIPITATION, WE DEMONSTRATED THAT H19 COULD DIRECTLY BIND TO EZH2. INTEGRATED ANALYSIS OF RNA-SEQUENCING (RNA-SEQ) AND CHROMATIN IMMUNOPRECIPITATION SEQUENCING (CHIP-SEQ) FURTHER REVEALED THAT H19 REGULATED THE REPROGRAMMING OF EZH2-MEDIATED H3K27ME3 PROFILES, WHICH EPIGENETICALLY PROMOTED SEVERAL PATHWAYS FAVORING HSCS ACTIVATION AND PROLIFERATION, INCLUDING EPITHELIAL-MESENCHYMAL TRANSITION AND WNT/BETA-CATENIN SIGNALING. IN CONCLUSION, HIGHLY EXPRESSED H19 IN CHRONIC LIVER DISEASES PROMOTES FIBROGENESIS BY REPROGRAMMING EZH2-MEDIATED EPIGENETIC REGULATION OF HSCS ACTIVATION. TARGETING THE H19-EZH2 INTERACTION MAY SERVE AS A NOVEL THERAPEUTIC APPROACH FOR LIVER FIBROSIS. 2023 3 4159 37 MECP2 CONTROLS AN EPIGENETIC PATHWAY THAT PROMOTES MYOFIBROBLAST TRANSDIFFERENTIATION AND FIBROSIS. BACKGROUND & AIMS: MYOFIBROBLAST TRANSDIFFERENTIATION GENERATES HEPATIC MYOFIBROBLASTS, WHICH PROMOTE LIVER FIBROGENESIS. THE PEROXISOME PROLIFERATOR-ACTIVATED RECEPTOR GAMMA (PPARGAMMA) IS A NEGATIVE REGULATOR OF THIS PROCESS. WE INVESTIGATED EPIGENETIC REGULATION OF PPARGAMMA AND MYOFIBROBLAST TRANSDIFFERENTIATION. METHODS: CHROMATIN IMMUNOPRECIPITATION (CHIP) ASSAYS ASSESSED THE BINDING OF METHYL-CPG BINDING PROTEIN 2 (MECP2) TO PPARGAMMA AND CHROMATIN MODIFICATIONS THAT SILENCE THIS GENE. MECP2(-/Y) MICE AND AN INHIBITOR (DZNEP) OF THE EPIGENETIC REGULATORY PROTEIN EZH2 WERE USED IN THE CARBON TETRACHLORIDE MODEL OF LIVER FIBROSIS. LIVER TISSUES FROM MICE WERE ASSESSED BY HISTOLOGIC ANALYSIS; MARKERS OF FIBROSIS WERE MEASURED BY QUANTITATIVE POLYMERASE CHAIN REACTION (QPCR). REVERSE TRANSCRIPTION PCR DETECTED CHANGES IN EXPRESSION OF THE MICRORNA MIR132 AND ITS TARGET, ELONGATED TRANSCRIPTS OF MECP2. MYOFIBROBLASTS WERE TRANSFECTED WITH MIR132; PPARGAMMA AND MECP2 EXPRESSIONS WERE ANALYZED BY QPCR OR IMMUNOBLOTTING. RESULTS: MYOFIBROBLAST TRANSDIFFERENTIATION OF HEPATIC STELLATE CELLS IS CONTROLLED BY A COMBINATION OF MECP2, EZH2, AND MIR132 IN A RELAY PATHWAY. THE PATHWAY IS ACTIVATED BY DOWN-REGULATION OF MIR132, RELEASING THE TRANSLATIONAL BLOCK ON MECP2. MECP2 IS RECRUITED TO THE 5' END OF PPARGAMMA, WHERE IT PROMOTES METHYLATION BY H3K9 AND RECRUITS THE TRANSCRIPTION REPRESSOR HP1ALPHA. MECP2 ALSO STIMULATES EXPRESSION OF EZH2 AND METHYLATION OF H3K27 TO FORM A REPRESSIVE CHROMATIN STRUCTURE IN THE 3' EXONS OF PPARGAMMA. GENETIC AND PHARMACOLOGIC DISRUPTIONS OF MECP2 OR EZH2 REDUCED THE FIBROGENIC CHARACTERISTICS OF MYOFIBROBLASTS AND ATTENUATED FIBROGENESIS. CONCLUSIONS: LIVER FIBROSIS IS REGULATED BY AN EPIGENETIC RELAY PATHWAY THAT INCLUDES MECP2, EZH2, AND MIR132. REAGENTS THAT INTERFERE WITH THIS PATHWAY MIGHT BE DEVELOPED TO REDUCE FIBROGENESIS IN CHRONIC LIVER DISEASE. 2010 4 2349 48 EPIGENETIC REGULATION OF MYOFIBROBLAST DIFFERENTIATION AND EXTRACELLULAR MATRIX PRODUCTION IN NASAL POLYP-DERIVED FIBROBLASTS. BACKGROUND: NASAL POLYPOSIS IS A MULTI-FACTORIAL DISEASE ASSOCIATED WITH CHRONIC INFLAMMATORY CONDITION OF THE PARANASAL SINUSES. MYOFIBROBLAST DIFFERENTIATION AND EXTRACELLULAR MATRIX (ECM) ACCUMULATION ARE INVOLVED IN THE PATHOGENESIS OF NASAL POLYPOSIS. OBJECTIVE: THE AIM OF THIS STUDY WAS TO STUDY THE EFFECT OF TRICHOSTATIN A (TSA), A HISTONE DEACETYLASE (HDAC) INHIBITOR, ON TRANSFORMING GROWTH FACTOR (TGF)-BETA1-INDUCED MYOFIBROBLAST DIFFERENTIATION AND ECM ACCUMULATION IN NASAL POLYP-DERIVED FIBROBLASTS (NPDFS). METHODS: NASAL POLYP-DERIVED FIBROBLASTS WERE ISOLATED FROM NASAL POLYPS OF PATIENTS WHO HAVE CHRONIC RHINOSINUSITIS WITH NASAL POLYP. TSA WAS TREATED IN TGF-BETA1-INDUCED NPDFS. EXPRESSION LEVELS OF HDAC2, ALPHA-SMOOTH MUSCLE ACTIN (SMA), TGF-BETA1, COLLAGEN TYPE I, ACETYLATED HISTONE H3, ACETYLATED HISTONE H4, PHOSPHORYLATED SMAD2/3 AND SMAD7 WERE DETERMINED BY RT-PCR, WESTERN BLOT AND/OR IMMUNOFLUORESCENT STAINING. THE TOTAL COLLAGEN AMOUNT PRODUCTION WAS ANALYSED BY SIRCOL SOLUBLE COLLAGEN ASSAY AND CONTRACTILE ACTIVITY WAS MEASURED BY COLLAGEN GEL CONTRACTION ASSAY. HDAC2 INHIBITION BY TSA OR HDAC2 SILENCING WAS ESTABLISHED BY RT-PCR AND WESTERN BLOT. THE EPIGENETIC EFFECT ON ALPHA-SMA GENE INACTIVATION WAS EXAMINED BY CHROMATIN IMMUNOPRECIPITATION ASSAY. PROLIFERATION WAS DETERMINED BY KI67-POSITIVE CELL STAINING AND CYTOTOXICITY WAS ASSESSED BY 3-(4,5- DIMETHYLTHIAZOL-2YL)-2,5-DIPHENYL-2H-TETRAZOLIUM BROMIDE (MTT) ASSAY. RESULTS: THE EXPRESSION LEVELS OF HDAC2, ALPHA-SMA AND TGF-BETA1 WERE INCREASED IN NASAL POLYP TISSUES COMPARED TO NORMAL INFERIOR TURBINATE TISSUES. TSA AND HDAC2 SILENCING INHIBITED EXPRESSION LEVELS ALPHA-SMA, COLLAGEN AND HDAC2. TSA INDUCED HYPERACETYLATION OF HISTONE AND SUPPRESSED OPENING OF ALPHA-SMA GENE PROMOTER IN TGF-BETA1-INDUCED NPDFS. TSA INHIBITED TGF-BETA1-INDUCED SMAD 2/3 AND RESCUED TGF-BETA1-SUPPRESSED SMAD7 SIGNALLING PATHWAY. FINALLY, TSA BLOCKED PROLIFERATION IN TGF-BETA1-INDUCED NPDFS AND HAS NO CYTOTOXIC EFFECT IN NPDFS. CONCLUSIONS AND CLINICAL RELEVANCE: THESE RESULTS SUGGEST THAT HDAC INHIBITION IS ASSOCIATED WITH MYOFIBROBLAST DIFFERENTIATION AND EXTRACELLUAR MATRIX ACCUMULATION IN NASAL POLYPOSIS. TSA MAY BE USEFUL AS AN INHIBITOR OF NASAL POLYP GROWTH, AND THUS HAS POTENTIAL TO BE USED AS A NOVEL TREATMENT OPTION FOR NASAL POLYPOSIS. 2012 5 1826 49 EFFECTS OF HISTONE DEACETYLASE INHIBITOR ON EXTRACELLULAR MATRIX PRODUCTION IN HUMAN NASAL POLYP ORGAN CULTURES. BACKGROUND: NASAL POLYPOSIS IS ASSOCIATED WITH A CHRONIC INFLAMMATORY CONDITION OF THE SINONASAL MUCOSA AND INVOLVES MYOFIBROBLAST DIFFERENTIATION AND EXTRACELLULAR MATRIX (ECM) ACCUMULATION. EPIGENETIC MODULATION BY HISTONE DEACETYLASE (HDAC) INHIBITORS INCLUDING TRICHOSTATIN A (TSA) HAS BEEN REPORTED TO HAVE INHIBITORY EFFECTS ON MYOFIBROBLAST DIFFERENTIATION IN LUNG AND RENAL FIBROBLASTS. THE PURPOSE OF THIS STUDY WAS TO INVESTIGATE THE INHIBITORY EFFECT OF TSA ON MYOFIBROBLAST DIFFERENTIATION AND ECM PRODUCTION IN NASAL POLYP ORGAN CULTURES. METHODS: NASAL POLYP TISSUES FROM 18 PATIENTS WERE ACQUIRED DURING ENDOSCOPIC SINUS SURGERY. AFTER ORGAN CULTURE, NASAL POLYPS WERE STIMULATED WITH TGF-BETA1 AND THEN TREATED WITH TSA. ALPHA-SMOOTH MUSCLE ACTIN (ALPHA-SMA), FIBRONECTIN, AND COLLAGEN TYPE I EXPRESSION LEVELS WERE EXAMINED BY REVERSE TRANSCRIPTION-POLYMERASE CHAIN REACTION (PCR), REAL-TIME PCR, WESTERN BLOT, AND IMMUNOFLUORESCENT STAINING. HDAC2, HDAC4, AND ACETYLATED H4 EXPRESSION LEVELS WERE ASSAYED BY WESTERN BLOT. CYTOTOXICITY WAS ANALYZED BY THE TERMINAL DEOXYNUCLEOTIDYL TRANSFERASE BIOTIN-DUTP NICK END LABELING ASSAY. RESULTS: THE EXPRESSION LEVELS OF ALPHA-SMA, FIBRONECTIN, AND COLLAGEN TYPE 1 WERE INCREASED IN NASAL POLYP AFTER TRANSFORMING GROWTH FACTOR (TGF) BETA1 TREATMENT. TSA-INHIBITED TGF-BETA1 INDUCED THESE GENE AND PROTEIN EXPRESSION LEVELS. FURTHERMORE, TSA SUPPRESSED PROTEIN EXPRESSION LEVELS OF HDAC2 AND HDAC4. HOWEVER, TSA INDUCED HYPERACETYLATION OF HISTONES H4. TREATMENT WITH TGF-BETA1 WITH OR WITHOUT TSA DID NOT HAVE CYTOTOXIC EFFECT. CONCLUSION: THESE FINDINGS PROVIDE NOVEL INSIGHTS INTO THE EPIGENETIC REGULATION IN MYOFIBROBLAST DIFFERENTIATION AND ECM PRODUCTION OF NASAL POLYP. TSA COULD BE A CANDIDATE OF A THERAPEUTIC AGENT FOR REVERSING THE TGF-BETA1-INDUCED ECM SYNTHESIS THAT LEADS TO NASAL POLYP DEVELOPMENT. 2013 6 3792 31 INTERLEUKIN-1BETA INCREASES THE RISK OF GASTRIC CANCER THROUGH INDUCTION OF ABERRANT DNA METHYLATION IN A MOUSE MODEL. INTERLEUKIN-1BETA (IL-1BETA) HAS A SIGNIFICANT ROLE IN CHRONIC GASTRIC INFLAMMATION AND MANIFESTATIONS OF GASTRIC DISEASES. THE PRESENT STUDY AIMED TO ELUCIDATE THE SPECIFIC ROLE OF IL-1BETA IN INDUCTION OF DNA METHYLATION USING IL-1 RECEPTOR TYPE 1 KNOCKOUT (IL-1R1(-)/(-)) MICE. IN THE PRESENT STUDY, WILD-TYPE (WT) AND IL-1R1(-)/(-) MICE WERE INJECTED WITH IL-1BETA (5 MICROG/KG/DAY). SERUM LEVELS OF IL-1BETA, INTERLEUKIN-6 (IL-6) AND NITRIC OXIDE (NO) WERE MEASURED BY ENZYME-LINKED IMMUNOSORBENT OR NO ASSAYS. E-CADHERIN (E-CAD) METHYLATION STATUS AND MESSENGER (M)RNA EXPRESSION OF IL-1BETA, IL-6, E-CAD AND INDUCIBLE NITRIC OXIDE SYNTHASE (INOS) WERE ANALYZED. RESULTS FROM THE PRESENT STUDY INDICATED SIGNIFICANTLY HIGHER IL-1BETA MRNA EXPRESSION (P<0.001) IN WT MICE COMPARED WITH IL-1R1(-)/(-) MICE. IL-1BETA AND IL-6 RELEASE WAS SIGNIFICANTLY INCREASED IN TREATED WT MICE COMPARED WITH IL-1R1(-)/(-) MICE AT 1 H, 4 H AND 8 H (ALL P<0.005). IL-1BETA RELEASE WAS ONLY DETECTED IN WT MICE FOLLOWING A SECOND DOSE MEASURED AT DAY 3, WEEK 1 AND WEEK 2 WHEN COMPARED WITH IL-1R1(-)/(-) MICE. PROMOTER METHYLATION OF E-CAD AND A DECREASE IN GENE EXPRESSION WAS OBSERVED IN TREATED WT MICE. MRNA EXPRESSION OF INOS IN WT MICE WAS SIGNIFICANTLY INCREASED AT WEEK 1 COMPARED WITH IL-1R1(-)/(-) MICE (P=0.0411). FURTHERMORE, A SIGNIFICANTLY INCREASED LEVEL OF NO PRODUCTION WAS OBSERVED IN TREATED WT MICE (P<0.005 AT 8 H AND WEEK 1; P<0.001 AT 4 H AND DAY 3) WHEN COMPARED WITH IL-1R1(-)/(-) MICE. THE PRESENT RESULTS INDICATED THAT IL-1BETA WAS ABLE TO DIRECTLY INDUCE DNA METHYLATION, WHICH MAY LINK INFLAMMATION-INDUCED EPIGENETIC CHANGES AND THE DEVELOPMENT OF GASTRIC DISEASES. 2016 7 1632 42 DNMTS ARE INVOLVED IN TGF-BETA1-INDUCED EPITHELIAL-MESENCHYMAL TRANSITIONS IN AIRWAY EPITHELIAL CELLS. CHRONIC RHINOSINUSITIS (CRS) PATHOGENESIS IS CLOSELY RELATED TO TISSUE REMODELING, INCLUDING EPITHELIAL-MESENCHYMAL TRANSITION (EMT). EPIGENETIC MECHANISMS PLAY KEY ROLES IN EMT. DNA METHYLATION, MEDIATED BY DNA METHYLTRANSFERASES (DNMTS), IS AN EPIGENETIC MARKER THAT IS CRITICAL TO EMT. THE GOAL OF THIS STUDY WAS TO DETERMINE WHETHER DNMTS WERE INVOLVED IN TGF-BETA1-INDUCED EMT AND ELUCIDATE THE UNDERLYING MECHANISMS IN NASAL EPITHELIAL CELLS AND AIR-LIQUID INTERFACE CULTURES. GLOBAL DNA METHYLATION AND DNMT ACTIVITY WERE QUANTIFIED. DNMT EXPRESSION WAS MEASURED USING REAL-TIME PCR (QRT-PCR) IN HUMAN CRS TISSUES. MRNA AND PROTEIN LEVELS OF DNMTS, E-CADHERIN, VIMENTIN, ALPHA-SMA, AND FIBRONECTIN WERE DETERMINED USING RT-PCR AND WESTERN BLOTTING, RESPECTIVELY. DNMT1, DNMT3A, AND DNMT3B GENE EXPRESSION WERE KNOCKED DOWN USING SIRNA TRANSFECTION. MAPK PHOSPHORYLATION AND EMT-RELATED TRANSCRIPTION FACTOR LEVELS WERE DETERMINED USING WESTERN BLOTTING. SIGNALING PATHWAYS WERE ANALYZED USING SPECIFIC INHIBITORS OF MAPK. WE DEMONSTRATED THESE DATA IN PRIMARY NASAL EPITHELIAL CELLS AND AIR-LIQUID INTERFACE CULTURES. GLOBAL DNA METHYLATION, DNMT ACTIVITY, AND DNMT EXPRESSION INCREASED IN CRS TISSUES. DNMT EXPRESSION WAS POSITIVELY CORRELATED WITH LUND-MCKAY CT SCORES. TGF-BETA1 DOSE-DEPENDENTLY INDUCED DNMT EXPRESSION. FURTHER, 5-AZA INHIBITED TGF-BETA1-INDUCED DNMT, SNAIL, AND SLUG EXPRESSION RELATED TO EMT, AS WELL AS P38 AND JNK PHOSPHORYLATION IN A549 CELLS AND TGF-BETA1-INDUCED DNMT EXPRESSION AND EMT IN PRIMARY NASAL EPITHELIAL CELLS AND AIR-LIQUID INTERFACE CULTURES. TGF-BETA1-INDUCED DNMT EXPRESSION LEADS TO DNA METHYLATION AND EMT VIA P38, JNK, SNAIL, AND SLUG SIGNALING PATHWAYS. INHIBITION OF DNMT SUPPRESSED THE EMT PROCESS AND THEREFORE IS POTENTIALLY A CRS THERAPEUTIC STRATEGY. 2022 8 4877 52 OVEREXPRESSION OF MIR-4433 BY SUBEROYLANILIDE HYDROXAMIC ACID SUPPRESSES GROWTH OF CML CELLS AND INDUCES APOPTOSIS THROUGH TARGETING BCR-ABL. BACKGROUND: TARGETING BCR-ABL IS THE KEY FOR THE TREATMENT OF CML. ALTHOUGH GREAT PROGRESS HAS BEEN ACHIEVED FOR THE TREATMENT OF CML PATIENTS IN CHRONIC STAGE, EFFECTIVE DRUGS WITH GOOD SAFETY ARE NOT AVAILABLE FOR THOSE IN ADVANCED STAGES OF CML PATIENTS. IN PRESENT STUDY, A HISTONE DEACETYLASE INHIBITOR, SUBEROYLANILIDE HYDROXAMIC ACID (SAHA), WAS USED TO SCREEN FOR MICRORNA THAT CAN TARGET BCR-ABL. METHODS: RT-QPCR WAS USED TO DETERMINE BCR-ABL AND MIR-4433 TRANSCRIPTION LEVEL IN CML CELLS. IN CML CELLS, PROTEINS INCLUDING PARP, CASPASE-3, ACETYL-HISTONE 3, HISTONE 3 AND BCR-ABL, AS WELL AS BCR-ABL DOWNSTREAM PROTEINS WERE DETECTED USING WESTERN BLOT. CELL VIABILITY AND APOPTOSIS WERE MONITORED RESPECTIVELY BY MTS ASSAY AND FLOW CYTOMETRY. THE CORRELATION BETWEEN MIR-4433 AND BCR-ABL WAS DETERMINED BY LUCIFERASE REPORTER ASSAY. THE ANTI-TUMOR EFFECT OF MIR-4433 TO K562 CELLS WAS EVALUATED BY NUDE MOUSE XENOGRAFT MODEL IN VIVO. RESULTS: SAHA UP-REGULATED THE ACETYLATION LEVEL OF HISTONE 3, AND EFFECTIVELY INHIBITED BCR-ABL MRNA LEVEL AND ITS DOWNSTREAM SIGNAL TRANSDUCTION PATHWAY, WHILE INHIBITING THE GROWTH OF CML CELLS AND INDUCING APOPTOSIS. FURTHERMORE, BIOINFORMATICS TOOLS PREDICTED THAT MIR-4433 IS A PUTATIVE MICRORNA TARGETING BCR-ABL AND THAT THE EXPRESSION LEVEL OF MIR-4433 WAS SIGNIFICANTLY INCREASED AFTER SAHA TREATMENT IN K562 CELLS. LUCIFERASE ACTIVITY ANALYSIS REVEALED THAT MIR-4433 DIRECTLY TARGETS BCR-ABL. ADDITIONALLY, TRANSIENT EXPRESSION OF MIR-4433 ABROGATED BCR-ABL ACTIVITY AND ITS DOWNSTREAM SIGNALING PATHWAYS WHILE INDUCING APOPTOSIS IN K562 CELLS. MOREOVER, STABLE EXPRESSION OF MIR-4433 SUPPRESSED BCR-ABL AND ITS DOWNSTREAM SIGNALING PATHWAY, AND INHIBITED THE GROWTH OF K562 CELLS IN VITRO AND THE GROWTH OF K562-XENOGRAFTS IN NUDE MICE. CONCLUSION: MIR-4433 WAS IDENTIFIED AS A MICRORNA TARGETING BCR-ABL, WHICH MAY BE SUBJECT TO EPIGENETIC REGULATION OF SAHA, A HISTONE DEACETYLASE INHIBITOR THAT HAS BEEN APPROVED BY THE US FDA FOR THE TREATMENT OF CUTANEOUS T-CELL LYMPHOMA. THE FINDINGS OF THIS STUDY PROVIDE A MOLECULAR BASIS FROM ANOTHER ANGLE FOR THE USE OF SAHA IN THE TREATMENT OF CML. 2019 9 6020 43 THE ATTENUATION OF RENAL FIBROSIS BY HISTONE DEACETYLASE INHIBITORS IS ASSOCIATED WITH THE PLASTICITY OF FOXP3(+)IL-17(+) T CELLS. BACKGROUND: THE HISTONE DEACETYLASE (HDAC) INHIBITOR, WHICH HAS POTENTIAL EFFECTS ON EPIGENETIC MODIFICATIONS, HAD BEEN REPORTED TO ATTENUATE RENAL FIBROSIS. CD4(+) FORKHEAD BOX P3 (FOXP3)(+) T REGULATORY (TREG) CELLS MAY BE CONVERTED TO INFLAMMATION-ASSOCIATED T HELPER 17 CELLS (TH17) WITH TISSUE FIBROSIS PROPERTIES. THE ASSOCIATION BETWEEN FOXP3(+)IL-17(+) T CELLS AND THE ATTENUATION OF RENAL FIBROSIS BY THE HDAC INHIBITOR IS NOT CLEAR. METHODS: THIS STUDY EVALUATED THE ROLES OF THE HDAC INHIBITOR, TREG CELLS AND THEIR DIFFERENTIATION INTO TH17 CELLS, WHICH AGGRAVATE CHRONIC INFLAMMATION AND RENAL FIBROSIS IN A UNILATERAL URETERAL OBSTRUCTION (UUO) MOUSE MODEL. THE STUDY GROUPS INCLUDED CONTROL AND UUO MICE THAT WERE MONITORED FOR 7, 14 OR 21 DAYS. RESULTS: JUXTAGLOMERULAR (JG) HYPERPLASIA, ANGIOTENSIN II TYPE 1 RECEPTOR (AT1R) EXPRESSION AND LYMPHOCYTE INFILTRATION WERE OBSERVED IN RENAL TISSUES AFTER UUO BUT WERE DECREASED AFTER TRICHOSTATIN A (TSA) TREATMENT, A HDAC INHIBITOR. THE NUMBER OF CD4(+)FOXP3(+) T CELLS INCREASED PROGRESSIVELY, ALONG WITH THE NUMBER OF FOXP3(+)INTERLEUKIN (IL)-17(+) T CELLS, AFTER 14 DAYS, AND THEIR NUMBERS THEN PROGRESSIVELY DECREASED WITH INCREASING CD4(+)IL-17(+) T CELL NUMBERS, AS DEMONSTRATED BY DOUBLE IMMUNOHISTOCHEMISTRY. PROGRESSIVE RENAL FIBROSIS WAS ASSOCIATED WITH THE LOSS OF CD4(+)FOXP3(+)IL-17(+) T CELLS IN SPLENIC SINGLE-CELL SUSPENSIONS. FOXP3(+)IL-17(+) T CELLS EXPRESSED TGF-BETA1 BOTH IN VITRO AND IN VIVO, AND TGF-BETA1 EXPRESSION WAS SIGNIFICANTLY KNOCKDOWN BY IL-17 SIRNA IN VITRO. THESE CELLS WERE FOUND TO PLAY A ROLE IN CONVERTING TREGS INTO IL-17- AND TGF-BETA1-PRODUCING CELLS. CONCLUSIONS: TSA TREATMENT DECREASED JG HYPERPLASIA, THE PERCENTAGE OF FOXP3(+)IL-17(+) CELLS AND THE DEGREE OF FIBROSIS, SUGGESTING THAT THERAPEUTIC BENEFITS MAY RESULT FROM EPIGENETIC MODIFICATIONS. 2017 10 692 34 BRD4 PROMOTES HEPATIC STELLATE CELLS ACTIVATION AND HEPATIC FIBROSIS VIA MEDIATING P300/H3K27AC/PLK1 AXIS. HEPATIC FIBROSIS (HF) IS A REVERSIBLE WOUND-HEALING RESPONSE CHARACTERIZED BY EXCESSIVE EXTRACELLULAR MATRIX (ECM) DEPOSITION AND SECONDARY TO PERSISTENT CHRONIC INJURY. BROMODOMAIN PROTEIN 4 (BRD4) COMMONLY FUNCTIONS AS A "READER" TO REGULATE EPIGENETIC MODIFICATIONS INVOLVED IN VARIOUS BIOLOGICAL AND PATHOLOGICAL EVENTS, BUT THE MECHANISM OF HF REMAINS UNCLEAR. IN THIS STUDY, WE ESTABLISHED A CCL(4)-INDUCED HF MODEL AND SPONTANEOUS RECOVERY MODEL IN MICE AND FOUND ABERRANT BRD4 EXPRESSION, WHICH WAS CONSISTENT WITH THE RESULTS IN HUMAN HEPATIC STELLATE CELLS (HSCS)- LX2 CELLS IN VITRO. SUBSEQUENTLY, WE FOUND THAT DISTRICTION AND INHIBITION OF BRD4 RESTRAINED TGFBETA-INDUCED TRANS-DIFFERENTIATION OF LX2 CELLS INTO ACTIVATED, PROLIFERATIVE MYOFIBROBLASTS AND ACCELERATED APOPTOSIS, AND BRD4 OVEREXPRESSION BLOCKED MDI-INDUCED LX2 CELLS INACTIVATION AND PROMOTED THE PROLIFERATION AND INHIBITED APOPTOSIS OF INACTIVATED CELLS. ADDITIONALLY, ADENO-ASSOCIATED VIRUS SEROTYPE 8-LOADED SHORT HAIRPIN RNA-MEDIATED BRD4 KNOCKDOWN IN MICE SIGNIFICANTLY ATTENUATED CCL(4)-INDUCED FIBROTIC RESPONSES INCLUDING HSCS ACTIVATION AND COLLAGEN DEPOSITION. MECHANISTICALLY, BRD4 DEFICIENCY INHIBITED PLK1 EXPRESSION IN ACTIVATED LX2 CELLS, AND CHIP AND CO-IP ASSAYS REVEALED THAT BRD4 REGULATION OF PLK1 WAS DEPENDENT ON P300-MEDIATED ACETYLATION MODIFICATION FOR H3K27 ON THE PLK1 PROMOTER. IN CONCLUSION, BRD4 DEFICIENCY IN THE LIVER ALLEVIATES CCL(4)-INDUCED HF IN MICE, AND BRD4 PARTICIPATES IN THE ACTIVATION AND REVERSAL OF HSCS THROUGH POSITIVELY REGULATING THE P300/H3K27AC/PLK1 AXIS, PROVIDING A POTENTIAL INSIGHT FOR HF THERAPY. 2023 11 3720 39 INHIBITION OF CLASS I HISTONE DEACETYLASES ABROGATES TUMOR GROWTH FACTOR BETA EXPRESSION AND DEVELOPMENT OF FIBROSIS DURING CHRONIC PANCREATITIS. PANCREATIC FIBROSIS IS THE HALLMARK OF CHRONIC PANCREATITIS, A HIGHLY DEBILITATING DISEASE FOR WHICH THERE IS CURRENTLY NO CURE. THE KEY EVENT AT THE BASIS OF PANCREATIC FIBROSIS IS THE DEPOSITION OF EXTRACELLULAR MATRIX PROTEINS BY ACTIVATED PANCREATIC STELLATE CELLS (PSCS). TRANSFORMING GROWTH FACTOR BETA (TGFBETA) IS A POTENT PROFIBROTIC FACTOR IN THE PANCREAS AS IT PROMOTES THE ACTIVATION OF PSC; THUS, PHARMACOLOGIC INTERVENTIONS THAT EFFECTIVELY REDUCE TGFBETA EXPRESSION HARBOR CONSIDERABLE THERAPEUTIC POTENTIAL IN THE TREATMENT OF CHRONIC PANCREATITIS. IN THIS STUDY, WE INVESTIGATED WHETHER TGFBETA EXPRESSION IS REDUCED BY PHARMACOLOGIC INHIBITION OF THE EPIGENETIC MODIFIERS HISTONE DEACETYLASES (HDACS). TO ADDRESS THIS AIM, CHRONIC PANCREATITIS WAS INDUCED IN C57BL/6 MICE WITH SERIAL INJECTIONS OF CERULEIN, AND THE SELECTIVE CLASS 1 HDAC INHIBITOR MS-275 WAS ADMINISTERED IN VIVO IN A PREVENTIVE AND THERAPEUTIC MANNER. BOTH MS-275 REGIMENS POTENTLY REDUCED DEPOSITION OF EXTRACELLULAR MATRIX AND DEVELOPMENT OF FIBROSIS IN THE PANCREAS AFTER 4 WEEKS OF CHRONIC PANCREATITIS. REDUCED PANCREATIC FIBROSIS WAS CONCOMITANT WITH LOWER EXPRESSION OF PANCREATIC TGFBETA AND CONSEQUENT REDUCED PSC ACTIVATION. IN SEARCH OF THE CELL TYPES TARGETED BY THE INHIBITOR, WE FOUND THAT MS-275 TREATMENT ABROGATED THE EXPRESSION OF TGFBETA IN ACINAR CELLS STIMULATED BY CERULEIN TREATMENT. OUR STUDY DEMONSTRATES THAT MS-275 IS AN EFFECTIVE ANTIFIBROTIC AGENT IN THE CONTEXT OF EXPERIMENTAL CHRONIC PANCREATITIS AND THUS MAY CONSTITUTE A VALID THERAPEUTIC INTERVENTION FOR THIS SEVERE DISEASE. 2018 12 878 52 CHRONIC CADMIUM EXPOSURE AGGRAVATES MALIGNANT PHENOTYPES OF NASOPHARYNGEAL CARCINOMA BY ACTIVATING THE WNT/BETA-CATENIN SIGNALING PATHWAY VIA HYPERMETHYLATION OF THE CASEIN KINASE 1ALPHA PROMOTER. BACKGROUND: OUR PREVIOUS STUDY HAS SHOWN THAT CADMIUM (CD) EXPOSURE IS NOT ONLY A RISK FACTOR FOR NASOPHARYNGEAL CARCINOMA (NPC), BUT ALSO CORRELATED WITH THE CLINICAL STAGE AND LYMPH NODE METASTASIS. HOWEVER, THE UNDERLYING MOLECULAR EVENTS OF CD INVOLVED IN NPC PROGRESSION REMAIN TO BE ELUCIDATED. PURPOSE: THE OBJECTIVE OF THIS STUDY WAS TO DECIPHER HOW CD IMPACTS THE MALIGNANT PHENOTYPES OF NPC CELLS. METHODS: NPC CELL LINES CNE-1 AND CNE-2 WERE CONTINUOUSLY EXPOSED WITH 1 MUM CD CHLORIDE FOR 10 WEEKS, DESIGNATING AS CHRONIC CD TREATED NPC CELLS (CCT-NPC). MTT ASSAY, COLONY FORMATION ASSAY AND XENOGRAFT TUMOR GROWTH WERE USED TO ASSESS CELL VIABILITY IN VITRO AND IN VIVO. TRANSWELL ASSAYS WERE PERFORMED TO DETECT CELL INVASION AND MIGRATION. THE PROTEIN LEVELS OF E-CADHERIN, N-CADHERIN, VIMENTIN AS WELL AS BETA-CATENIN AND CASEIN KINASE 1ALPHA(CK1ALPHA) WERE MEASURED BY WESTERN BLOT. IMMUNOFLUORESCENCE STAINING WAS USED TO OBSERVE THE DISTRIBUTION OF FILAMENT ACTIN (F-ACTIN), BETA-CATENIN AND CK1ALPHA. THE MRNA LEVELS OF DOWNSTREAM TARGET GENES OF BETA-CATENIN WERE DETECTED BY RT-PCR. WNT/BETA-CATENIN SIGNALING ACTIVITY WAS ASSESSED BY TOPFLASH/FOPFLASH DUAL LUCIFERASE REPORT SYSTEM. MS-PCR WAS USED TO DETECT THE METHYLATION STATUS OF CK1ALPHA. FINALLY, THE ACTIVATION OF WNT/BETA-CATENIN PATHWAY AND CELL BIOLOGICAL PROPERTIES WERE EXAMINED FOLLOWING TREATMENT OF CCT-NPC CELLS WITH 5-AZA-2-DEOXY-CYTIDINE(5-AZA-CDR). RESULTS: CCT-NPC CELLS SHOWED AN INCREASE IN CELL PROLIFERATION, COLONY FORMATION, INVASION AND MIGRATION COMPARED TO THE PARENTAL CELLS. CD ALSO INDUCED CYTOSKELETON REORGANIZATION AND EPITHELIAL-TO-MESENCHYMAL TRANSITION. UPREGULATION AND NUCLEAR TRANSLOCATION OF BETA-CATENIN AND INCREASED LUCIFERASE ACTIVITY ACCOMPANIED WITH TRANSCRIPTION OF DOWNSTREAM TARGET GENES WERE FOUND IN CCT-NPC CELLS. TREATMENT OF CCT-CNE1 CELLS WITH 5-AZA-CDR COULD REVERSE THE HYPERMETHYLATION OF CK1ALPHA AND ATTENUATE THE CELL MALIGNANCY. CONCLUSION: THESE RESULTS SUPPORT A ROLE FOR CHRONIC CD EXPOSURE AS A DRIVING FORCE FOR THE MALIGNANT PROGRESSION OF NPC VIA EPIGENETIC ACTIVATION OF THE WNT/BETA-CATENIN PATHWAY. 2019 13 2590 37 EPIGENETICS OF PROTEASOME INHIBITION IN THE LIVER OF RATS FED ETHANOL CHRONICALLY. AIM: TO EXAMINE THE EFFECTS OF ETHANOL-INDUCED PROTEASOME INHIBITION, AND THE EFFECTS OF PROTEASOME INHIBITION IN THE REGULATION OF EPIGENETIC MECHANISMS. METHODS: RATS WERE FED ETHANOL FOR 1 MO USING THE TSUKAMOTO-FRENCH MODEL AND WERE COMPARED TO RATS GIVEN THE PROTEASOME INHIBITOR PS-341 (BORTEZOMIB, VELCADE(TM)) BY INTRAPERITONEAL INJECTION. MICROARRAY ANALYSIS AND REAL TIME PCR WERE PERFORMED AND PROTEASOME ACTIVITY ASSAYS AND WESTERN BLOT ANALYSIS WERE PERFORMED USING ISOLATED NUCLEI. RESULTS: CHRONIC ETHANOL FEEDING CAUSED A SIGNIFICANT INHIBITION OF THE UBIQUITIN PROTEASOME PATHWAY IN THE NUCLEUS, WHICH LED TO CHANGES IN THE TURNOVER OF TRANSCRIPTIONAL FACTORS, HISTONE-MODIFYING ENZYMES, AND, THEREFORE, AFFECTED EPIGENETIC MECHANISMS. CHRONIC ETHANOL FEEDING WAS RELATED TO AN INCREASE IN HISTONE ACETYLATION, AND IT IS HYPOTHESIZED THAT THE PROTEASOME PROTEOLYTIC ACTIVITY REGULATED HISTONE MODIFICATIONS BY CONTROLLING THE STABILITY OF HISTONE MODIFYING ENZYMES, AND, THEREFORE, REGULATED THE CHROMATIN STRUCTURE, ALLOWING EASY ACCESS TO CHROMATIN BY RNA POLYMERASE, AND, THUS, PROPER GENE EXPRESSION. PROTEASOME INHIBITION BY PS-341 INCREASED HISTONE ACETYLATION SIMILAR TO CHRONIC ETHANOL FEEDING. IN ADDITION, PROTEASOME INHIBITION CAUSED DRAMATIC CHANGES IN HEPATIC REMETHYLATION REACTIONS AS THERE WAS A SIGNIFICANT DECREASE IN THE ENZYMES RESPONSIBLE FOR THE REGENERATION OF S-ADENOSYLMETHIONINE, AND, IN PARTICULAR, A SIGNIFICANT DECREASE IN THE BETAINE-HOMOCYSTEINE METHYLTRANSFERASE ENZYME. THIS SUGGESTED THAT HYPOMETHYLATION WAS ASSOCIATED WITH PROTEASOME INHIBITION, AS INDICATED BY THE DECREASE IN HISTONE METHYLATION. CONCLUSION: THE ROLE OF PROTEASOME INHIBITION IN REGULATING EPIGENETIC MECHANISMS, AND ITS LINK TO LIVER INJURY IN ALCOHOLIC LIVER DISEASE, IS THUS A PROMISING APPROACH TO STUDY LIVER INJURY DUE TO CHRONIC ETHANOL CONSUMPTION. 2009 14 922 33 CHRONIC IL-1BETA-INDUCED INFLAMMATION REGULATES EPITHELIAL-TO-MESENCHYMAL TRANSITION MEMORY PHENOTYPES VIA EPIGENETIC MODIFICATIONS IN NON-SMALL CELL LUNG CANCER. CHRONIC INFLAMMATION FACILITATES TUMOR PROGRESSION. WE DISCOVERED THAT A SUBSET OF NON-SMALL CELL LUNG CANCER CELLS UNDERWENT A GRADUALLY PROGRESSING EPITHELIAL-TO-MESENCHYMAL (EMT) PHENOTYPE FOLLOWING A 21-DAY EXPOSURE TO IL-1BETA, AN ABUNDANT PROINFLAMMATORY CYTOKINE IN THE AT-RISK FOR LUNG CANCER PULMONARY AND THE LUNG TUMOR MICROENVIRONMENTS. PATHWAY ANALYSIS OF THE GENE EXPRESSION PROFILE AND IN VITRO FUNCTIONAL STUDIES REVEALED THAT THE EMT AND EMT-ASSOCIATED PHENOTYPES, INCLUDING ENHANCED CELL INVASION, PD-L1 UPREGULATION, AND CHEMORESISTANCE, WERE SUSTAINED IN THE ABSENCE OF CONTINUOUS IL-1BETA EXPOSURE. WE REFERRED TO THIS PHENOMENON AS EMT MEMORY. UTILIZING A DOXYCYCLINE-CONTROLLED SLUG EXPRESSION SYSTEM, WE FOUND THAT HIGH EXPRESSION OF THE TRANSCRIPTION FACTOR SLUG WAS INDISPENSABLE FOR THE ESTABLISHMENT OF EMT MEMORY. HIGH SLUG EXPRESSION IN TUMORS OF LUNG CANCER PATIENTS WAS ASSOCIATED WITH POOR SURVIVAL. CHEMICAL OR GENETIC INHIBITION OF SLUG UPREGULATION PREVENTED EMT FOLLOWING THE ACUTE IL-1BETA EXPOSURE BUT DID NOT REVERSE EMT MEMORY. CHROMATIN IMMUNOPRECIPITATION AND METHYLATION-SPECIFIC PCR FURTHER REVEALED A SLUG-MEDIATED TEMPORAL REGULATION OF EPIGENETIC MODIFICATIONS, INCLUDING ACCUMULATION OF H3K27, H3K9, AND DNA METHYLATION, IN THE CDH1 (E-CADHERIN) PROMOTER FOLLOWING THE CHRONIC IL-1BETA EXPOSURE. CHEMICAL INHIBITION OF DNA METHYLATION NOT ONLY RESTORED E-CADHERIN EXPRESSION IN EMT MEMORY, BUT ALSO PRIMED CELLS FOR CHEMOTHERAPY-INDUCED APOPTOSIS. 2020 15 2774 40 EXTRACELLULAR SUPEROXIDE DISMUTASE (EC-SOD) REGULATES GENE METHYLATION AND CARDIAC FIBROSIS DURING CHRONIC HYPOXIC STRESS. CHRONIC HYPOXIC STRESS INDUCES EPIGENETIC MODIFICATIONS MAINLY DNA METHYLATION IN CARDIAC FIBROBLASTS, INACTIVATING TUMOR SUPPRESSOR GENES (RASSF1A) AND ACTIVATING KINASES (ERK1/2) LEADING TO FIBROBLAST PROLIFERATION AND CARDIAC FIBROSIS. THE RAS/ERK SIGNALING PATHWAY IS AN INTRACELLULAR SIGNAL TRANSDUCTION CRITICALLY INVOLVED IN FIBROBLAST PROLIFERATION. RASSF1A FUNCTIONS THROUGH ITS EFFECT ON DOWNSTREAM ERK1/2. THE ANTIOXIDANT ENZYME, EXTRACELLULAR SUPEROXIDE DISMUTASE (EC-SOD), DECREASES OXIDATIVE STRESS FROM CHRONIC HYPOXIA, BUT ITS EFFECTS ON THESE EPIGENETIC CHANGES HAVE NOT BEEN FULLY EXPLORED. TO TEST OUR HYPOTHESIS, WE USED AN IN-VITRO MODEL: WILD-TYPE C57B6 MALE MICE (WT) AND TRANSGENIC MALES WITH AN EXTRA COPY OF HUMAN HEC-SOD (TG). THE STUDIED ANIMALS WERE HOUSED IN HYPOXIA (10% O(2)) FOR 21 DAYS. THE RIGHT VENTRICULAR TISSUE WAS STUDIED FOR CARDIAC FIBROSIS MARKERS USING RT-PCR AND WESTERN BLOT ANALYSES. PRIMARY C57BL6 MOUSE CARDIAC FIBROBLAST TISSUE CULTURE WAS USED TO STUDY THE IN-VITRO MODEL, THE DOWNSTREAM EFFECTS OF RASSF-1 EXPRESSION AND METHYLATION, AND ITS RELATION TO ERK1/2. OUR FINDINGS SHOWED A SIGNIFICANT INCREASE IN CARDIAC FIBROSIS MARKERS: COLLAGEN 1, ALPHA SMOOTH MUSCLE ACTIN (ASMA), AND SNAIL, IN THE WT HYPOXIC ANIMALS AS COMPARED TO THE TG HYPOXIC GROUP (P < 0.05). THE EXPRESSION OF DNA METHYLATION ENZYMES (DNMT 1&3B) WAS SIGNIFICANTLY INCREASED IN THE WT HYPOXIC MICE AS COMPARED TO THE HYPOXIC TG MICE (P < 0.001). RASSF1A EXPRESSION WAS SIGNIFICANTLY LOWER AND ERK1/2 WAS SIGNIFICANTLY HIGHER IN HYPOXIA WT COMPARED TO THE HYPOXIC TG GROUP (P < 0.05). USE OF SIRNA TO BLOCK RASSF1A GENE EXPRESSION IN MURINE CARDIAC FIBROBLAST TISSUE CULTURE LED TO INCREASED FIBROBLAST PROLIFERATION (P < 0.05). METHYLATION OF THE RASSF1A PROMOTER REGION WAS SIGNIFICANTLY REDUCED IN THE TG HYPOXIC GROUP COMPARED TO THE WT HYPOXIC GROUP (0.59 VS. 0.75, RESPECTIVELY). BASED ON OUR FINDINGS, WE CAN SPECULATE THAT EC-SOD SIGNIFICANTLY ATTENUATES RASSF1A GENE METHYLATION AND CAN ALLEVIATE CARDIAC FIBROSIS INDUCED BY HYPOXIA. 2021 16 699 42 BROMODOMAIN PROTEIN 4 IS A KEY MOLECULAR DRIVER OF TGFBETA1-INDUCED HEPATIC STELLATE CELL ACTIVATION. LIVER FIBROSIS IS CHARACTERIZED BY THE EXCESSIVE DEPOSITION OF EXTRACELLULAR MATRIX IN LIVER. CHRONIC LIVER INJURY INDUCES THE ACTIVATION OF HEPATIC STELLATE CELL (HSCS), A KEY STEP IN LIVER FIBROGENESIS. THE ACTIVATED HSC IS THE PRIMARY SOURCE OF ECM AND CONTRIBUTES SIGNIFICANTLY TO LIVER FIBROSIS. TGFBETA1 IS THE MOST POTENT PRO-FIBROTIC CYTOKINE. BROMODOMAIN PROTEIN 4 (BRD4), AN EPIGENETIC READER OF HISTONE ACETYLATION MARKS, WAS CRUCIAL FOR PROFIBROTIC GENE EXPRESSION IN HSCS. THE PRESENT STUDY AIMED TO INVESTIGATE THE ROLES OF BRD4 IN TGFBETA1-DEPENDENT HSC ACTIVATION AND LIVER FIBROSIS, FOCUSING ON TGFBETA1-INDUCED ALTERATIONS OF THE LEVELS OF THE FIBROTIC-RELATED IMPORTANT PROTEINS IN HSCS BY EMPLOYING THE HETEROZYGOUS TGFBETA1 KNOCKOUT MICE AND BRD4 KNOCKDOWN IN VIVO AND IN VITRO. RESULTS REVEALED THAT BRD4 PROTEIN LEVEL WAS SIGNIFICANTLY UPREGULATED BY TGFBETA1 AND BRD4 KNOCKDOWN REDUCED TGFBETA1-INDUCED HSC ACTIVATION AND LIVER FIBROSIS. BRD4 WAS REQUIRED FOR THE INFLUENCES OF TGFBETA1 ON PDGFBETA RECEPTOR AND ON THE PATHWAYS OF SMAD3, STAT3, AND AKT. BRD4 ALSO MEDIATED TGFBETA1-INDUCED INCREASES IN HISTONE ACETYLTRANSFERASE P300, THE PIVOTAL PRO-INFLAMMATORY NFKB P65, AND TISSUE INHIBITOR OF METALLOPROTEINASE 1 WHEREAS BRD4 REDUCED CASPASE-3 PROTEIN LEVELS IN HSCS DURING LIVER INJURY, INDEPENDENT OF TGFBETA1. FURTHER EXPERIMENTS INDICATED THE INTERACTION BETWEEN TGFBETA1-INDUCED BRD4 AND NFKB P65 IN HSCS AND IN LIVER OF TAA-INDUCED LIVER INJURY. HUMAN CIRRHOTIC LIVERS WERE DEMONSTRATED A PARALLEL INCREASE IN THE PROTEIN LEVELS OF BRD4 AND NFKB P65 IN HSCS. THIS STUDY REVEALED THAT BRD4 WAS A KEY MOLECULAR DRIVER OF TGFBETA1-INDUCED HSC ACTIVATION AND LIVER FIBROSIS. 2023 17 1905 37 ENHANCER OF ZESTE HOMOLOG 2 CONTRIBUTES TO APOPTOSIS BY INACTIVATING JANUS KINASE 2/ SIGNAL TRANSDUCER AND ACTIVATOR OF TRANSCRIPTION SIGNALING IN INFLAMMATORY BOWEL DISEASE. BACKGROUND: INFLAMMATORY BOWEL DISEASE (IBD) IS A PREVALENT WORLDWIDE HEALTH PROBLEM FEATURED BY RELAPSING, CHRONIC GASTROINTESTINAL INFLAMMATION. ENHANCER OF ZESTE HOMOLOG 2 (EZH2) IS A CRITICAL EPIGENETIC REGULATOR IN DIFFERENT PATHOLOGICAL MODELS, SUCH AS CANCER AND INFLAMMATION. HOWEVER, THE ROLE OF EZH2 IN THE IBD DEVELOPMENT IS STILL OBSCURE. AIM: TO EXPLORE THE EFFECT OF EZH2 ON IBD PROGRESSION AND THE UNDERLYING MECHANISM. METHODS: THE IBD MOUSE MODEL WAS CONDUCTED BY ADDING DEXTRAN SODIUM SULFATE (DSS), AND THE EFFECT OF EZH2 ON DSS-INDUCED COLITIS WAS ASSESSED IN THE MODEL. THE FUNCTION OF EZH2 IN REGULATING APOPTOSIS AND PERMEABILITY WAS EVALUATED BY ANNEXIN V-FITC APOPTOSIS DETECTION KIT, TRANSEPITHELIAL ELECTRICAL RESISTANCE ANALYSIS, AND WESTERN BLOT ANALYSIS OF RELATED MARKERS, INCLUDING ZONA OCCLUDENS 1, CLAUDIN-5, AND OCCLUDIN, IN NCM460 AND FETAL HUMAN COLON (FHC) CELLS. THE MECHANICAL INVESTIGATION WAS PERFORMED BY QUANTITATIVE REVERSE TRANSCRIPTION-POLYMERASE CHAIN REACTION, WESTERN BLOT ANALYSIS, AND CHROMATIN IMMUNOPRECIPITATION ASSAYS. RESULTS: THE COLON LENGTH WAS INHIBITED IN THE DSS-TREATED MICE AND WAS ENHANCED BY THE EZH2 DEPLETION IN THE SYSTEM. DSS TREATMENT CAUSED A DECREASED HISTOLOGICAL SCORE IN THE MICE, WHICH WAS REVERSED BY EZH2 DEPLETION. THE INFLAMMATORY CYTOKINES, SUCH AS TUMOR NECROSIS FACTOR-ALPHA, INTERLEUKIN-6, AND INTERLEUKIN-1BETA, WERE INDUCED IN THE DSS-TREATED MICE, IN WHICH THE DEPLETION OF EZH2 COULD REVERSE THIS EFFECT. MOREOVER, THE TUMOR NECROSIS FACTOR-ALPHA TREATMENT INDUCED THE APOPTOSIS OF NCM460 AND FHC CELLS, IN WHICH EZH2 DEPLETION COULD REVERSE THIS EFFECT IN THE CELLS. MOREOVER, THE DEPLETION OF EZH2 ATTENUATED PERMEABILITY OF COLONIC EPITHELIAL CELLS. MECHANICALLY, THE DEPLETION OF EZH2 OR EZH2 INHIBITOR GSK343 WAS ABLE TO ENHANCE THE EXPRESSION AND THE PHOSPHORYLATION OF JANUS KINASE 2 (JK2) AND SIGNAL TRANSDUCER AND ACTIVATOR OF TRANSCRIPTION IN THE NCM460 AND FHC CELLS. SPECIFICALLY, EZH2 INACTIVATED JAK2 EXPRESSION BY REGULATING HISTONE H3K27ME3. JAK2 INHIBITOR TG101348 WAS ABLE TO REVERSE EZH2 KNOCKDOWN-MEDIATED COLONIC EPITHELIAL CELL PERMEABILITY AND APOPTOSIS. CONCLUSION: THUS, WE CONCLUDED THAT EZH2 CONTRIBUTED TO APOPTOSIS AND INFLAMMATORY RESPONSE BY INACTIVATING JAK2/ SIGNAL TRANSDUCER AND ACTIVATOR OF TRANSCRIPTION SIGNALING IN IBD. EZH2 MAY BE APPLIED AS A POTENTIAL TARGET FOR IBD THERAPY. 2021 18 3795 33 INTERLEUKIN-6 CONTRIBUTES TO GROWTH IN CHOLANGIOCARCINOMA CELLS BY ABERRANT PROMOTER METHYLATION AND GENE EXPRESSION. THE ASSOCIATION BETWEEN CHRONIC INFLAMMATION AND THE DEVELOPMENT AND PROGRESSION OF MALIGNANCY IS EXEMPLIFIED IN THE BILIARY TRACT WHERE PERSISTENT INFLAMMATION STRONGLY PREDISPOSES TO CHOLANGIOCARCINOMA. THE INFLAMMATORY CYTOKINE INTERLEUKIN-6 (IL-6) ENHANCES TUMOR GROWTH IN CHOLANGIOCARCINOMA BY ALTERED GENE EXPRESSION VIA AUTOCRINE MECHANISMS. IL-6 CAN REGULATE THE ACTIVITY OF DNA METHYLTRANSFERASES, AND MOREOVER, ABERRANT DNA METHYLATION CAN CONTRIBUTE TO CARCINOGENESIS. WE THEREFORE INVESTIGATED THE EFFECT OF CHRONIC EXPOSURE TO IL-6 ON METHYLATION-DEPENDENT GENE EXPRESSION AND TRANSFORMED CELL GROWTH IN HUMAN CHOLANGIOCARCINOMA. THE RELATIONSHIP BETWEEN AUTOCRINE IL-6 PATHWAYS, DNA METHYLATION, AND TRANSFORMED CELL GROWTH WAS ASSESSED USING MALIGNANT CHOLANGIOCYTES STABLY TRANSFECTED TO OVEREXPRESS IL-6. TREATMENT WITH THE DNA METHYLATION INHIBITOR 5-AZA-2'-DEOXYCYTIDINE DECREASED CELL PROLIFERATION, GROWTH IN SOFT AGAR, AND METHYLCYTOSINE CONTENT OF MALIGNANT CHOLANGIOCYTES. HOWEVER, THIS EFFECT WAS NOT OBSERVED IN IL-6-OVEREXPRESSING CELLS. IL-6 OVEREXPRESSION RESULTED IN THE ALTERED EXPRESSION AND PROMOTER METHYLATION OF SEVERAL GENES, INCLUDING THE EPIDERMAL GROWTH FACTOR RECEPTOR (EGFR). EGFR PROMOTER METHYLATION WAS DECREASED AND GENE AND PROTEIN EXPRESSION WAS INCREASED BY IL-6. THUS, EPIGENETIC REGULATION OF GENE EXPRESSION BY IL-6 CAN CONTRIBUTE TO TUMOR PROGRESSION BY ALTERING PROMOTER METHYLATION AND GENE EXPRESSION OF GROWTH-REGULATORY PATHWAYS, SUCH AS THOSE INVOLVING EGFR. MOREOVER, ENHANCED IL-6 EXPRESSION MAY DECREASE THE SENSITIVITY OF TUMOR CELLS TO THERAPEUTIC TREATMENTS USING METHYLATION INHIBITORS. THESE OBSERVATIONS HAVE IMPORTANT IMPLICATIONS FOR CANCER TREATMENT AND PROVIDE A MECHANISM BY WHICH PERSISTENT CYTOKINE STIMULATION CAN PROMOTE TUMOR GROWTH. 2006 19 1272 45 CYTOTOXIC ACTIVITY OF VALPROIC ACID ON PRIMARY CHRONIC LYMPHOCYTIC LEUKEMIA CELLS. BACKGROUND: CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) IS THE MOST COMMON ADULT LEUKEMIA IN WESTERN CIVILIZATION. THE ACCUMULATION OF CD5+CD19+ B LYMPHOCYTES IN PERIPHERAL BLOOD IS DUE TO A DEFECT IN THE APOPTOTIC PATHWAY RATHER THAN EXCESSIVE PROLIFERATION IN THE BONE MARROW AND LYMPH NODES. DESPITE A NUMBER OF TREATMENTS, CLL REMAINS AN INCURABLE DISEASE. VALPROIC ACID (VPA) ACTIVITY, AS A HISTONE DEACETYLASE INHIBITOR, COULD RESTORE THE EPIGENETIC CHANGES UNDERLYING THE PATHOGENESIS OF CLL AND THUS INDUCE CELL DEATH. OBJECTIVES: IN THE PRESENT STUDY WE HYPOTHESIZED THAT VPA COULD INDUCE CLL PRIMARY CELLS DEATH THROUGH ACTIVATION OF APOPTOSIS. MATERIAL AND METHODS: PERIPHERAL BLOOD SAMPLES WERE OBTAINED FROM 53 CLL PATIENTS. PERIPHERAL BLOOD MONONUCLEAR CELLS WERE ISOLATED THROUGH DENSITY GRADIENT CENTRIFUGATION AND WERE THE SUBJECT OF A 24-HOUR CELL CULTURE WITH 10 MM OF VPA. THE CYTOTOXIC EFFECT OF VPA WAS EVALUATED WITH AN XTT TEST AND THEREAFTER CONFIRMED USING ANNEXIN V-FITC/PI STAINING AND FLOW CYTOMETRY TECHNIQUES. RESULTS: IN THIS STUDY, A MEDIAN VPA CYTOTOXICITY OF 13.88% WITH A RANGE OF 0-54.65% WAS OBSERVED. ANNEXIN V/PI STAINING CONFIRMED THAT THE DEMONSTRATED CYTOTOXICITY WAS CAUSED BY INCREASED APOPTOSIS IN THE VPA TREATED CELLS AS COMPARED TO CONTROL CELLS. STATISTICAL ANALYSIS SHOWED THAT VPA'S EFFECT ON CLL CELLS DEPENDS ON LACTATE DEHYDROGENASE SERUM LEVELS, BUT IS INDEPENDENT OF ALL OTHER PROGNOSTIC MARKERS. CONCLUSIONS: THE RESULTS OF THE PRESENT EXPERIMENTS FOUND THAT VPA AT A CLINICALLY APPLICABLE CONCENTRATION SIGNIFICANTLY INDUCES APOPTOSIS INDEPENDENTLY OF THE DISEASE STAGE AND MIGHT BE A VALUABLE THERAPEUTIC AGENT FOR ALL CLL PATIENTS. 2015 20 3935 39 LIVER-SPECIFIC KNOCKDOWN OF CLASS IIA HDACS HAS LIMITED EFFICACY ON GLUCOSE METABOLISM BUT ENTAILS SEVERE ORGAN SIDE EFFECTS IN MICE. HISTONE DEACETYLASES (HDACS) ARE IMPORTANT REGULATORS OF EPIGENETIC GENE MODIFICATION THAT ARE INVOLVED IN THE TRANSCRIPTIONAL CONTROL OF METABOLISM. IN PARTICULAR CLASS IIA HDACS HAVE BEEN SHOWN TO AFFECT HEPATIC GLUCONEOGENESIS AND PREVIOUS APPROACHES REVEALED THAT THEIR INHIBITION REDUCES BLOOD GLUCOSE IN TYPE 2 DIABETIC MICE. IN THE PRESENT STUDY, WE AIMED TO EVALUATE THE POTENTIAL OF CLASS IIA HDAC INHIBITION AS A THERAPEUTIC OPPORTUNITY FOR THE TREATMENT +OF METABOLIC DISEASES. FOR THAT, SIRNAS SELECTIVELY TARGETING HDAC4, 5 AND 7 WERE SELECTED AND USED TO ACHIEVE A COMBINATORIAL KNOCKDOWN OF THESE THREE CLASS IIA HDAC ISOFORMS. SUBSEQUENTLY, THE HEPATOCELLULAR EFFECTS AS WELL AS THE IMPACT ON GLUCOSE AND LIPID METABOLISM WERE ANALYZED IN VITRO AND IN VIVO. THE TRIPLE KNOCKDOWN RESULTED IN A STATISTICALLY SIGNIFICANT DECREASE OF GLUCONEOGENIC GENE EXPRESSION IN MURINE AND HUMAN HEPATOCYTE CELL MODELS. A SIMILAR HDAC-INDUCED DOWNREGULATION OF HEPATIC GLUCONEOGENESIS GENES COULD BE ACHIEVED IN MICE USING A LIVER-SPECIFIC LIPID NANOPARTICLE SIRNA FORMULATION. HOWEVER, THE EFFICACY ON WHOLE BODY GLUCOSE METABOLISM ASSESSED BY PYRUVATE-TOLERANCE TESTS WERE ONLY LIMITED AND DID NOT OUTWEIGH THE SAFETY FINDINGS OBSERVED BY HISTOPATHOLOGICAL ANALYSIS IN SPLEEN AND KIDNEY. MECHANISTICALLY, AFFYMETRIX GENE EXPRESSION STUDIES PROVIDE EVIDENCE THAT CLASS IIA HDACS DIRECTLY TARGET OTHER KEY FACTORS BEYOND THE DESCRIBED FORKHEAD BOX (FOXP) TRANSCRIPTION REGULATORS, SUCH AS HEPATOCYTE NUCLEAR FACTOR 4 ALPHA (HNF4A). DOWNSTREAM OF THESE FACTORS SEVERAL ADDITIONAL PATHWAYS WERE REGULATED NOT MERELY INCLUDING GLUCOSE AND LIPID METABOLISM AND TRANSPORT. IN CONCLUSION, THE LIVER-DIRECTED COMBINATORIAL KNOCKDOWN OF HDAC4, 5 AND 7 BY THERAPEUTIC SIRNAS AFFECTED MULTIPLE PATHWAYS IN VITRO, LEADING IN VIVO TO THE DOWNREGULATION OF GENES INVOLVED IN GLUCONEOGENESIS. HOWEVER, THE EFFECTS ON GENE EXPRESSION LEVEL WERE NOT PARALLELED BY A SIGNIFICANT REDUCTION OF GLUCONEOGENESIS IN MICE. COMBINED KNOCKDOWN OF HDAC ISOFORMS WAS ASSOCIATED WITH SEVERE ADVERSE EFFECTS IN VIVO, CHALLENGING THIS APPROACH AS A TREATMENT OPTION FOR CHRONIC METABOLIC DISORDERS LIKE TYPE 2 DIABETES. 2020