1 1945 130 EPIGALLOCATECHIN-3-GALLATE, A HISTONE ACETYLTRANSFERASE INHIBITOR, INHIBITS EBV-INDUCED B LYMPHOCYTE TRANSFORMATION VIA SUPPRESSION OF RELA ACETYLATION. BECAUSE THE P300/CBP-MEDIATED HYPERACETYLATION OF RELA (P65) IS CRITICAL FOR NUCLEAR FACTOR-KAPPAB (NF-KAPPAB) ACTIVATION, THE ATTENUATION OF P65 ACETYLATION IS A POTENTIAL MOLECULAR TARGET FOR THE PREVENTION OF CHRONIC INFLAMMATION. DURING OUR ONGOING SCREENING STUDY TO IDENTIFY NATURAL COMPOUNDS WITH HISTONE ACETYLTRANSFERASE INHIBITOR (HATI) ACTIVITY, WE IDENTIFIED EPIGALLOCATECHIN-3-GALLATE (EGCG) AS A NOVEL HATI WITH GLOBAL SPECIFICITY FOR THE MAJORITY OF HAT ENZYMES BUT WITH NO ACTIVITY TOWARD EPIGENETIC ENZYMES INCLUDING HDAC, SIRT1, AND HMTASE. AT A DOSE OF 100 MICROMOL/L, EGCG ABROGATES P300-INDUCED P65 ACETYLATION IN VITRO AND IN VIVO, INCREASES THE LEVEL OF CYTOSOLIC IKAPPABALPHA, AND SUPPRESSES TUMOR NECROSIS FACTOR ALPHA (TNFALPHA)-INDUCED NF-KAPPAB ACTIVATION. WE ALSO SHOWED THAT EGCG PREVENTS TNFALPHA-INDUCED P65 TRANSLOCATION TO THE NUCLEUS, CONFIRMING THAT HYPERACETYLATION IS CRITICAL FOR NF-KAPPAB TRANSLOCATION AS WELL AS ACTIVITY. FURTHERMORE, EGCG TREATMENT INHIBITED THE ACETYLATION OF P65 AND THE EXPRESSION OF NF-KAPPAB TARGET GENES IN RESPONSE TO DIVERSE STIMULI. FINALLY, EGCG REDUCED THE BINDING OF P300 TO THE PROMOTER REGION OF INTERLEUKIN-6 GENE WITH AN INCREASED RECRUITMENT OF HDAC3, WHICH HIGHLIGHTS THE IMPORTANCE OF THE BALANCE BETWEEN HATS AND HISTONE DEACETYLASES IN THE NF-KAPPAB-MEDIATED INFLAMMATORY SIGNALING PATHWAY. IMPORTANTLY, EGCG AT 50 MICROMOL/L DOSE COMPLETELY BLOCKS EBV INFECTION-INDUCED CYTOKINE EXPRESSION AND SUBSEQUENTLY THE EBV-INDUCED B LYMPHOCYTE TRANSFORMATION. THESE RESULTS SHOW THE CRUCIAL ROLE OF ACETYLATION IN THE DEVELOPMENT OF INFLAMMATORY-RELATED DISEASES. 2009 2 5868 35 SUPPRESSIVE EFFECTS OF METFORMIN ON T-HELPER 1-RELATED CHEMOKINES EXPRESSION IN THE HUMAN MONOCYTIC LEUKEMIA CELL LINE THP-1. PURPOSE OF THE STUDY: TYPE 1 AND TYPE 2 DIABETES MELLITUS (DM) ARE CHRONIC T-CELL-MEDIATED INFLAMMATORY DISEASES. METFORMIN IS A WIDELY USED DRUG FOR TYPE 2 DM THAT REDUCES THE NEED FOR INSULIN IN TYPE 1 DM. HOWEVER, WHETHER METFORMIN HAS AN ANTI-INFLAMMATORY EFFECT FOR TREATING DM IS UNKNOWN. WE INVESTIGATED THE ANTI-INFLAMMATORY MECHANISM OF METFORMIN IN THE HUMAN MONOCYTIC LEUKEMIA CELL LINE THP-1. MATERIALS AND METHODS: THE HUMAN MONOCYTIC LEUKEMIA CELL LINE THP-1 WAS PRETREATED WITH METFORMIN AND STIMULATED WITH LIPOPOLYSACCHARIDE (LPS). THE PRODUCTION OF T-HELPER (TH)-1-RELATED CHEMOKINES INCLUDING INTERFERON-GAMMA-INDUCED PROTEIN-10 (IP-10) AND MONOCYTE CHEMOATTRACTANT PROTEIN-1 (MCP-1), TH2-RELATED CHEMOKINE MACROPHAGE-DERIVED CHEMOKINE, AND THE PROINFLAMMATORY CHEMOKINE TUMOR NECROSIS FACTOR-ALPHA WAS MEASURED USING ENZYME-LINKED IMMUNOSORBENT ASSAY. INTRACELLULAR SIGNALING PATHWAYS WERE INVESTIGATED USING WESTERN BLOT ANALYSIS AND CHROMATIN IMMUNOPRECIPITATION ASSAY. RESULTS: METFORMIN SUPPRESSED LPS-INDUCED IP-10 AND MCP-1 PRODUCTION AS WELL AS LPS-INDUCED PHOSPHORYLATION OF C-JUN N-TERMINAL KINASE (JNK), P38, EXTRACELLULAR SIGNAL-REGULATED KINASE (ERK), AND NUCLEAR FACTOR-KAPPA B (NF-KAPPAB). MOREOVER, METFORMIN SUPPRESSED LPS-INDUCED ACETYLATION OF HISTONES H3 AND H4 AT THE IP-10 PROMOTER. CONCLUSIONS: METFORMIN SUPPRESSED THE PRODUCTION OF TH1-RELATED CHEMOKINES IP-10 AND MCP-1 IN THP-1 CELLS. SUPPRESSIVE EFFECTS OF METFORMIN ON IP-10 PRODUCTION MIGHT BE ATTRIBUTED AT LEAST PARTIALLY TO THE JNK, P38, ERK, AND NF-KAPPAB PATHWAYS AS WELL AS TO EPIGENETIC REGULATION THROUGH THE ACETYLATION OF HISTONES H3 AND H4. THESE RESULTS INDICATED THE THERAPEUTIC ANTI-INFLAMMATORY POTENTIAL OF METFORMIN. 2018 3 1906 39 ENHANCER OF ZESTE HOMOLOG 2-CATALYSED H3K27 TRIMETHYLATION PLAYS A KEY ROLE IN ACUTE-ON-CHRONIC LIVER FAILURE VIA TNF-MEDIATED PATHWAY. ACUTE-ON-CHRONIC LIVER FAILURE IS MAINLY DUE TO HOST IMMUNITY SELF-DESTRUCTION. THE HISTONE H3 LYSINE 27 (H3K27) TRIMETHYLATING ENZYME, ENHANCER OF ZESTE HOMOLOG 2 (EZH2) MEDIATES EPIGENETIC SILENCING OF GENE EXPRESSION AND REGULATES IMMUNITY, ALSO INVOLVES PATHOGENESIS OF SEVERAL LIVER DISEASES. THE CURRENT STUDY WAS TO DETERMINE THE ROLE OF METHYLTRANSFERASE EZH2 AND ITS CATALYSED H3K27 TRIMETHYLATION (H3K27ME3) IN LIVER FAILURE, AND TO FURTHER INVESTIGATE THE POTENTIAL TARGET FOR LIVER FAILURE TREATMENT. EZH2 AND ITS CATALYSED H3K27ME3 WERE DETERMINED IN PERIPHERAL BLOOD MONONUCLEAR CELLS (PBMC) FROM LIVER FAILURE PATIENTS AND KUPFFER CELLS FROM EXPERIMENTAL MICE. FURTHERMORE, GSK126 (AN INHIBITOR FOR EZH2 TRIMETHYLATION FUNCTION) WAS APPLIED IN LIVER FAILURE MICE IN VIVO, AND LIPOPOLYSACCHARIDE-STIMULATED MONONUCLEAR CELLS IN VITRO. EZH2 AND H3K27ME3 WERE SIGNIFICANTLY UPREGULATED IN HUMAN PBMC FROM LIVER FAILURE PATIENTS OR MURINE KUPFFER CELLS FROM THE LIVER FAILURE ANIMALS, RESPECTIVELY. GSK126 AMELIORATED DISEASE SEVERITY IN LIVER FAILURE MICE, WHICH MAYBE ATTRIBUTE TO DOWN-REGULATE CIRCULATING AND HEPATIC PROINFLAMMATORY CYTOKINES, ESPECIALLY TNF VIA REDUCING H3K27ME3. IN-DEPTH CHROMATIN IMMUNOPRECIPITATION ANALYSIS UNRAVELLED THAT DECREASED ENRICHMENT OF H3K27ME3 ON TNF PROMOTOR, RESULTING IN TNF ELEVATION IN KUPFFER CELLS FROM LIVER FAILURE MICE. NUCLEAR FACTOR KAPPA B (NF-KAPPAB) AND PROTEIN KINASE B (AKT) SIGNALLING PATHWAYS WERE ACTIVATED UPON LIPOPOLYSACCHARIDE STIMULATION, BUT ATTENUATED BY USING GSK126, ACCOMPANIED WITH DECREASED TNF IN VITRO. IN CONCLUSION, EZH2 AND H3K27ME3 CONTRIBUTED TO THE PATHOGENESIS OF LIVER FAILURE VIA TRIGGERING TNF AND OTHER INDISPENSABLE PROINFLAMMATORY CYTOKINES. EZH2 WAS TO MODIFY H3K27ME3 ENRICHMENT, AS WELL AS, ACTIVATION OF THE DOWNSTREAM NF-KAPPAB AND AKT SIGNALLING PATHWAYS. 2018 4 5860 39 SULFORAPHANE PREVENTS ANGIOTENSIN II-INDUCED CARDIOMYOPATHY BY ACTIVATION OF NRF2 THROUGH EPIGENETIC MODIFICATION. NUCLEAR FACTOR ERYTHROID 2-RELATED FACTOR (NRF2) IS AN IMPORTANT REGULATOR OF CELLULAR ANTIOXIDANT DEFENCE. WE PREVIOUSLY SHOWED THAT SFN PREVENTED ANG II-INDUCED CARDIAC DAMAGE VIA ACTIVATION OF NRF2. HOWEVER, THE UNDERLYING MECHANISM OF SFN'S PERSISTENT CARDIAC PROTECTION REMAINS UNCLEAR. THIS STUDY AIMED TO EXPLORE THE POTENTIAL OF SFN IN ACTIVATING CARDIAC NRF2 THROUGH EPIGENETIC MECHANISMS. WILD-TYPE MICE WERE INJECTED SUBCUTANEOUSLY WITH ANG II, WITH OR WITHOUT SFN. ADMINISTRATION OF CHRONIC ANG II-INDUCED CARDIAC INFLAMMATORY FACTOR EXPRESSION, OXIDATIVE DAMAGE, FIBROSIS AND CARDIAC REMODELLING AND DYSFUNCTION, ALL OF WHICH WERE EFFECTIVELY IMPROVED BY SFN TREATMENT, COUPLED WITH AN UP-REGULATION OF NRF2 AND DOWNSTREAM GENES. BISULFITE GENOME SEQUENCING AND CHROMATIN IMMUNOPRECIPITATION (CHIP) WERE PERFORMED TO DETECT THE METHYLATION LEVEL OF THE FIRST 15 CPGS AND HISTONE H3 ACETYLATION (AC-H3) STATUS IN THE NRF2 PROMOTER REGION, RESPECTIVELY. THE RESULTS SHOWED THAT SFN REDUCED ANG II-INDUCED CPG HYPERMETHYLATION AND PROMOTED AC-H3 ACCUMULATION IN THE NRF2 PROMOTER REGION, ACCOMPANIED BY THE INHIBITION OF GLOBAL DNMT AND HDAC ACTIVITY, AND A DECREASED PROTEIN EXPRESSION OF KEY DNMT AND HDAC ENZYMES. TAKEN TOGETHER, SFN EXERTS ITS CARDIOPROTECTIVE EFFECT THROUGH EPIGENETIC MODIFICATION OF NRF2, WHICH MAY PARTIALLY CONTRIBUTE TO LONG-TERM ACTIVATION OF CARDIAC NRF2. 2021 5 5795 37 STAT3 INDUCTION OF MIR-146B FORMS A FEEDBACK LOOP TO INHIBIT THE NF-KAPPAB TO IL-6 SIGNALING AXIS AND STAT3-DRIVEN CANCER PHENOTYPES. INTERLEUKIN-6 (IL-6)-MEDIATED ACTIVATION OF SIGNAL TRANSDUCER AND ACTIVATOR OF TRANSCRIPTION 3 (STAT3) IS A MECHANISM BY WHICH CHRONIC INFLAMMATION CAN CONTRIBUTE TO CANCER AND IS A COMMON ONCOGENIC EVENT. WE DISCOVERED A PATHWAY, THE LOSS OF WHICH IS ASSOCIATED WITH PERSISTENT STAT3 ACTIVATION IN HUMAN CANCER. WE FOUND THAT THE GENE ENCODING THE TUMOR SUPPRESSOR MICRORNA MIR-146B IS A DIRECT STAT3 TARGET GENE, AND ITS EXPRESSION WAS INCREASED IN NORMAL BREAST EPITHELIAL CELLS BUT DECREASED IN TUMOR CELLS. METHYLATION OF THE MIR-146B PROMOTER, WHICH INHIBITED STAT3-MEDIATED INDUCTION OF EXPRESSION, WAS INCREASED IN PRIMARY BREAST CANCERS. MOREOVER, WE FOUND THAT MIR-146B INHIBITED NUCLEAR FACTOR KAPPAB (NF-KAPPAB)-DEPENDENT PRODUCTION OF IL-6, SUBSEQUENT STAT3 ACTIVATION, AND IL-6/STAT3-DRIVEN MIGRATION AND INVASION IN BREAST CANCER CELLS, THEREBY ESTABLISHING A NEGATIVE FEEDBACK LOOP. IN ADDITION, HIGHER EXPRESSION OF MIR-146B WAS POSITIVELY CORRELATED WITH PATIENT SURVIVAL IN BREAST CANCER SUBTYPES WITH INCREASED IL6 EXPRESSION AND STAT3 PHOSPHORYLATION. OUR RESULTS IDENTIFY AN EPIGENETIC MECHANISM OF CROSSTALK BETWEEN STAT3 AND NF-KAPPAB RELEVANT TO CONSTITUTIVE STAT3 ACTIVATION IN MALIGNANCY AND THE ROLE OF INFLAMMATION IN ONCOGENESIS. 2014 6 5227 37 PRMT6 MEDIATES INFLAMMATION VIA ACTIVATION OF THE NF-KAPPAB/P65 PATHWAY ON A CIGARETTE SMOKE EXTRACT-INDUCED MURINE EMPHYSEMA MODEL. INTRODUCTION: SMOKE-DRIVEN LUNG INFLAMMATION IS CONSIDERED TO BE THE MAJOR PATHOPHYSIOLOGY MECHANISM OF CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD)/EMPHYSEMA. PROTEIN ARGININE METHYLTRANSFERASE 6 (PRMT6) IS A KEY EPIGENETIC ENZYME, WHICH IS RELATED TO PROTECTING THE TRI-METHYLATION OF H3K4 (H3K4ME3). WE HYPOTHESIZED THAT PTMT6 PROTECTS LUNG INFLAMMATION THROUGH THE NUCLEAR FACTOR KAPPA B (NF-KAPPAB) PATHWAY. METHODS: MICE WERE INJECTED WITH CIGARETTE SMOKE EXTRACT (CSE) OR PBS TO ESTABLISH A MICE MODEL, INTRATRACHEALLY INSTILLED WITH OVEREXPRESSED PRMT6 OR NEGATIVE CONTROL VECTOR. MORPHOMETRY OF LUNG SLIDES AND LUNG FUNCTION WERE MEASURED. WE DETERMINED THE PROTEIN EXPRESSION OF PRMT6 AND ITS RELATED HISTONE TARGETS, THE ACTIVATION OF NF-KAPPAB PATHWAY, THE LEVEL OF TUMOR NECROSIS FACTOR ALPHA (TNFALPHA) AND INTERLEUKIN-1BETA (IL-1BETA). RESULTS: AFTER PRMT6 OVEREXPRESSION, THE MORPHOMETRY INDEXES AND LUNG FUNCTION WERE IMPROVED. ALSO, THE EXPRESSION OF H3K4ME3 WAS DECREASED. OVEREXPRESSED PRMT6 COULD SUPPRESS CSE-INDUCED NF-KAPPAB ACTIVATION AND PRO-INFLAMMATION GENES EXPRESSION. CONCLUSIONS: THE OVEREXPRESSED PRMT6 COULD SERVE AS AN INFLAMMATION INHIBITOR, POTENTIALLY THROUGH BLOCKING THE NF-KAPPAB/P65 PATHWAY IN THE MURINE EMPHYSEMA MODEL. 2020 7 2784 30 EZH2 PROMOTES EXTRACELLULAR MATRIX DEGRADATION VIA NUCLEAR FACTOR-KAPPAB (NF-KAPPAB) AND P38 SIGNALING PATHWAYS IN PULPITIS. PULPITIS IS A COMPLICATED CHRONIC INFLAMMATORY PROCESS WHICH CAN BE IN A DYNAMIC BALANCE BETWEEN DAMAGE AND REPAIR. THE EXTRACELLULAR MATRIX PLAYS AN IMPORTANT REGULATORY ROLE IN WOUND HEALING AND TISSUE REPAIR. THE AIM OF THIS STUDY WAS TO EXPLORE THE ROLE OF THE EPIGENETIC MARK, ENHANCER OF ZESTE HOMOLOG 2 (EZH2) ON THE DEGRADATION OF EXTRACELLULAR MATRIX DURING PULPITIS. QUANTITATIVE POLYMERASE CHAIN REACTION WAS USED TO ASSESS THE EXPRESSION OF MATRIX METALLOPROTEINASES (MMPS) AND TYPE I COLLAGEN IN HUMAN DENTAL PULP CELLS (HDPCS) UPON EZH2 AND EI1 (EZH2 INHIBITOR) STIMULATION. THE MECHANISM OF EZH2 AFFECTING EXTRACELLULAR MATRIX WAS EXPLORED THROUGH QUANTITATIVE POLYMERASE CHAIN REACTION AND WESTERN BLOT. A RAT MODEL OF DENTAL PULP INFLAMMATION WAS ESTABLISHED, AND THE EXPRESSION OF TYPE I COLLAGEN IN DENTAL PULP UNDER EZH2 STIMULATION WAS DETECTED BY IMMUNOHISTOCHEMICAL STAINING. EZH2 UPREGULATED THE EXPRESSION OF MMP-1, MMP-3, MMP-8, AND MMP-10 AND DECREASED THE PRODUCTION OF TYPE I COLLAGEN IN HDPCS, WHILE EI1 HAD THE OPPOSITE EFFECT. EZH2 ACTIVATED THE NUCLEAR FACTOR-KAPPA B (NF-KAPPAB) AND P38 SIGNALING PATHWAYS IN HDPCS, THE INHIBITION OF WHICH REVERSED THE INDUCTION OF MMPS AND THE SUPPRESSION OF TYPE I COLLAGEN. EZH2 CAN DOWNREGULATE THE TYPE I COLLAGEN LEVELS IN AN EXPERIMENTAL MODEL OF DENTAL PULPITIS IN RATS. EZH2 PROMOTES EXTRACELLULAR MATRIX DEGRADATION VIA NUCLEAR FACTOR-KAPPAB (NF-KAPPAB) AND P38 SIGNALING PATHWAYS IN PULPITIS. EZH2 CAN DECREASE THE TYPE I COLLAGEN LEVELS IN VIVO AND IN VITRO. 2021 8 5479 35 RESVERATROL ATTENUATES CIGARETTE SMOKE EXTRACT INDUCED CELLULAR SENESCENCE IN HUMAN AIRWAY EPITHELIAL CELLS BY REGULATING THE MIR-34A/SIRT1/NF-KAPPAB PATHWAY. CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) IS CHARACTERIZED BY ACCELERATED LUNG AGING. SMOKING IS THE CRITICAL RISK FACTOR FOR COPD. CELLULAR SENESCENCE OF AIRWAY EPITHELIAL CELLS IS THE CYTOLOGICAL BASIS OF ACCELERATED LUNG AGING IN COPD, AND THE REGULATION OF MICRORNAS (MIRNAS) IS THE CENTRAL EPIGENETIC MECHANISM OF CELLULAR SENESCENCE. RESVERATROL (RES) IS A POLYPHENOL WITH ANTI-AGING PROPERTIES. THIS STUDY INVESTIGATED WHETHER RES ATTENUATES CIGARETTE SMOKE EXTRACT (CSE)-INDUCED CELLULAR SENESCENCE IN HUMAN AIRWAY EPITHELIAL CELLS (BEAS-2B) THROUGH THE MIR-34A/SIRT1/NUCLEAR FACTOR-KAPPAB (NF-KAPPAB) PATHWAY. BEAS-2B CELLS WERE TREATED WITH RES, CSE AND TRANSFECTED WITH MIR-34A-5P MIMICS. CELLULAR SENESCENCE WAS EVALUATED BY SENESCENCE -RELATED BETA-GALACTOSIDASE (SA-BETA-GAL) STAINING AND EXPRESSION OF SENESCENCE-RELATED GENES (P16, P21, AND P53). THE EXPRESSIONS OF MIR-34A-5P, SIRT1, AND NF-KAPPAB P65 WERE EXAMINED USING QUANTITATIVE REAL TIME POLYMERASE CHAIN REACTION AND WESTERN BLOTTING. THE SENESCENCE-ASSOCIATED SECRETORY PHENOTYPE (SASP) CYTOKINES (IL-1BETA, IL-6, IL-8, TNF-ALPHA) WERE ASSESSED BY ENZYME-LINKED IMMUNOSORBENT ASSAY. THE BINDING BETWEEN MIR-34A-5P AND SIRT1 WAS CONFIRMED BY DUAL-LUCIFERASE REPORTER ASSAY. THE RESULTS SHOWED THAT CSE DOSE-DEPENDENTLY DECREASED CELL VIABILITY AND ELEVATED CELLULAR SENESCENCE, CHARACTERIZED BY INCREASED SA-BETA-GAL STAINING AND SENESCENCE-RELATED GENE EXPRESSIONS (P16, P21, AND P53). FURTHER, CSE DOSE-DEPENDENTLY INCREASED THE EXPRESSION OF MIR-34A-5P AND SASP CYTOKINES (IL-1BETA, IL-6, IL-8, TNF-ALPHA) IN BEAS-2B CELLS. PRETREATMENT WITH RES INHIBITED CSE-INDUCED CELLULAR SENESCENCE AND SECRETION OF SASP CYTOKINES (IL-1BETA, IL-6, IL-8, TNF-ALPHA) IN A DOSE-DEPENDENT MANNER. MOREOVER, RES REVERSED THE CSE-INDUCED DOWN-REGULATION OF SIRT1 AND UP-REGULATION OF MIR-34A-5P AND NF-KAPPAB P65. SIRT1 IS A TARGET OF MIR-34A-5P. OVEREXPRESSION OF MIR-34A-5P VIA TRANSFECTION WITH MIR-34A-5P MIMIC IN BEAS-2B CELLS ATTENUATED THE INHIBITORY EFFECT OF RES ON CELLULAR SENESCENCE, ACCOMPANIED BY REVERSING THE EXPRESSION OF SIRT1 AND NF-KAPPAB P65. IN CONCLUSION, RES ATTENUATED CSE-INDUCED CELLULAR SENESCENCE IN BEAS-2B CELLS BY REGULATING THE MIR-34A/SIRT1/NF-KAPPAB PATHWAY, WHICH MAY PROVIDE A NEW APPROACH FOR COPD TREATMENT. 2022 9 1667 38 DOWNREGULATION OF PCAF BY MIR-181A/B PROVIDES FEEDBACK REGULATION TO TNF-ALPHA-INDUCED TRANSCRIPTION OF PROINFLAMMATORY GENES IN LIVER EPITHELIAL CELLS. ABERRANT CELLULAR RESPONSES TO PROINFLAMMATORY CYTOKINES, SUCH AS TNF-ALPHA, ARE PATHOGENIC FEATURES IN MOST CHRONIC INFLAMMATORY DISEASES. A VARIETY OF EXTRACELLULAR AND INTRACELLULAR FEEDBACK PATHWAYS HAS EVOLVED TO PREVENT AN INAPPROPRIATE CELLULAR REACTION TO THESE PROINFLAMMATORY CYTOKINES. IN THIS STUDY, WE REPORT THAT TNF-ALPHA TREATMENT OF HUMAN AND MOUSE CHOLANGIOCYTES AND HEPATOCYTES DOWNREGULATED EXPRESSION OF P300/CBP-ASSOCIATED FACTOR (PCAF), A COACTIVATOR AND AN ACETYLTRANSFERASE THAT PROMOTES HISTONE ACETYLATION AND GENE TRANSCRIPTION. OF THESE UPREGULATED MICRORNAS IN TNF-ALPHA-TREATED CELLS, MIR-181A/B (MIR-181A AND MIR-181B) SUPPRESSED TRANSLATION OF PCAF MRNA. FUNCTIONAL MANIPULATION OF MIR-181A/B CAUSED RECIPROCAL ALTERATIONS IN PCAF PROTEIN EXPRESSION IN CULTURED CHOLANGIOCYTES AND HEPATOCYTES. INHIBITION OF MIR-181A/B FUNCTION WITH ANTI-MIRS BLOCKED TNF-ALPHA-INDUCED SUPPRESSION OF PCAF EXPRESSION. PROMOTER RECRUITMENT OF PCAF WAS SHOWN TO BE ASSOCIATED WITH TNF-ALPHA-INDUCED TRANSCRIPTION OF INFLAMMATORY GENES. INTRIGUINGLY, PRETREATMENT OF CELLS WITH TNF-ALPHA INHIBITED TRANSCRIPTION OF INFLAMMATORY GENES IN RESPONSE TO SUBSEQUENT TNF-ALPHA STIMULATION. OVEREXPRESSION OF PCAF OR INHIBITION OF MIR-181A/B FUNCTION WITH ANTI-MIRS ATTENUATED THE INHIBITORY EFFECTS OF TNF-ALPHA PRETREATMENT ON EPITHELIAL INFLAMMATORY RESPONSE TO SUBSEQUENT TNF-ALPHA STIMULATION. DOWNREGULATION OF PCAF AND THE INHIBITORY EFFECTS OF TNF-ALPHA PRETREATMENT ON LIVER EPITHELIAL INFLAMMATORY RESPONSE WERE FURTHER CONFIRMED IN A MOUSE MODEL OF TNF-ALPHA I.P. INJECTION. THESE DATA SUGGEST THAT PCAF IS A TARGET FOR MIR-181A/B, AND DOWNREGULATION OF PCAF BY TNF-ALPHA PROVIDES NEGATIVE FEEDBACK REGULATION TO INFLAMMATORY REACTIONS IN LIVER EPITHELIAL CELLS, A PROCESS THAT MAY BE RELEVANT TO THE EPIGENETIC FINE-TUNING OF EPITHELIAL INFLAMMATORY PROCESSES IN GENERAL. 2012 10 6456 34 THYMOSIN BETA4 PREVENTS OXIDATIVE STRESS, INFLAMMATION, AND FIBROSIS IN ETHANOL- AND LPS-INDUCED LIVER INJURY IN MICE. THYMOSIN BETA 4 (TBETA4), AN ACTIN-SEQUESTERING PROTEIN, IS INVOLVED IN TISSUE DEVELOPMENT AND REGENERATION. IT PREVENTS INFLAMMATION AND FIBROSIS IN SEVERAL TISSUES. WE INVESTIGATED THE ROLE OF TBETA4 IN CHRONIC ETHANOL- AND ACUTE LIPOPOLYSACCHARIDE- (LPS-) INDUCED MOUSE LIVER INJURY. C57BL/6 MICE WERE FED 5% ETHANOL IN LIQUID DIET FOR 4 WEEKS PLUS BINGE ETHANOL (5 G/KG, GAVAGE) WITH OR WITHOUT LPS (2 MG/KG, INTRAPERITONEAL) FOR 6 HOURS. TBETA4 (1 MG/KG, INTRAPERITONEAL) WAS ADMINISTERED FOR 1 WEEK. WE DEMONSTRATED THAT TBETA4 PREVENTED ETHANOL- AND LPS-MEDIATED INCREASE IN LIVER INJURY MARKERS AS WELL AS CHANGES IN LIVER PATHOLOGY. IT ALSO PREVENTED ETHANOL- AND LPS-MEDIATED INCREASE IN OXIDATIVE STRESS BY DECREASING ROS AND LIPID PEROXIDATION AND INCREASING THE ANTIOXIDANTS, REDUCED GLUTATHIONE AND MANGANESE-DEPENDENT SUPEROXIDE DISMUTASE. IT ALSO PREVENTED THE ACTIVATION OF NUCLEAR FACTOR KAPPA B BY BLOCKING THE PHOSPHORYLATION OF THE INHIBITORY PROTEIN, IKAPPAB, THEREBY PREVENTED PROINFLAMMATORY CYTOKINE PRODUCTION. MOREOVER, TBETA4 PREVENTED FIBROGENESIS BY SUPPRESSING THE EPIGENETIC REPRESSOR, METHYL-CPG-BINDING PROTEIN 2, THAT COORDINATELY REVERSED THE EXPRESSION OF PEROXISOME PROLIFERATOR-ACTIVATED RECEPTOR-GAMMA AND DOWNREGULATED FIBROGENIC GENES, PLATELET-DERIVED GROWTH FACTOR-BETA RECEPTOR, ALPHA-SMOOTH MUSCLE ACTIN, COLLAGEN 1, AND FIBRONECTIN, RESULTING IN REDUCED FIBROSIS. OUR DATA SUGGEST THAT TBETA4 HAS ANTIOXIDANT, ANTI-INFLAMMATORY, AND ANTIFIBROTIC POTENTIAL DURING ALCOHOLIC LIVER INJURY. 2018 11 1036 30 CLASS I HISTONE DEACETYLASES REGULATE P53/NF-KAPPAB CROSSTALK IN CANCER CELLS. THE TRANSCRIPTION FACTORS NF-KAPPAB AND P53 AS WELL AS THEIR CROSSTALK DETERMINE THE FATE OF TUMOR CELLS UPON THERAPEUTIC INTERVENTIONS. REPLICATIVE STRESS AND CYTOKINES PROMOTE SIGNALING CASCADES THAT LEAD TO THE CO-REGULATION OF P53 AND NF-KAPPAB. CONSEQUENTLY, NUCLEAR P53/NF-KAPPAB SIGNALING COMPLEXES ACTIVATE NF-KAPPAB-DEPENDENT SURVIVAL GENES. THE 18 HISTONE DEACETYLASES (HDACS) ARE EPIGENETIC MODULATORS THAT FALL INTO FOUR CLASSES (I-IV). INHIBITORS OF HISTONE DEACETYLASES (HDACI) BECOME INCREASINGLY APPRECIATED AS ANTI-CANCER AGENTS. BASED ON THEIR EFFECTS ON P53 AND NF-KAPPAB, WE ADDRESSED WHETHER CLINICALLY RELEVANT HDACI AFFECT THE NF-KAPPAB/P53 CROSSTALK. THE CHEMOTHERAPEUTICS HYDROXYUREA, ETOPOSIDE, AND FLUDARABINE HALT CELL CYCLE PROGRESSION, INDUCE DNA DAMAGE, AND LEAD TO DNA FRAGMENTATION. THESE AGENTS CO-INDUCE P53 AND NF-KAPPAB-DEPENDENT GENE EXPRESSION IN CELL LINES FROM BREAST AND COLON CANCER AND IN PRIMARY CHRONIC LYMPHATIC LEUKEMIA (CLL) CELLS. USING SPECIFIC HDACI, WE FIND THAT THE CLASS I SUBGROUP OF HDACS, BUT NOT THE CLASS IIB DEACETYLASE HDAC6, ARE REQUIRED FOR THE HYDROXYUREA-INDUCED CROSSTALK BETWEEN P53 AND NF-KAPPAB. HDACI DECREASE THE BASAL AND STRESS-INDUCED EXPRESSION OF P53 AND BLOCK NF-KAPPAB-REGULATED GENE EXPRESSION. WE FURTHER SHOW THAT CLASS I HDACI INDUCE SENESCENCE IN PANCREATIC CANCER CELLS WITH MUTANT P53. 2017 12 4506 34 MRTF-A MEDIATES LPS-INDUCED PRO-INFLAMMATORY TRANSCRIPTION BY INTERACTING WITH THE COMPASS COMPLEX. CHRONIC INFLAMMATION UNDERSCORES THE PATHOGENESIS OF A RANGE OF HUMAN DISEASES. LIPOPOLYSACCHARIDE (LPS) ELICITS STRONG PRO-INFLAMMATORY RESPONSES IN MACROPHAGES THROUGH THE TRANSCRIPTION FACTOR NF-KAPPAB. THE EPIGENETIC MECHANISM UNDERLYING LPS-INDUCED PRO-INFLAMMATORY TRANSCRIPTION IS NOT FULLY UNDERSTOOD. HEREIN, WE DESCRIBE A ROLE FOR MYOCARDIN-RELATED TRANSCRIPTION FACTOR A (MRTF-A, ALSO KNOWN AS MKL1) IN THIS PROCESS. MRTF-A OVEREXPRESSION ENHANCED NF-KAPPAB-DEPENDENT PRO-INFLAMMATORY TRANSCRIPTION, WHEREAS MRTF-A SILENCING INHIBITED THIS PROCESS. MRTF-A DEFICIENCY ALSO REDUCED THE SYNTHESIS OF PRO-INFLAMMATORY MEDIATORS IN A MOUSE MODEL OF COLITIS. LPS PROMOTED THE RECRUITMENT OF MRTF-A TO THE PROMOTERS OF PRO-INFLAMMATORY GENES IN AN NF-KAPPAB-DEPENDENT MANNER. RECIPROCALLY, MRTF-A INFLUENCED THE NUCLEAR ENRICHMENT AND TARGET BINDING OF NF-KAPPAB. MECHANISTICALLY, MRTF-A WAS NECESSARY FOR THE ACCUMULATION OF ACTIVE HISTONE MODIFICATIONS ON NF-KAPPAB TARGET PROMOTERS BY COMMUNICATING WITH THE HISTONE H3K4 METHYLTRANSFERASE COMPLEX (COMPASS). SILENCING OF INDIVIDUAL MEMBERS OF COMPASS, INCLUDING ASH2, WDR5 AND SET1 (ALSO KNOWN AS SETD1A), DOWNREGULATED THE PRODUCTION OF PRO-INFLAMMATORY MEDIATORS AND IMPAIRED THE NF-KAPPAB KINETICS. IN SUMMARY, OUR WORK HAS UNCOVERED A PREVIOUSLY UNKNOWN FUNCTION FOR MRTF-A AND PROVIDED INSIGHTS INTO THE RATIONALIZED DEVELOPMENT OF ANTI-INFLAMMATORY THERAPEUTIC STRATEGIES. 2014 13 3832 38 INVOLVEMENT OF SPINAL SIRT1 IN DEVELOPMENT OF CHRONIC CONSTRICTION INJURY INDUCED NEUROPATHIC PAIN IN RATS. IT IS KNOWN THAT THE EPIGENETIC PROCESS OF HISTONE ACETYLATION IS INVOLVED IN THE NEUROPATHIC PAIN. THE AIM OF THIS STUDY WAS TO DETERMINE WHETHER SIRTUIN TYPE 1 (SIRT1), AN NAD(+) DEPENDENT DEACETYLASE, AFFECTED ALLODYNIA AND HYPERALGESIA IN NEUROPATHIC PAIN. THE NEUROPATHIC PAIN MODEL WAS ESTABLISHED BY LIGATURE OF THE RIGHT SCIATIC NERVE TO INDUCE CHRONIC CONSTRICTION INJURY (CCI) IN RATS. HISTONE ACETYLTRANSFERASE (HAT) ACTIVITY WAS INCREASED AND, AND HISTONE DEACETYLASE (HDAC) ACTIVITY WAS DECLINED IN TISSUE OF THE SPINAL DORSA HORN IN CCI RATES BY MEANS OF ENZYME-LINKED IMMUNOSORBENT ASSAY (ELISA). THE PERSISTENT HYPERALGESIA AND ALLODYNIA CAUSED BY CCI WERE ASSOCIATED WITH DOWNREGULATION OF SIRT1 AND UPREGULATION OF ACETYLATED-H3 (AC-H3) IN TISSUE OF THE SPINAL CORD BY WESTERN BLOT ASSAY, WHICH WAS REVERSED AFTER INTRATHECAL INJECTION OF SIRT1 AGONIST SRT1720. SRT1720 TREATMENT ACHIEVED ANALGESIC THROUGH INHIBITING THE ACETYLATION OF NUCLEAR FACTOR KAPPA B (NF-KAPPAB) AND BLOCKING THE RELEASES OF THE INFLAMMATORY FACTORS INCLUDING TUMOR NECROSIS FACTOR-ALPHA (TNF-ALPHA) AND INTERLEUKIN (IL)-6 BY MEANS OF WESTERN BLOT AND REAL-TIME QUANTITATIVE PCR (RT-PCR), RESPECTIVELY. TAKEN TOGETHER, THESE DATA SUGGEST THAT SIRT1 IN THE SPINAL CORD PLAYS AN IMPORTANT ROLE IN THE NEUROPATHIC PAIN IN THE RAT MODEL. 2018 14 3527 37 IL-6 ENHANCES THE NUCLEAR TRANSLOCATION OF DNA CYTOSINE-5-METHYLTRANSFERASE 1 (DNMT1) VIA PHOSPHORYLATION OF THE NUCLEAR LOCALIZATION SEQUENCE BY THE AKT KINASE. THE EPIGENETIC PROGRAMMING OF GENOMIC DNA IS ACCOMPLISHED, IN PART, BY SEVERAL DNA CYTOSINE-5-METHYLTRANSFERASES THAT ACT BY COVALENTLY MODIFYING CYTOSINES WITH THE ADDITION OF A METHYL GROUP. THIS COVALENT MODIFICATION IS MAINTAINED BY THE DNA CYTOSINE-5-METHYLTRANSFERASE-1 ENZYME (DNMT1), WHICH IS CAPABLE OF ACTING IN CONCERT WITH OTHER SIMILAR ENZYMES TO SILENCE IMPORTANT TUMOR SUPPRESSOR GENES. IL-6 IS A MULTIFUNCTIONAL MEDIATOR OF INFLAMMATION, ACTING THROUGH SEVERAL MAJOR SIGNALING CASCADES, INCLUDING THE PHOSPHATIDYLINOSITOL-3-KINASE PATHWAY (PI-3-K), WHICH ACTIVATES PROTEIN KINASE B (AKT/PKB) DOWNSTREAM. HERE, WE SHOW THAT THE SUBCELLULAR LOCALIZATION OF DNMT1 CAN BE ALTERED BY THE ADDITION OF IL-6, INCREASING THE RATE OF NUCLEAR TRANSLOCATION OF THE ENZYME FROM THE CYTOSOLIC COMPARTMENT. THE MECHANISM OF NUCLEAR TRANSLOCATION OF DNMT1 IS GREATLY ENHANCED BY PHOSPHORYLATION OF THE DNMT1 NUCLEAR LOCALIZATION SIGNAL (NLS) BY PKB/AKT KINASE. MUTAGENIC ALTERATION OF THE TWO AKT TARGET AMINO ACIDS WITHIN THE NLS RESULTS IN A MAJOR LOSS OF DNMT1 NUCLEAR TRANSLOCATION, WHILE THE CREATION OF A "PHOSPHO-MIMIC" AMINO ACID (MUTATION TO ACIDIC RESIDUES) RESTORES THIS COMPARTMENTATION ABILITY. THESE OBSERVATIONS SUGGEST AN INTERESTING HYPOTHESIS REGARDING HOW MEDIATORS OF CHRONIC INFLAMMATION MAY DISTURB THE DELICATE BALANCE OF CELLULAR COMPARTMENTALIZATION OF IMPORTANT PROTEINS, AND REVEALS A POTENTIAL MECHANISM FOR THE INDUCTION OR ENHANCEMENT OF TUMOR GROWTH VIA ALTERATION OF THE COMPONENTS INVOLVED IN THE EPIGENETIC PROGRAMMING OF A CELL. 2007 15 699 36 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 16 4836 26 ONCOGENIC FUNCTIONS OF THE TRANSCRIPTION FACTOR NRF2. NUCLEAR FACTOR E2-RELATED FACTOR 2 (NRF2) IS A TRANSCRIPTION FACTOR THAT CONTROLS THE EXPRESSION OF A LARGE POOL OF ANTIOXIDANT AND CYTOPROTECTIVE GENES REGULATING THE CELLULAR RESPONSE TO OXIDATIVE AND ELECTROPHILIC STRESS. NRF2 IS NEGATIVELY REGULATED BY KELCH-LIKE ECH-ASSOCIATED PROTEIN 1 (KEAP1) AND, UPON STIMULATION BY AN OXIDATIVE OR ELECTROPHILIC INSULT, IS RAPIDLY ACTIVATED BY PROTEIN STABILIZATION. OWING TO ITS CYTOPROTECTIVE FUNCTIONS, NRF2 HAS BEEN TRADITIONALLY STUDIED IN THE FIELD OF CHEMOPREVENTION; HOWEVER, THERE IS ACCUMULATED EVIDENCE THAT KEAP1/NRF2 MUTATIONS OR UNBALANCED REGULATION THAT LEADS TO OVEREXPRESSION OR HYPERACTIVATION OF NRF2 MAY PARTICIPATE IN TUMORIGENESIS AND BE INVOLVED IN CHEMORESISTANCE OF A WIDE NUMBER OF SOLID CANCERS AND LEUKEMIAS. IN ADDITION TO PROTECTING CELLS FROM REACTIVE OXYGEN SPECIES, NRF2 SEEMS TO PLAY A DIRECT ROLE IN CELL GROWTH CONTROL AND IS RELATED TO APOPTOSIS-REGULATING PATHWAYS. MOREOVER, NRF2 ACTIVITY IS CONNECTED WITH ONCOGENIC KINASE PATHWAYS, STRUCTURAL PROTEINS, HORMONAL REGULATION, OTHER TRANSCRIPTION FACTORS, AND EPIGENETIC ENZYMES INVOLVED IN THE PATHOGENESIS OF VARIOUS TYPES OF TUMORS. THE AIM OF THIS REVIEW IS TO COMPILE AND SUMMARIZE EXISTING KNOWLEDGE OF THE ONCOGENIC FUNCTIONS OF NRF2 TO PROVIDE A SOLID BASIS FOR ITS POTENTIAL USE AS A MOLECULAR MARKER AND PHARMACOLOGICAL TARGET IN CANCER. 2013 17 4582 33 N-TERMINAL BET BROMODOMAIN INHIBITORS DISRUPT A BRD4-P65 INTERACTION AND REDUCE INDUCIBLE NITRIC OXIDE SYNTHASE TRANSCRIPTION IN PANCREATIC BETA-CELLS. CHRONIC INFLAMMATION OF PANCREATIC ISLETS IS A KEY DRIVER OF BETA-CELL DAMAGE THAT CAN LEAD TO AUTOREACTIVITY AND THE EVENTUAL ONSET OF AUTOIMMUNE DIABETES (T1D). IN THE ISLET, ELEVATED LEVELS OF PROINFLAMMATORY CYTOKINES INDUCE THE TRANSCRIPTION OF THE INDUCIBLE NITRIC OXIDE SYNTHASE (INOS) GENE, NOS2, ULTIMATELY RESULTING IN INCREASED NITRIC OXIDE (NO). EXCESSIVE OR PROLONGED EXPOSURE TO NO CAUSES BETA-CELL DYSFUNCTION AND FAILURE ASSOCIATED WITH DEFECTS IN MITOCHONDRIAL RESPIRATION. RECENT STUDIES SHOWED THAT INHIBITION OF THE BROMODOMAIN AND EXTRATERMINAL DOMAIN (BET) FAMILY OF PROTEINS, A DRUGGABLE CLASS OF EPIGENETIC READER PROTEINS, PREVENTS THE ONSET AND PROGRESSION OF T1D IN THE NON-OBESE DIABETIC MOUSE MODEL. WE HYPOTHESIZED THAT BET PROTEINS CO-ACTIVATE TRANSCRIPTION OF CYTOKINE-INDUCED INFLAMMATORY GENE TARGETS IN BETA-CELLS AND THAT SELECTIVE, CHEMOTHERAPEUTIC INHIBITION OF BET BROMODOMAINS COULD REDUCE SUCH TRANSCRIPTION. HERE, WE INVESTIGATED THE ABILITY OF BET BROMODOMAIN SMALL MOLECULE INHIBITORS TO REDUCE THE BETA-CELL RESPONSE TO THE PROINFLAMMATORY CYTOKINE INTERLEUKIN 1 BETA (IL-1BETA). BET BROMODOMAIN INHIBITION ATTENUATED IL-1BETA-INDUCED TRANSCRIPTION OF THE INFLAMMATORY MEDIATOR NOS2 AND CONSEQUENT INOS PROTEIN AND NO PRODUCTION. REDUCED NOS2 TRANSCRIPTION IS CONSISTENT WITH INHIBITION OF NF-KAPPAB FACILITATED BY DISRUPTING THE INTERACTION OF A SINGLE BET FAMILY MEMBER, BRD4, WITH THE NF-KAPPAB SUBUNIT, P65. USING RECENTLY REPORTED SELECTIVE INHIBITORS OF THE FIRST AND SECOND BET BROMODOMAINS, INHIBITION OF ONLY THE FIRST BROMODOMAIN WAS NECESSARY TO REDUCE THE INTERACTION OF BRD4 WITH P65 IN BETA-CELLS. MOREOVER, INHIBITION OF THE FIRST BROMODOMAIN WAS SUFFICIENT TO MITIGATE IL-1BETA-DRIVEN DECREASES IN MITOCHONDRIAL OXYGEN CONSUMPTION RATES AND BETA-CELL VIABILITY. BY IDENTIFYING A ROLE FOR THE INTERACTION BETWEEN BRD4 AND P65 IN CONTROLLING THE RESPONSE OF BETA-CELLS TO PROINFLAMMATORY CYTOKINES, WE PROVIDE MECHANISTIC INFORMATION ON HOW BET BROMODOMAIN INHIBITION CAN DECREASE INFLAMMATION. THESE STUDIES ALSO SUPPORT THE POTENTIAL THERAPEUTIC APPLICATION OF MORE SELECTIVE BET BROMODOMAIN INHIBITORS IN ATTENUATING BETA-CELL INFLAMMATION. 2022 18 598 28 BETA-ADRENERGIC SIGNALING PROMOTES TUMOR ANGIOGENESIS AND PROSTATE CANCER PROGRESSION THROUGH HDAC2-MEDIATED SUPPRESSION OF THROMBOSPONDIN-1. CHRONIC BEHAVIORAL STRESS AND BETA-ADRENERGIC SIGNALING HAVE BEEN SHOWN TO PROMOTE CANCER PROGRESSION, WHOSE UNDERLYING MECHANISMS ARE LARGELY UNCLEAR, ESPECIALLY THE INVOLVEMENT OF EPIGENETIC REGULATION. HISTONE DEACETYLASE-2 (HDAC2), AN EPIGENETIC REGULATOR, IS CRITICAL FOR STRESS-INDUCED CARDIAC HYPERTROPHY. IT IS UNKNOWN WHETHER IT IS NECESSARY FOR BETA-ADRENERGIC SIGNALING-PROMOTED CANCER PROGRESSION. USING XENOGRAFT MODELS, WE SHOWED THAT CHRONIC BEHAVIORAL STRESS AND BETA-ADRENERGIC SIGNALING PROMOTE ANGIOGENESIS AND PROSTATE CANCER PROGRESSION. HDAC2 WAS INDUCED BY BETA-ADRENERGIC SIGNALING IN VITRO AND IN MOUSE XENOGRAFTS. WE NEXT UNCOVERED THAT HDAC2 IS A DIRECT TARGET OF CAMP RESPONSE ELEMENT-BINDING PROTEIN (CREB) THAT IS ACTIVATED BY BETA-ADRENERGIC SIGNALING. NOTABLY, HDAC2 IS NECESSARY FOR BETA-ADRENERGIC SIGNALING TO INDUCE ANGIOGENESIS. WE FURTHER DEMONSTRATED THAT, UPON CREB ACTIVATION, HDAC2 REPRESSES THROMBOSPONDIN-1 (TSP1), A POTENT ANGIOGENESIS INHIBITOR, THROUGH EPIGENETIC REGULATION. TOGETHER, THESE DATA ESTABLISH A NOVEL PATHWAY THAT HDAC2 AND TSP1 ACT DOWNSTREAM OF CREB ACTIVATION IN BETA-ADRENERGIC SIGNALING TO PROMOTE CANCER PROGRESSION. 2017 19 5301 27 PROTEIN PHOSPHATASE 2A CATALYTIC SUBUNIT ALPHA PLAYS A MYD88-DEPENDENT, CENTRAL ROLE IN THE GENE-SPECIFIC REGULATION OF ENDOTOXIN TOLERANCE. MYD88, THE INTRACELLULAR ADAPTOR OF MOST TLRS, MEDIATES EITHER PROINFLAMMATORY OR IMMUNOSUPPRESSIVE SIGNALING THAT CONTRIBUTES TO CHRONIC INFLAMMATION-ASSOCIATED DISEASES. ALTHOUGH GENE-SPECIFIC CHROMATIN MODIFICATIONS REGULATE INFLAMMATION, THE ROLE OF MYD88 SIGNALING IN ESTABLISHING SUCH EPIGENETIC LANDSCAPES UNDER DIFFERENT INFLAMMATORY STATES REMAINS ELUSIVE. USING QUANTITATIVE PROTEOMICS TO ENUMERATE THE INFLAMMATION-PHENOTYPIC CONSTITUENTS OF THE MYD88 INTERACTOME, WE FOUND THAT IN ENDOTOXIN-TOLERANT MACROPHAGES, PROTEIN PHOSPHATASE 2A CATALYTIC SUBUNIT ALPHA (PP2AC) ENHANCES ITS ASSOCIATION WITH MYD88 AND IS CONSTITUTIVELY ACTIVATED. KNOCKDOWN OF PP2AC PREVENTS SUPPRESSION OF PROINFLAMMATORY GENES AND RESISTANCE TO APOPTOSIS. THROUGH SITE-SPECIFIC DEPHOSPHORYLATION, CONSTITUTIVELY ACTIVE PP2AC DISRUPTS THE SIGNAL-PROMOTING TLR4-MYD88 COMPLEX AND BROADLY SUPPRESSES THE ACTIVITIES OF MULTIPLE PROINFLAMMATORY/PROAPOPTOTIC PATHWAYS AS WELL, SHIFTING PROINFLAMMATORY MYD88 SIGNALING TO A PROSURVIVAL MODE. CONSTITUTIVELY ACTIVE PP2AC TRANSLOCATED WITH MYD88 INTO THE NUCLEI OF TOLERANT MACROPHAGES ESTABLISHES THE IMMUNOSUPPRESSIVE PATTERN OF CHROMATIN MODIFICATIONS AND REPRESSES CHROMATIN REMODELING TO SELECTIVELY SILENCE PROINFLAMMATORY GENES, COORDINATING THE MYD88-DEPENDENT INFLAMMATION CONTROL AT BOTH SIGNALING AND EPIGENETIC LEVELS UNDER ENDOTOXIN-TOLERANT CONDITIONS. 2013 20 1158 38 CONTEXT-DEPENDENT EPIGENETIC REGULATION OF NUCLEAR FACTOR OF ACTIVATED T CELLS 1 IN PANCREATIC PLASTICITY. BACKGROUND & AIMS: THE ABILITY OF EXOCRINE PANCREATIC CELLS TO CHANGE THE CELLULAR PHENOTYPE IS REQUIRED FOR TISSUE REGENERATION UPON INJURY, BUT ALSO CONTRIBUTES TO THEIR MALIGNANT TRANSFORMATION AND TUMOR PROGRESSION. WE INVESTIGATED CONTEXT-DEPENDENT SIGNALING AND TRANSCRIPTION MECHANISMS THAT DETERMINE PANCREATIC CELL FATE DECISIONS TOWARD REGENERATION AND MALIGNANCY. IN PARTICULAR, WE STUDIED THE FUNCTION AND REGULATION OF THE INFLAMMATORY TRANSCRIPTION FACTOR NUCLEAR FACTOR OF ACTIVATED T CELLS 1 (NFATC1) IN PANCREATIC CELL PLASTICITY AND TISSUE ADAPTATION. METHODS: WE ANALYZED CELL PLASTICITY DURING PANCREATIC REGENERATION AND TRANSFORMATION IN MICE WITH PANCREAS-SPECIFIC EXPRESSION OF A CONSTITUTIVELY ACTIVE FORM OF NFATC1, OR DEPLETION OF ENHANCER OF ZESTE 2 HOMOLOGUE 2 (EZH2), IN THE CONTEXT OF WILD-TYPE OR CONSTITUTIVELY ACTIVATE KRAS, RESPECTIVELY. ACUTE AND CHRONIC PANCREATITIS WERE INDUCED BY INTRAPERITONEAL INJECTION OF CAERULEIN. EZH2-DEPENDENT REGULATION OF NFATC1 EXPRESSION WAS STUDIED IN MOUSE IN HUMAN PANCREATIC TISSUE AND CELLS BY IMMUNOHISTOCHEMISTRY, IMMUNOBLOTTING, AND QUANTITATIVE REVERSE TRANSCRIPTION POLYMERASE CHAIN REACTION. WE USED GENETIC AND PHARMACOLOGIC APPROACHES OF EZH2 AND NFATC1 INHIBITION TO STUDY THE CONSEQUENCES OF PATHWAY DISRUPTION ON PANCREATIC MORPHOLOGY AND FUNCTION. EPIGENETIC MODIFICATIONS ON THE NFATC1 GENE WERE INVESTIGATED BY CHROMATIN IMMUNOPRECIPITATION ASSAYS. RESULTS: NFATC1 WAS RAPIDLY AND TRANSIENTLY INDUCED IN EARLY ADAPTATION TO ACINAR CELL INJURY IN HUMAN SAMPLES AND IN MICE, WHERE IT PROMOTED ACINAR CELL TRANSDIFFERENTIATION AND BLOCKED PROLIFERATION OF METAPLASTIC PANCREATIC CELLS. HOWEVER, IN LATE STAGES OF REGENERATION, NFATC1 WAS EPIGENETICALLY SILENCED BY EZH2-DEPENDENT HISTONE METHYLATION, TO ENABLE ACINAR CELL REDIFFERENTIATION AND PREVENT ORGAN ATROPHY AND EXOCRINE INSUFFICIENCY. IN CONTRAST, ONCOGENIC ACTIVATION OF KRAS SIGNALING IN PANCREATIC DUCTAL ADENOCARCINOMA CELLS REVERSED THE EZH2-DEPENDENT EFFECTS ON THE NFATC1 GENE AND WAS REQUIRED FOR EZH2-MEDIATED TRANSCRIPTIONAL ACTIVATION OF NFATC1. CONCLUSIONS: IN STUDIES OF HUMAN AND MOUSE PANCREATIC CELLS AND TISSUE, WE IDENTIFIED CONTEXT-SPECIFIC EPIGENETIC REGULATION OF NFATC1 ACTIVITY AS AN IMPORTANT MECHANISM OF PANCREATIC CELL PLASTICITY. INHIBITORS OF EZH2 MIGHT THEREFORE INTERFERE WITH ONCOGENIC ACTIVITY OF NFATC1 AND BE USED IN TREATMENT OF PANCREATIC DUCTAL ADENOCARCINOMA. 2017