1 131 110 A2B ADENOSINE SIGNALING REPRESSES CIITA TRANSCRIPTION VIA AN EPIGENETIC MECHANISM IN VASCULAR SMOOTH MUSCLE CELLS. CHRONIC INFLAMMATION PLAYS A MAJOR ROLE IN THE PATHOGENESIS OF ATHEROSCLEROSIS. VASCULAR SMOOTH MUSCLE CELLS (VSMC), BY EXPRESSING AND PRESENTING MAJOR HISTOCOMPATIBILITY COMPLEX II (MHC II) MOLECULES, HELP RECRUIT T LYMPHOCYTE AND INITIATE THE INFLAMMATORY RESPONSE WITHIN THE VASCULATURE. WE HAVE PREVIOUSLY SHOWN THAT VSMCS ISOLATED FROM MICE WITH DEFICIENT ADENOSINE A2B RECEPTOR (A2B-NULL) EXHIBIT HIGHER EXPRESSION OF CLASS II TRANSACTIVATOR (CIITA), THE MASTER REGULATOR OF MHC II TRANSCRIPTION, COMPARED TO WILD TYPE LITTERMATES. HERE WE REPORT THAT ACTIVATION OF A2B ADENOSINE SIGNALING SUPPRESSES CIITA EXPRESSION IN HUMAN AORTIC SMOOTH MUSCLE CELLS. DOWN-REGULATION OF CIITA EXPRESSION WAS LARGELY ATTRIBUTABLE TO TRANSCRIPTIONAL REPRESSION OF TYPE III AND IV PROMOTERS. CHROMATIN IMMUNOPRECIPITATION (CHIP) ANALYSES REVEALED THAT A2B SIGNALING REPRESSED CIITA TRANSCRIPTION BY ATTENUATING SPECIFIC HISTONE MODIFICATIONS ON THE CIITA PROMOTERS IN A STAT1-DEPENDENT MANNER. STAT1 INTERACTED WITH PCAF/GCN5, HISTONE H3K9 ACETYLTRANSFERASES, AND WDR5, A KEY COMPONENT OF THE MAMMALIAN H3K4 METHYLTRANSFERASE COMPLEX, TO ACTIVATE CIITA TRANSCRIPTION. A2B SIGNALING PREVENTED RECRUITMENT OF PCAF/GCN5 AND WDR5 TO THE CIITA PROMOTERS IN A STAT1-DEPENDENT MANNER. IN CONCLUSION, OUR DATA SUGGEST THAT ADENOSINE A2B SIGNALING REPRESSES CIITA TRANSCRIPTION IN VSMCS BY MANIPULATING THE INTERACTION BETWEEN STAT1 AND THE EPIGENETIC MACHINERY. 2015 2 6294 29 THE PROINFLAMMATORY CYTOKINE TNFALPHA INDUCES DNA DEMETHYLATION-DEPENDENT AND -INDEPENDENT ACTIVATION OF INTERLEUKIN-32 EXPRESSION. IL-32 IS A CYTOKINE INVOLVED IN PROINFLAMMATORY IMMUNE RESPONSES TO BACTERIAL AND VIRAL INFECTIONS. HOWEVER, THE ROLE OF EPIGENETIC EVENTS IN THE REGULATION OF IL-32 GENE EXPRESSION IS UNDERSTUDIED. HERE WE SHOW THAT IL-32 IS REPRESSED BY DNA METHYLATION IN HEK293 CELLS. USING CHIP SEQUENCING, LOCUS-SPECIFIC METHYLATION ANALYSIS, CRISPR/CAS9-MEDIATED GENOME EDITING, AND RT-QPCR (QUANTITATIVE RT-PCR) AND IMMUNOBLOT ASSAYS, WE FOUND THAT SHORT-TERM TREATMENT (A FEW HOURS) WITH THE PROINFLAMMATORY CYTOKINE TUMOR NECROSIS FACTOR ALPHA (TNFALPHA) ACTIVATES IL-32 IN A DNA DEMETHYLATION-INDEPENDENT MANNER. IN CONTRAST, PROLONGED TNFALPHA TREATMENT (SEVERAL DAYS) INDUCED DNA DEMETHYLATION AT THE PROMOTER AND A CPG ISLAND IN THE IL-32 GENE IN A TET (TEN-ELEVEN TRANSLOCATION) FAMILY ENZYME- AND NF-KAPPAB-DEPENDENT MANNER. NOTABLY, THE HYPOMETHYLATION STATUS OF TRANSCRIPTIONAL REGULATORY ELEMENTS IN IL-32 WAS MAINTAINED FOR A LONG TIME (SEVERAL WEEKS), CAUSING ELEVATED IL-32 EXPRESSION EVEN IN THE ABSENCE OF TNFALPHA. CONSIDERING THAT IL-32 CAN, IN TURN, INDUCE TNFALPHA EXPRESSION, WE SPECULATE THAT SUCH FEEDFORWARD EVENTS MAY CONTRIBUTE TO THE TRANSITION FROM AN ACUTE INFLAMMATORY RESPONSE TO CHRONIC INFLAMMATION. 2019 3 1334 28 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 4 1966 27 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 5 3306 29 HIGH-PHOSPHATE-INDUCED CALCIFICATION IS RELATED TO SM22ALPHA PROMOTER METHYLATION IN VASCULAR SMOOTH MUSCLE CELLS. HYPERPHOSPHATEMIA IS CLOSELY RELATED TO VASCULAR CALCIFICATION IN PATIENTS WITH CHRONIC KIDNEY DISEASE. VASCULAR SMOOTH MUSCLE CELLS (VSMCS) EXPOSED TO HIGH PHOSPHATE CONCENTRATIONS IN VITRO UNDERGO PHENOTYPIC TRANSITION TO OSTEOBLAST-LIKE CELLS. MECHANISMS UNDERLYING THIS TRANSDIFFERENTIATION ARE NOT CLEAR. IN THIS STUDY WE USED TWO IN VITRO MODELS, HUMAN AORTIC SMOOTH MUSCLE CELLS AND RAT AORTIC RINGS, TO INVESTIGATE THE PHENOTYPIC TRANSITION OF VSMCS INDUCED BY HIGH PHOSPHATE. WE FOUND THAT HIGH PHOSPHATE CONCENTRATION (3.3 MMOL/L) IN THE MEDIUM WAS ASSOCIATED WITH INCREASED DNA METHYLTRANSFERASE ACTIVITY AND METHYLATION OF THE PROMOTER REGION OF SM22ALPHA. THIS WAS ACCOMPANIED BY LOSS OF THE SMOOTH MUSCLE CELL-SPECIFIC PROTEIN SM22ALPHA, GAIN OF THE OSTEOBLAST TRANSCRIPTION FACTOR CBFA1, AND INCREASED ALKALINE PHOSPHATASE ACTIVITY WITH THE SUBSEQUENT IN VITRO CALCIFICATION. THE ADDITION OF A DEMETHYLATING AGENT (PROCAINE) TO THE HIGH-PHOSPHATE MEDIUM REDUCED DNA METHYLTRANSFERASE ACTIVITY AND PREVENTED METHYLATION OF THE SM22ALPHA PROMOTER, WHICH WAS ACCOMPANIED BY AN INCREASE IN SM22ALPHA EXPRESSION AND LESS CALCIFICATION. ADDITIONALLY, DOWNREGULATION OF SM22ALPHA, EITHER BY SIRNA OR BY A METHYL GROUP DONOR (S-ADENOSYL METHIONINE), RESULTED IN OVEREXPRESSION OF CBFA1. IN CONCLUSION, WE DEMONSTRATE THAT METHYLATION OF SM22ALPHA PROMOTER IS AN IMPORTANT EVENT IN VASCULAR SMOOTH MUSCLE CELL CALCIFICATION AND THAT HIGH PHOSPHATE INDUCES THIS EPIGENETIC MODIFICATION. THESE FINDINGS UNCOVER A NEW INSIGHT INTO MECHANISMS BY WHICH HIGH PHOSPHATE CONCENTRATION PROMOTES VASCULAR CALCIFICATION. 2010 6 3526 42 IL-6 AND SIL-6R INDUCES STAT3-DEPENDENT DIFFERENTIATION OF HUMAN VSMCS INTO OSTEOBLAST-LIKE CELLS THROUGH JMJD2B-MEDIATED HISTONE DEMETHYLATION OF RUNX2. INFLAMMATION AND VASCULAR CALCIFICATION ARE INDEPENDENT RISK FACTORS OF CARDIOVASCULAR EVENTS. VASCULAR SMOOTH MUSCLE CELLS (VSMCS) EXHIBIT OSTEOBLAST-LIKE CHARACTERISTICS IN RESPONSE TO VARIOUS STIMULI SUCH AS OXIDIZED CHOLESTEROL AND INFLAMMATION. HOWEVER THE PRECISE MECHANISM OF TRANSCRIPTIONAL REGULATION OF VSMCS BY INFLAMMATORY STIMULI REMAINS UNCLEAR. WE INVESTIGATED THE PROCESS AND MECHANISMS OF INFLAMMATORY CYTOKINE-INDUCED TRANSFORMATION OF HUMAN VSMCS (HVSMCS) INTO OSTEOBLAST-LIKE CELLS, WITH A SPECIAL FOCUS ON EPIGENETIC CHANGES. OUR RESULTS DEMONSTRATED: (1) INTERLEUKIN-6 (IL-6)/SOLUBLE INTERLEUKIN-6 RECEPTOR (SIL-6R) INDUCED TRANSFORMATION OF HVSMCS INTO AN OSTEOBLAST PHENOTYPE, WITH SUBSEQUENT VASCULAR CALCIFICATION, BASED ON THE RESULTS OF ALIZARIN RED S STAINING AND O-CRESOLPHTHALEIN COMPLEXONE METHOD; (2) IL-6/SIL-6R ACCELERATED THE EXPRESSION OF RUNT-RELATED TRANSCRIPTION FACTOR 2 (RUNX2) BASED ON THE RESULTS OF QUANTITATIVE REAL-TIME POLYMERASE CHAIN REACTION; (3) KNOCKDOWN OF SIGNAL TRANSDUCER AND ACTIVATOR OF TRANSCRIPTION (STAT) 3 REDUCED IL-6/SIL-6R-INDUCED RUNX2 MRNA EXPRESSION AND OSTEOBLAST TRANSDIFFERENTIATION OF HVSMCS; (4) CHROMATIN IMMUNOPRECIPITATION (CHIP) COUPLED WITH PCR (CHIP-PCR) IDENTIFIED A STAT-BINDING SITE IN RUNX2 PROMOTER REGION CONTAINING TRIMETHYLATED HISTONE 3 LYSINE 9 (H3K9ME3), A TRANSCRIPTIONAL REPRESSOR, AND H3K4ME3, A TRANSCRIPTIONAL ENHANCER. STIMULATION WITH IL-6/SIL-6R SUPPRESSED H3K9ME3 BUT NOT H3K4ME3 THROUGH THE RECRUITMENT OF JUMONJI DOMAIN-CONTAINING PROTEIN (JMJD) 2B, A HISTONE LYSINE DEMETHYLASE, AT THE STAT-BINDING SITE IN RUNX2 PROMOTER REGION; (5) IL-6/SIL-6R-INDUCED RUNX2 GENE EXPRESSION WAS INHIBITED IN HVSMCS PRETREATED WITH JIB04, JMJD2 INHIBITOR, AND THE INHIBITORY EFFECT WAS JIB04 DOSE-DEPENDENT. OUR RESULTS INDICATE THAT THE IL-6/STAT3/JMJD2B PATHWAY REGULATES HVSMCS DIFFERENTIATION INTO OSTEOBLAST-LIKE CELLS, WHICH SUGGEST ITS PATHOGENIC ROLE IN VASCULAR CALCIFICATION ASSOCIATED WITH CHRONIC INFLAMMATION. 2019 7 26 24 A 6-ALKYLSALICYLATE HISTONE ACETYLTRANSFERASE INHIBITOR INHIBITS HISTONE ACETYLATION AND PRO-INFLAMMATORY GENE EXPRESSION IN MURINE PRECISION-CUT LUNG SLICES. LYSINE ACETYLATIONS ARE POST-TRANSLATIONAL MODIFICATIONS OF CELLULAR PROTEINS, THAT ARE CRUCIAL IN THE REGULATION OF MANY CELLULAR PROCESSES. LYSINE ACETYLATIONS ON HISTONE PROTEINS ARE PART OF THE EPIGENETIC CODE REGULATING GENE EXPRESSION AND ARE INSTALLED BY HISTONE ACETYLTRANSFERASES. OBSERVATIONS THAT INFLAMMATORY LUNG DISEASES, SUCH AS ASTHMA AND CHRONIC OBSTRUCTIVE PULMONARY DISEASE, ARE CHARACTERIZED BY INCREASED HISTONE ACETYLTRANSFERASE ACTIVITY INDICATE THAT DEVELOPMENT OF SMALL MOLECULE INHIBITORS FOR THESE ENZYMES MIGHT BE A VALUABLE APPROACH TOWARDS NEW THERAPIES FOR THESE DISEASES. THE 6-ALKYLSALICYLATE MG149 IS A CANDIDATE TO EXPLORE THIS HYPOTHESIS BECAUSE IT HAS BEEN DEMONSTRATED TO INHIBIT THE MYST TYPE HISTONE ACETYLTRANSFERASES. IN THIS STUDY, WE DETERMINED THE K(I) VALUE FOR INHIBITION OF THE MYST TYPE HISTONE ACETYLTRANSFERASE KAT8 BY MG149 TO BE 39 +/- 7.7 MUM. UPON INVESTIGATING WHETHER THE INHIBITION OF HISTONE ACETYLTRANSFERASES BY MG149 CORRELATES WITH INHIBITION OF HISTONE ACETYLATION IN MURINE PRECISION-CUT LUNG SLICES, INHIBITION OF ACETYLATION WAS OBSERVED USING AN LC-MS/MS BASED ASSAY ON HISTONE H4 RES 4-17, WHICH CONTAINS THE TARGET LYSINE OF KAT8. FOLLOWING UP ON THIS, UPON TREATMENT WITH MG149, REDUCED PRO-INFLAMMATORY GENE EXPRESSION WAS OBSERVED IN LIPOPOLYSACCHARIDE AND INTERFERON GAMMA STIMULATED MURINE PRECISION-CUT LUNG SLICES. BASED ON THIS, WE PROPOSE THAT 6-ALKYLSALICYLATES SUCH AS MG149 HAVE POTENTIAL FOR DEVELOPMENT TOWARDS APPLICATIONS IN THE TREATMENT OF INFLAMMATORY LUNG DISEASES. 2017 8 4696 32 NF-KAPPAB REPRESSES RETINOIC ACID RECEPTOR-MEDIATED GPRC5A TRANSACTIVATION IN LUNG EPITHELIAL CELLS TO PROMOTE NEOPLASIA. CHRONIC INFLAMMATION IS ASSOCIATED WITH LUNG TUMORIGENESIS, IN WHICH NF-KAPPAB-MEDIATED EPIGENETIC REGULATION PLAYS A CRITICAL ROLE. LUNG TUMOR SUPPRESSOR G PROTEIN-COUPLED RECEPTOR, FAMILY C, MEMBER 5A (GPRC5A), IS REPRESSED IN MOST NON-SMALL CELL LUNG CANCER (NSCLC); HOWEVER, THE MECHANISMS REMAIN UNCLEAR. HERE, WE SHOW THAT NF-KAPPAB ACTS AS A TRANSCRIPTIONAL REPRESSOR IN SUPPRESSION OF GPRC5A. NF-KAPPAB INDUCED GPRC5A REPRESSION BOTH IN VITRO AND IN VIVO. INTRIGUINGLY, TRANSACTIVATION OF NF-KAPPAB DOWNSTREAM TARGETS WAS NOT REQUIRED, BUT THE TRANSACTIVATION DOMAIN OF RELA/P65 WAS REQUIRED FOR GPRC5A REPRESSION. NF-KAPPAB DID NOT BIND TO ANY POTENTIAL CIS-ELEMENT IN THE GPRC5A PROMOTER. INSTEAD, P65 WAS COMPLEXED WITH RETINOIC ACID RECEPTOR ALPHA/BETA (RARALPHA/BETA) AND RECRUITED TO THE RA RESPONSE ELEMENT SITE AT THE GPRC5A PROMOTER, RESULTING IN DISRUPTED RNA POLYMERASE II COMPLEXING AND SUPPRESSED TRANSCRIPTION. NOTABLY, PHOSPHORYLATION ON SERINE 276 OF P65 WAS REQUIRED FOR INTERACTION WITH RARALPHA/BETA AND REPRESSION OF GPRC5A. MOREOVER, NF-KAPPAB-MEDIATED EPIGENETIC REPRESSION WAS THROUGH SUPPRESSION OF ACETYLATED HISTONE H3K9 (H3K9AC), BUT NOT DNA METHYLATION OF THE CPG ISLANDS, AT THE GPRC5A PROMOTER. CONSISTENTLY, A HISTONE DEACETYLASE INHIBITOR, BUT NOT DNA METHYLATION INHIBITOR, RESTORED GPRC5A EXPRESSION IN NSCLC CELLS. THUS, NF-KAPPAB INDUCES TRANSCRIPTIONAL REPRESSION OF GPRC5A VIA A COMPLEX WITH RARALPHA/BETA AND MEDIATES EPIGENETIC REPRESSION VIA SUPPRESSION OF H3K9AC. 2023 9 984 31 CHRONIC PSYCHOLOGICAL STRESS ALTERS GENE EXPRESSION IN RAT COLON EPITHELIAL CELLS PROMOTING CHROMATIN REMODELING, BARRIER DYSFUNCTION AND INFLAMMATION. CHRONIC STRESS IS COMMONLY ASSOCIATED WITH ENHANCED ABDOMINAL PAIN (VISCERAL HYPERSENSITIVITY), BUT THE CELLULAR MECHANISMS UNDERLYING HOW CHRONIC STRESS INDUCES VISCERAL HYPERSENSITIVITY ARE POORLY UNDERSTOOD. IN THIS STUDY, WE EXAMINED CHANGES IN GENE EXPRESSION IN COLON EPITHELIAL CELLS FROM A RAT MODEL USING RNA-SEQUENCING TO EXAMINE STRESS-INDUCED CHANGES TO THE TRANSCRIPTOME. FOLLOWING CHRONIC STRESS, THE MOST SIGNIFICANTLY UP-REGULATED GENES INCLUDED ATG16L1, COQ10B, DCAF13, NAT2, PTBP2, RRAS2, SPINK4 AND DOWN-REGULATED GENES INCLUDING ABAT, CITED2, CNNM2, DAB2IP, PLEKHM1, SCD2, AND TAB2. THE PRIMARY ALTERED BIOLOGICAL PROCESSES REVEALED BY NETWORK ENRICHMENT ANALYSIS WERE INFLAMMATION/IMMUNE RESPONSE, TISSUE MORPHOGENESIS AND DEVELOPMENT, AND NUCLEOSOME/CHROMATIN ASSEMBLY. THE MOST SIGNIFICANTLY DOWN-REGULATED PROCESS WAS THE DIGESTIVE SYSTEM DEVELOPMENT/FUNCTION, WHEREAS THE MOST SIGNIFICANTLY UP-REGULATED PROCESSES WERE INFLAMMATORY RESPONSE, ORGANISMAL INJURY, AND CHROMATIN REMODELING MEDIATED BY H3K9 METHYLATION. FURTHERMORE, A SUBPOPULATION OF STRESSED RATS DEMONSTRATED VERY SIGNIFICANTLY ALTERED GENE EXPRESSION AND TRANSCRIPT ISOFORMS, ENRICHED FOR THE DIFFERENTIAL EXPRESSION OF GENES INVOLVED IN THE INFLAMMATORY RESPONSE, INCLUDING UPREGULATION OF CYTOKINE AND CHEMOKINE RECEPTOR GENE EXPRESSION COUPLED WITH DOWNREGULATION OF EPITHELIAL ADHERENS AND TIGHT JUNCTION MRNAS. IN SUMMARY, THESE FINDINGS SUPPORT THAT CHRONIC STRESS IS ASSOCIATED WITH INCREASED LEVELS OF CYTOKINES AND CHEMOKINES, THEIR DOWNSTREAM SIGNALING PATHWAYS COUPLED TO DYSREGULATION OF INTESTINAL CELL DEVELOPMENT AND FUNCTION. EPIGENETIC REGULATION OF CHROMATIN REMODELING LIKELY PLAYS A PROMINENT ROLE IN THIS PROCESS. RESULTS ALSO SUGGEST THAT SUPER ENHANCERS PLAY A PRIMARY ROLE IN CHRONIC STRESS-ASSOCIATED INTESTINAL BARRIER DYSFUNCTION. 2022 10 5101 25 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 11 1293 26 DECREASED ERK AND JNK SIGNALING CONTRIBUTE TO GENE OVEREXPRESSION IN "SENESCENT" CD4+CD28- T CELLS THROUGH EPIGENETIC MECHANISMS. AN INFLAMMATORY AND CYTOTOXIC CD4+CD28- T CELL SUBSET INFILTRATES ATHEROSCLEROTIC PLAQUES AND IS IMPLICATED IN PLAQUE RUPTURE AND MYOCARDIAL INFARCTIONS. THIS PATHOLOGIC SUBSET DEVELOPS WITH REPLICATIVE STRESS AND IS FOUND IN PATIENTS WITH CHRONIC INFLAMMATORY DISEASES SUCH AS RA AS WELL AS WITH AGING. CD4+CD28- CELLS OVEREXPRESS GENES NORMALLY SUPPRESSED BY DNA METHYLATION IN CD4+CD28+ T CELLS, SUCH AS KIR, PERFORIN, AND CD70. HOW THIS SUBSET OVER EXPRESSES METHYLATION-SENSITIVE GENES IS UNKNOWN. DNA METHYLATION PATTERNS ARE MAINTAINED IN PROLIFERATING CELLS BY DNMTS, WHICH ARE UP-REGULATED DURING MITOSIS BY THE ERK AND JNK SIGNALING PATHWAYS. WE HYPOTHESIZED THAT DEFECTS IN THESE SIGNALING PATHWAYS CONTRIBUTE TO ALTERED GENE EXPRESSION IN HUMAN CD4+CD28- CELLS THROUGH EFFECTS ON DNA METHYLATION. WE REPORT THAT SIGNALING THROUGH THE ERK AND JNK PATHWAYS IS DECREASED IN CD4+CD28- RELATIVE TO CD4+CD28+ CELLS FROM THE SAME INDIVIDUALS AND THAT ERK AND JNK PATHWAY INHIBITION DECREASES DNMT1 AND -3A LEVELS, WHICH IN TURN, CAUSES DEMETHYLATION AND OVEREXPRESSION OF THE TNFSF7 (CD70) GENE. WE ALSO REPORT THAT CD4+CD28- T CELLS OVEREXPRESS PP5, A STRESS-INDUCED INHIBITOR OF THE ERK AND JNK SIGNALING PATHWAYS THAT MAY CONTRIBUTE TO THE SIGNALING DEFECTS. WE CONCLUDE THAT DECREASED ERK AND JNK SIGNALING IN THE CD4+CD28- SUBSET, ARISING WITH REPLICATIVE STRESS, CAN LEAD TO THE OVEREXPRESSION OF NORMALLY SUPPRESSED GENES THROUGH EFFECTS ON DNMTS AND CONSEQUENTLY, CHROMATIN STRUCTURE. 2010 12 2432 27 EPIGENETIC SILENCING OF MIR-708 ENHANCES NF-KAPPAB SIGNALING IN CHRONIC LYMPHOCYTIC LEUKEMIA. MICRORNAS (MIRNAS) ARE POST-TRANSCRIPTIONAL REGULATORS OF GENE EXPRESSION AND THEIR DEREGULATION IS INVOLVED IN TUMOR DEVELOPMENT. EPIGENETIC GENE SILENCING IN CANCER BY DNA METHYLATION CONTRIBUTES TO THE SILENCING OF TUMOR-SUPPRESSOR GENES, INCLUDING MIRNAS. WE HAVE RECENTLY SHOWN THAT THE PROMOTER OF MIR-708 IS ABERRANTLY METHYLATED IN CHRONIC LYMPHOCYTIC LEUKEMIA (CLL). TO CHARACTERIZE THE MOLECULAR SIGNALING NETWORKS THAT ARE INFLUENCED BY MIR-708, WE PERFORMED A LUCIFERASE-BASED SCREEN EVALUATING THE EFFECTS OF ECTOPIC MIR-708 EXPRESSION ON LEUKEMIA-RELEVANT SIGNALING PATHWAYS. WE FOUND THAT MIR-708 STRONGLY REPRESSED NF-KAPPAB SIGNALING, A PATHWAY KNOWN TO BE DEREGULATED IN CLL. AMONG THE PREDICTED MIR-708 TARGETS WAS IKKBETA (INHIBITOR OF KAPPA LIGHT POLYPEPTIDE GENE ENHANCER IN B CELLS, KINASE-BETA/IKBKB), A KEY KINASE FACILITATING NF-KAPPAB SIGNALING. WE VALIDATED THE INTERACTION OF MIR-708 WITH THE 3'-UNTRANSLATED REGION OF IKKBETA AND FOUND THAT MIR-708 OVEREXPRESSION REPRESSES ENDOGENOUS IKKBETA. PHOSPHORYLATION OF THE IKKBETA TARGET IKAPPABALPHA AND EXPRESSION OF KNOWN NF-KAPPAB TARGET GENES WERE IMPAIRED BY MIR-708. FURTHERMORE, WE IDENTIFIED AN ENHANCER REGION DOWNSTREAM OF THE MIR-708 PROMOTER THAT DISPLAYS A DISTINCT DNA METHYLATION STATUS IN CLL. HIGH ENHANCER METHYLATION IS SIGNIFICANTLY CORRELATED WITH LOWER MIR-708 EXPRESSION AND IS PREDOMINANTLY FOUND IN PATIENTS WITH POOR PROGNOSIS AND SHORTER TIME TO TREATMENT. THESE RESULTS DEMONSTRATE THAT MIR-708 REGULATES THE NF-KAPPAB PATHWAY BY TARGETING IKKBETA, AND THAT METHYLATION OF A KEY ENHANCER REGION CONTRIBUTES TO ITS SUPPRESSION IN CLL. 2015 13 3128 34 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 14 1461 32 DISRUPTION OF RCAN1.4 EXPRESSION MEDIATED BY YY1/HDAC2 MODULATES CHRONIC RENAL ALLOGRAFT INTERSTITIAL FIBROSIS. CHRONIC ALLOGRAFT DYSFUNCTION (CAD) IS A MAJOR FACTOR THAT HINDERS KIDNEY TRANSPLANT SURVIVAL IN THE LONG RUN. EPITHELIAL-MESENCHYMAL TRANSITION (EMT) HAS BEEN CONFIRMED TO SIGNIFICANTLY CONTRIBUTE TO INTERSTITIAL FIBROSIS/TUBULAR ATROPHY (IF/TA), WHICH IS THE MAIN HISTOPATHOLOGICAL FEATURE OF CAD. ABERRANT EXPRESSION OF THE REGULATOR OF CALCINEURIN 1 (RCAN1), RECOGNIZED AS AN ENDOGENOUS INHIBITOR OF THE CALCINEURIN PHOSPHATASE, HAS BEEN SHOWN TO BE EXTENSIVELY INVOLVED IN VARIOUS KIDNEY DISEASES. HOWEVER, IT REMAINS UNCLEAR HOW RCAN1.4 REGULATES IF/TA FORMATION IN CAD PATIENTS. HEREIN, AN IN VIVO MOUSE RENAL TRANSPLANTATION MODEL AND AN IN VITRO MODEL OF HUMAN RENAL TUBULAR EPITHELIAL CELLS (HK-2) TREATED WITH TUMOR NECROSIS FACTOR-ALPHA (TNF-ALPHA) WERE EMPLOYED. OUR RESULTS PROVED THAT RCAN1.4 EXPRESSION WAS DECREASED IN VIVO AND IN VITRO, IN ADDITION TO THE UP-REGULATION OF YIN YANG 1 (YY1), A TRANSCRIPTION FACTOR THAT HAS BEEN REPORTED TO CONVEY MULTIPLE FUNCTIONS IN CHRONIC KIDNEY DISEASE (CKD). KNOCKING IN OF RCAN1.4 EFFICIENTLY ATTENUATED CHRONIC RENAL ALLOGRAFT INTERSTITIAL FIBROSIS IN VIVO AND INHIBITED TNF-ALPHA-INDUCED EMT IN VITRO THROUGH REGULATING ANTI-OXIDATIVE STRESS AND THE CALCINEURIN/NUCLEAR FACTOR OF ACTIVATED T CELLS CYTOPLASMIC 1 (NFATC1) SIGNALING PATHWAY. IN ADDITION, SUPPRESSION OF YY1 MEDIATED BY SHRNA OR SIRNA ALLEVIATED TNF-ALPHA-INDUCED EMT THROUGH ABOLISHING REACTIVE SPECIES PARTLY IN AN RCAN1.4-DEPENDENT MANNER. NOTABLY, WE CONFIRMED THAT YY1 NEGATIVELY REGULATED RCAN1.4 TRANSCRIPTION BY DIRECTLY INTERACTING WITH THE RCAN1.4 PROMOTER. IN ADDITION, HISTONE DEACETYLASE 2 (HDAC2) INTERACTED WITH YY1 TO FORM A MULTI-MOLECULAR COMPLEX, WHICH WAS INVOLVED IN TNF-ALPHA-INDUCED RCAN1.4 TRANSCRIPTIONAL REPRESSION. THEREFORE, RCAN1.4 IS SUGGESTED TO BE MODULATED BY THE YY1/HDAC2 TRANSCRIPTION REPRESSOR COMPLEX IN AN EPIGENETIC MANNER, WHICH IS A MEDIATED NEPHROPROTECTIVE EFFECT PARTLY THROUGH MODULATING O2?- GENERATION AND THE CALCINEURIN/NFATC1 SIGNALING PATHWAY. THUS, THE YY1-RCAN1.4 AXIS CONSTITUTES AN INNOVATIVE TARGET FOR IF/TA TREATMENT IN CAD PATIENTS. 2023 15 662 32 BLOOD MONOCYTE TRANSCRIPTOME AND EPIGENOME ANALYSES REVEAL LOCI ASSOCIATED WITH HUMAN ATHEROSCLEROSIS. LITTLE IS KNOWN REGARDING THE EPIGENETIC BASIS OF ATHEROSCLEROSIS. HERE WE PRESENT THE CD14+ BLOOD MONOCYTE TRANSCRIPTOME AND EPIGENOME SIGNATURES ASSOCIATED WITH HUMAN ATHEROSCLEROSIS. THE TRANSCRIPTOME SIGNATURE INCLUDES TRANSCRIPTION COACTIVATOR, ARID5B, WHICH IS KNOWN TO FORM A CHROMATIN DEREPRESSOR COMPLEX WITH A HISTONE H3K9ME2-SPECIFIC DEMETHYLASE AND PROMOTE ADIPOGENESIS AND SMOOTH MUSCLE DEVELOPMENT. ARID5B CPG (CG25953130) METHYLATION IS INVERSELY ASSOCIATED WITH BOTH ARID5B EXPRESSION AND ATHEROSCLEROSIS, CONSISTENT WITH THIS CPG RESIDING IN AN ARID5B ENHANCER REGION, BASED ON CHROMATIN CAPTURE AND HISTONE MARKS DATA. MEDIATION ANALYSIS SUPPORTS ASSUMPTIONS THAT ARID5B EXPRESSION MEDIATES EFFECTS OF CG25953130 METHYLATION AND SEVERAL CARDIOVASCULAR DISEASE RISK FACTORS ON ATHEROSCLEROTIC BURDEN. IN LIPOPOLYSACCHARIDE-STIMULATED HUMAN THP1 MONOCYTES, ARID5B KNOCKDOWN REDUCED EXPRESSION OF GENES INVOLVED IN ATHEROSCLEROSIS-RELATED INFLAMMATORY AND LIPID METABOLISM PATHWAYS, AND INHIBITED CELL MIGRATION AND PHAGOCYTOSIS. THESE DATA SUGGEST THAT ARID5B EXPRESSION, POSSIBLY REGULATED BY AN EPIGENETICALLY CONTROLLED ENHANCER, PROMOTES ATHEROSCLEROSIS BY DYSREGULATING IMMUNOMETABOLISM TOWARDS A CHRONIC INFLAMMATORY PHENOTYPE.THE MOLECULAR MECHANISMS MEDIATING THE IMPACT OF ENVIRONMENTAL FACTORS IN ATHEROSCLEROSIS ARE UNCLEAR. HERE, THE AUTHORS EXAMINE CD14+ BLOOD MONOCYTE'S TRANSCRIPTOME AND EPIGENOME SIGNATURES TO FIND DIFFERENTIAL METHYLATION AND EXPRESSION OF ARID5B TO BE ASSOCIATED WITH HUMAN ATHEROSCLEROSIS. 2017 16 164 32 ABNORMAL HISTONE METHYLATION IS RESPONSIBLE FOR INCREASED VASCULAR ENDOTHELIAL GROWTH FACTOR 165A SECRETION FROM AIRWAY SMOOTH MUSCLE CELLS IN ASTHMA. VASCULAR ENDOTHELIAL GROWTH FACTOR (VEGF), A KEY ANGIOGENIC MOLECULE, IS ABERRANTLY EXPRESSED IN SEVERAL DISEASES INCLUDING ASTHMA WHERE IT CONTRIBUTES TO BRONCHIAL VASCULAR REMODELING AND CHRONIC INFLAMMATION. ASTHMATIC HUMAN AIRWAY SMOOTH MUSCLE CELLS HYPERSECRETE VEGF, BUT THE MECHANISM IS UNCLEAR. IN THIS STUDY, WE DEFINED THE MECHANISM IN HUMAN AIRWAY SMOOTH MUSCLE CELLS FROM NONASTHMATIC AND ASTHMATIC PATIENTS. WE FOUND THAT ASTHMATIC CELLS LACKED A REPRESSION COMPLEX AT THE VEGF PROMOTER, WHICH WAS PRESENT IN NONASTHMATIC CELLS. RECRUITMENT OF G9A, TRIMETHYLATION OF HISTONE H3 AT LYSINE 9 (H3K9ME3), AND A RESULTANT DECREASE IN RNA POLYMERASE II AT THE VEGF PROMOTER WAS CRITICAL TO REPRESSION OF VEGF SECRETION IN NONASTHMATIC CELLS. AT THE ASTHMATIC PROMOTER, H3K9ME3 WAS ABSENT BECAUSE OF FAILED RECRUITMENT OF G9A; RNA POLYMERASE II BINDING, IN ASSOCIATION WITH TATA-BINDING PROTEIN-ASSOCIATED FACTOR 1, WAS INCREASED; H3K4ME3 WAS PRESENT; AND SP1 BINDING WAS EXAGGERATED AND SUSTAINED. IN CONTRAST, DNA METHYLATION AND HISTONE ACETYLATION WERE SIMILAR IN ASTHMATIC AND NONASTHMATIC CELLS. THIS IS THE FIRST STUDY, TO OUR KNOWLEDGE, TO SHOW THAT AIRWAY CELLS IN ASTHMA HAVE ALTERED EPIGENETIC REGULATION OF REMODELING GENE(S). HISTONE METHYLATION AT GENES SUCH AS VEGF MAY BE AN IMPORTANT NEW THERAPEUTIC TARGET. 2012 17 6077 31 THE EFFECT OF CD4 RECEPTOR DOWNREGULATION AND ITS DOWNSTREAM SIGNALING MOLECULES ON HIV-1 LATENCY. HIV-1 CAN ESTABLISH A LATENT INFECTION IN MEMORY CD4+T CELLS TO EVADE THE HOST IMMUNE RESPONSE. CD4 MOLECULES CAN ACT NOT ONLY AS THE HIV-1 RECEPTOR FOR ENTRY BUT ALSO AS THE TRIGGER IN AN INTRACELLULAR SIGNALING CASCADE FOR T-CELL ACTIVATION AND PROLIFERATION VIA PROTEIN TYROSINE KINASES. NOVEL CHRONIC HIV-1-INFECTED A3.01-DERIVED (NCHA) CELLS WERE USED TO EXAMINE THE INVOLVEMENT OF CD4 DOWNSTREAM SIGNALING IN HIV-1 LATENCY. CD4 RECEPTORS IN NCHA CELLS WERE DRAMATICALLY DOWNREGULATED ON ITS SURFACE BUT WERE SLIGHTLY DECREASED IN WHOLE-CELL LYSATES. THE EXPRESSION LEVELS OF CD4 DOWNSTREAM SIGNALING MOLECULES, INCLUDING P56(LCK), ZAP-70, LAT, AND C-JUN, WERE SHARPLY DECREASED IN NCHA CELLS. THE LOWERED HISTONE MODIFICATIONS OF H3K4ME3 AND H3K9AC CORRELATED WITH THE DOWNREGULATION OF P56(LCK), ZAP-70, AND LAT IN NCHA CELLS. AP-1 BINDING ACTIVITY WAS ALSO REDUCED IN NCHA CELLS. LAT AND C-JUN SUPPRESSED IN NCHA CELLS WERE HIGHLY INDUCED AFTER PMA TREATMENT. IN EPIGENETIC ANALYSIS, OTHER SIGNAL TRANSDUCTION MOLECULES WHICH ARE ASSOCIATED WITH ACTIVE AND/OR LATENT HIV-1 INFECTION SHOWED NORMAL STATES IN HIV-1 LATENTLY INFECTED CELLS COMPARED TO A3.01 CELLS. IN CONCLUSION, WE DEMONSTRATED THAT THE HIV-1 LATENT STATE IS SUSTAINED BY THE REDUCTION OF DOWNSTREAM SIGNALING MOLECULES VIA THE DOWNREGULATION OF CD4 AND THE ATTENUATED ACTIVITY OF TRANSCRIPTION FACTOR AS AP-1. THE HIV-1 LATENCY MODEL VIA T-CELL DEACTIVATION MAY PROVIDE SOME CLUES FOR THE DEVELOPMENT OF THE NEW ANTIRESERVOIR THERAPY. 2011 18 2068 35 EPIGENETIC CONTROL OF MICROSOMAL PROSTAGLANDIN E SYNTHASE-1 BY HDAC-MEDIATED RECRUITMENT OF P300. NONSTEROIDAL ANTI-INFLAMMATORY DRUGS ARE THE MOST WIDELY USED MEDICINE TO TREAT PAIN AND INFLAMMATION, AND TO INHIBIT PLATELET FUNCTION. UNDERSTANDING THE EXPRESSION REGULATION OF ENZYMES OF THE PROSTANOID PATHWAY IS OF GREAT MEDICAL RELEVANCE. HISTONE ACETYLATION CRUCIALLY CONTROLS GENE EXPRESSION. WE SET OUT TO IDENTIFY THE IMPACT OF HISTONE DEACETYLASES (HDACS) ON THE GENERATION OF PROSTANOIDS AND EXAMINE THE CONSEQUENCES ON VASCULAR FUNCTION. HDAC INHIBITION (HDACI) WITH THE PAN-HDAC INHIBITOR, VORINOSTAT, ATTENUATED PROSTAGLANDIN (PG)E(2) GENERATION IN THE MURINE VASCULATURE AND IN HUMAN VASCULAR SMOOTH MUSCLE CELLS. IN LINE WITH THIS, THE EXPRESSION OF THE KEY ENZYME FOR PGE(2) SYNTHESIS, MICROSOMAL PGE SYNTHASE-1 (PTGES1), WAS REDUCED BY HDACI. ACCORDINGLY, THE RELAXATION TO ARACHIDONIC ACID WAS DECREASED AFTER EX VIVO INCUBATION OF MURINE VESSELS WITH HDACI. TO IDENTIFY THE UNDERLYING MECHANISM, CHROMATIN IMMUNOPRECIPITATION (CHIP) AND CHIP-SEQUENCING ANALYSIS WERE PERFORMED. THESE RESULTS SUGGEST THAT HDACS ARE INVOLVED IN THE RECRUITMENT OF THE TRANSCRIPTIONAL ACTIVATOR P300 TO THE PTGES1 GENE AND THAT HDACI PREVENTED THIS EFFECT. IN LINE WITH THE ACETYLTRANSFERASE ACTIVITY OF P300, H3K27 ACETYLATION WAS REDUCED AFTER HDACI AND RESULTED IN THE FORMATION OF HETEROCHROMATIN IN THE PTGES1 GENE. IN CONCLUSION, HDAC ACTIVITY MAINTAINS PTGES1 EXPRESSION BY RECRUITING P300 TO ITS GENE. 2017 19 4171 43 MEGAKARYOCYTIC LEUKEMIA 1 DIRECTS A HISTONE H3 LYSINE 4 METHYLTRANSFERASE COMPLEX TO REGULATE HYPOXIC PULMONARY HYPERTENSION. ENHANCED INTERACTION BETWEEN VASCULAR ENDOTHELIAL CELLS AND CIRCULATING LEUKOCYTES, AS A RESULT OF TRANSCRIPTIONAL ACTIVATION OF CELL ADHESION MOLECULES (CAM), HELPS ESTABLISH A PROINFLAMMATORY MILIEU CONTRIBUTING TO THE PATHOGENESIS OF CHRONIC HYPOXIA-INDUCED PULMONARY HYPERTENSION. THE MOLECULAR SWITCH THAT DICTATES CAM TRANSACTIVATION IS NOT CLEARLY DEFINED. OUR GOAL WAS TO DETERMINE THE INVOLVEMENT OF THE TRANSCRIPTIONAL MODULATOR MEGAKARYOCYTIC LEUKEMIA 1 (MKL1), ALSO KNOWN AS MYOCARDIN-RELATED TRANSCRIPTION FACTOR A (MRTF-A), IN CAM TRANSACTIVATION AND THE UNDERLYING MECHANISM. WE REPORT HERE THAT COMPARED WITH WILD-TYPE LITTERMATES, MKL1/MRTF-A KNOCKOUT MICE WERE MORE RESISTANT TO THE DEVELOPMENT OF HYPOXIA-INDUCED PULMONARY HYPERTENSION WHEN EXPOSED TO LOW OXYGEN PRESSURE. NOTABLY, CAM INDUCTION IN KNOCKOUT MICE WAS SIGNIFICANTLY ATTENUATED WITH A CONCOMITANT REDUCTION OF LEUKOCYTE ADHESION. IN CULTURED VASCULAR ENDOTHELIAL CELLS, OVEREXPRESSION OF MKL1/MRTF-A ENHANCED, WHEREAS DEPLETION OF MKL1/MRTF-A DAMPENED, HYPOXIA-INDUCED CAM TRANSACTIVATION. IN RESPONSE TO HYPOXIA, MKL1/MRTF-A FORMED A COMPLEX WITH NF-KAPPAB ON THE CAM PROMOTERS. OF INTEREST, MKL1/MRTF-A WAS RESPONSIBLE FOR RECRUITING A HISTONE H3 LYSINE 4 METHYLTRANSFERASE COMPLEX TO THE CAM PROMOTERS. FINALLY, ENDOTHELIAL-SPECIFIC SILENCING OF ASH2 AND WDR5, 2 KEY COMPONENTS OF THE HISTONE H3 LYSINE 4 METHYLTRANSFERASE COMPLEX, AMELIORATED HYPOXIA-INDUCED PULMONARY HYPERTENSION IN MICE. IN CONCLUSION, OUR DATA SUGGEST THAT MKL1/MRTF-A, BY COORDINATING KEY EPIGENETIC ALTERATIONS ON CAM PROMOTERS, PROVIDES A CRITICAL LINK TO HYPOXIA-INDUCED ENDOTHELIAL MALFUNCTION AND CONTRIBUTES TO THE PATHOGENESIS OF HYPOXIA-INDUCED PULMONARY HYPERTENSION. 2015 20 3153 37 GLUCOSE-INDUCED EXPRESSION OF THE HOMEOTIC TRANSCRIPTION FACTOR PREP1 IS ASSOCIATED WITH HISTONE POST-TRANSLATIONAL MODIFICATIONS IN SKELETAL MUSCLE. AIMS/HYPOTHESIS: CHRONIC HYPERGLYCAEMIA WORSENS INSULIN RESISTANCE IN INDIVIDUALS WITH TYPE 2 DIABETES. WHETHER THIS EFFECT IS CONTRIBUTED BY EPIGENETIC DYSREGULATION AND WHICH GENES ARE INVOLVED REMAIN UNCLEAR. PREP1 (ALSO KNOWN AS PKNOX1) IS A GENE EXERTING MAJOR EFFECTS ON THE SENSITIVITY OF THE GLUCOSE TRANSPORT MACHINERY TO INSULIN. HERE, WE SHOW THAT DYSREGULATION OF PREP1 EXPRESSION BY HIGH GLUCOSE LEVELS IS ASSOCIATED WITH HISTONE MODIFICATIONS AT ITS 5' REGULATORY REGION. METHODS: WE USED MOUSE AND CELL MODELS TO INVESTIGATE PREP1 TRANSCRIPTIONAL REGULATION BY GLUCOSE. RESULTS: DIFFERENTIATED L6 SKELETAL MUSCLE CELLS WERE GROWN IN THE PRESENCE OF EITHER 5.5 OR 25 MMOL/L GLUCOSE (NORMAL [NG] AND HIGH GLUCOSE [HG], RESPECTIVELY). THE HG EXPOSURE INCREASED NUCLEAR FACTOR KAPPA LIGHT CHAIN ENHANCER OF ACTIVATED B CELLS (NF-KAPPAB) P65 BINDING AND RECRUITMENT OF THE SU(VAR)3-9, ENHANCER-OF-ZESTE, TRITHORAX DOMAIN-CONTAINING LYSINE METHYLTRANSFERASE 7 (SET7) HISTONE METHYLTRANSFERASE AND P300 ACETYLTRANSFERASE TO THE 5' REGION OF PREP1, LEADING TO ENHANCED TRANSCRIPTION. IN ADDITION, CHROMATIN IMMUNOPRECIPITATION ASSAYS REVEALED CONCOMITANTLY INCREASED HISTONE H3 MONO- AND DIMETHYLATION AND ACETYLATION AT LYS4 AND LYS9/14, RESPECTIVELY. SKELETAL MUSCLE TISSUE FROM STREPTOZOTOCIN-TREATED DIABETIC MICE ALSO SHOWED PREP1 OVEREXPRESSION ACCOMPANIED BY SIMILARLY INCREASED RECRUITMENT OF NF-KAPPAB P65 AND HISTONE MODIFICATIONS AT THE 5' REGION OF PREP1. IN THESE SAME MICE, AS WELL AS IN PREP1-OVEREXPRESSING L6 CELLS, PREP1-INDUCED RECRUITMENT OF THE REPRESSOR COMPLEX MYOCYTE ENHANCER FACTOR 2 (MEF2)/HISTONE DEACETYLASE 5 (HDAC5) AT THE GLUT4 PROMOTER WAS ALSO INCREASED, LEADING TO REDUCED GLUT4 EXPRESSION. CONCLUSIONS/INTERPRETATION: THESE STUDIES INDICATE THAT HG EXPOSURE INDUCES NF-KAPPAB RECRUITMENT AND HISTONE MODIFICATION AT THE PREP1 5' REGION, THEREBY ENHANCING THE TRANSCRIPTION OF PREP1 AND REPRESSING THAT OF GLUT4. HISTONE CHANGES AT THE PREP1 GENE MAY CONTRIBUTE TO INSULIN RESISTANCE IN INDIVIDUALS WITH TYPE 2 DIABETES. 2016