1 5601 105 RORALPHA IS CRUCIAL FOR ATTENUATED INFLAMMATORY RESPONSE TO MAINTAIN INTESTINAL HOMEOSTASIS. RETINOIC ACID-RELATED ORPHAN RECEPTOR ALPHA (RORALPHA) FUNCTIONS AS A TRANSCRIPTION FACTOR FOR VARIOUS BIOLOGICAL PROCESSES, INCLUDING CIRCADIAN RHYTHM, CANCER, AND METABOLISM. HERE, WE GENERATE INTESTINAL EPITHELIAL CELL (IEC)-SPECIFIC RORALPHA-DEFICIENT (RORALPHA(DELTAIEC)) MICE AND FIND THAT RORALPHA IS CRUCIAL FOR MAINTAINING INTESTINAL HOMEOSTASIS BY ATTENUATING NUCLEAR FACTOR KAPPAB (NF-KAPPAB) TRANSCRIPTIONAL ACTIVITY. RORALPHA(DELTAIEC) MICE EXHIBIT EXCESSIVE INTESTINAL INFLAMMATION AND HIGHLY ACTIVATED INFLAMMATORY RESPONSES IN THE DEXTRAN SULFATE SODIUM (DSS) MOUSE COLITIS MODEL. TRANSCRIPTOME ANALYSIS REVEALS THAT DELETION OF RORALPHA LEADS TO UP-REGULATION OF NF-KAPPAB TARGET GENES IN IECS. CHROMATIN IMMUNOPRECIPITATION ANALYSIS REVEALS CORECRUITMENT OF RORALPHA AND HISTONE DEACETYLASE 3 (HDAC3) ON NF-KAPPAB TARGET PROMOTERS AND SUBSEQUENT DISMISSAL OF CREB BINDING PROTEIN (CBP) AND BROMODOMAIN-CONTAINING PROTEIN 4 (BRD4) FOR TRANSCRIPTIONAL REPRESSION. TOGETHER, WE DEMONSTRATE THAT RORALPHA/HDAC3-MEDIATED ATTENUATION OF NF-KAPPAB SIGNALING CONTROLS THE BALANCE OF INFLAMMATORY RESPONSES, AND THERAPEUTIC STRATEGIES TARGETING THIS EPIGENETIC REGULATION COULD BE BENEFICIAL TO THE TREATMENT OF CHRONIC INFLAMMATORY DISEASES, INCLUDING INFLAMMATORY BOWEL DISEASE (IBD). 2019 2 35 27 A CHROMATIN ACTIVITY-BASED CHEMOPROTEOMIC APPROACH REVEALS A TRANSCRIPTIONAL REPRESSOME FOR GENE-SPECIFIC SILENCING. IMMUNE CELLS DEVELOP ENDOTOXIN TOLERANCE (ET) AFTER PROLONGED STIMULATION. ET INCREASES THE LEVEL OF A REPRESSION MARK H3K9ME2 IN THE TRANSCRIPTIONALLY SILENT CHROMATIN SPECIFICALLY ASSOCIATED WITH PRO-INFLAMMATORY GENES. HOWEVER, IT IS NOT CLEAR WHAT PROTEINS ARE FUNCTIONALLY INVOLVED IN THIS PROCESS. HERE WE SHOW THAT A NOVEL CHROMATIN ACTIVITY-BASED CHEMOPROTEOMIC (CHAC) APPROACH CAN DISSECT THE FUNCTIONAL CHROMATIN PROTEIN COMPLEXES THAT REGULATE ET-ASSOCIATED INFLAMMATION. USING UNC0638 THAT BINDS THE ENZYMATICALLY ACTIVE H3K9-SPECIFIC METHYLTRANSFERASE G9A/GLP, CHAC REVEALS THAT G9A IS CONSTITUTIVELY ACTIVE AT A G9A-DEPENDENT MEGA-DALTON REPRESSOME IN PRIMARY ENDOTOXIN-TOLERANT MACROPHAGES. G9A/GLP BROADLY IMPACTS THE ET-SPECIFIC REPROGRAMMING OF THE HISTONE CODE LANDSCAPE, CHROMATIN REMODELLING AND THE ACTIVITIES OF SELECT TRANSCRIPTION FACTORS. WE DISCOVER THAT THE G9A-DEPENDENT EPIGENETIC ENVIRONMENT PROMOTES THE TRANSCRIPTIONAL REPRESSION ACTIVITY OF C-MYC FOR GENE-SPECIFIC CO-REGULATION OF CHRONIC INFLAMMATION. CHAC MAY ALSO BE APPLICABLE TO DISSECT OTHER FUNCTIONAL PROTEIN COMPLEXES IN THE CONTEXT OF PHENOTYPIC CHROMATIN ARCHITECTURES. 2014 3 2080 37 EPIGENETIC DNA METHYLATION OF EBI3 MODULATES HUMAN INTERLEUKIN-35 FORMATION VIA NFKB SIGNALING: A PROMISING THERAPEUTIC OPTION IN ULCERATIVE COLITIS. ULCERATIVE COLITIS (UC), A SEVERE CHRONIC DISEASE WITH UNCLEAR ETIOLOGY THAT IS ASSOCIATED WITH INCREASED RISK FOR COLORECTAL CANCER, IS ACCOMPANIED BY DYSREGULATION OF CYTOKINES. EPSTEIN-BARR VIRUS-INDUCED GENE 3 (EBI3) ENCODES A SUBUNIT IN THE UNIQUE HETERODIMERIC IL-12 CYTOKINE FAMILY OF EITHER PRO- OR ANTI-INFLAMMATORY FUNCTION. AFTER HAVING RECENTLY DEMONSTRATED THAT UPREGULATION OF EBI3 BY HISTONE ACETYLATION ALLEVIATES DISEASE SYMPTOMS IN A DEXTRAN SULFATE SODIUM (DSS)-TREATED MOUSE MODEL OF CHRONIC COLITIS, WE NOW AIMED TO EXAMINE A POSSIBLE FURTHER EPIGENETIC REGULATION OF EBI3 BY DNA METHYLATION UNDER INFLAMMATORY CONDITIONS. TREATMENT WITH THE DNA METHYLTRANSFERASE INHIBITOR (DNMTI) DECITABINE (DAC) AND TNFALPHA LED TO SYNERGISTIC UPREGULATION OF EBI3 IN HUMAN COLON EPITHELIAL CELLS (HCEC). USE OF DIFFERENT SIGNALING PATHWAY INHIBITORS INDICATED NFKAPPAB SIGNALING WAS NECESSARY AND PROPORTIONAL TO THE SYNERGISTIC EBI3 INDUCTION. MALDI-TOF/MS AND HPLC-ESI-MS/MS ANALYSIS OF DAC/TNFALPHA-TREATED HCEC IDENTIFIED IL-12P35 AS THE MOST PROBABLE BINDING PARTNER TO FORM A FUNCTIONAL PROTEIN. EBI3/IL-12P35 HETERODIMERS (IL-35) INDUCE THEIR OWN GENE UPREGULATION, SOMETHING THAT WAS INDEED OBSERVED IN HCEC CULTURED WITH MEDIA FROM PREVIOUSLY DAC/TNFALPHA-TREATED HCEC. THESE RESULTS SUGGEST THAT UNDER INFLAMMATORY AND DEMETHYLATING CONDITIONS THE UPREGULATION OF EBI3 RESULTS IN THE FORMATION OF ANTI-INFLAMMATORY IL-35, WHICH MIGHT BE CONSIDERED AS A THERAPEUTIC TARGET IN COLITIS. 2021 4 4696 28 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 5 5863 33 SUPPRESSION OF ALLERGIC ASTHMA BY LOSS OF FUNCTION OF MIZ1-MEDIATED TH1 SKEWING. ASTHMA IS THE MOST PREVALENT CHRONIC RESPIRATORY DISEASE WORLDWIDE. THERE IS CURRENTLY NO CURE, AND IT REMAINS AN IMPORTANT CAUSE OF MORBIDITY AND MORTALITY. HERE WE REPORT THAT LUNG-SPECIFIC LOSS OF FUNCTION OF THE TRANSCRIPTION FACTOR MIZ1 (C-MYC-INTERACTING ZINC FINGER PROTEIN-1) UPREGULATES THE PRO-T-HELPER CELL TYPE 1 CYTOKINE IL-12. UPREGULATION OF IL-12 IN TURN STIMULATES A TH1 RESPONSE, THEREBY COUNTERACTING T-HELPER CELL TYPE 2 RESPONSE AND PREVENTING THE ALLERGIC RESPONSE IN MOUSE MODELS OF HOUSE DUST MITE- AND OVA (OVALBUMIN)-INDUCED ASTHMA. USING TRANSGENIC MICE EXPRESSING CRE UNDER A CELL-SPECIFIC PROMOTER, WE DEMONSTRATE THAT MIZ1 ACTS IN LUNG EPITHELIAL CELLS AND DENDRITIC CELLS IN ASTHMA. CHROMATIN IMMUNOPRECIPITATION COUPLED WITH HIGH-THROUGHPUT DNA SEQUENCING OR QUANTITATIVE PCR REVEALS THE BINDING OF MIZ1 ON THE IL12 PROMOTER INDICATING DIRECT REPRESSION OF IL-12 BY MIZ1. IN ADDITION, HDAC1 (HISTONE DEACETYLASE 1) IS RECRUITED TO THE IL12 PROMOTER IN A MIZ1-DEPDENENT MANNER, SUGGESTING EPIGENETIC REPRESSION OF IL12 BY MIZ1. FURTHERMORE, MIZ1 IS UPREGULATED IN THE LUNGS OF ASTHMATIC MICE. OUR DATA TOGETHER SUGGEST THAT MIZ1 IS UPREGULATED DURING ASTHMA, WHICH IN TURN PROMOTES ASTHMA PATHOGENESIS BY PREVENTING TH1 SKEWING THROUGH THE TRANSCRIPTIONAL REPRESSION OF IL-12. 2022 6 460 32 ARACHIDONIC ACID 15-LIPOXYGENASE: EFFECTS OF ITS EXPRESSION, METABOLITES, AND GENETIC AND EPIGENETIC VARIATIONS ON AIRWAY INFLAMMATION. ARACHIDONIC ACID 15-LIPOXYGENASE (ALOX15) IS AN ENZYME THAT CAN OXIDIZE POLYUNSATURATED FATTY ACIDS. ALOX15 IS STRONGLY EXPRESSED IN AIRWAY EPITHELIAL CELLS, WHERE IT CATALYZES THE CONVERSION OF ARACHIDONIC ACID TO 15-HYDROXYEICOSATETRAENOIC ACID (15-HETE) INVOLVED IN VARIOUS AIRWAY INFLAMMATORY DISEASES. INTERLEUKIN (IL)-4 AND IL-13 INDUCE ALOX15 EXPRESSION BY ACTIVATING JAK2 AND TYK2 KINASES AS WELL AS SIGNAL TRANSDUCERS AND ACTIVATORS OF TRANSCRIPTION (STATS) 1/3/5/6. ALOX15 UP-REGULATION AND SUBSEQUENT ASSOCIATION WITH PHOSPHATIDYLETHANOLAMINE-BINDING PROTEIN 1 (PEBP1) ACTIVATE THE MITOGEN-ACTIVATED EXTRACELLULAR SIGNAL-REGULATED KINASE (MEK)-EXTRACELLULAR SIGNAL-REGULATED KINASE (ERK) PATHWAY, THUS INDUCING EOSINOPHIL-MEDIATED AIRWAY INFLAMMATION. IN ADDITION, ALOX15 PLAYS A SIGNIFICANT ROLE IN PROMOTING THE MIGRATION OF IMMUNE CELLS, SUCH AS IMMATURE DENDRITIC CELLS, ACTIVATED T CELLS, AND MAST CELLS, AND AIRWAY REMODELING, INCLUDING GOBLET CELL DIFFERENTIATION. GENOME-WIDE ASSOCIATION STUDIES HAVE REVEALED MULTIPLE ALOX15 VARIANTS AND THEIR SIGNIFICANT CORRELATION WITH THE RISK OF DEVELOPING AIRWAY DISEASES. THE EPIGENETIC MODIFICATIONS OF THE ALOX15 GENE, SUCH AS DNA METHYLATION AND HISTONE MODIFICATIONS, HAVE BEEN SHOWN TO CLOSELY RELATE WITH AIRWAY INFLAMMATION. THIS REVIEW SUMMARIZES THE ROLE OF ALOX15 IN DIFFERENT PHENOTYPES OF ASTHMA, CHRONIC OBSTRUCTIVE PULMONARY DISEASE, CHRONIC RHINOSINUSITIS, ASPIRIN-EXACERBATED RESPIRATORY DISEASE, AND NASAL POLYPS, SUGGESTING NEW TREATMENT STRATEGIES FOR THESE AIRWAY INFLAMMATORY DISEASES WITH COMPLEX ETIOLOGY AND POOR TREATMENT RESPONSE. 2021 7 768 32 CD47 (CLUSTER OF DIFFERENTIATION 47). CD47, ALSO KNOWN AS INTEGRIN-ASSOCIATED PROTEIN, IS A CONSTITUTIVELY AND UBIQUITOUSLY EXPRESSED TRANSMEMBRANE RECEPTOR. CD47 IS CONSERVED ACROSS AMNIOTES INCLUDING MAMMALS, REPTILES, AND BIRDS. EXPRESSION IS INCREASED IN MANY CANCERS AND, IN NON-MALIGNANT CELLS, BY STRESS AND WITH AGING. THE UP-REGULATION OF CD47 EXPRESSION IS GENERALLY EPIGENETIC, WHEREAS GENE AMPLIFICATION OCCURS WITH LOW FREQUENCY IN SOME CANCERS. CD47 IS A HIGH AFFINITY SIGNALING RECEPTOR FOR THE SECRETED PROTEIN THROMBOSPONDIN-1 (THBS1) AND THE COUNTER-RECEPTOR FOR SIGNAL REGULATORY PROTEIN-ALPHA (SIRPA, SIRPALPHA) AND SIRPGAMMA (SIRPG). CD47 INTERACTION WITH SIRPALPHA SERVES AS A MARKER OF SELF TO INNATE IMMUNE CELLS AND THEREBY PROTECTS CANCER CELLS FROM PHAGOCYTIC CLEARANCE. CONSEQUENTLY, HIGHER CD47 CORRELATES WITH A POOR PROGNOSIS IN SOME CANCERS, AND THERAPEUTIC BLOCKADE CAN SUPPRESS TUMOR GROWTH BY ENHANCING INNATE ANTITUMOR IMMUNITY. CD47 EXPRESSED ON CYTOTOXIC T CELLS, DENDRITIC CELLS, AND NK CELLS MEDIATES INHIBITORY THBS1 SIGNALING THAT FURTHER LIMITS ANTITUMOR IMMUNITY. CD47 LATERALLY ASSOCIATES WITH SEVERAL INTEGRINS AND THEREBY REGULATES CELL ADHESION AND MIGRATION. CD47 HAS ADDITIONAL LATERAL BINDING PARTNERS IN SPECIFIC CELL TYPES, AND LIGATION OF CD47 IN SOME CASES MODULATES THEIR FUNCTION. THBS1-CD47 SIGNALING IN NON-MALIGNANT CELLS INHIBITS NITRIC OXIDE/CGMP, CALCIUM, AND VEGF SIGNALING, MITOCHONDRIAL HOMEOSTASIS, STEM CELL MAINTENANCE, PROTECTIVE AUTOPHAGY, AND DNA DAMAGE RESPONSE, AND PROMOTES NADPH OXIDASE ACTIVITY. CD47 SIGNALING IS A PHYSIOLOGICAL REGULATOR OF PLATELET ACTIVATION, ANGIOGENESIS AND BLOOD FLOW. THBS1/CD47 SIGNALING IS FREQUENTLY DYSREGULATED IN CHRONIC DISEASES. 2021 8 4867 25 OSSIFYING FIBROMA TUMOR STEM CELLS ARE MAINTAINED BY EPIGENETIC REGULATION OF A TSP1/TGF-BETA/SMAD3 AUTOCRINE LOOP. ABNORMAL STEM CELL FUNCTION MAKES A KNOWN CONTRIBUTION TO MANY MALIGNANT TUMORS, BUT THE ROLE OF STEM CELLS IN BENIGN TUMORS IS NOT WELL UNDERSTOOD. HERE, WE SHOW THAT OSSIFYING FIBROMA (OF) CONTAINS A STEM CELL POPULATION THAT RESEMBLES MESENCHYMAL STEM CELLS (OFMSCS) AND IS CAPABLE OF GENERATING OF-LIKE TUMOR XENOGRAFTS. MECHANISTICALLY, OFMSCS SHOW ENHANCED TGF-BETA SIGNALING THAT INDUCES ABERRANT PROLIFERATION AND DEFICIENT OSTEOGENESIS VIA NOTCH AND BMP SIGNALING PATHWAYS, RESPECTIVELY. THE ELEVATED TGF-BETA ACTIVITY IS TIGHTLY REGULATED BY JHDM1D-MEDIATED EPIGENETIC REGULATION OF THROMBOSPONDIN-1 (TSP1), FORMING A JHDM1D/TSP1/TGF-BETA/SMAD3 AUTOCRINE LOOP. INHIBITION OF TGF-BETA SIGNALING IN OFMSCS CAN RESCUE THEIR ABNORMAL OSTEOGENIC DIFFERENTIATION AND ELEVATED PROLIFERATION RATE. FURTHERMORE, CHRONIC ACTIVATION OF TGF-BETA CAN CONVERT NORMAL MSCS INTO OF-LIKE MSCS VIA ESTABLISHMENT OF THIS JHDM1D/TSP1/TGF-BETA/SMAD3 AUTOCRINE LOOP. THESE RESULTS REVEAL THAT EPIGENETIC REGULATION OF TGF-BETA SIGNALING IN MSCS GOVERNS THE BENIGN TUMOR PHENOTYPE IN OF AND HIGHLIGHT TGF-BETA SIGNALING AS A CANDIDATE THERAPEUTIC TARGET. 2013 9 2155 30 EPIGENETIC MECHANISMS AND METABOLIC REPROGRAMMING IN FIBROGENESIS: DUAL TARGETING OF G9A AND DNMT1 FOR THE INHIBITION OF LIVER FIBROSIS. OBJECTIVE: HEPATIC STELLATE CELLS (HSC) TRANSDIFFERENTIATION INTO MYOFIBROBLASTS IS CENTRAL TO FIBROGENESIS. EPIGENETIC MECHANISMS, INCLUDING HISTONE AND DNA METHYLATION, PLAY A KEY ROLE IN THIS PROCESS. CONCERTED ACTION BETWEEN HISTONE AND DNA-MEHYLTRANSFERASES LIKE G9A AND DNMT1 IS A COMMON THEME IN GENE EXPRESSION REGULATION. WE AIMED TO STUDY THE EFFICACY OF CM272, A FIRST-IN-CLASS DUAL AND REVERSIBLE G9A/DNMT1 INHIBITOR, IN HALTING FIBROGENESIS. DESIGN: G9A AND DNMT1 WERE ANALYSED IN CIRRHOTIC HUMAN LIVERS, MOUSE MODELS OF LIVER FIBROSIS AND CULTURED MOUSE HSC. G9A AND DNMT1 EXPRESSION WAS KNOCKED DOWN OR INHIBITED WITH CM272 IN HUMAN HSC (HHSC), AND TRANSCRIPTOMIC RESPONSES TO TRANSFORMING GROWTH FACTOR-BETA1 (TGFBETA1) WERE EXAMINED. GLYCOLYTIC METABOLISM AND MITOCHONDRIAL FUNCTION WERE ANALYSED WITH SEAHORSE-XF TECHNOLOGY. GENE EXPRESSION REGULATION WAS ANALYSED BY CHROMATIN IMMUNOPRECIPITATION AND METHYLATION-SPECIFIC PCR. ANTIFIBROGENIC ACTIVITY AND SAFETY OF CM272 WERE STUDIED IN MOUSE CHRONIC CCL(4) ADMINISTRATION AND BILE DUCT LIGATION (BDL), AND IN HUMAN PRECISION-CUT LIVER SLICES (PCLSS) IN A NEW BIOREACTOR TECHNOLOGY. RESULTS: G9A AND DNMT1 WERE DETECTED IN STROMAL CELLS IN AREAS OF ACTIVE FIBROSIS IN HUMAN AND MOUSE LIVERS. G9A AND DNMT1 EXPRESSION WAS INDUCED DURING MOUSE HSC ACTIVATION, AND TGFBETA1 TRIGGERED THEIR CHROMATIN RECRUITMENT IN HHSC. G9A/DNMT1 KNOCKDOWN AND CM272 INHIBITED TGFBETA1 FIBROGENIC RESPONSES IN HHSC. TGFBETA1-MEDIATED PROFIBROGENIC METABOLIC REPROGRAMMING WAS ABROGATED BY CM272, WHICH RESTORED GLUCONEOGENIC GENE EXPRESSION AND MITOCHONDRIAL FUNCTION THROUGH ON-TARGET EPIGENETIC EFFECTS. CM272 INHIBITED FIBROGENESIS IN MICE AND PCLSS WITHOUT TOXICITY. CONCLUSIONS: DUAL G9A/DNMT1 INHIBITION BY COMPOUNDS LIKE CM272 MAY BE A NOVEL THERAPEUTIC STRATEGY FOR TREATING LIVER FIBROSIS. 2021 10 5009 25 PERK IS A CRITICAL METABOLIC HUB FOR IMMUNOSUPPRESSIVE FUNCTION IN MACROPHAGES. CHRONIC INFLAMMATION TRIGGERS COMPENSATORY IMMUNOSUPPRESSION TO STOP INFLAMMATION AND MINIMIZE TISSUE DAMAGE. STUDIES HAVE DEMONSTRATED THAT ENDOPLASMIC RETICULUM (ER) STRESS AUGMENTS THE SUPPRESSIVE PHENOTYPES OF IMMUNE CELLS; HOWEVER, THE MOLECULAR MECHANISMS UNDERPINNING THIS PROCESS AND HOW IT LINKS TO THE METABOLIC REPROGRAMMING OF IMMUNOSUPPRESSIVE MACROPHAGES REMAIN ELUSIVE. IN THE PRESENT STUDY, WE REPORT THAT THE HELPER T CELL 2 CYTOKINE INTERLEUKIN-4 AND THE TUMOR MICROENVIRONMENT INCREASE THE ACTIVITY OF A PROTEIN KINASE RNA-LIKE ER KINASE (PERK)-SIGNALING CASCADE IN MACROPHAGES AND PROMOTE IMMUNOSUPPRESSIVE M2 ACTIVATION AND PROLIFERATION. LOSS OF PERK SIGNALING IMPEDED MITOCHONDRIAL RESPIRATION AND LIPID OXIDATION CRITICAL FOR M2 MACROPHAGES. PERK ACTIVATION MEDIATED THE UPREGULATION OF PHOSPHOSERINE AMINOTRANSFERASE 1 (PSAT1) AND SERINE BIOSYNTHESIS VIA THE DOWNSTREAM TRANSCRIPTION FACTOR ATF-4. INCREASED SERINE BIOSYNTHESIS RESULTED IN ENHANCED MITOCHONDRIAL FUNCTION AND ALPHA-KETOGLUTARATE PRODUCTION REQUIRED FOR JMJD3-DEPENDENT EPIGENETIC MODIFICATION. INHIBITION OF PERK SUPPRESSED MACROPHAGE IMMUNOSUPPRESSIVE ACTIVITY AND COULD ENHANCE THE EFFICACY OF IMMUNE CHECKPOINT PROGRAMMED CELL DEATH PROTEIN 1 INHIBITION IN MELANOMA. OUR FINDINGS DELINEATE A PREVIOUSLY UNDESCRIBED CONNECTION BETWEEN PERK SIGNALING AND PSAT1-MEDIATED SERINE METABOLISM CRITICAL FOR PROMOTING IMMUNOSUPPRESSIVE FUNCTION IN M2 MACROPHAGES. 2022 11 3161 28 GRAINYHEAD-LIKE 2 (GRHL2) INHIBITS KERATINOCYTE DIFFERENTIATION THROUGH EPIGENETIC MECHANISM. WE RECENTLY IDENTIFIED GRAINYHEAD-LIKE 2 (GRHL2), A MAMMALIAN HOMOLOG OF GRAINYHEAD IN DROSOPHILA, TO BE A NOVEL TRANSCRIPTION FACTOR THAT REGULATES HTERT GENE EXPRESSION AND ENHANCES PROLIFERATION OF NORMAL HUMAN EPIDERMAL KERATINOCYTES (NHEK). IN THE CURRENT STUDY, WE SHOW THAT GRHL2 IMPAIRS KERATINOCYTE DIFFERENTIATION THROUGH TRANSCRIPTIONAL INHIBITION OF THE GENES CLUSTERED AT THE EPIDERMAL DIFFERENTIATION COMPLEX (EDC), LOCATED AT CHROMOSOME 1Q21. GENE EXPRESSION PROFILING AND SUBSEQUENT IN VITRO ASSAYS REVEALED CONSISTENT DOWNREGULATION OF EDC GENES, FOR EXAMPLE, IVL, KRT1, FLG, LCES, AND SPRRS, IN NHEK EXPRESSING EXOGENOUS GRHL2. IN VIVO BINDING ASSAY BY CHROMATIN IMMUNOPRECIPITATION REVEALED GRHL2 ASSOCIATION AT THE PROMOTER REGIONS OF ITS TARGET GENES, MANY OF WHICH BELONG TO EDC. EXOGENOUS GRHL2 EXPRESSION ALSO INHIBITED RECRUITMENT OF HISTONE DEMETHYLASE JMJD3 TO THE EDC GENE PROMOTERS AND ENHANCED THE LEVEL OF HISTONE 3 LYS 27 TRIMETHYLATION ENRICHMENT AT THESE PROMOTERS. SURVEY OF GRHL2 EXPRESSION IN HUMAN SKIN TISSUES DEMONSTRATED ENHANCED PROTEIN AND MRNA LEVELS IN CHRONIC SKIN LESIONS WITH IMPAIRED KERATINOCYTE DIFFERENTIATION, FOR EXAMPLE, ATOPIC DERMATITIS AND PSORIASIS, COMPARED WITH NORMAL EPIDERMIS. THESE DATA INDICATE THAT GRHL2 IMPAIRS EPIDERMAL DIFFERENTIATION BY INHIBITING EDC GENE EXPRESSION THROUGH EPIGENETIC MECHANISMS AND SUPPORT ITS ROLE IN THE HYPERPROLIFERATIVE SKIN DISEASES. 2012 12 3128 36 GIPC-REGULATED IGFBP-3 PROMOTES HSC MIGRATION IN VITRO AND PORTAL HYPERTENSION IN VIVO THROUGH A BETA1-INTEGRIN PATHWAY. BACKGROUND & AIMS: TRANSFORMING GROWTH FACTOR (TGF-BETA)-INDUCED ACTIVATION OF QUIESCENT HEPATIC STELLATE CELLS (HSCS) AND THEIR TRANSFORMATION TO MYOFIBROBLASTS IS A KEY EVENT IN LIVER FIBROSIS AND PORTAL HYPERTENSION. GIPC (ALSO REFERRED TO AS SYNECTIN) IS A DOWNSTREAM SIGNAL ACTIVATION MOLECULE OF TGF-BETA AND OTHER RECEPTORS. IN THIS STUDY, WE SOUGHT TO IDENTIFY NOVEL GENES TARGETED BY TGF-BETA AND GIPC AND ELUCIDATE IF AND HOW THEY MAY CONTRIBUTE TO LIVER FIBROSIS. METHODS: WE PERFORMED SEQUENTIAL MESSENGER RNA SEQUENCING ANALYSIS ON TGF-BETA-STIMULATED HSCS AND THEN ON TGF-BETA-STIMULATED HSCS IN THE PRESENCE AND ABSENCE OF GIPC ALSO REFERRED TO AS SYNECTIN (GIPC) KNOCKDOWN. INSULIN-LIKE GROWTH FACTOR BINDING PROTEIN-3 (IGFBP-3) TRANSPORT PROTEIN EMERGED AS A TOP ACTIVATION TARGET OF BOTH TGF-BETA AND GIPC. QUANTITATIVE POLYMERASE CHAIN REACTION, ENZYME-LINKED IMMUNOSORBENT ASSAY, TARGETED CHROMATIN IMMUNOPRECIPITATION, AND WESTERN BLOT ANALYSIS WERE DONE FOR FURTHER CONFIRMATION. RESULTS: IGFBP-3, AN INSULIN GROWTH FACTOR TRANSPORT PROTEIN, EMERGED AS A TOP ACTIVATION TARGET OF BOTH TGF-BETA AND GIPC, WHICH WAS CONFIRMED BY QUANTITATIVE POLYMERASE CHAIN REACTION, ENZYME-LINKED IMMUNOSORBENT ASSAY, AND WESTERN BLOT ANALYSIS. TARGETED CHROMATIN IMMUNOPRECIPITATION SHOWED THAT GIPC INCREASES THE HISTONE 3 LYSINE 27 (H3K27) ACETYLATION ACTIVATING MARK AND CONCURRENTLY DECREASES THE H3K27 INHIBITORY TRIMETHYLATION (H3K27M3) MARK, PROVIDING AN EPIGENETIC CORRELATE TO THE GENE REGULATION CHANGES. IN VIVO, GLOBAL KNOCKOUT OF IGFBP-3 MICE RESULTED IN ATTENUATION OF HSC ACTIVATION MARKERS AND ATTENUATION OF PORTAL PRESSURE IN RESPONSE TO CHRONIC LIVER INJURY MODELS. ANALYSIS OF SERUM LEVELS FROM CIRRHOTIC PATIENTS ALSO SHOWED AN IGFBP-3 INCREASE OF MORE THAN 2-FOLD COMPARED WITH HEALTHY CONTROLS. FINALLY, IN VITRO MECHANISM STUDIES SHOWED THAT IGFBP-3 PROMOTES HSC MIGRATION THROUGH INTEGRIN-DEPENDENT PHOSPHORYLATION OF PROTEIN KINASE B. CONCLUSIONS: TGF-BETA UP-REGULATES IGFBP-3 THROUGH GIPC, LEADING TO INCREASED HSC MIGRATION IN VITRO AND PROMOTES PORTAL HYPERTENSION IN VIVO. THESE STUDIES SUPPORT THE ROLE OF IGFBP-3 AS A POTENTIAL PATHOPHYSIOLOGIC TARGET OR BIOMARKER IN CHRONIC LIVER DISEASE. 2020 13 1777 29 EDIBLE BLUE-GREEN ALGAE REDUCE THE PRODUCTION OF PRO-INFLAMMATORY CYTOKINES BY INHIBITING NF-KAPPAB PATHWAY IN MACROPHAGES AND SPLENOCYTES. BACKGROUND: CHRONIC INFLAMMATION CONTRIBUTES TO THE DEVELOPMENT OF PATHOLOGICAL DISORDERS INCLUDING INSULIN RESISTANCE AND ATHEROSCLEROSIS. IDENTIFICATION OF ANTI-INFLAMMATORY NATURAL PRODUCTS CAN PREVENT THE INFLAMMATORY DISEASES. METHODS: ANTI-INFLAMMATORY EFFECTS OF BLUE-GREEN ALGAE (BGA), I.E., NOSTOC COMMUNE VAR. SPHAEROIDES KUTZING (NO) AND SPIRULINA PLATENSIS (SP), WERE COMPARED IN RAW 264.7 AND MOUSE BONE MARROW-DERIVED MACROPHAGES (BMM) AS WELL AS SPLENOCYTES FROM APOLIPOPROTEIN E KNOCKOUT (APOE(-/-)) MICE FED BGA. RESULTS: WHEN MACROPHAGES PRETREATED WITH 100MUG/ML NO LIPID EXTRACT (NOE) OR SP LIPID EXTRACT (SPE) WERE ACTIVATED BY LIPOPOLYSACCHARIDE (LPS), EXPRESSION AND SECRETION OF PRO-INFLAMMATORY CYTOKINES, SUCH AS TUMOR NECROSIS FACTOR ALPHA (TNFALPHA), INTERLEUKIN 1BETA (IL-1BETA), AND IL-6, WERE SIGNIFICANTLY REPRESSED. NOE AND SPE ALSO SIGNIFICANTLY REPRESSED THE EXPRESSION OF TNFALPHA AND IL-1BETA IN BMM. LPS-INDUCED SECRETION OF IL-6 WAS LOWER IN SPLENOCYTES FROM APOE(-/-) FED AN ATHEROGENIC DIET CONTAINING 5% NO OR SP FOR 12WEEKS. IN RAW 264.7 MACROPHAGES, NOE AND SPE MARKEDLY DECREASED NUCLEAR TRANSLOCATION OF NF-KAPPAB. THE DEGREE OF REPRESSION OF PRO-INFLAMMATORY GENE EXPRESSION BY ALGAL EXTRACTS WAS MUCH STRONGER THAN THAT OF SN50, AN INHIBITOR OF NF-KAPPAB NUCLEAR TRANSLOCATION. TRICHOSTATIN A, A PAN HISTONE DEACETYLASE INHIBITOR, INCREASED BASAL EXPRESSION OF IL-1BETA AND ATTENUATED THE REPRESSION OF THE GENE EXPRESSION BY SPE. SPE SIGNIFICANTLY DOWN-REGULATED MRNA ABUNDANCE OF 11 HDAC ISOFORMS, CONSEQUENTLY INCREASING ACETYLATED HISTONE 3 LEVELS. CONCLUSION: NOE AND SPE REPRESS PRO-INFLAMMATORY CYTOKINE EXPRESSION AND SECRETION IN MACROPHAGES AND SPLENOCYTES VIA INHIBITION OF NF-KAPPAB PATHWAY. HISTONE ACETYLATION STATE IS LIKELY INVOLVED IN THE INHIBITION. GENERAL SIGNIFICANCE: THIS STUDY UNDERSCORES NATURAL PRODUCTS CAN EXERT ANTI-INFLAMMATORY EFFECTS BY EPIGENETIC MODIFICATIONS SUCH AS HISTONE ACETYLATION. 2013 14 685 26 BRAIN-DERIVED NEUROTROPHIC FACTOR INVOLVED EPIGENETIC REPRESSION OF UGT2B7 IN COLORECTAL CARCINOMA: A MECHANISM TO ALTER MORPHINE GLUCURONIDATION IN TUMOR. URIDINE DIPHOSPHATE-GLUCURONOSYLTRANSFERASE (UGT) 2B7, AS ONE OF SIGNIFICANT DRUG ENZYMES, IS RESPONSIBLE ON THE GLUCURONIDATION OF ABUNDANT ENDOBIOTICS OR XENOBIOTICS. WE HERE REPORT THAT IT IS MARKEDLY REPRESSED IN THE TUMOR TISSUES OF COLORECTAL CARCINOMA (CRC) PATIENTS. ACCORDINGLY, MORPHINE IN CRC CELLS WILL STIMULATE THE EXPRESSION OF ITS MAIN METABOLIC ENZYME, UGT2B7 DURING TOLERANCE GENERATION BY ACTIVATING THE POSITIVE SIGNALS IN HISTONE 3, ESPECIALLY FOR TRIMETHYLATED LYSINE 27 (H3K4ME3) AND ACETYLATED LYSINE 4 (H3K27AC). FURTHER STUDY REVEALS THAT BRAIN-DERIVED NEUTROPHILIC FACTOR (BDNF), A SECRETORY NEUROTROPHIN, ENRICHED IN CRC CAN INTERACT AND INHIBIT UGT2B7 BY PRIMARILY BLOCKING THE POSITIVE SIGNALS OF H3K4ME3 AS WELL AS ACTIVATING H3K27AC ON THE PROMOTER REGION OF UGT2B7. MEANWHILE, BDNF REPRESSION ATTRIBUTES TO THE SENSITIZATIONS OF MAIN CORE FACTORS IN POLY-COMB REPRESSIVE COMPLEX (PRC) 1 RATHER THAN PRC2 AS THE REASON OF THE DEPRESSION OF SUZ12 IN THE LATER COMPLEX. BESIDES THAT, THE PRODUCTIONS OF TWO MAIN MORPHINE GLUCURONIDES ARE BOTH INCREASED IN THE BDNF DEFICIENT OR TSA AND BIX-01294 TREATED MORPHINE TOLERANCE-LIKE HCT-116 CELLS. ON THE SAME CONDITION, ACTIVE METABOLITE, MORPHINE-6-GLUCURONIDE (M6G) WAS ACCUMULATED MORE THAN INACTIVE M3G. OUR FINDINGS IMPLY THAT ENZYMATIC ACTIVITY ENHANCEMENT AND SUBSTRATE REGIOSELECTIVE CATALYSIS ALTERATION OF UGT2B7 MAY RELEASE MORPHINE TOLERANCE UNDER THE CURE OF TUMOR-INDUCED PAIN. 2017 15 368 33 AMYLOID BETA-MEDIATED EPIGENETIC ALTERATION OF INSULIN-LIKE GROWTH FACTOR BINDING PROTEIN 3 CONTROLS CELL SURVIVAL IN ALZHEIMER'S DISEASE. SWEDISH DOUBLE MUTATION (KM670/671NL) OF AMYLOID PRECURSOR PROTEIN (APP) IS REPORTED TO INCREASE TOXIC AMYLOID BETA (ABETA) PRODUCTION VIA ABERRANT CLEAVAGE AT THE BETA-SECRETASE SITE AND THEREBY CAUSE EARLY-ONSET ALZHEIMER'S DISEASE (AD). HOWEVER, THE UNDERLYING MOLECULAR MECHANISMS LEADING TO AD PATHOGENESIS REMAINS LARGELY UNKNOWN. PREVIOUSLY, OUR TRANSCRIPTOME SEQUENCE ANALYSES REVEALED GLOBAL EXPRESSIONAL MODIFICATIONS OF OVER 600 GENES IN APP-SWEDISH MUTANT-EXPRESSING H4 (H4-SW) CELLS COMPARED TO WILD TYPE H4 CELLS. INSULIN-LIKE GROWTH FACTOR BINDING PROTEIN 3 (IGFBP3) IS ONE GENE THAT SHOWED SIGNIFICANTLY DECREASED MRNA EXPRESSION IN H4-SW CELLS. IN THIS STUDY, WE INVESTIGATED THE FUNCTIONAL ROLE OF IGFBP3 IN AD PATHOGENESIS AND ELUCIDATED THE MECHANISMS REGULATING ITS EXPRESSION. WE OBSERVED DECREASED IGFBP3 EXPRESSION IN THE H4-SW CELL LINE AS WELL AS THE HIPPOCAMPUS OF AD MODEL TRANSGENIC MICE. TREATMENT WITH EXOGENOUS IGFBP3 PROTEIN INHIBITED ABETA1-42- INDUCED CELL DEATH AND CASPASE-3 ACTIVITY, WHEREAS SIRNA-MEDIATED SUPPRESSION OF IGFBP3 EXPRESSION INDUCED CELL DEATH AND CASPASE-3 CLEAVAGE. IN PRIMARY HIPPOCAMPAL NEURONS, ADMINISTRATION OF IGFBP3 PROTEIN BLOCKED APOPTOTIC CELL DEATH DUE TO ABETA1-42 TOXICITY. THESE DATA IMPLICATE A PROTECTIVE ROLE FOR IGFBP3 AGAINST ABETA1-42-MEDIATED APOPTOSIS. NEXT, WE INVESTIGATED THE REGULATORY MECHANISMS OF IGFBP3 EXPRESSION IN AD PATHOGENESIS. WE OBSERVED ABNORMAL IGFBP3 HYPERMETHYLATION WITHIN THE PROMOTER CPG ISLAND IN H4-SW CELLS. TREATMENT WITH THE DNA METHYLTRANSFERASE INHIBITOR 5-AZA-2'-DEOXYCYTIDINE RESTORED IGFBP3 EXPRESSION AT BOTH THE MRNA AND PROTEIN LEVELS. CHRONIC EXPOSURE TO ABETA1-42 INDUCED IGFBP3 HYPERMETHYLATION AT CPGS, PARTICULARLY AT LOCI -164 AND -173, AND SUBSEQUENTLY SUPPRESSED IGFBP3 EXPRESSION. THEREFORE, WE DEMONSTRATE THAT EXPRESSION OF ANTI-APOPTOTIC IGFBP3 IS REGULATED BY EPIGENETIC DNA METHYLATION, SUGGESTING A MECHANISM THAT CONTRIBUTES TO AD PATHOGENESIS. 2014 16 1806 25 EFFECT OF TRANSCRIPTION INHIBITION AND GENERATION OF SUPPRESSIVE VIRAL NON-CODING RNAS. BACKGROUND: HIV-1 PATIENTS RECEIVING COMBINATION ANTIRETROVIRAL THERAPY (CART) SURVIVE INFECTION BUT REQUIRE LIFE-LONG ADHERENCE AT HIGH EXPENSE. IN CHRONIC CART-TREATED PATIENTS WITH UNDETECTABLE VIRAL TITERS, CELL-ASSOCIATED VIRAL RNA IS STILL DETECTABLE, POINTING TO LOW-LEVEL VIRAL TRANSCRIPTIONAL LEAKINESS. TO DATE, THERE ARE NO FDA-APPROVED DRUGS AGAINST HIV-1 TRANSCRIPTION. WE HAVE PREVIOUSLY SHOWN THAT F07#13, A THIRD GENERATION TAT PEPTIDE MIMETIC WITH COMPETITIVE ACTIVITY AGAINST CDK9/T1-TAT BINDING SITES, INHIBITS HIV-1 TRANSCRIPTION IN VITRO AND IN VIVO. RESULTS: HERE, WE DEMONSTRATE THAT INCREASING CONCENTRATIONS OF F07#13 (0.01, 0.1, 1 MICROM) CAUSE A DECREASE IN TAT LEVELS IN A DOSE-DEPENDENT MANNER BY INHIBITING THE CDK9/T1-TAT COMPLEX FORMATION AND SUBSEQUENT UBIQUITIN-MEDIATED TAT SEQUESTRATION AND DEGRADATION. OUR DATA INDICATE THAT COMPLEXES I AND IV CONTAIN DISTINCT PATTERNS OF UBIQUITINATED TAT AND THAT TRANSCRIPTIONAL INHIBITION INDUCED BY F07#13 CAUSES AN OVERALL REDUCTION IN TAT LEVELS. THIS REDUCTION MAY BE TRIGGERED BY F07#13 BUT ULTIMATELY IS MEDIATED BY TAR-GAG VIRAL RNAS THAT BIND SUPPRESSIVE TRANSCRIPTION FACTORS (SIMILAR TO 7SK, NRON, HOTAIR, AND XIST LNCRNAS) TO ENHANCE TRANSCRIPTIONAL GENE SILENCING AND LATENCY. THESE RNAS COMPLEX WITH PRC2, SIN3A, AND CUL4B, RESULTING IN EPIGENETIC MODIFICATIONS. FINALLY, WE OBSERVED AN F07#13-MEDIATED DECREASE OF VIRAL BURDEN BY TARGETING THE R REGION OF THE LONG TERMINAL REPEAT (HIV-1 PROMOTER REGION, LTR), PROMOTING BOTH PAUSED POLYMERASES AND INCREASED EFFICIENCY OF CRISPR/CAS9 EDITING IN INFECTED CELLS. THIS IMPLIES THAT GENE EDITING MAY BE BEST PERFORMED UNDER A REPRESSED TRANSCRIPTIONAL STATE. CONCLUSIONS: COLLECTIVELY, OUR RESULTS INDICATE THAT F07#13, WHICH CAN TERMINATE RNA POLYMERASE II AT DISTINCT SITES, CAN GENERATE SCAFFOLD RNAS, WHICH MAY ASSEMBLE INTO SPECIFIC SETS OF "RNA MACHINES" THAT CONTRIBUTE TO GENE REGULATION. IT REMAINS TO BE SEEN WHETHER THESE EFFECTS CAN ALSO BE SEEN IN VARIOUS CLADES THAT HAVE VARYING PROMOTER STRENGTH, MUTANT LTRS, AND IN PATIENT SAMPLES. 2019 17 1668 27 DOWNREGULATION OF SOCS1 INCREASES INTERFERON-INDUCED ISGYLATION DURING DIFFERENTIATION OF INDUCED-PLURIPOTENT STEM CELLS TO HEPATOCYTES. BACKGROUND & AIMS: INCREASED EXPRESSION OF IFN-STIMULATED GENE 15 (ISG15) AND SUBSEQUENTLY INCREASED ISGYLATION ARE KEY FACTORS IN THE HOST RESPONSE TO VIRAL INFECTION. IN THIS STUDY, WE SOUGHT TO CHARACTERIZE THE EXPRESSION OF ISG15, ISGYLATION, AND ASSOCIATED ENZYMES AT EACH STAGE OF DIFFERENTIATION FROM INDUCED PLURIPOTENT STEM CELLS (IPSCS) TO HEPATOCYTES. METHODS: TO STUDY THE REGULATION OF ISGYLATION, WE UTILIZED PATIENT SAMPLES AND IN VITRO CELL CULTURE MODELS INCLUDING IPSCS, HEPATOCYTES-LIKE CELLS, IMMORTALIZED CELL LINES, AND PRIMARY HUMAN HEPATOCYTES. PROTEIN/MRNA EXPRESSION WERE MEASURED FOLLOWING TREATMENT WITH POLY(I:C), IFNALPHA AND HCV INFECTION. RESULTS: WHEN COMPARED TO HLCS, WE OBSERVED SEVERAL NOVEL ASPECTS OF THE ISGYLATION PATHWAY IN IPSCS. THESE INCLUDE A LOWER BASELINE EXPRESSION OF THE ISGYLATION-ACTIVATING ENZYME, UBE1L, A LACK OF IFN-INDUCED EXPRESSION OF THE ISGYLATION-CONJUGATION ENZYME UBE2L6, AN ATTENUATED ACTIVATION OF THE TRANSCRIPTION FACTOR STAT1 AND CONSTITUTIVE EXPRESSION OF SOCS1. ISGYLATION WAS OBSERVED IN IPSCS FOLLOWING DOWNREGULATION OF SOCS1, WHICH FACILITATED STAT1 ACTIVATION AND SUBSEQUENTLY INCREASED EXPRESSION OF UBE2L6. INTRIGUINGLY, HCV PERMISSIVE TRANSFORMED HEPATOMA CELL LINES DEMONSTRATED HIGHER INTRINSIC EXPRESSION OF SOCS1 AND WEAKER ISGYLATION FOLLOWING IFN TREATMENT. SOCS1 DOWNREGULATION IN HCV-INFECTED HUH 7.5.1 CELLS LED TO INCREASED ISGYLATION. CONCLUSIONS: HEREIN, WE SHOW THAT HIGH BASAL LEVELS OF SOCS1 INHIBIT STAT1 ACTIVATION AND SUBSEQUENTLY IFN-INDUCED UBE2L6 AND ISGYLATION IN IPSCS. FURTHERMORE, AS IPSCS DIFFERENTIATE INTO HEPATOCYTES, EPIGENETIC MECHANISMS REGULATE ISGYLATION BY MODIFYING UBE1L AND SOCS1 EXPRESSION LEVELS. OVERALL, THIS STUDY DEMONSTRATES THAT THE DEVELOPMENT OF CELL-INTRINSIC INNATE IMMUNITY DURING THE DIFFERENTIATION OF IPSCS TO HEPATOCYTES PROVIDES INSIGHT INTO CELL TYPE-SPECIFIC REGULATION OF HOST DEFENSE RESPONSES AND RELATED ONCOGENIC PROCESSES. IMPACT AND IMPLICATIONS: TO ELUCIDATE THE MECHANISM UNDERLYING REGULATION OF ISGYLATION, A KEY PROCESS IN THE INNATE IMMUNE RESPONSE, WE STUDIED CHANGES IN ISGYLATION-ASSOCIATED GENES AT THE DIFFERENT STAGES OF DIFFERENTIATION FROM IPSCS TO HEPATOCYTES. WE FOUND THAT HIGH BASAL LEVELS OF SOCS1 INHIBIT STAT1 ACTIVATION AND SUBSEQUENTLY IFN-INDUCED UBE2L6 AND ISGYLATION IN IPSCS. IMPORTANTLY, EPIGENETIC REGULATION OF SOCS1 AND SUBSEQUENTLY ISGYLATION MAY BE IMPORTANT FACTORS IN THE DEVELOPMENT OF CELL TYPE-SPECIFIC HOST DEFENSE RESPONSES IN HEPATOCYTES THAT SHOULD BE CONSIDERED WHEN STUDYING CHRONIC INFECTIONS AND ONCOGENIC PROCESSES IN THE LIVER. 2022 18 216 30 ACUTE BETA-ADRENERGIC ACTIVATION TRIGGERS NUCLEAR IMPORT OF HISTONE DEACETYLASE 5 AND DELAYS G(Q)-INDUCED TRANSCRIPTIONAL ACTIVATION. DURING HEMODYNAMIC STRESS, CATECHOLAMINES AND NEUROHUMORAL STIMULI MAY INDUCE CO-ACTIVATION OF G(Q)-COUPLED RECEPTORS AND BETA-ADRENERGIC RECEPTORS (BETA-AR), LEADING TO CARDIAC REMODELING. DYNAMIC REGULATION OF HISTONE DEACETYLASE 5 (HDAC5), A TRANSCRIPTIONAL REPRESSOR, IS CRUCIAL DURING STRESS SIGNALING DUE TO ITS ROLE IN EPIGENETIC CONTROL OF FETAL GENE MARKERS. LITTLE IS KNOWN ABOUT ITS REGULATION DURING ACUTE AND CHRONIC BETA-AR STIMULATION AND ITS CROSS-INTERACTION WITH G(Q) SIGNALING IN ADULT CARDIAC MYOCYTES. HERE, WE EVALUATE THE POTENTIAL CROSS-TALK BETWEEN G(Q)-DRIVEN AND BETA-AR MEDIATED SIGNALING AT THE LEVEL OF NUCLEOCYTOPLASMIC SHUTTLING OF HDAC5. WE SHOW THE TRANSLOCATION OF GFP-TAGGED WILD TYPE HDAC5 OR MUTANTS (S279A AND S279D) IN RESPONSE TO BETA-AR OR G(Q) AGONISTS. ISOPROTERENOL (ISO) OR PKA ACTIVATION RESULTS IN STRONG NUCLEAR ACCUMULATION OF HDAC5 IN CONTRAST TO NUCLEAR EXPORT DRIVEN BY CA(2+)-CALMODULIN PROTEIN KINASE II AND PROTEIN KINASE D. MOREOVER, NUCLEAR ACCUMULATION OF HDAC5 UNDER ACUTE ISO/PKA SIGNALING IS DEPENDENT ON PHOSPHORYLATION OF SER-279 AND CAN BLOCK SUBSEQUENT G(Q)-MEDIATED NUCLEAR HDAC5 EXPORT. INTRIGUINGLY, THE ATTENUATION OF G(Q)-INDUCED EXPORT IS ABOLISHED AFTER CHRONIC PKA ACTIVATION, YET NUCLEAR HDAC5 REMAINS ELEVATED. LAST, THE EFFECT OF CHRONIC BETA-AR SIGNALING ON HDAC5 TRANSLOCATION WAS EXAMINED IN ADULT MYOCYTES FROM A RABBIT MODEL OF HEART FAILURE, WHERE ISO-INDUCED NUCLEAR IMPORT IS ABLATED, BUT G(Q)-AGONIST MEDIATED EXPORT IS PRESERVED. ACUTE BETA-AR/PKA ACTIVATION PROTECTS AGAINST HYPERTROPHIC SIGNALING BY DELAYING G(Q)-MEDIATED TRANSCRIPTIONAL ACTIVATION. THIS SERVES AS A KEY PHYSIOLOGICAL CONTROL SWITCH BEFORE ALLOWING GENETIC REPROGRAMMING VIA HDAC5 NUCLEAR EXPORT DURING MORE SEVERE STRESS, SUCH AS HEART FAILURE. 2013 19 669 31 BONE MARROW STROMAL CELL ANTIGEN-1 (CD157) REGULATED BY SPHINGOSINE KINASE 2 MEDIATES KIDNEY FIBROSIS. CHRONIC KIDNEY DISEASE IS A PROGRESSIVE DISEASE THAT MAY LEAD TO END-STAGE RENAL DISEASE. INTERSTITIAL FIBROSIS DEVELOPS AS THE DISEASE PROGRESSES. THERAPIES THAT FOCUS ON FIBROSIS TO DELAY OR REVERSE PROGRESSIVE RENAL FAILURE ARE LIMITED. WE AND OTHERS SHOWED THAT SPHINGOSINE KINASE 2-DEFICIENT MICE (SPHK2 (-/-)) DEVELOP LESS FIBROSIS IN MOUSE MODELS OF KIDNEY FIBROSIS. SPHINGOSINE KINASE2 (SPHK2), ONE OF TWO SPHINGOSINE KINASES THAT PRODUCE SPHINGOSINE 1-PHOSPHATE (S1P), IS PRIMARILY LOCATED IN THE NUCLEUS. S1P PRODUCED BY SPHK2 INHIBITS HISTONE DEACETYLASE (HDAC) AND CHANGES HISTONE ACETYLATION STATUS, WHICH CAN LEAD TO ALTERED TARGET GENE EXPRESSION. WE HYPOTHESIZED THAT SPHK2 EPIGENETICALLY REGULATES DOWNSTREAM GENES TO INDUCE FIBROSIS, AND WE PERFORMED A COMPREHENSIVE ANALYSIS USING THE COMBINATION OF RNA-SEQ AND CHIP-SEQ. BST1/CD157 WAS IDENTIFIED AS A GENE THAT IS REGULATED BY SPHK2 THROUGH A CHANGE IN HISTONE ACETYLATION LEVEL, AND BST1 (-/-) MICE WERE FOUND TO DEVELOP LESS RENAL FIBROSIS AFTER UNILATERAL ISCHEMIA-REPERFUSION INJURY, A MOUSE MODEL OF KIDNEY FIBROSIS. ALTHOUGH BST1 IS A CELL-SURFACE MOLECULE THAT HAS A WIDE VARIETY OF FUNCTIONS THROUGH ITS VARIED ENZYMATIC ACTIVITIES AND DOWNSTREAM INTRACELLULAR SIGNALING PATHWAYS, NO STUDIES ON THE ROLE OF BST1 IN KIDNEY DISEASES HAVE BEEN REPORTED PREVIOUSLY. IN THE CURRENT STUDY, WE DEMONSTRATED THAT BST1 IS A GENE THAT IS REGULATED BY SPHK2 THROUGH EPIGENETIC CHANGE AND IS CRITICAL IN KIDNEY FIBROSIS. 2022 20 6659 26 UPREGULATION OF AKT3 CONFERS RESISTANCE TO THE AKT INHIBITOR MK2206 IN BREAST CANCER. ACQUIRED RESISTANCE TO MOLECULAR TARGETED THERAPY REPRESENTS A MAJOR CHALLENGE FOR THE EFFECTIVE TREATMENT OF CANCER. HYPERACTIVATION OF THE PI3K/AKT PATHWAY IS FREQUENTLY OBSERVED IN VIRTUALLY ALL HUMAN MALIGNANCIES, AND NUMEROUS PI3K AND AKT INHIBITORS ARE CURRENTLY UNDER CLINICAL EVALUATION. HOWEVER, MECHANISMS OF ACQUIRED RESISTANCE TO AKT INHIBITORS HAVE YET TO BE DESCRIBED. HERE, WE USE A BREAST CANCER PRECLINICAL MODEL TO IDENTIFY RESISTANCE MECHANISMS TO A SMALL MOLECULE ALLOSTERIC AKT INHIBITOR, MK2206. USING A STEP-WISE AND CHRONIC HIGH-DOSE EXPOSURE, BREAST CANCER CELL LINES HARBORING ONCOGENIC PI3K RESISTANT TO MK2206 WERE ESTABLISHED. USING THIS MODEL, WE REVEAL THAT AKT3 EXPRESSION IS MARKEDLY UPREGULATED IN AKT INHIBITOR-RESISTANT CELLS. INDUCTION OF AKT3 IS REGULATED EPIGENETICALLY BY THE BROMODOMAIN AND EXTRA TERMINAL DOMAIN PROTEINS. IMPORTANTLY, KNOCKDOWN OF AKT3, BUT NOT AKT1 OR AKT2, IN RESISTANT CELLS RESTORES SENSITIVITY TO MK2206. AKT INHIBITOR-RESISTANT CELLS ALSO DISPLAY AN EPITHELIAL TO MESENCHYMAL TRANSITION PHENOTYPE AS ASSESSED BY ALTERATIONS IN THE LEVELS OF E-CADHERIN, N-CADHERIN, AND VIMENTIN, AS WELL AS ENHANCED INVASIVENESS OF TUMOR SPHEROIDS. NOTABLY, THE INVASIVE MORPHOLOGY OF RESISTANT SPHEROIDS IS DIMINISHED UPON AKT3 DEPLETION. WE ALSO SHOW THAT RESISTANCE TO MK2206 IS REVERSIBLE BECAUSE UPON DRUG REMOVAL RESISTANT CELLS REGAIN SENSITIVITY TO AKT INHIBITION, ACCOMPANIED BY REEXPRESSION OF EPITHELIAL MARKERS AND REDUCTION OF AKT3 EXPRESSION, IMPLYING THAT EPIGENETIC REPROGRAMMING CONTRIBUTES TO ACQUISITION OF RESISTANCE. THESE FINDINGS PROVIDE A RATIONALE FOR DEVELOPING THERAPEUTICS TARGETING AKT3 TO CIRCUMVENT ACQUIRED RESISTANCE IN BREAST CANCER. MOL CANCER THER; 15(8); 1964-74. (C)2016 AACR. 2016