1 5301 101 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 2 1479 27 DIVERSE TARGETS OF THE TRANSCRIPTION FACTOR STAT3 CONTRIBUTE TO T CELL PATHOGENICITY AND HOMEOSTASIS. STAT3, AN ESSENTIAL TRANSCRIPTION FACTOR WITH PLEIOTROPIC FUNCTIONS, PLAYS CRITICAL ROLES IN THE PATHOGENESIS OF AUTOIMMUNITY. DESPITE RECENT DATA LINKING STAT3 WITH INFLAMMATORY BOWEL DISEASE, EXACTLY HOW IT CONTRIBUTES TO CHRONIC INTESTINAL INFLAMMATION IS NOT KNOWN. USING A T CELL TRANSFER MODEL OF COLITIS, WE FOUND THAT STAT3 EXPRESSION IN T CELLS WAS ESSENTIAL FOR THE INDUCTION OF BOTH COLITIS AND SYSTEMIC INFLAMMATION. STAT3 WAS CRITICAL IN MODULATING THE BALANCE OF T HELPER 17 (TH17) AND REGULATORY T (TREG) CELLS, AS WELL AS IN PROMOTING CD4(+) T CELL PROLIFERATION. WE USED CHROMATIN IMMUNOPRECIPITATION AND MASSIVE PARALLEL SEQUENCING (CHIP-SEQ) TO DEFINE THE GENOME-WIDE TARGETS OF STAT3 IN CD4(+) T CELLS. WE FOUND THAT STAT3 BOUND TO MULTIPLE GENES INVOLVED IN TH17 CELL DIFFERENTIATION, CELL ACTIVATION, PROLIFERATION, AND SURVIVAL, REGULATING BOTH EXPRESSION AND EPIGENETIC MODIFICATIONS. THUS, STAT3 ORCHESTRATES MULTIPLE CRITICAL ASPECTS OF T CELL FUNCTION IN INFLAMMATION AND HOMEOSTASIS. 2010 3 5592 26 ROLE OF TUMOR NECROSIS FACTOR-ALPHA IN THE HUMAN SYSTEMIC ENDOTOXIN-INDUCED TRANSCRIPTOME. TNFALPHA HAS BEEN IMPLICATED IN THE PATHOGENESIS OF VARIOUS INFLAMMATORY DISEASES. DIFFERENT STRATEGIES TO INHIBIT TNFALPHA IN PATIENTS WITH SEPSIS AND CHRONIC INFLAMMATORY CONDITIONS HAVE SHOWN CONTRASTING OUTCOMES. ALTHOUGH TNFALPHA INHIBITORS ARE WIDELY USED IN CLINICAL PRACTICE, THE IMPACT OF TNFALPHA ANTAGONISM ON WHITE BLOOD CELL GENE EXPRESSION PROFILES DURING ACUTE INFLAMMATION IN HUMANS IN VIVO HAS NOT BEEN ASSESSED. WE HERE LEVERAGED THE ESTABLISHED MODEL OF HUMAN ENDOTOXEMIA TO EXAMINE THE EFFECT OF THE TNFALPHA ANTAGONIST, ETANERCEPT, ON THE GENOME-WIDE TRANSCRIPTIONAL RESPONSES IN CIRCULATING LEUKOCYTES INDUCED BY INTRAVENOUS LPS ADMINISTRATION IN MALE SUBJECTS. ETANERCEPT PRE-TREATMENT RESULTED IN A MARKEDLY DAMPENED TRANSCRIPTIONAL RESPONSE TO LPS. GENE CO-EXPRESSION NETWORK ANALYSIS REVEALED THIS LPS-INDUCED TRANSCRIPTOME CAN BE CATEGORIZED AS TNFALPHA RESPONSIVE AND NON-RESPONSIVE MODULES. HIGHLY SIGNIFICANT TNFALPHA RESPONSIVE MODULES INCLUDE NF-KB SIGNALING, ANTIVIRAL RESPONSES AND T-CELL MEDIATED RESPONSES. WITHIN THESE TNFALPHA RESPONSIVE MODULES WE DELINEATE FUNDAMENTAL GENES INVOLVED IN EPIGENETIC MODIFICATIONS, TRANSCRIPTIONAL INITIATION AND ELONGATION. THUS, WE PROVIDE COMPREHENSIVE INFORMATION ABOUT MOLECULAR PATHWAYS THAT MIGHT BE TARGETED BY THERAPEUTIC INTERVENTIONS THAT SEEK TO INHIBIT TNFALPHA ACTIVITY DURING HUMAN INFLAMMATORY DISEASES. 2013 4 2380 27 EPIGENETIC REGULATION OF WNT SIGNALING IN CHRONIC LYMPHOCYTIC LEUKEMIA. CERTAIN WNT AND WNT NETWORK TARGET GENES ARE EXPRESSED AT HIGHER OR LOWER LEVELS IN CHRONIC LYMPHOCYTIC LEUKEMIA COMPARED WITH NORMAL B-CELLS. THIS INCLUDES UPREGULATION OF NUCLEAR COMPLEX GENES, AS WELL AS GENES FOR CYTOPLASMIC PROTEINS AND WNT LIGANDS AND THEIR COGNATE RECEPTORS. IN ADDITION, EPIGENETIC SILENCING OF SEVERAL NEGATIVE REGULATORS OF THE WNT PATHWAY HAVE BEEN IDENTIFIED. THE BALANCE BETWEEN EPIGENETIC DOWNREGULATION OF NEGATIVE EFFECTOR GENES AND INCREASED EXPRESSION OF POSITIVE EFFECTOR GENES DEMONSTRATE THAT THE EPIGENETIC DOWNREGULATION OF WNT ANTAGONISTS IS ONE MECHANISM, PERHAPS THE MAIN MECHANISM, THAT IS PERMISSIVE TO ACTIVE WNT SIGNALING IN CHRONIC LYMPHOCYTIC LEUKEMIA. MOREOVER, CONSTITUTIVE ACTIVATION OF THE WNT NETWORK AND TARGET GENES IS LIKELY TO IMPACT ON ADDITIONAL INTERACTING SIGNALING PATHWAYS. BASED ON PUBLISHED STUDIES, WE PROPOSE A MODEL OF WNT SIGNALING THAT INVOLVES MAINLY PERMISSIVE EXPRESSION, AND SOMETIMES OVEREXPRESSION, OF POSITIVE EFFECTORS AND DOWNREGULATION OF NEGATIVE REGULATORS IN THE NETWORK. IN THIS MODEL, DNA METHYLATION, HISTONE MODIFICATIONS AND ALTERED EXPRESSION OF MICRORNA MOLECULES INTERACT TO ALLOW CONTINUOUS WNT SIGNALING. 2010 5 5795 24 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 5975 24 TET1 IS AN IMPORTANT TRANSCRIPTIONAL ACTIVATOR OF TNFALPHA EXPRESSION IN MACROPHAGES. ACTIVATION OF MACROPHAGES AND OVEREXPRESSION OF TNFALPHA IS ASSOCIATED WITH THE PATHOGENESIS OF CHRONIC INFLAMMATORY DISEASES. HOWEVER, THE MECHANISMS LEADING TO TNFALPHA OVEREXPRESSION ARE STILL UNKNOWN. 5-METHYLOCYTOSINE (5-MC) IS AN EPIGENETIC MODIFICATION THAT IS ASSOCIATED WITH SILENCED GENES. RECENT STUDIES SHOWED THAT IT IS CONVERTED TO 5-HYDROXYLMETHYLOCYTOSINE (5-HMC) AND REACTIVATES GENE EXPRESSION THROUGH THE ACTION OF THE FAMILY OF TEN-ELEVEN-TRANSLOCATION (TET1-3) ENZYMES. IN THIS STUDY, WE SHOW THAT 5-HMC LEVELS ARE INCREASED GLOBALLY AND SPECIFICALLY IN THE TNFALPHA PROMOTER DURING THE DIFFERENTIATION OF MONOCYTES TO MACROPHAGES. IN ADDITION, THE LEVELS OF 5-HMC ARE INCREASED UPON LPS STIMULATION OF MACROPHAGES. FURTHERMORE, CRIPSR STABLE KNOCKOUT OF TET1 DECREASES THE EXPRESSION OF TNFALPHA AND OTHER PRO-INFLAMMATORY CYTOKINES. IN CONCLUSION, WE SHOWED THAT TET1 CONTRIBUTES TO THE ACTIVATION OF MACROPHAGES POSSIBLY THROUGH REGULATION OF 5-HYDROXYMETHYLATION IN THE PROMOTER OF PRO-INFLAMMATORY CYTOKINE GENES. THE TET1 ENZYME COULD BE A PROMISING THERAPEUTIC TARGET TO INHIBIT THE PERSISTENT INFLAMMATION CAUSED BY MACROPHAGES IN CHRONIC INFLAMMATORY DISEASES. 2019 7 3527 25 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 8 4284 22 MICRORNA CIRCUITS REGULATE THE CANCER-INFLAMMATION LINK. GENETIC AND EPIGENETIC PERTURBATIONS ARE REQUIRED TO TRANSFORM NORMAL CELLS INTO CANCER CELLS. INFLAMMATORY SIGNALING PATHWAYS ARE ACTIVATED IN VARIOUS CANCERS, LINKING CHRONIC INFLAMMATION TO ONCOGENESIS. HOWEVER, THE MOLECULAR CIRCUITS THAT RESULT IN SUSTAINED ACTIVATION OF THESE INFLAMMATORY FACTORS ARE NOT YET WELL UNDERSTOOD. IN THE 28 JANUARY 2014 ISSUE OF SCIENCE SIGNALING, XIANG ET AL. IDENTIFIED A MICRORNA-MEDIATED ANTI-INFLAMMATORY CIRCUIT THAT IS REPRESSED EPIGENETICALLY IN RECEPTOR-NEGATIVE BREAST CANCERS. A HIGH-THROUGHPUT SCREEN FOR SIGNAL TRANSDUCER AND ACTIVATOR OF TRANSCRIPTION 3 (STAT3)-REGULATED MICRORNAS REVEALED MICRORNA MIR-146B AS A DIRECT STAT3 TARGET IN MAMMARY EPITHELIAL CELLS, BUT DNA METHYLATION IN ITS PROMOTER AREA SUPPRESSED MIR-146B EXPRESSION IN CANCER CELLS. OVEREXPRESSION OF MIR-146B SUPPRESSED NUCLEAR FACTOR KAPPAB (NF-KAPPAB)-DEPENDENT EXPRESSION OF IL6 AND SUBSEQUENT STAT3 ACTIVATION AND DECREASED THE STAT3-INDUCED INVASIVENESS AND MESENCHYMAL PHENOTYPE OF BREAST CANCER CELLS. OVERALL, THIS STUDY CONTRIBUTES TO OUR UNDERSTANDING OF HOW INFLAMMATION IS INVOLVED IN ONCOGENIC TRANSFORMATION. FURTHER STUDIES COULD EVALUATE THE THERAPEUTIC POTENTIAL OF TARGETING THIS CIRCUIT IN ESTROGEN RECEPTOR-NEGATIVE BREAST CANCERS. 2014 9 911 29 CHRONIC EXPOSURE TO TNF REPROGRAMS CELL SIGNALING PATHWAYS IN FIBROBLAST-LIKE SYNOVIOCYTES BY ESTABLISHING LONG-TERM INFLAMMATORY MEMORY. FIBROBLAST-LIKE SYNOVIOCYTES (FLS) PLAY A CRITICAL ROLE IN THE PATHOGENESIS OF RHEUMATOID ARTHRITIS (RA). CHRONIC INFLAMMATION INDUCES TRANSCRIPTOMIC AND EPIGENETIC MODIFICATIONS THAT IMPARTS A PERSISTENT CATABOLIC PHENOTYPE TO THE FLS, DESPITE THEIR DISSOCIATION FROM THE INFLAMMATORY ENVIRONMENT. WE ANALYZED HIGH THROUGHPUT GENE EXPRESSION AND CHROMATIN ACCESSIBILITY DATA FROM HUMAN AND MOUSE FLS FROM OUR AND OTHER STUDIES AVAILABLE ON PUBLIC REPOSITORIES, WITH THE GOAL OF IDENTIFYING THE PERSISTENTLY REPROGRAMMED SIGNALING PATHWAYS DRIVEN BY CHRONIC INFLAMMATION. WE FOUND THAT THE GENE EXPRESSION CHANGES INDUCED BY SHORT-TERM TUMOR NECROSIS FACTOR-ALPHA (TNF) TREATMENT WERE LARGELY SUSTAINED IN THE FLS EXPOSED TO CHRONIC INFLAMMATION. THESE CHANGES THAT INCLUDED BOTH ACTIVATION AND REPRESSION OF GENE EXPRESSION, WERE ACCOMPANIED BY THE REMODELING OF CHROMATIN ACCESSIBILITY. THE SUSTAINED ACTIVATED GENES (SAGS) INCLUDED ESTABLISHED PRO-INFLAMMATORY SIGNALING COMPONENTS KNOWN TO ACT AT MULTIPLE LEVELS OF NF-KAPPAB, STAT AND AP-1 SIGNALING CASCADES. INTERESTINGLY, THE SUSTAINED REPRESSED GENES (SRGS) INCLUDED CRITICAL MEDIATORS AND TARGETS OF THE BMP SIGNALING PATHWAY. WE THUS IDENTIFIED SUSTAINED REPRESSION OF BMP SIGNALING AS A UNIQUE CONSTITUENT OF THE LONG-TERM INFLAMMATORY MEMORY INDUCED BY CHRONIC INFLAMMATION. WE POSTULATE THAT SIMULTANEOUS TARGETING OF THESE ACTIVATED AND REPRESSED SIGNALING PATHWAYS MAY BE NECESSARY TO COMBAT RA PERSISTENCE. 2020 10 3795 24 INTERLEUKIN-6 CONTRIBUTES TO GROWTH IN CHOLANGIOCARCINOMA CELLS BY ABERRANT PROMOTER METHYLATION AND GENE EXPRESSION. THE ASSOCIATION BETWEEN CHRONIC INFLAMMATION AND THE DEVELOPMENT AND PROGRESSION OF MALIGNANCY IS EXEMPLIFIED IN THE BILIARY TRACT WHERE PERSISTENT INFLAMMATION STRONGLY PREDISPOSES TO CHOLANGIOCARCINOMA. THE INFLAMMATORY CYTOKINE INTERLEUKIN-6 (IL-6) ENHANCES TUMOR GROWTH IN CHOLANGIOCARCINOMA BY ALTERED GENE EXPRESSION VIA AUTOCRINE MECHANISMS. IL-6 CAN REGULATE THE ACTIVITY OF DNA METHYLTRANSFERASES, AND MOREOVER, ABERRANT DNA METHYLATION CAN CONTRIBUTE TO CARCINOGENESIS. WE THEREFORE INVESTIGATED THE EFFECT OF CHRONIC EXPOSURE TO IL-6 ON METHYLATION-DEPENDENT GENE EXPRESSION AND TRANSFORMED CELL GROWTH IN HUMAN CHOLANGIOCARCINOMA. THE RELATIONSHIP BETWEEN AUTOCRINE IL-6 PATHWAYS, DNA METHYLATION, AND TRANSFORMED CELL GROWTH WAS ASSESSED USING MALIGNANT CHOLANGIOCYTES STABLY TRANSFECTED TO OVEREXPRESS IL-6. TREATMENT WITH THE DNA METHYLATION INHIBITOR 5-AZA-2'-DEOXYCYTIDINE DECREASED CELL PROLIFERATION, GROWTH IN SOFT AGAR, AND METHYLCYTOSINE CONTENT OF MALIGNANT CHOLANGIOCYTES. HOWEVER, THIS EFFECT WAS NOT OBSERVED IN IL-6-OVEREXPRESSING CELLS. IL-6 OVEREXPRESSION RESULTED IN THE ALTERED EXPRESSION AND PROMOTER METHYLATION OF SEVERAL GENES, INCLUDING THE EPIDERMAL GROWTH FACTOR RECEPTOR (EGFR). EGFR PROMOTER METHYLATION WAS DECREASED AND GENE AND PROTEIN EXPRESSION WAS INCREASED BY IL-6. THUS, EPIGENETIC REGULATION OF GENE EXPRESSION BY IL-6 CAN CONTRIBUTE TO TUMOR PROGRESSION BY ALTERING PROMOTER METHYLATION AND GENE EXPRESSION OF GROWTH-REGULATORY PATHWAYS, SUCH AS THOSE INVOLVING EGFR. MOREOVER, ENHANCED IL-6 EXPRESSION MAY DECREASE THE SENSITIVITY OF TUMOR CELLS TO THERAPEUTIC TREATMENTS USING METHYLATION INHIBITORS. THESE OBSERVATIONS HAVE IMPORTANT IMPLICATIONS FOR CANCER TREATMENT AND PROVIDE A MECHANISM BY WHICH PERSISTENT CYTOKINE STIMULATION CAN PROMOTE TUMOR GROWTH. 2006 11 2067 26 EPIGENETIC CONTROL OF MACROPHAGE SHAPE TRANSITION TOWARDS AN ATYPICAL ELONGATED PHENOTYPE BY HISTONE DEACETYLASE ACTIVITY. INFLAMMATORY CHRONIC PATHOLOGIES ARE COMPLEX PROCESSES CHARACTERIZED BY AN IMBALANCE BETWEEN THE RESOLUTION OF THE INFLAMMATORY PHASE AND THE ESTABLISHMENT OF TISSUE REPAIR. THE MAIN PLAYERS IN THESE INFLAMMATORY PATHOLOGIES ARE BONE MARROW DERIVED MONOCYTES (BMDMS). HOWEVER, HOW MONOCYTE DIFFERENTIATION IS MODULATED TO GIVE RISE TO SPECIFIC MACROPHAGE SUBPOPULATIONS (M1 OR M2) THAT MAY EITHER MAINTAIN THE CHRONIC INFLAMMATORY PROCESS OR LEAD TO WOUND HEALING IS STILL UNCLEAR. CONSIDERING THAT INHIBITORS OF HISTONE DEACETYLASE (HDAC) HAVE AN ANTI-INFLAMMATORY ACTIVITY, WE ASKED WHETHER THIS ENZYME WOULD PLAY A ROLE ON MONOCYTE DIFFERENTIATION INTO M1 OR M2 PHENOTYPE AND IN THE CELL SHAPE TRANSITION THAT FOLLOWS. WE THEN INDUCED MURINE BONE MARROW PROGENITORS INTO MONOCYTE/MACROPHAGE DIFFERENTIATION PATHWAY USING MEDIA CONTAINING GM-CSF AND THE HDAC BLOCKER, TRICHOSTATIN A (TSA). WE FOUND THAT THE PHARMACOLOGICAL INHIBITION OF HDAC ACTIVITY LED TO A SHAPE TRANSITION FROM THE TYPICAL MACROPHAGE PANCAKE-LIKE SHAPE INTO AN ELONGATED MORPHOLOGY, WHICH WAS CORRELATED TO A MIXED M1/M2 PROFILE OF CYTOKINE AND CHEMOKINE SECRETION. OUR RESULTS PRESENT, FOR THE FIRST TIME, THAT HDAC ACTIVITY ACTS AS A REGULATOR OF MACROPHAGE DIFFERENTIATION IN THE ABSENCE OF LYMPHOCYTE STIMULI. WE PROPOSE THAT HDAC ACTIVITY DOWN REGULATES MACROPHAGE PLASTICITY FAVORING THE PRO-INFLAMMATORY PHENOTYPE. 2015 12 2228 21 EPIGENETIC MODIFICATIONS OF HISTONES IN PERIODONTAL DISEASE. PERIODONTITIS IS A CHRONIC INFECTIOUS DISEASE DRIVEN BY DYSBIOSIS, AN IMBALANCE BETWEEN COMMENSAL BACTERIA AND THE HOST ORGANISM. PERIODONTITIS IS A LEADING CAUSE OF TOOTH LOSS IN ADULTS AND OCCURS IN ABOUT 50% OF THE US POPULATION. IN ADDITION TO THE CLINICAL CHALLENGES ASSOCIATED WITH TREATING PERIODONTITIS, THE PROGRESSION AND CHRONIC NATURE OF THIS DISEASE SERIOUSLY AFFECT HUMAN HEALTH. EMERGING EVIDENCE SUGGESTS THAT PERIODONTITIS IS ASSOCIATED WITH MECHANISMS BEYOND BACTERIA-INDUCED PROTEIN AND TISSUE DEGRADATION. HERE, WE HYPOTHESIZE THAT BACTERIA ARE ABLE TO INDUCE EPIGENETIC MODIFICATIONS IN ORAL EPITHELIAL CELLS MEDIATED BY HISTONE MODIFICATIONS. IN THIS STUDY, WE FOUND THAT DYSBIOSIS IN VIVO LED TO EPIGENETIC MODIFICATIONS, INCLUDING ACETYLATION OF HISTONES AND DOWNREGULATION OF DNA METHYLTRANSFERASE 1. IN ADDITION, IN VITRO EXPOSURE OF ORAL EPITHELIAL CELLS TO LIPOPOLYSACCHARIDES RESULTED IN HISTONE MODIFICATIONS, ACTIVATION OF TRANSCRIPTIONAL COACTIVATORS, SUCH AS P300/CBP, AND ACCUMULATION OF NUCLEAR FACTOR-KAPPAB (NF-KAPPAB). GIVEN THAT ORAL EPITHELIAL CELLS ARE THE FIRST LINE OF DEFENSE FOR THE PERIODONTIUM AGAINST BACTERIA, WE ALSO EVALUATED WHETHER ACTIVATION OF PATHOGEN RECOGNITION RECEPTORS INDUCED HISTONE MODIFICATIONS. WE FOUND THAT ACTIVATION OF THE TOLL-LIKE RECEPTORS 1, 2, AND 4 AND THE NUCLEOTIDE-BINDING OLIGOMERIZATION DOMAIN PROTEIN 1 INDUCED HISTONE ACETYLATION IN ORAL EPITHELIAL CELLS. OUR FINDINGS CORROBORATE THE EMERGING CONCEPT THAT EPIGENETIC MODIFICATIONS PLAY A ROLE IN THE DEVELOPMENT OF PERIODONTITIS. 2016 13 926 23 CHRONIC INFLAMMATION PATHWAY NF-KAPPAB COOPERATES WITH EPIGENETIC REPROGRAMMING TO DRIVE THE MALIGNANT PROGRESSION OF GLIOBLASTOMA. WITHOUT AN EFFECTIVE STRATEGY FOR TARGETED THERAPY, GLIOBLASTOMA IS STILL INCURABLE WITH A MEDIAN SURVIVAL OF ONLY 15 MONTHS. BOTH CHRONIC INFLAMMATION AND EPIGENETIC REPROGRAMMING ARE HALLMARKS OF CANCER. HOWEVER, THE MECHANISMS AND CONSEQUENCES OF THEIR COOPERATION IN GLIOBLASTOMA REMAIN UNKNOWN. HERE, WE DISCOVER THAT CHRONIC INFLAMMATION GOVERNS H3K27ME3 REPROGRAMMING IN GLIOBLASTOMA THROUGH THE CANONICAL NF-KAPPAB PATHWAY TO TARGET EZH2. BEING A CRUCIAL MEDIATOR OF CHRONIC INFLAMMATION, THE CANONICAL NF-KAPPAB SIGNALLING SPECIFICALLY DIRECTS THE EXPRESSION AND REDISTRIBUTION OF H3K27ME3 BUT NOT H3K4ME3, H3K9ME3 AND H3K36ME3. USING RNA-SEQ SCREENING TO FOCUS ON GENES ENCODING METHYLTRANSFERASES AND DEMETHYLASES OF HISTONE, WE IDENTIFY EZH2 AS A KEY METHYLTRANSFERASE TO CONTROL INFLAMMATION-TRIGGERED EPIGENETIC REPROGRAMMING IN GLIOMAGENESIS. MECHANISTICALLY, NF-KAPPAB SELECTIVELY DRIVES THE EXPRESSION OF EZH2 BY ACTIVATING ITS TRANSCRIPTION, CONSEQUENTLY RESULTING IN A GLOBAL CHANGE IN H3K27ME3 EXPRESSION AND DISTRIBUTION. FURTHERMORE, WE FIND THAT CO-ACTIVATION OF NF-KAPPAB AND EZH2 CONFERS THE POOREST CLINICAL OUTCOME, AND THAT THE RISK FOR GLIOBLASTOMA CAN BE ACCURATELY MOLECULARLY STRATIFIED BY NF-KAPPAB AND EZH2. IT IS NOTABLE THAT NF-KAPPAB CAN POTENTIALLY COOPERATE WITH EZH2 IN MORE THAN ONE WAY, AND MOST IMPORTANTLY, WE DEMONSTRATE A SYNERGISTIC EFFECT OF CANCER CELLS INDUCED BY COMBINATORY INHIBITION OF NF-KAPPAB AND EZH2, WHICH BOTH ARE FREQUENTLY OVER-ACTIVATED IN GLIOBLASTOMA. IN SUMMARY, WE UNCOVER A FUNCTIONAL COOPERATION BETWEEN CHRONIC INFLAMMATION AND EPIGENETIC REPROGRAMMING IN GLIOBLASTOMA, COMBINED TARGETING OF WHICH BY INHIBITORS GUARANTEED IN SAFETY AND AVAILABILITY FURNISHES A POTENT STRATEGY FOR EFFECTIVE TREATMENT OF THIS FATAL DISEASE. 2022 14 2493 32 EPIGENETICS AND CHROMATIN REMODELING PLAY A ROLE IN LUNG DISEASE. EPIGENETICS IS DEFINED AS HERITABLE CHANGES THAT AFFECT GENE EXPRESSION WITHOUT ALTERING THE DNA SEQUENCE. EPIGENETIC REGULATION OF GENE EXPRESSION IS FACILITATED THROUGH DIFFERENT MECHANISMS SUCH AS DNA METHYLATION, HISTONE MODIFICATIONS AND RNA-ASSOCIATED SILENCING BY SMALL NON-CODING RNAS. ALL THESE MECHANISMS ARE CRUCIAL FOR NORMAL DEVELOPMENT, DIFFERENTIATION AND TISSUE-SPECIFIC GENE EXPRESSION. THESE THREE SYSTEMS INTERACT AND STABILIZE ONE ANOTHER AND CAN INITIATE AND SUSTAIN EPIGENETIC SILENCING, THUS DETERMINING HERITABLE CHANGES IN GENE EXPRESSION. HISTONE ACETYLATION REGULATES DIVERSE CELLULAR FUNCTIONS INCLUDING INFLAMMATORY GENE EXPRESSION, DNA REPAIR AND CELL PROLIFERATION. TRANSCRIPTIONAL COACTIVATORS POSSESS INTRINSIC HISTONE ACETYLTRANSFERASE ACTIVITY AND THIS ACTIVITY DRIVES INFLAMMATORY GENE EXPRESSION. ELEVEN CLASSICAL HISTONE DEACETYLASES (HDACS) ACT TO REGULATE THE EXPRESSION OF DISTINCT SUBSETS OF INFLAMMATORY/IMMUNE GENES. THUS, LOSS OF HDAC ACTIVITY OR THE PRESENCE OF HDAC INHIBITORS CAN FURTHER ENHANCE INFLAMMATORY GENE EXPRESSION BY PRODUCING A GENE-SPECIFIC CHANGE IN HAT ACTIVITY. FOR EXAMPLE, HDAC2 EXPRESSION AND ACTIVITY ARE REDUCED IN LUNG MACROPHAGES, BIOPSY SPECIMENS, AND BLOOD CELLS FROM PATIENTS WITH SEVERE ASTHMA AND SMOKING ASTHMATICS, AS WELL AS IN PATIENTS WITH CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD). THIS MAY ACCOUNT, AT LEAST IN PART, FOR THE ENHANCED INFLAMMATION AND REDUCED STEROID RESPONSIVENESS SEEN IN THESE PATIENTS. OTHER PROTEINS, PARTICULARLY TRANSCRIPTION FACTORS, ARE ALSO ACETYLATED AND ARE TARGETS FOR DEACETYLATION BY HDACS AND SIRTUINS, A RELATED FAMILY OF 7 PREDOMINANTLY PROTEIN DEACETYLASES. THUS THE ACETYLATION/DEACETYLATION STATUS OF NF-KAPPAB AND THE GLUCOCORTICOID RECEPTOR CAN ALSO AFFECT THE OVERALL EXPRESSION PATTERN OF INFLAMMATORY GENES AND REGULATE THE INFLAMMATORY RESPONSE. UNDERSTANDING AND TARGETING SPECIFIC ENZYMES INVOLVED IN THIS PROCESS MIGHT LEAD TO NEW THERAPEUTIC AGENTS, PARTICULARLY IN SITUATIONS IN WHICH CURRENT ANTI-INFLAMMATORY THERAPIES ARE SUBOPTIMAL. 2011 15 2055 21 EPIGENETIC CONTROL DURING LYMPHOID DEVELOPMENT AND IMMUNE RESPONSES: ABERRANT REGULATION, VIRUSES, AND CANCER. METHYLATION OF CYTOSINES CONTROLS A NUMBER OF BIOLOGIC PROCESSES SUCH AS IMPRINTING AND X CHROMOSOMAL INACTIVATION. DNA HYPERMETHYLATION IS CLOSELY ASSOCIATED WITH TRANSCRIPTIONAL SILENCING, WHILE DNA HYPOMETHYLATION IS ASSOCIATED WITH TRANSCRIPTIONAL ACTIVATION. HYPOACETYLATION OF HISTONES LEADS TO COMPACT CHROMATIN WITH REDUCED ACCESSIBILITY TO THE TRANSCRIPTIONAL MACHINERY. METHYL-CPG BINDING PROTEINS CAN RECRUIT COREPRESSORS AND HISTONE DEACETYLASES; THUS, THE INTERPLAY BETWEEN THESE EPIGENETIC MECHANISMS REGULATES GENE ACTIVATION. METHYLATION HAS BEEN IMPLICATED AS AN IMPORTANT MECHANISM DURING IMMUNE DEVELOPMENT, CONTROLLING VDJ RECOMBINATION, LINEAGE-SPECIFIC EXPRESSION OF CELL SURFACE ANTIGENS, AND TRANSCRIPTIONAL REGULATION OF CYTOKINE GENES DURING IMMUNE RESPONSES. ABERRATIONS IN EPIGENETIC MACHINERY, EITHER BY GENETIC MUTATIONS OR BY SOMATIC CHANGES SUCH AS VIRAL INFECTIONS, ARE ASSOCIATED WITH EARLY ALTERATIONS IN CHRONIC DISEASES SUCH AS IMMUNODEFICIENCY AND CANCER. 2003 16 1336 19 DESCRIBING A TRANSCRIPTION FACTOR DEPENDENT REGULATION OF THE MICRORNA TRANSCRIPTOME. WHILE THE TRANSCRIPTION REGULATION OF PROTEIN CODING GENES WAS EXTENSIVELY STUDIED, LITTLE IS KNOWN ON HOW TRANSCRIPTION FACTORS ARE INVOLVED IN TRANSCRIPTION OF NON-CODING RNAS, SPECIFICALLY OF MICRORNAS. HERE, WE PROPOSE A STRATEGY TO STUDY THE POTENTIAL ROLE OF TRANSCRIPTION FACTOR IN REGULATING TRANSCRIPTION OF MICRORNAS USING PUBLICALLY AVAILABLE DATA, COMPUTATIONAL RESOURCES AND HIGH THROUGHPUT DATA. WE USE THE H3K4ME3 EPIGENETIC SIGNATURE TO IDENTIFY MICRORNA PROMOTERS AND CHROMATIN IMMUNOPRECIPITATION (CHIP)-SEQUENCING DATA FROM THE ENCODE PROJECT TO IDENTIFY MICRORNA PROMOTERS THAT ARE ENRICHED WITH TRANSCRIPTION FACTOR BINDING SITES. BY TRANSFECTING CELLS OF INTEREST WITH SHRNA TARGETING A TRANSCRIPTION FACTOR OF INTEREST AND SUBJECTING THE CELLS TO MICRORNA ARRAY, WE STUDY THE EFFECT OF THIS TRANSCRIPTION FACTOR ON THE MICRORNA TRANSCRIPTOME. AS AN ILLUSTRATIVE EXAMPLE WE USE OUR STUDY ON THE EFFECT OF STAT3 ON THE MICRORNA TRANSCRIPTOME OF CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) CELLS. 2016 17 3276 28 HEPATOCYTE GROWTH CONTROL BY SOCS1 AND SOCS3. THE EXTRAORDINARY CAPACITY OF THE LIVER TO REGENERATE FOLLOWING INJURY IS DEPENDENT ON COORDINATED AND REGULATED ACTIONS OF CYTOKINES AND GROWTH FACTORS. WHEREAS HEPATOCYTE GROWTH FACTOR (HGF) AND EPIDERMAL GROWTH FACTOR (EGF) ARE DIRECT MITOGENS TO HEPATOCYTES, INFLAMMATORY CYTOKINES SUCH AS TNFALPHA AND IL-6 ALSO PLAY ESSENTIAL ROLES IN THE LIVER REGENERATION PROCESS. THESE CYTOKINES AND GROWTH FACTORS ACTIVATE DIFFERENT SIGNALING PATHWAYS IN A SEQUENTIAL MANNER TO ELICIT HEPATOCYTE PROLIFERATION. THE KINETICS AND MAGNITUDE OF THESE HEPATOCYTE-ACTIVATING STIMULI ARE TIGHTLY REGULATED TO ENSURE RESTORATION OF A FUNCTIONAL LIVER MASS WITHOUT CAUSING UNCONTROLLED CELL PROLIFERATION. HEPATOCYTE PROLIFERATION CAN BECOME DEREGULATED UNDER CONDITIONS OF CHRONIC INFLAMMATION, LEADING TO ACCUMULATION OF GENETIC ABERRATIONS AND EVENTUAL NEOPLASTIC TRANSFORMATION. AMONG THE CONTROL MECHANISMS THAT REGULATE HEPATOCYTE PROLIFERATION, NEGATIVE FEEDBACK INHIBITION BY THE 'SUPPRESSOR OF CYTOKINE SIGNALING (SOCS)' FAMILY PROTEINS SOCS1 AND SOCS3 PLAY CRUCIAL ROLES IN ATTENUATING CYTOKINE AND GROWTH FACTOR SIGNALING. LOSS OF SOCS1 OR SOCS3 IN THE MOUSE LIVER INCREASES THE RATE OF LIVER REGENERATION AND RENDERS HEPATOCYTES SUSCEPTIBLE TO NEOPLASTIC TRANSFORMATION. THE FREQUENT EPIGENETIC REPRESSION OF THE SOCS1 AND SOCS3 GENES IN HEPATOCELLULAR CARCINOMA HAS STIMULATED RESEARCH IN UNDERSTANDING THE GROWTH REGULATORY MECHANISMS OF SOCS1 AND SOCS3 IN HEPATOCYTES. WHEREAS SOCS3 IS IMPLICATED IN REGULATING JAK-STAT SIGNALING INDUCED BY IL-6 AND ATTENUATING EGFR SIGNALING, SOCS1 IS CRUCIAL FOR THE REGULATION OF HGF SIGNALING. THESE TWO PROTEINS ALSO MODULE THE FUNCTIONS OF CERTAIN KEY PROTEINS THAT CONTROL THE CELL CYCLE. IN THIS REVIEW, WE DISCUSS THE CURRENT UNDERSTANDING OF THE FUNCTIONS OF SOCS1 AND SOCS3 IN CONTROLLING HEPATOCYTE PROLIFERATION, AND ITS IMPLICATIONS TO LIVER HEALTH AND DISEASE. 2019 18 4695 26 NF-KAPPAB ACTIVATION IN CHRONIC LYMPHOCYTIC LEUKEMIA: A POINT OF CONVERGENCE OF EXTERNAL TRIGGERS AND INTRINSIC LESIONS. THE NUCLEAR FACTOR-KAPPAB (NF-KAPPAB) PATHWAY IS CONSTITUTIVELY ACTIVATED IN CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) PATIENTS, AND HENCE PLAYS A MAJOR ROLE IN DISEASE DEVELOPMENT AND EVOLUTION. IN CONTRAST TO MANY OTHER MATURE B-CELL LYMPHOMAS, ONLY A FEW RECURRENTLY MUTATED GENES INVOLVED IN CANONICAL OR NON-CANONICAL NF-KAPPAB ACTIVATION HAVE BEEN IDENTIFIED IN CLL (I.E. BIRC3, MYD88 AND NFKBIE MUTATIONS) AND OFTEN AT A LOW FREQUENCY. ON THE OTHER HAND, CLL B CELLS SEEM 'ADDICTED' TO THE TUMOR MICROENVIRONMENT FOR THEIR SURVIVAL AND PROLIFERATION, WHICH IS PRIMARILY MEDIATED BY INTERACTION THROUGH A NUMBER OF CELL SURFACE RECEPTORS, E.G. THE B-CELL RECEPTOR (BCR), TOLL-LIKE RECEPTORS AND CD40, THAT IN TURN ACTIVATE DOWNSTREAM NF-KAPPAB. THE IMPORTANCE OF CELL-EXTRINSIC TRIGGERING FOR CLL PATHOPHYSIOLOGY WAS RECENTLY ALSO HIGHLIGHTED BY THE CLINICAL EFFICACY OF NOVEL DRUGS TARGETING MICROENVIRONMENTAL INTERACTIONS THROUGH THE INHIBITION OF BCR SIGNALING. IN OTHER WORDS, CLL CAN BE CONSIDERED A PROTOTYPE DISEASE FOR STUDYING THE INTRICATE INTERPLAY BETWEEN EXTERNAL TRIGGERS AND INTRINSIC ABERRATIONS AND THEIR COMBINED IMPACT ON DISEASE EVOLUTION. IN THIS REVIEW, WE WILL DISCUSS THE CURRENT UNDERSTANDING OF MECHANISMS UNDERLYING NF-KAPPAB DEREGULATION IN CLL, INCLUDING MICRO-ENVIRONMENTAL, GENETIC AND EPIGENETIC EVENTS, AND SUMMARIZE DATA GENERATED IN MURINE MODELS RESEMBLING HUMAN CLL. FINALLY, WE WILL ALSO DISCUSS DIFFERENT STRATEGIES UNDERTAKEN TO INTERVENE WITH THE NF-KAPPAB PATHWAY AND ITS UPSTREAM MEDIATORS. 2016 19 3261 28 HEPATITIS C VIRUS-INDUCED UP-REGULATION OF PROTEIN PHOSPHATASE 2A INHIBITS HISTONE MODIFICATION AND DNA DAMAGE REPAIR. THE MOLECULAR MECHANISMS UNDERLYING HEPATOCARCINOGENESIS IN CHRONIC VIRAL HEPATITIS ARE POORLY UNDERSTOOD. A POTENTIAL TUMORIGENIC PATHWAY COULD INVOLVE PROTEIN PHOSPHATASE 2A (PP2A) AND PROTEIN ARGININE METHYLTRANSFERASE 1 (PRMT1), BECAUSE BOTH ENZYMES ARE DYSREGULATED IN CHRONIC HEPATITIS C, AND BOTH ENZYMES HAVE BEEN INVOLVED IN CHROMATIN REMODELING AND DNA DAMAGE REPAIR. WE USED CELL LINES THAT ALLOW THE INDUCIBLE EXPRESSION OF HEPATITIS C VIRUS PROTEINS (UHCV57.3) AND OF THE CATALYTIC SUBUNIT OF PP2A (UPP2A-C8) AS WELL AS HUH7.5 CELLS INFECTED WITH RECOMBINANT CELL CULTURE-DERIVED HEPATITIS C VIRUS (HCVCC) TO STUDY EPIGENETIC HISTONE MODIFICATIONS AND DNA DAMAGE REPAIR. THE INDUCTION OF VIRAL PROTEINS, THE OVEREXPRESSION OF PP2AC, OR THE INFECTION OF HUH7.5 CELLS WITH HCVCC RESULTED IN AN INHIBITION OF HISTONE H4 METHYLATION/ACETYLATION AND HISTONE H2AX PHOSPHORYLATION, IN A SIGNIFICANTLY CHANGED EXPRESSION OF GENES IMPORTANT FOR HEPATOCARCINOGENESIS, AND INHIBITED DNA DAMAGE REPAIR. OVEREXPRESSION OF PP2AC IN NIH-3T3 CELLS INCREASED ANCHORAGE-INDEPENDENT GROWTH. THESE CHANGES WERE PARTIALLY REVERSED BY THE TREATMENT OF CELLS WITH THE METHYL-GROUP DONOR S-ADENOSYL-L-METHIONINE (SAME). CONCLUSION: HEPATITIS C VIRUS-INDUCED OVEREXPRESSION OF PP2AC CONTRIBUTES TO HEPATOCARCINOGENESIS THROUGH DYSREGULATION OF EPIGENETIC HISTONE MODIFICATIONS. THE CORRECTION OF DEFECTIVE HISTONE MODIFICATIONS BY S-ADENOSYL-L-METHIONINE MAKES THIS DRUG A CANDIDATE FOR CHEMOPREVENTIVE THERAPIES IN PATIENTS WITH CHRONIC HEPATITIS C WHO ARE AT RISK FOR DEVELOPING HEPATOCELLULAR CARCINOMA. 2010 20 4772 26 NUCLEAR SIRTUINS AND INFLAMMATORY SIGNALING PATHWAYS. THE REGULATION OF CHRONIC INFLAMMATION HAS RECEIVED CONSIDERABLE RESEARCH ATTENTION IN RECENT YEARS BECAUSE OF ITS CONTRIBUTION TO THE PATHOGENESIS OF CHRONIC DISEASES SUCH AS ARTHRITIS, DIABETES, METABOLIC SYNDROME AND OBESITY. THUS, STRATEGIES THAT INHIBIT THE INFLAMMATORY STATE MAY BE BENEFICIAL IN IMPROVING THE PATHOPHYSIOLOGY OF SEVERAL INFLAMMATION-RELATED DISORDERS. SIRTUINS ARE A FAMILY OF HISTONE DEACETYLASES THAT CONTAIN SEVEN ENZYMATIC ACTIVITIES IN MAMMALS (SIRT1-SIRT7) AND FUNCTION TO SUPPRESS GENE TRANSCRIPTION BY EPIGENETIC MECHANISMS. NUCLEAR SIRTUINS (SIRT 1, 2, 6 AND 7) IN PARTICULAR MAY PLAY AN IMPORTANT ROLE IN THE REGULATION OF INFLAMMATORY RESPONSES. IN THE PRESENT REVIEW, WE ASSESSED THE ROLES OF NUCLEAR SIRTUINS IN INFLAMMATORY REACTIONS: SIRT1 HAS BEEN SHOWN TO SUPPRESS NF-KAPPAB ACTIVITY, THE MASTER REGULATOR OF CELLULAR INFLAMMATORY RESPONSE, DECREASE COX-2 AND INOS PRODUCTION, AND INCREASE ANTIOXIDANT GENE EXPRESSION THAT SUPPRESSED INFLAMMATION. SIRT2 ACTIVITY INCLUDED THE DEACETYLATION OF P65 SUBUNIT OF NF-KAPPABETA AND RIP-1, WHILE SIRT6 HAS BEEN SHOWN TO INTERACT WITH P65/RELA BOUND TO THE NF-KAPPABETA PROMOTER REGION AND REPRESS TRANSCRIPTIONAL ACTIVITY. FURTHERMORE, RECENT STUDIES HAVE SHOWN THAT THE ABSENCE OF SIRT7 PRODUCED AN INCREASE IN INFLAMMATION, ILLUSTRATING THAT SIRT7 ALSO FUNCTIONED TO DECREASE INFLAMMATION. GIVEN THEIR SIGNIFICANT ROLES IN THE REGULATION OF CHRONIC INFLAMMATION, NUCLEAR SIRTUINS REPRESENT POTENTIAL THERAPEUTIC TARGETS IN THE CONTROL OF CHRONIC INFLAMMATORY DISEASES. 2017