1 6687 83 VALIDATION OF THE EPIGENETIC READER BROMODOMAIN-CONTAINING PROTEIN 4 (BRD4) AS A THERAPEUTIC TARGET FOR TREATMENT OF AIRWAY REMODELING. STRUCTURAL REMODELING IS CENTRAL TO THE INITIATION AND PROGRESSION OF MANY CHRONIC LUNG DISEASES, REPRESENTING AN IMPORTANT UNMET NEED. WE EXAMINE THE EVIDENCE SUPPORTING BROMODOMAIN-CONTAINING PROTEIN 4 (BRD4) AS A VALIDATED BIOLOGICAL TARGET FOR TREATMENT OF AIRWAY REMODELING. IN EPITHELIAL CELLS AND FIBROBLASTS, BRD4 SERVES AS A SCAFFOLD FOR CHROMATIN REMODELING COMPLEXES IN ACTIVE SUPER-ENHANCERS. IN RESPONSE TO INFLAMMATORY STIMULI, BRD4 IS REPOSITIONED TO INNATE AND MESENCHYMAL GENES ACTIVATING THEIR PRODUCTION. PROOF-OF-CONCEPT STUDIES SHOW PROMISING BENEFIT OF SELECTIVE BRD4 INHIBITORS IN DISRUPTING EPITHELIAL MESENCHYMAL TRANSITION AND MYOFIBROBLAST TRANSITION IN DIVERSE MODELS OF LUNG INJURY. RECENT IDENTIFICATION OF BIOMARKERS OF BRD4 PROVIDES A BASIS FOR FURTHER DRUG DEVELOPMENT FOR APPLICATION IN VIRAL-INDUCED AIRWAY INFLAMMATION, COPD AND INTERSTITIAL LUNG DISEASES. 2020 2 5938 35 TARGETING INDUCIBLE EPIGENETIC REPROGRAMMING PATHWAYS IN CHRONIC AIRWAY REMODELING. ALLERGIC ASTHMA IS A CHRONIC INFLAMMATORY AIRWAY DISEASE WHOSE CLINICAL COURSE IS PUNCTUATED BY ACUTE EXACERBATIONS FROM AEROALLERGEN EXPOSURE OR RESPIRATORY VIRUS INFECTIONS. AEROALLERGENS AND RESPIRATORY VIRUSES STIMULATE TOLL-LIKE RECEPTOR (TLR) SIGNALING, PRODUCING OXIDATIVE INJURY AND INFLAMMATION. REPETITIVE EXACERBATIONS PRODUCE COMPLEX MUCOSAL ADAPTATIONS, CELL-STATE CHANGES, AND STRUCTURAL REMODELING. THESE STRUCTURAL CHANGES PRODUCE SUBSTANTIAL MORBIDITY, DECREASE LUNG CAPACITY, AND IMPAIR QUALITY OF LIFE. WE WILL REVIEW RECENT SYSTEMS-LEVEL STUDIES THAT PROVIDE FUNDAMENTAL NEW INSIGHTS INTO HOW REPETITIVE ACTIVATION OF INNATE SIGNALING PATHWAYS PRODUCE EPIGENETIC 'TRAINING' TO INDUCE ADAPTIVE EPITHELIAL RESPONSES. OXIDATIVE STRESS PRODUCED DOWNSTREAM OF TLR SIGNALING INDUCES TRANSIENT OXIDATION OF GUANINE BASES IN THE REGULATORY REGIONS OF INFLAMMATORY GENES. THE EPIGENETIC MARK 8-OXOG IS BOUND BY A PLEIOTROPIC DNA REPAIR ENZYME, 8-OXOGUANINE DNA GLYCOSYLASE (OGG1), WHICH INDUCES CONFORMATIONAL CHANGES IN ADJACENT DNA TO RECRUIT THE NFKAPPAB.BROMODOMAIN-CONTAINING PROTEIN 4 (BRD4) COMPLEX. THE NFKAPPAB.BRD4 COMPLEX NOT ONLY PLAYS A CENTRAL ROLE IN INFLAMMATION, BUT ALSO TRIGGERS MESENCHYMAL TRANSITION AND EXTRACELLULAR MATRIX REMODELING. SMALL MOLECULE INHIBITORS OF OGG1-8-OXOG BINDING AND BRD4-ACETYLATED HISTONE INTERACTION HAVE BEEN DEVELOPED. WE PRESENT STUDIES DEMONSTRATING EFFICACY OF THESE IN REDUCING AIRWAY INFLAMMATION IN PRECLINICAL MODELS. TARGETING INDUCIBLE EPIGENETIC REPROGRAMMING PATHWAY SHOWS PROMISE FOR THERAPEUTICS IN REVERSING AIRWAY REMODELING IN A VARIETY OF CHRONIC AIRWAY DISEASES. 2019 3 1251 19 CURRENT PERSPECTIVES ON ROLE OF CHROMATIN MODIFICATIONS AND DEACETYLASES IN LUNG INFLAMMATION IN COPD. CHROMATIN MODIFICATIONS AND EPIGENETIC REGULATION ARE CRITICAL FOR SUSTAINED AND ABNORMAL INFLAMMATORY RESPONSE SEEN IN LUNGS OF PATIENTS WITH CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) BECAUSE THE ACTIVITIES OF ENZYMES THAT REGULATE THESE EPIGENETIC MODIFICATIONS ARE ALTERED IN RESPONSE TO CIGARETTE SMOKE. CIGARETTE SMOKE INDUCES CHROMATIN MODIFICATIONS AND EPIGENETIC CHANGES BY CAUSING POST-TRANSLATIONAL MODIFICATIONS OF HISTONE ACETYLTRANSFERASES, AND HISTONE/NON-HISTONE DEACETYLASES (HDACS), SUCH AS HDAC2 AND SIRTUIN 1 (SIRT1), WHICH LEADS TO CHROMATIN REMODELING. IN THIS REVIEW, WE DISCUSSED THE CURRENT KNOWLEDGE ON CIGARETTE SMOKE/OXIDANTS-INDUCED POST-TRANSLATIONAL MODIFICATIONS OF DEACETYLASES (HDAC2 AND SIRT1), DISRUPTION OF HDAC2/SIRT1-RELA/P65 COREPRESSOR COMPLEX ASSOCIATED WITH ACETYLATION OF RELA/P65, AND CHROMATIN MODIFICATIONS (HISTONE H3 PHOSPHO-ACETYLATION) LEADING TO SUSTAINED PRO-INFLAMMATORY GENE TRANSCRIPTION. KNOWLEDGE ON MOLECULAR MECHANISMS OF EPIGENETIC CHANGES IN ABNORMAL LUNG INFLAMMATION WILL HELP IN UNDERSTANDING THE PATHOPHYSIOLOGY OF COPD WHICH MAY LEAD TO THE DEVELOPMENT OF NOVEL EPIGENETIC THERAPIES IN THE NEAR FUTURE. 2009 4 3757 18 INTEGRATED MECHANISMS OF CAMKII-DEPENDENT VENTRICULAR REMODELING. CAMKII HAS BEEN SHOWN TO BE ACTIVATED DURING DIFFERENT CARDIAC PATHOLOGICAL PROCESSES, AND CAMKII-DEPENDENT MECHANISMS CONTRIBUTE TO PATHOLOGICAL CARDIAC REMODELING, CARDIAC ARRHYTHMIAS, AND CONTRACTILE DYSFUNCTION DURING HEART FAILURE. ACTIVATION OF CAMKII DURING CARDIAC STRESS RESULTS IN A BROAD NUMBER OF BIOLOGICAL EFFECTS SUCH AS, ON THE ONE HAND, ACUTE EFFECTS DUE TO PHOSPHORYLATION OF DISTINCT CELLULAR PROTEINS AS ION CHANNELS AND CALCIUM HANDLING PROTEINS AND, ON THE OTHER HAND, INTEGRATIVE MECHANISMS BY CHANGING GENE EXPRESSION. THIS REVIEW FOCUSES ON TRANSCRIPTIONAL AND EPIGENETIC EFFECTS OF CAMKII ACTIVATION DURING CHRONIC CARDIAC REMODELING. MULTIPLE MECHANISMS HAVE BEEN DESCRIBED HOW CAMKII MEDIATES CHANGES IN CARDIAC GENE EXPRESSION. CAMKII HAS BEEN SHOWN TO DIRECTLY PHOSPHORYLATE COMPONENTS OF THE CARDIAC GENE REGULATION MACHINERY. CAMKII PHOSPHORYLATES SEVERAL TRANSCRIPTION FACTORS SUCH AS CREB THAT INDUCES THE ACTIVATION OF SPECIFIC GENE PROGRAMS. CAMKII ACTIVATES TRANSCRIPTIONAL REGULATORS ALSO INDIRECTLY BY PHOSPHORYLATING HISTONE DEACETYLASES, ESPECIALLY HDAC4, WHICH IN TURN INHIBITS TRANSCRIPTION FACTORS THAT DRIVE CARDIAC HYPERTROPHY, FIBROSIS, AND DYSFUNCTION. RECENT STUDIES DEMONSTRATE THAT CAMKII ALSO PHOSPHORYLATE DIRECTLY HISTONES, WHICH MAY CONTRIBUTE TO CHANGES IN GENE EXPRESSION. THESE FINDINGS OF CAMKII-DEPENDENT GENE REGULATION DURING CARDIAC REMODELING PROCESSES SUGGEST NOVEL STRATEGIES FOR CAMKII-DEPENDENT "TRANSCRIPTIONAL OR EPIGENETIC THERAPIES" TO CONTROL CARDIAC GENE EXPRESSION AND FUNCTION. MANIPULATION OF CAMKII-DEPENDENT SIGNALING PATHWAYS IN THE SETTINGS OF PATHOLOGICAL CARDIAC GROWTH, REMODELING, AND HEART FAILURE REPRESENTS AN AUSPICIOUS THERAPEUTIC APPROACH. 2014 5 6450 37 THERAPEUTIC TARGETS FOR INFLAMMATION-MEDIATED AIRWAY REMODELING IN CHRONIC LUNG DISEASE. ACUTE EXACERBATIONS OF CHRONIC LUNG DISEASE ACCOUNT FOR SUBSTANTIAL MORBIDITY AND HEALTH COSTS. REPEATED INFLAMMATORY EPISODES AND ATTENDANT BRONCHOCONSTRICTION CAUSE STRUCTURAL REMODELING OF THE AIRWAY. REMODELING IS A MULTICELLULAR RESPONSE TO MUCOSAL INJURY THAT RESULTS IN EPITHELIAL CELL-STATE CHANGES, ENHANCED EXTRACELLULAR DEPOSITION, AND EXPANSION OF PRO-FIBROTIC MYOFIBROBLAST POPULATIONS. AREAS COVERED: THIS MANUSCRIPT OVERVIEWS MECHANISTIC STUDIES IDENTIFYING KEY SENTINEL CELL POPULATIONS IN THE AIRWAY AND HOW PATTERN RECOGNITION SIGNALING INDUCES MALADAPTIVE MUCOSAL CHANGES AND AIRWAY REMODELING. STUDIES ELUCIDATING HOW NFKAPPAB COUPLES WITH AN ATYPICAL HISTONE ACETYLTRANSFERASE, BROMODOMAIN-CONTAINING PROTEIN 4 (BRD4) THAT REPROGRAMS MUCOSAL FIBROGENIC RESPONSES, ARE DESCRIBED. THE APPROACHES TO DEVELOPMENT AND CHARACTERIZATION OF SELECTIVE INHIBITORS OF EPIGENETIC REPROGRAMMING ON INNATE INFLAMMATION AND STRUCTURAL REMODELING IN PRECLINICAL MODELS ARE DETAILED. EXPERT COMMENTARY: BRONCHIOLAR CELLS DERIVED FROM SCGB1A1-EXPRESSING PROGENITORS FUNCTION AS MAJOR SENTINEL CELLS OF THE AIRWAY, RESPONSIBLE FOR INITIATING ANTIVIRAL AND AEROALLERGEN RESPONSES. IN THESE SENTINEL CELLS, ACTIVATION OF INNATE INFLAMMATION IS COUPLED TO NEUTROPHILIC RECRUITMENT, MESENCHYMAL TRANSITION AND MYOFIBROBLAST EXPANSION. THERAPEUTICS TARGETING THE NFKB-BRD4 MAY BE EFFICACIOUS IN REDUCING PATHOLOGICAL EFFECTS OF ACUTE EXACERBATIONS IN CHRONIC LUNG DISEASE. 2018 6 4661 19 NEW ASPECTS OF THE EPIGENETIC REGULATION OF EMT RELATED TO PULMONARY FIBROSIS. PULMONARY FIBROSIS IS A CHRONIC AND PROGRESSIVE FIBROTIC DISEASE THAT RESULTS IN IMPAIRED GAS EXCHANGE, VENTILATION, AND EVENTUAL DEATH. THE PRO-FIBROTIC ENVIRONMENT IS INSTIGATED BY VARIOUS FACTORS, LEADING TO THE TRANSFORMATION OF EPITHELIAL CELLS INTO MYOFIBROBLASTS AND/OR FIBROBLASTS THAT TRIGGER FIBROSIS. EPITHELIAL MESENCHYMAL TRANSITION (EMT) IS A BIOLOGICAL PROCESS THAT PLAYS A CRITICAL ROLE IN THE PATHOGENESIS OF PULMONARY FIBROSIS. EPIGENETIC REGULATION OF TISSUE-STROMAL CROSSTALK INVOLVING DNA METHYLATION, HISTONE MODIFICATIONS, NON-CODING RNA, AND CHROMATIN REMODELING PLAYS A KEY ROLE IN THE CONTROL OF EMT. THE REVIEW INVESTIGATES THE EPIGENETIC REGULATION OF EMT AND ITS SIGNIFICANCE IN PULMONARY FIBROSIS. 2023 7 866 23 CHRONIC ACTIVATION OF MUC1-C IN WOUND REPAIR PROMOTES PROGRESSION TO CANCER STEM CELLS. THE MUCIN 1 (MUC1) GENE EMERGED IN MAMMALS TO AFFORD PROTECTION OF BARRIER EPITHELIAL TISSUES FROM THE EXTERNAL ENVIRONMENT. MUC1 ENCODES A TRANSMEMBRANE C-TERMINAL (MUC1-C) SUBUNIT THAT IS ACTIVATED BY LOSS OF HOMEOSTASIS AND INDUCES INFLAMMATORY, PROLIFERATIVE, AND REMODELING PATHWAYS ASSOCIATED WITH WOUND REPAIR. AS A CONSEQUENCE, CHRONIC ACTIVATION OF MUC1-C PROMOTES LINEAGE PLASTICITY, EPIGENETIC REPROGRAMMING, AND CARCINOGENESIS. IN DRIVING CANCER PROGRESSION, MUC1-C IS IMPORTED INTO THE NUCLEUS, WHERE IT INDUCES NF-KAPPAB INFLAMMATORY SIGNALING AND THE EPITHELIAL-MESENCHYMAL TRANSITION (EMT). MUC1-C REPRESSES GENE EXPRESSION BY ACTIVATING (I) DNA METHYLTRANSFERASE 1 (DNMT1) AND DNMT3B, (II) POLYCOMB REPRESSIVE COMPLEX 1 (PRC1) AND PRC2, AND (III) THE NUCLEOSOME REMODELING AND DEACETYLASE (NURD) COMPLEX. PRC1/2-MEDIATED GENE REPRESSION IS COUNTERACTED BY THE SWI/SNF CHROMATIN REMODELING COMPLEXES. MUC1-C ACTIVATES THE SWI/SNF BAF AND PBAF COMPLEXES IN CANCER STEM CELL (CSC) MODELS WITH THE INDUCTION OF GENOME-WIDE DIFFERENTIALLY ACCESSIBLE REGIONS AND EXPRESSED GENES. MUC1-C REGULATES CHROMATIN ACCESSIBILITY OF ENHANCER-LIKE SIGNATURES IN ASSOCIATION WITH THE INDUCTION OF THE YAMANAKA PLURIPOTENCY FACTORS AND RECRUITMENT OF JUN AND BAF, WHICH PROMOTE INCREASES IN HISTONE ACTIVATION MARKS AND OPENING OF CHROMATIN. THESE AND OTHER FINDINGS DESCRIBED IN THIS REVIEW HAVE UNCOVERED A PIVOTAL ROLE FOR MUC1-C IN INTEGRATING LINEAGE PLASTICITY AND EPIGENETIC REPROGRAMMING, WHICH ARE TRANSIENT IN WOUND REPAIR AND SUSTAINED IN PROMOTING CSC PROGRESSION. 2022 8 2218 23 EPIGENETIC MODIFICATIONS IN FIBROTIC DISEASES: IMPLICATIONS FOR PATHOGENESIS AND PHARMACOLOGICAL TARGETS. ORGAN FIBROSIS IS A COMPLEX AND CHRONIC DISORDER THAT RESULTS FROM A VARIETY OF ACUTE INJURIES AND CONTRIBUTES TO THIRTY PERCENT OF NATURALLY OCCURRING DEATHS WORLDWIDE. THE MAIN FEATURE OF ORGAN FIBROSIS IS THE EXCESSIVE ACCUMULATION AND DEPOSIT OF EXTRACELLULAR MATRIX, THEREBY LEADING TO ORGAN DYSFUNCTION, LOSS OF ELASTICITY, AND DEVELOPMENT OF A RIGID ORGAN. ACCUMULATING EVIDENCE SHOWS THAT EPIGENETIC REMODELING, INCLUDING ABERRANT DNA METHYLATION AND NONCODING RNA EXPRESSION AS WELL AS HISTONE POST-TRANSLATIONAL MODIFICATIONS, PLAY IMPORTANT ROLES IN THE PATHOGENESIS OF FIBROSIS THROUGH THE REGULATION OF FIBROBLAST ACTIVATION, DIFFERENTIATION, AND APOPTOSIS, AS WELL AS COLLAGEN SYNTHESIS AND PROFIBROTIC GENE TRANSCRIPTION. IN THIS REVIEW, WE DISCUSS THE BASIC REGULATION OF DNA METHYLATION, NONCODING RNA EXPRESSION, AND HISTONE POST-TRANSLATIONAL MODIFICATION, AND THEIR PARTICIPATION IN THE PATHOGENESIS AND DEVELOPMENT OF ORGAN FIBROSIS. THIS REVIEW ALSO PROVIDES THE LATEST INSIGHTS INTO THE NOVEL BIOMARKERS AND THERAPEUTIC TARGETS FOR FIBROSIS THROUGH MODULATION OF EPIGENETIC REMODELING. 2015 9 2378 18 EPIGENETIC REGULATION OF VASCULAR SMOOTH MUSCLE CELL PHENOTYPE SWITCHING IN ATHEROSCLEROTIC ARTERY REMODELING: A MINI-REVIEW. ATHEROSCLEROSIS IS A CHRONIC INFLAMMATORY DISEASE CHARACTERIZED BY EXTENSIVE REMODELING OF MEDIUM AND LARGE-SIZED ARTERIES. INWARD REMODELING (=LUMEN SHRINKAGE) OF THE VASCULAR WALLS IS THE UNDERLYING CAUSE FOR ISCHEMIA IN TARGET ORGANS. THEREFORE, INWARD REMODELING CAN BE CONSIDERED THE PREDOMINANT FEATURE OF ATHEROSCLEROTIC PATHOLOGY. OUTWARD REMODELING (=LUMEN ENLARGEMENT) IS A PHYSIOLOGICAL RESPONSE COMPENSATING FOR LUMEN SHRINKAGE CAUSED BY NEOINTIMAL HYPERPLASIA, BUT AS A PATHOLOGICAL RESPONSE TO CHANGES IN BLOOD FLOW, OUTWARD REMODELING LEADS TO SUBSTANTIAL ARTERIAL WALL THINNING. THINNED VASCULAR WALLS ARE PRONE TO RUPTURE, AND SUBSEQUENT THROMBUS FORMATION ACCOUNTS FOR THE MAJORITY OF ACUTE CARDIOVASCULAR EVENTS. PATHOLOGICAL REMODELING IS DRIVEN BY INFLAMMATORY CELLS WHICH INDUCE VASCULAR SMOOTH MUSCLE CELLS TO SWITCH FROM QUIESCENT TO A PROLIFERATIVE AND MIGRATORY PHENOTYPE. AFTER DECADES OF INTENSIVE RESEARCH, THE MOLECULAR MECHANISMS OF ARTERIAL REMODELING ARE STARTING TO UNFOLD. IN THIS MINI-REVIEW, WE SUMMARIZE THE CURRENT KNOWLEDGE OF THE EPIGENETIC AND TRANSCRIPTIONAL REGULATION OF VASCULAR SMOOTH MUSCLE CELL PHENOTYPE SWITCHING FROM THE CONTRACTILE TO THE SYNTHETIC PHENOTYPE INVOLVED IN ARTERIAL REMODELING AND DISCUSS POTENTIAL THERAPEUTIC OPTIONS. 2021 10 6543 20 TRANSCRIPTOME REMODELING IN HYPOXIC INFLAMMATION. HYPOXIA IS AN INTEGRAL COMPONENT OF THE INFLAMED TISSUE MICROENVIRONMENT. TODAY, THE INFLUENCE OF HYPOXIA ON THE NATURAL EVOLUTION OF INFLAMMATORY RESPONSES IS WIDELY ACCEPTED; HOWEVER, MANY MOLECULAR AND CELLULAR MECHANISMS MEDIATING THIS RELATIONSHIP REMAIN TO BE CLARIFIED. HYPOXIC STRESS AFFECTS SEVERAL INDEPENDENT TRANSCRIPTIONAL REGULATORS RELATED TO INFLAMMATION IN WHICH HIF-1 AND NF-KAPPAB PLAY CENTRAL ROLES. TRANSCRIPTION FACTORS INTERACT WITH BOTH HATS AND HDACS, WHICH ARE COMPONENTS OF LARGE MULTIPROTEIN CO-REGULATORY COMPLEXES. THIS REVIEW SUMMARIZES THE CURRENT KNOWLEDGE ON HYPOXIA-RESPONSIVE TRANSCRIPTIONAL PATHWAYS IN INFLAMMATION AND THEIR IMPORTANCE IN THE ETIOLOGY OF CHRONIC INFLAMMATORY DISEASES, WITH THE PRIMARY FOCUS ON TRANSCRIPTIONAL CO-REGULATORS AND HISTONE MODIFICATIONS IN DEFINING GENE-SPECIFIC TRANSCRIPTIONAL RESPONSES IN HYPOXIA, AND ON THE RECENT PROGRESS IN THE UNDERSTANDING OF HYPOXIA-MEDIATED EPIGENETIC REPROGRAMMING. FURTHERMORE, THIS REVIEW DISCUSSES THE MOLECULAR CROSS-TALK BETWEEN GLUCOCORTICOID ANTI-INFLAMMATORY PATHWAYS AND HYPOXIA. 2010 11 4889 24 OXIDATIVE STRESS AND CHROMATIN REMODELING IN CHRONIC OBSTRUCTIVE PULMONARY DISEASE AND SMOKING-RELATED DISEASES. SIGNIFICANCE: CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) IS PREDOMINANTLY A TOBACCO SMOKE-TRIGGERED DISEASE WITH FEATURES OF CHRONIC LOW-GRADE SYSTEMIC INFLAMMATION AND AGING (INFLAMMAGING) OF THE LUNG ASSOCIATED WITH STEROID RESISTANCE INDUCED BY CIGARETTE SMOKE (CS)-MEDIATED OXIDATIVE STRESS. OXIDATIVE STRESS INDUCES VARIOUS KINASE SIGNALING PATHWAYS LEADING TO CHROMATIN MODIFICATIONS (HISTONE ACETYLATION/DEACETYLATION AND HISTONE METHYLATION/DEMETHYLATION) IN INFLAMMATION, SENESCENCE, AND STEROID RESISTANCE. RECENT ADVANCES: HISTONE MONO-, DI-, OR TRI-METHYLATION AT LYSINE RESIDUES RESULT IN EITHER GENE ACTIVATION (H3K4, H3K36, AND H3K79) OR REPRESSION (H3K9, H3K27, AND H3K20). CROSS-TALK OCCURS BETWEEN VARIOUS EPIGENETIC MARKS ON HISTONES AND DNA METHYLATION. BOTH CS AND OXIDANTS ALTER HISTONE ACETYLATION/DEACETYLATION AND METHYLATION/DEMETHYLATION LEADING TO ENHANCED PROINFLAMMATORY GENE EXPRESSION. CHROMATIN MODIFICATIONS OCCUR IN LUNGS OF PATIENTS WITH COPD. HISTONE DEACETYLASE 2 (HDAC2) REDUCTION (LEVELS AND ACTIVITY) IS ASSOCIATED WITH STEROID RESISTANCE IN RESPONSE TO OXIDATIVE STRESS. CRITICAL ISSUES: HISTONE MODIFICATIONS ARE ASSOCIATED WITH DNA DAMAGE/REPAIR AND EPIGENOMIC INSTABILITY AS WELL AS PREMATURE LUNG AGING, WHICH HAVE IMPLICATIONS IN THE PATHOGENESIS OF COPD. HDAC2/SIRTUIN1 (SIRT1)-DEPENDENT CHROMATIN MODIFICATIONS ARE ASSOCIATED WITH DNA DAMAGE-INDUCED INFLAMMATION AND SENESCENCE IN RESPONSE TO CS-MEDIATED OXIDATIVE STRESS. FUTURE DIRECTIONS: UNDERSTANDING CS/OXIDATIVE STRESS-MEDIATED CHROMATIN MODIFICATIONS AND THE CROSS-TALK BETWEEN HISTONE ACETYLATION AND METHYLATION WILL DEMONSTRATE THE INVOLVEMENT OF EPIGENETIC REGULATION OF CHROMATIN REMODELING IN INFLAMMAGING. THIS WILL LEAD TO IDENTIFICATION OF NOVEL EPIGENETIC-BASED THERAPIES AGAINST COPD AND OTHER SMOKING-RELATED LUNG DISEASES. PHARMACOLOGICAL ACTIVATION OF HDAC2/SIRT1 OR REVERSAL OF THEIR OXIDATIVE POST-TRANSLATIONAL MODIFICATIONS MAY OFFER THERAPIES FOR TREATMENT OF COPD AND CS-RELATED DISEASES BASED ON EPIGENETIC HISTONE MODIFICATIONS. 2013 12 2314 19 EPIGENETIC REGULATION OF ENDOTHELIAL-TO-MESENCHYMAL TRANSITION IN CHRONIC HEART DISEASE. ENDOTHELIAL-TO-MESENCHYMAL TRANSITION (ENDMT) IS A PROCESS IN WHICH ENDOTHELIAL CELLS LOSE THEIR PROPERTIES AND TRANSFORM INTO FIBROBLAST-LIKE CELLS. THIS TRANSITION PROCESS CONTRIBUTES TO CARDIAC FIBROSIS, A COMMON FEATURE OF PATIENTS WITH CHRONIC HEART FAILURE. TO DATE, NO SPECIFIC THERAPIES TO HALT OR REVERSE CARDIAC FIBROSIS ARE AVAILABLE, SO KNOWLEDGE OF THE UNDERLYING MECHANISMS OF CARDIAC FIBROSIS IS URGENTLY NEEDED. IN ADDITION, ENDMT CONTRIBUTES TO OTHER CARDIOVASCULAR PATHOLOGIES SUCH AS ATHEROSCLEROSIS AND PULMONARY HYPERTENSION, BUT ALSO TO CANCER AND ORGAN FIBROSIS. REMARKABLY, THE MOLECULAR MECHANISMS DRIVING ENDMT ARE LARGELY UNKNOWN. EPIGENETICS PLAY AN IMPORTANT ROLE IN REGULATING GENE TRANSCRIPTION AND TRANSLATION AND HAVE BEEN IMPLICATED IN THE ENDMT PROCESS. THEREFORE, EPIGENETICS MIGHT BE THE MISSING LINK IN UNRAVELING THE UNDERLYING MECHANISMS OF ENDMT. HERE, WE REVIEW THE INVOLVEMENT OF EPIGENETIC REGULATORS DURING ENDMT IN THE CONTEXT OF CARDIAC FIBROSIS. THE ROLE OF DNA METHYLATION, HISTONE MODIFICATIONS (ACETYLATION AND METHYLATION), AND NONCODING RNAS (MICRORNAS, LONG NONCODING RNAS, AND CIRCULAR RNAS) IN THE FACILITATION AND INHIBITION OF ENDMT ARE DISCUSSED, AND POTENTIAL THERAPEUTIC EPIGENETIC TARGETS WILL BE HIGHLIGHTED. 2018 13 689 30 BRD4 AS A THERAPEUTIC TARGET IN PULMONARY DISEASES. BROMODOMAIN AND EXTRA-TERMINAL DOMAIN (BET) PROTEINS ARE EPIGENETIC MODULATORS THAT REGULATE GENE TRANSCRIPTION THROUGH INTERACTING WITH ACETYLATED LYSINE RESIDUES OF HISTONE PROTEINS. BET PROTEINS HAVE MULTIPLE ROLES IN REGULATING KEY CELLULAR FUNCTIONS SUCH AS CELL PROLIFERATION, DIFFERENTIATION, INFLAMMATION, OXIDATIVE AND REDOX BALANCE, AND IMMUNE RESPONSES. AS A RESULT, BET PROTEINS HAVE BEEN FOUND TO BE ACTIVELY INVOLVED IN A BROAD RANGE OF HUMAN LUNG DISEASES INCLUDING ACUTE LUNG INFLAMMATION, ASTHMA, PULMONARY ARTERIAL HYPERTENSION, PULMONARY FIBROSIS, AND CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD). DUE TO THE IDENTIFICATION OF SPECIFIC SMALL MOLECULAR INHIBITORS OF BET PROTEINS, TARGETING BET IN THESE LUNG DISEASES HAS BECOME AN AREA OF INCREASING INTEREST. EMERGING EVIDENCE HAS DEMONSTRATED THE BENEFICIAL EFFECTS OF BET INHIBITORS IN PRECLINICAL MODELS OF VARIOUS HUMAN LUNG DISEASES. THIS IS, IN GENERAL, LARGELY RELATED TO THE ABILITY OF BET PROTEINS TO BIND TO PROMOTERS OF GENES THAT ARE CRITICAL FOR INFLAMMATION, DIFFERENTIATION, AND BEYOND. BY MODULATING THESE CRITICAL GENES, BET PROTEINS ARE INTEGRATED INTO THE PATHOGENESIS OF DISEASE PROGRESSION. THE INTRINSIC HISTONE ACETYLTRANSFERASE ACTIVITY OF BROMODOMAIN-CONTAINING PROTEIN 4 (BRD4) IS OF PARTICULAR INTEREST, SEEMS TO ACT INDEPENDENTLY OF ITS BROMODOMAIN BINDING ACTIVITY, AND HAS IMPLICATION IN SOME CONTEXTS. IN THIS REVIEW, WE PROVIDE A BRIEF OVERVIEW OF THE RESEARCH ON BET PROTEINS WITH A FOCUS ON BRD4 IN SEVERAL MAJOR HUMAN LUNG DISEASES, THE UNDERLYING MOLECULAR MECHANISMS, AS WELL AS FINDINGS OF TARGETING BET PROTEINS USING PHARMACEUTICAL INHIBITORS IN DIFFERENT LUNG DISEASES PRECLINICALLY. 2023 14 5857 27 SUBSTRATE-SPECIFIC BINDING OF 8-OXOGUANINE DNA GLYCOSYLASE 1 (OGG1) REPROGRAMS MUCOSAL ADAPTATIONS TO CHRONIC AIRWAY INJURY. RECENT ADVANCES HAVE UNCOVERED THE NON-RANDOM DISTRIBUTION OF 7, 8-DIHYDRO-8-OXOGUANINE (8-OXOGUA) INDUCED BY REACTIVE OXYGEN SPECIES, WHICH IS BELIEVED TO HAVE EPIGENETIC EFFECTS. ITS COGNATE REPAIR PROTEIN, 8-OXOGUANINE DNA GLYCOSYLASE 1 (OGG1), READS OXIDATIVE SUBSTRATES AND PARTICIPATES IN TRANSCRIPTIONAL INITIATION. WHEN REDOX SIGNALING IS ACTIVATED IN SMALL AIRWAY EPITHELIAL CELLS, THE DNA REPAIR FUNCTION OF OGG1 IS REPURPOSED TO TRANSMIT ACUTE INFLAMMATORY SIGNALS ACCOMPANIED BY CELL STATE TRANSITIONS AND MODIFICATION OF THE EXTRACELLULAR MATRIX. EPITHELIAL-MESENCHYMAL AND EPITHELIAL-IMMUNE INTERACTIONS ACT COOPERATIVELY TO ESTABLISH A LOCAL NICHE THAT INSTRUCTS THE MUCOSAL IMMUNE LANDSCAPE. IF THE TRANSITIONAL CELL STATE GOVERNED BY OGG1 REMAINS RESPONSIVE TO INFLAMMATORY MEDIATORS INSTEAD OF DIFFERENTIATION, THE COLLATERAL DAMAGE PROVIDES POSITIVE FEEDBACK TO INFLAMMATION, ASCRIBING INFLAMMATORY REMODELING TO ONE OF THE DRIVERS IN CHRONIC PATHOLOGIES. IN THIS REVIEW, WE DISCUSS THE SUBSTRATE-SPECIFIC READ THROUGH OGG1 HAS EVOLVED IN REGULATING THE INNATE IMMUNE RESPONSE, CONTROLLING ADAPTATIONS OF THE AIRWAY TO ENVIRONMENTAL AND INFLAMMATORY INJURY, WITH A FOCUS ON THE READER FUNCTION OF OGG1 IN INITIATION AND PROGRESSION OF EPITHELIAL TO MESENCHYMAL TRANSITIONS IN CHRONIC PULMONARY DISEASE. 2023 15 598 20 BETA-ADRENERGIC SIGNALING PROMOTES TUMOR ANGIOGENESIS AND PROSTATE CANCER PROGRESSION THROUGH HDAC2-MEDIATED SUPPRESSION OF THROMBOSPONDIN-1. CHRONIC BEHAVIORAL STRESS AND BETA-ADRENERGIC SIGNALING HAVE BEEN SHOWN TO PROMOTE CANCER PROGRESSION, WHOSE UNDERLYING MECHANISMS ARE LARGELY UNCLEAR, ESPECIALLY THE INVOLVEMENT OF EPIGENETIC REGULATION. HISTONE DEACETYLASE-2 (HDAC2), AN EPIGENETIC REGULATOR, IS CRITICAL FOR STRESS-INDUCED CARDIAC HYPERTROPHY. IT IS UNKNOWN WHETHER IT IS NECESSARY FOR BETA-ADRENERGIC SIGNALING-PROMOTED CANCER PROGRESSION. USING XENOGRAFT MODELS, WE SHOWED THAT CHRONIC BEHAVIORAL STRESS AND BETA-ADRENERGIC SIGNALING PROMOTE ANGIOGENESIS AND PROSTATE CANCER PROGRESSION. HDAC2 WAS INDUCED BY BETA-ADRENERGIC SIGNALING IN VITRO AND IN MOUSE XENOGRAFTS. WE NEXT UNCOVERED THAT HDAC2 IS A DIRECT TARGET OF CAMP RESPONSE ELEMENT-BINDING PROTEIN (CREB) THAT IS ACTIVATED BY BETA-ADRENERGIC SIGNALING. NOTABLY, HDAC2 IS NECESSARY FOR BETA-ADRENERGIC SIGNALING TO INDUCE ANGIOGENESIS. WE FURTHER DEMONSTRATED THAT, UPON CREB ACTIVATION, HDAC2 REPRESSES THROMBOSPONDIN-1 (TSP1), A POTENT ANGIOGENESIS INHIBITOR, THROUGH EPIGENETIC REGULATION. TOGETHER, THESE DATA ESTABLISH A NOVEL PATHWAY THAT HDAC2 AND TSP1 ACT DOWNSTREAM OF CREB ACTIVATION IN BETA-ADRENERGIC SIGNALING TO PROMOTE CANCER PROGRESSION. 2017 16 5560 21 ROLE OF HISTONE DEACETYLASE 2 IN EPIGENETICS AND CELLULAR SENESCENCE: IMPLICATIONS IN LUNG INFLAMMAGING AND COPD. HISTONE DEACETYLASE 2 (HDAC2) IS A CLASS I HISTONE DEACETYLASE THAT REGULATES VARIOUS CELLULAR PROCESSES, SUCH AS CELL CYCLE, SENESCENCE, PROLIFERATION, DIFFERENTIATION, DEVELOPMENT, APOPTOSIS, AND GLUCOCORTICOID FUNCTION IN INHIBITING INFLAMMATORY RESPONSE. HDAC2 HAS BEEN SHOWN TO PROTECT AGAINST DNA DAMAGE RESPONSE AND CELLULAR SENESCENCE/PREMATURE AGING VIA AN EPIGENETIC MECHANISM IN RESPONSE TO OXIDATIVE STRESS. THESE PHENOMENA ARE OBSERVED IN PATIENTS WITH CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD). HDAC2 IS POSTTRANSLATIONALLY MODIFIED BY OXIDATIVE/CARBONYL STRESS IMPOSED BY CIGARETTE SMOKE AND OXIDANTS, LEADING TO ITS REDUCTION VIA AN UBIQUITINATION-PROTEASOME DEPENDENT DEGRADATION IN LUNGS OF PATIENTS WITH COPD. IN THIS PERSPECTIVE, WE HAVE DISCUSSED THE ROLE OF HDAC2 POSTTRANSLATIONAL MODIFICATIONS AND ITS ROLE IN REGULATION OF INFLAMMATION, HISTONE/DNA EPIGENETIC MODIFICATIONS, DNA DAMAGE RESPONSE, AND CELLULAR SENESCENCE, PARTICULARLY IN INFLAMMAGING, AND DURING THE DEVELOPMENT OF COPD. WE HAVE ALSO DISCUSSED THE POTENTIAL DIRECTIONS FOR FUTURE TRANSLATIONAL RESEARCH AVENUES IN MODULATING LUNG INFLAMMAGING AND CELLULAR SENESCENCE BASED ON EPIGENETIC CHROMATIN MODIFICATIONS IN DISEASES ASSOCIATED WITH INCREASED OXIDATIVE STRESS. 2012 17 1709 23 DYSFUNCTIONAL ERG SIGNALING DRIVES PULMONARY VASCULAR AGING AND PERSISTENT FIBROSIS. VASCULAR DYSFUNCTION IS A HALLMARK OF CHRONIC DISEASES IN ELDERLY. THE CONTRIBUTION OF THE VASCULATURE TO LUNG REPAIR AND FIBROSIS IS NOT FULLY UNDERSTOOD. HERE, WE PERFORMED AN EPIGENETIC AND TRANSCRIPTIONAL ANALYSIS OF LUNG ENDOTHELIAL CELLS (ECS) FROM YOUNG AND AGED MICE DURING THE RESOLUTION OR PROGRESSION OF BLEOMYCIN-INDUCED LUNG FIBROSIS. WE IDENTIFIED THE TRANSCRIPTION FACTOR ETS-RELATED GENE (ERG) AS PUTATIVE ORCHESTRATOR OF LUNG CAPILLARY HOMEOSTASIS AND REPAIR, AND WHOSE FUNCTION IS DYSREGULATED IN AGING. ERG DYSREGULATION IS ASSOCIATED WITH REDUCED CHROMATIN ACCESSIBILITY AND MALADAPTIVE TRANSCRIPTIONAL RESPONSES TO INJURY. LOSS OF ENDOTHELIAL ERG ENHANCES PARACRINE FIBROBLAST ACTIVATION IN VITRO, AND IMPAIRS LUNG FIBROSIS RESOLUTION IN YOUNG MICE IN VIVO. SCRNA-SEQ OF ERG DEFICIENT MOUSE LUNGS REVEALES TRANSCRIPTIONAL AND FIBROGENIC ABNORMALITIES RESEMBLING THOSE ASSOCIATED WITH AGING AND HUMAN LUNG FIBROSIS, INCLUDING REDUCED NUMBER OF GENERAL CAPILLARY (GCAP) ECS. OUR FINDINGS DEMONSTRATE THAT LUNG ENDOTHELIAL CHROMATIN REMODELING DETERIORATES WITH AGING LEADING TO ABNORMAL TRANSCRIPTION, VASCULAR DYSREPAIR, AND PERSISTENT FIBROSIS FOLLOWING INJURY. 2022 18 172 21 ABSENCE OF HDAC3 BY MATRIX STIFFNESS PROMOTES CHROMATIN REMODELING AND FIBROBLAST ACTIVATION IN IDIOPATHIC PULMONARY FIBROSIS. IDIOPATHIC PULMONARY FIBROSIS (IPF) IS A CHRONIC AND FATAL DISEASE CHARACTERIZED BY PROGRESSIVE AND IRREVERSIBLE LUNG SCARRING ASSOCIATED WITH PERSISTENT ACTIVATION OF FIBROBLASTS. EPIGENETICS COULD INTEGRATE DIVERSE MICROENVIRONMENTAL SIGNALS, SUCH AS STIFFNESS, TO DIRECT PERSISTENT FIBROBLAST ACTIVATION. HISTONE MODIFICATIONS BY DEACETYLASES (HDAC) MAY PLAY AN ESSENTIAL ROLE IN THE GENE EXPRESSION CHANGES INVOLVED IN THE PATHOLOGICAL REMODELING OF THE LUNG. PARTICULARLY, HDAC3 IS CRUCIAL FOR MAINTAINING CHROMATIN AND REGULATING GENE EXPRESSION, BUT LITTLE IS KNOWN ABOUT ITS ROLE IN IPF. IN THE STUDY, CONTROL AND IPF-DERIVED FIBROBLASTS WERE USED TO DETERMINE THE INFLUENCE OF HDAC3 ON CHROMATIN REMODELING AND GENE EXPRESSION ASSOCIATED WITH IPF SIGNATURE. ADDITIONALLY, THE CELLS WERE GROWN ON HYDROGELS TO MIMIC THE STIFFNESS OF A FIBROTIC LUNG. OUR RESULTS SHOWED A DECREASED HDAC3 IN THE NUCLEUS OF IPF FIBROBLASTS, WHICH CORRELATES WITH CHANGES IN NUCLEUS SIZE AND HETEROCHROMATIN LOSS. THE INHIBITION OF HDAC3 WITH A PHARMACOLOGICAL INHIBITOR CAUSES HYPERACETYLATION OF H3K9 AND PROVOKES AN INCREASED EXPRESSION OF COL1A1, ACTA2, AND P21. COMPARABLE RESULTS WERE FOUND IN HYDROGELS, WHERE MATRIX STIFFNESS PROMOTES THE LOSS OF NUCLEAR HDAC3 AND INCREASES THE PROFIBROTIC SIGNATURE. FINALLY, LATRUNCULIN B WAS USED TO CONFIRM THAT CHANGES BY STIFFNESS DEPEND ON THE MECHANOTRANSDUCTION SIGNALS. TOGETHER, THESE RESULTS SUGGEST THAT HDAC3 COULD BE A LINK BETWEEN EPIGENETIC MECHANISMS AND THE FIBROTIC MICROENVIRONMENT. 2023 19 5993 20 TGFBETA PROMOTES FIBROSIS BY MYST1-DEPENDENT EPIGENETIC REGULATION OF AUTOPHAGY. ACTIVATION OF FIBROBLASTS IS ESSENTIAL FOR PHYSIOLOGICAL TISSUE REPAIR. UNCONTROLLED ACTIVATION OF FIBROBLASTS, HOWEVER, MAY LEAD TO TISSUE FIBROSIS WITH ORGAN DYSFUNCTION. ALTHOUGH SEVERAL PATHWAYS CAPABLE OF PROMOTING FIBROBLAST ACTIVATION AND TISSUE REPAIR HAVE BEEN IDENTIFIED, THEIR INTERPLAY IN THE CONTEXT OF CHRONIC FIBROTIC DISEASES REMAINS INCOMPLETELY UNDERSTOOD. HERE, WE PROVIDE EVIDENCE THAT TRANSFORMING GROWTH FACTOR-BETA (TGFBETA) ACTIVATES AUTOPHAGY BY AN EPIGENETIC MECHANISM TO AMPLIFY ITS PROFIBROTIC EFFECTS. TGFBETA INDUCES AUTOPHAGY IN FIBROTIC DISEASES BY SMAD3-DEPENDENT DOWNREGULATION OF THE H4K16 HISTONE ACETYLTRANSFERASE MYST1, WHICH REGULATES THE EXPRESSION OF CORE COMPONENTS OF THE AUTOPHAGY MACHINERY SUCH AS ATG7 AND BECLIN1. ACTIVATION OF AUTOPHAGY IN FIBROBLASTS PROMOTES COLLAGEN RELEASE AND IS BOTH, SUFFICIENT AND REQUIRED, TO INDUCE TISSUE FIBROSIS. FORCED EXPRESSION OF MYST1 ABROGATES THE STIMULATORY EFFECTS OF TGFBETA ON AUTOPHAGY AND RE-ESTABLISHES THE EPIGENETIC CONTROL OF AUTOPHAGY IN FIBROTIC CONDITIONS. INTERFERENCE WITH THE ABERRANT ACTIVATION OF AUTOPHAGY INHIBITS TGFBETA-INDUCED FIBROBLAST ACTIVATION AND AMELIORATES EXPERIMENTAL DERMAL AND PULMONARY FIBROSIS. THESE FINDINGS LINK UNCONTROLLED TGFBETA SIGNALING TO ABERRANT AUTOPHAGY AND DEREGULATED EPIGENETICS IN FIBROTIC DISEASES AND MAY CONTRIBUTE TO THE DEVELOPMENT OF THERAPEUTIC INTERVENTIONS IN FIBROTIC DISEASES. 2021 20 4097 22 MATRIX STIFFNESS REGULATES MACROPHAGE POLARIZATION IN ATHEROSCLEROSIS. ATHEROSCLEROSIS IS A CHRONIC INFLAMMATORY DISEASE AND THE PATHOLOGICAL BASIS OF MANY FATAL CARDIOVASCULAR DISEASES. MACROPHAGES, THE MAIN INFLAMMATORY CELLS IN ATHEROSCLEROTIC PLAQUE, HAVE A PARADOX ROLE IN DISEASE PROGRESSION. IN RESPONSE TO DIFFERENT MICROENVIRONMENTS, MACROPHAGES MAINLY HAVE TWO POLARIZED DIRECTIONS: PRO-INFLAMMATORY MACROPHAGES AND ANTI-INFLAMMATORY MACROPHAGES. MORE AND MORE EVIDENCE SHOWS THAT MACROPHAGE IS MECHANOSENSITIVE AND MATRIX STIFFNESS REGULATE MACROPHAGE PHENOTYPES IN ATHEROSCLEROSIS. HOWEVER, THE MOLECULAR MECHANISM OF MATRIX STIFFNESS REGULATING MACROPHAGE POLARIZATION STILL LACKS IN-DEPTH RESEARCH, WHICH HINDERS THE DEVELOPMENT OF NEW ANTI-ATHEROSCLEROTIC THERAPIES. IN THIS REVIEW, WE DISCUSS THE IMPORTANT ROLE OF MATRIX STIFFNESS IN REGULATING MACROPHAGE POLARIZATION THROUGH MECHANICAL SIGNAL TRANSDUCTION (HIPPO, PIEZO, CYTOSKELETON, AND INTEGRIN) AND EPIGENETIC MECHANISMS (MIRNA, DNA METHYLATION, AND HISTONE). WE HOPE TO PROVIDE A NEW PERSPECTIVE FOR ATHEROSCLEROSIS THERAPY BY TARGETING MATRIX STIFFNESS AND MACROPHAGE POLARIZATION. 2022