1 3449 155 HYPERMETHYLATION OF THE NRF2 PROMOTER INDUCES FERROPTOSIS BY INHIBITING THE NRF2-GPX4 AXIS IN COPD. BACKGROUND: NUCLEAR FACTOR E2-RELATED FACTOR 2 (NRF2) IS INVOLVED IN OXIDATIVE STRESS AND LUNG INFLAMMATION AND REGULATES THE ETIOLOGY OF CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD). FERROPTOSIS IS CHARACTERIZED BY THE ACCUMULATION OF LIPID REACTIVE OXYGEN SPECIES (ROS) VIA FERROUS ION-DEPENDENT FENTON REACTIONS AND IS INVOLVED IN COPD. HOWEVER, THE ROLE OF NRF2 IN FERROPTOSIS AND ITS EPIGENETIC REGULATION IN THE PATHOGENESIS OF COPD REMAIN UNCLEAR. METHODS: FERROPTOSIS WAS DETECTED BY 4-HNE, MDA, C11BODIPY, DCFH-DA, PEALS' STAINING AND CCK-8 ASSAYS. QPCR AND WESTERN BLOTTING WERE PERFORMED TO EXAMINE THE NRF2 LEVELS IN PERIPHERAL LUNG TISSUES, PRIMARY EPITHELIAL CELLS COLLECTED FROM PATIENTS WITH COPD AND SUBJECTS WITH NORMAL PULMONARY FUNCTION (NEVER-SMOKER [CONTROL-NS]; SMOKER [CONTROL-S]), AND CIGARETTE SMOKE EXTRACT (CSE)-TREATED HUMAN BRONCHIAL EPITHELIAL (HBE) CELLS. ELISA WAS USED TO QUANTIFY IL-8 AND IL-1BETA LEVELS. METHYLATION OF THE NRF2 PROMOTER WAS ANALYZED BY BISULFITE SEQUENCING AND PYROSEQUENCING. RESULTS: FERROPTOSIS WAS INVOLVED IN COPD AND GLUTATHIONE PEROXIDASE 4 (GPX4) EXPRESSION WAS DOWNREGULATED IN THE COPD GROUP. REACTIVE OXYGEN SPECIES (ROS), LIPID PEROXIDES AND MDA WERE INCREASED, BUT GPX4 AND SOD WERE EXHAUSTED IN CSE-TREATED HBE CELLS. THE PRODUCTION OF IL-1BETA AND IL-8 WAS PROMOTED IN HBE CELLS IN RESPONSE TO CSE BUT COULD BE REVERSED BY THE FERROPTOSIS INHIBITOR FER-1. THE NRF2 LEVEL WAS SIGNIFICANTLY DECREASED IN THE COPD GROUP COMPARED WITH THE CONTROL-S AND CONTROL-NS GROUPS. INCREASED NRF2 EXPRESSION ENHANCED GPX4 AND SOD LEVELS AND INHIBITED FERROPTOSIS AND PROINFLAMMATORY CYTOKINES IN THE SUPERNATANT. INHIBITION OF GPX4 REVERSED THE EFFECT OF NRF2 OVEREXPRESSION AND PROMOTED FERROPTOSIS. TWO SPECIFIC CPG SITES WITHIN THE NRF2 PROMOTER WERE HYPERMETHYLATED IN THE COPD GROUP. SIMILARLY, CSE-TREATED HBE CELLS EXHIBITED HYPERMETHYLATION OF THE NRF2 GENE. CONCLUSION: NRF2 EXPRESSION WAS DOWNREGULATED IN THE LUNGS OF COPD PATIENTS DUE TO HYPERMETHYLATION OF THE NRF2 PROMOTER, INHIBITING NRF2/GPX4 AND FERROPTOSIS, WHICH IS RELATED TO THE INITIATION AND PROGRESSION OF COPD. TARGETING NRF2/GPX4 MAY INHIBIT FERROPTOSIS, WHICH COULD PROVIDE STRATEGIES TO DELAY OR TREAT COPD. 2021 2 3767 36 INTEGRATIVE EPIGENOMIC ANALYSIS IN DIFFERENTIATED HUMAN PRIMARY BRONCHIAL EPITHELIAL CELLS EXPOSED TO CIGARETTE SMOKE. CIGARETTE SMOKE (CS) IS ONE OF THE MAJOR RISK FACTORS FOR MANY PULMONARY DISEASES, INCLUDING CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) AND LUNG CANCER. THE FIRST LINE OF DEFENSE FOR CS EXPOSURE IS THE BRONCHIAL EPITHELIAL CELLS. ELUCIDATION OF THE EPIGENETIC CHANGES DURING CS EXPOSURE IS KEY TO GAINING A MECHANISTIC UNDERSTANDING INTO HOW MATURE AND DIFFERENTIATED BRONCHIAL EPITHELIAL CELLS RESPOND TO CS. THEREFORE, WE PERFORMED EPIGENOMIC PROFILING IN CONJUNCTION WITH TRANSCRIPTIONAL PROFILING IN WELL-DIFFERENTIATED HUMAN BRONCHIAL EPITHELIAL (HBE) CELLS CULTURED IN AIR-LIQUID INTERFACE (ALI) EXPOSED TO THE VAPOR PHASE OF CS. THE GENOME-WIDE ENRICHMENT OF HISTONE 3 LYSINE 27 ACETYLATION WAS DETECTED BY CHROMATIN IMMUNOPRECIPITATION FOLLOWED BY NEXT GENERATION SEQUENCING (CHIP-SEQ) IN HBE CELLS AND SUGGESTED THE PLAUSIBLE BINDING OF SPECIFIC TRANSCRIPTION FACTORS RELATED TO CS EXPOSURE. ADDITIONALLY, INTERROGATION OF CHIP-SEQ DATA WITH GENE EXPRESSION PROFILING OF HBE CELLS AFTER CS EXPOSURE FOR DIFFERENT DURATIONS (3 HOURS, 2 DAYS, 4 DAYS) SUGGESTED THAT EARLIER EPIGENETIC CHANGES (3 HOURS AFTER CS EXPOSURE) MAY BE ASSOCIATED WITH LATER GENE EXPRESSION CHANGES INDUCED BY CS EXPOSURE (4 DAYS). THE INTEGRATION OF EPIGENETICS AND GENE EXPRESSION DATA REVEALED SIGNALING PATHWAYS RELATED TO CS-INDUCED EPIGENETIC CHANGES IN HBE CELLS THAT MAY IDENTIFY NOVEL REGULATORY PATHWAYS RELATED TO CS-INDUCED COPD. 2018 3 3447 55 HYPERMETHYLATION OF MITOCHONDRIAL TRANSCRIPTION FACTOR A INDUCED BY CIGARETTE SMOKE IS ASSOCIATED WITH CHRONIC OBSTRUCTIVE PULMONARY DISEASE. PURPOSE OF THE STUDY: CIGARETTE SMOKING IS A LEADING ENVIRONMENTAL CONTRIBUTOR TO CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD), BUT ITS EPIGENETIC REGULATION OF MTTFA GENE REMAINS ELUSIVE. THIS STUDY AIMS TO EXPLORE THE RELATIONSHIP OF DNA METHYLATION OF MTTFA AND CIGARETTE SMOKING IN COPD. MATERIALS AND METHODS: WE ANALYZED DNA METHYLATION ON MTTFA PROMOTERS IN CLINICAL SAMPLES FROM COPD PATIENTS AND SUBJECTS WITH NORMAL PULMONARY FUNCTION. EXPRESSION OF MTTFA MRNA IN THE CLINICAL SAMPLES AND MTTFA MRNA AND PROTEIN IN HUMAN UMBILICAL VEIN ENDOTHELIAL CELLS(HUVECS) TREATED WITH CIGARETTE SMOKE EXTRACT (CSE) WAS EVALUATED. MTTFA MRNA AND PROTEIN LEVELS WERE MEASURED TO DETERMINE EFFECTS OF DEMETHYLATION AGENTS ON CSE-TREATED HUVECS. RESULTS: THE DNA METHYLATION LEVEL OF THE MTTFA PROMOTER WAS SIGNIFICANTLY INCREASED IN COPD GROUP. EXPRESSION OF MTTFA MRNA WAS DOWNREGULATED IN THE LUNGS AS A CONSEQUENCE OF HYPERMETHYLATION OF MTTFA PROMOTER. EXPRESSION OF MTTFA MRNA AND PROTEIN WAS DOWNREGULATED IN CSE-TREATED HUVECS AS A CONSEQUENCE OF HYPERMETHYLATION OF THE MTTFA PROMOTER. MTTFA EXPRESSION IN CSE-TREATED HUVECS WAS RESTORED BY THE METHYLATION INHIBITOR, 5-AZA-2'-DEOXYCYTIDINE(AZA). CONCLUSIONS: CIGARETTE SMOKE-INDUCED HYPERMETHYLATION OF THE MTTFA PROMOTER IS RELATED TO THE INITIATION AND PROGRESSION OF COPD. OUR FINDING MAY PROVIDE A NEW STRATEGY FOR THE INTERVENTION OF COPD BY DEVELOPING DEMETHYLATION AGENTS TARGETING MTTFA HYPERMETHYLATION. 2019 4 137 39 ABERRANT DNA METHYLATION AND EXPRESSION OF SPDEF AND FOXA2 IN AIRWAY EPITHELIUM OF PATIENTS WITH COPD. BACKGROUND: GOBLET CELL METAPLASIA, A COMMON FEATURE OF CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD), IS ASSOCIATED WITH MUCUS HYPERSECRETION WHICH CONTRIBUTES TO THE MORBIDITY AND MORTALITY AMONG PATIENTS. TRANSCRIPTION FACTORS SAM-POINTED DOMAIN-CONTAINING ETS-LIKE FACTOR (SPDEF) AND FORKHEAD BOX PROTEIN A2 (FOXA2) REGULATE GOBLET CELL DIFFERENTIATION. THIS STUDY AIMED TO (1) INVESTIGATE DNA METHYLATION AND EXPRESSION OF SPDEF AND FOXA2 DURING GOBLET CELL DIFFERENTIATION AND (2) COMPARE THIS IN AIRWAY EPITHELIAL CELLS FROM PATIENTS WITH COPD AND CONTROLS DURING MUCOCILIARY DIFFERENTIATION. METHODS: TO ASSESS DNA METHYLATION AND EXPRESSION OF SPDEF AND FOXA2 DURING GOBLET CELL DIFFERENTIATION, PRIMARY AIRWAY EPITHELIAL CELLS, ISOLATED FROM TRACHEA (NON-COPD CONTROLS) AND BRONCHIAL TISSUE (PATIENTS WITH COPD), WERE DIFFERENTIATED BY CULTURE AT THE AIR-LIQUID INTERFACE (ALI) IN THE PRESENCE OF CYTOKINE INTERLEUKIN (IL)-13 TO PROMOTE GOBLET CELL DIFFERENTIATION. RESULTS: WE FOUND THAT SPDEF EXPRESSION WAS INDUCED DURING GOBLET CELL DIFFERENTIATION, WHILE FOXA2 EXPRESSION WAS DECREASED. IMPORTANTLY, CPG NUMBER 8 IN THE SPDEF PROMOTER WAS HYPERMETHYLATED UPON DIFFERENTIATION, WHEREAS DNA METHYLATION OF FOXA2 PROMOTER WAS NOT CHANGED. IN THE ABSENCE OF IL-13, COPD-DERIVED ALI-CULTURED CELLS DISPLAYED HIGHER SPDEF EXPRESSION THAN CONTROL-DERIVED ALI CULTURES, WHEREAS NO DIFFERENCE WAS FOUND FOR FOXA2 EXPRESSION. THIS WAS ACCOMPANIED WITH HYPOMETHYLATION OF CPG NUMBER 6 IN THE SPDEF PROMOTER AND ALSO HYPOMETHYLATION OF CPG NUMBERS 10 AND 11 IN THE FOXA2 PROMOTER. CONCLUSIONS: THESE FINDINGS SUGGEST THAT ABERRANT DNA METHYLATION OF SPDEF AND FOXA2 IS ONE OF THE FACTORS UNDERLYING MUCUS HYPERSECRETION IN COPD, OPENING NEW AVENUES FOR EPIGENETIC-BASED INHIBITION OF MUCUS HYPERSECRETION. 2017 5 5227 39 PRMT6 MEDIATES INFLAMMATION VIA ACTIVATION OF THE NF-KAPPAB/P65 PATHWAY ON A CIGARETTE SMOKE EXTRACT-INDUCED MURINE EMPHYSEMA MODEL. INTRODUCTION: SMOKE-DRIVEN LUNG INFLAMMATION IS CONSIDERED TO BE THE MAJOR PATHOPHYSIOLOGY MECHANISM OF CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD)/EMPHYSEMA. PROTEIN ARGININE METHYLTRANSFERASE 6 (PRMT6) IS A KEY EPIGENETIC ENZYME, WHICH IS RELATED TO PROTECTING THE TRI-METHYLATION OF H3K4 (H3K4ME3). WE HYPOTHESIZED THAT PTMT6 PROTECTS LUNG INFLAMMATION THROUGH THE NUCLEAR FACTOR KAPPA B (NF-KAPPAB) PATHWAY. METHODS: MICE WERE INJECTED WITH CIGARETTE SMOKE EXTRACT (CSE) OR PBS TO ESTABLISH A MICE MODEL, INTRATRACHEALLY INSTILLED WITH OVEREXPRESSED PRMT6 OR NEGATIVE CONTROL VECTOR. MORPHOMETRY OF LUNG SLIDES AND LUNG FUNCTION WERE MEASURED. WE DETERMINED THE PROTEIN EXPRESSION OF PRMT6 AND ITS RELATED HISTONE TARGETS, THE ACTIVATION OF NF-KAPPAB PATHWAY, THE LEVEL OF TUMOR NECROSIS FACTOR ALPHA (TNFALPHA) AND INTERLEUKIN-1BETA (IL-1BETA). RESULTS: AFTER PRMT6 OVEREXPRESSION, THE MORPHOMETRY INDEXES AND LUNG FUNCTION WERE IMPROVED. ALSO, THE EXPRESSION OF H3K4ME3 WAS DECREASED. OVEREXPRESSED PRMT6 COULD SUPPRESS CSE-INDUCED NF-KAPPAB ACTIVATION AND PRO-INFLAMMATION GENES EXPRESSION. CONCLUSIONS: THE OVEREXPRESSED PRMT6 COULD SERVE AS AN INFLAMMATION INHIBITOR, POTENTIALLY THROUGH BLOCKING THE NF-KAPPAB/P65 PATHWAY IN THE MURINE EMPHYSEMA MODEL. 2020 6 5479 48 RESVERATROL ATTENUATES CIGARETTE SMOKE EXTRACT INDUCED CELLULAR SENESCENCE IN HUMAN AIRWAY EPITHELIAL CELLS BY REGULATING THE MIR-34A/SIRT1/NF-KAPPAB PATHWAY. CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) IS CHARACTERIZED BY ACCELERATED LUNG AGING. SMOKING IS THE CRITICAL RISK FACTOR FOR COPD. CELLULAR SENESCENCE OF AIRWAY EPITHELIAL CELLS IS THE CYTOLOGICAL BASIS OF ACCELERATED LUNG AGING IN COPD, AND THE REGULATION OF MICRORNAS (MIRNAS) IS THE CENTRAL EPIGENETIC MECHANISM OF CELLULAR SENESCENCE. RESVERATROL (RES) IS A POLYPHENOL WITH ANTI-AGING PROPERTIES. THIS STUDY INVESTIGATED WHETHER RES ATTENUATES CIGARETTE SMOKE EXTRACT (CSE)-INDUCED CELLULAR SENESCENCE IN HUMAN AIRWAY EPITHELIAL CELLS (BEAS-2B) THROUGH THE MIR-34A/SIRT1/NUCLEAR FACTOR-KAPPAB (NF-KAPPAB) PATHWAY. BEAS-2B CELLS WERE TREATED WITH RES, CSE AND TRANSFECTED WITH MIR-34A-5P MIMICS. CELLULAR SENESCENCE WAS EVALUATED BY SENESCENCE -RELATED BETA-GALACTOSIDASE (SA-BETA-GAL) STAINING AND EXPRESSION OF SENESCENCE-RELATED GENES (P16, P21, AND P53). THE EXPRESSIONS OF MIR-34A-5P, SIRT1, AND NF-KAPPAB P65 WERE EXAMINED USING QUANTITATIVE REAL TIME POLYMERASE CHAIN REACTION AND WESTERN BLOTTING. THE SENESCENCE-ASSOCIATED SECRETORY PHENOTYPE (SASP) CYTOKINES (IL-1BETA, IL-6, IL-8, TNF-ALPHA) WERE ASSESSED BY ENZYME-LINKED IMMUNOSORBENT ASSAY. THE BINDING BETWEEN MIR-34A-5P AND SIRT1 WAS CONFIRMED BY DUAL-LUCIFERASE REPORTER ASSAY. THE RESULTS SHOWED THAT CSE DOSE-DEPENDENTLY DECREASED CELL VIABILITY AND ELEVATED CELLULAR SENESCENCE, CHARACTERIZED BY INCREASED SA-BETA-GAL STAINING AND SENESCENCE-RELATED GENE EXPRESSIONS (P16, P21, AND P53). FURTHER, CSE DOSE-DEPENDENTLY INCREASED THE EXPRESSION OF MIR-34A-5P AND SASP CYTOKINES (IL-1BETA, IL-6, IL-8, TNF-ALPHA) IN BEAS-2B CELLS. PRETREATMENT WITH RES INHIBITED CSE-INDUCED CELLULAR SENESCENCE AND SECRETION OF SASP CYTOKINES (IL-1BETA, IL-6, IL-8, TNF-ALPHA) IN A DOSE-DEPENDENT MANNER. MOREOVER, RES REVERSED THE CSE-INDUCED DOWN-REGULATION OF SIRT1 AND UP-REGULATION OF MIR-34A-5P AND NF-KAPPAB P65. SIRT1 IS A TARGET OF MIR-34A-5P. OVEREXPRESSION OF MIR-34A-5P VIA TRANSFECTION WITH MIR-34A-5P MIMIC IN BEAS-2B CELLS ATTENUATED THE INHIBITORY EFFECT OF RES ON CELLULAR SENESCENCE, ACCOMPANIED BY REVERSING THE EXPRESSION OF SIRT1 AND NF-KAPPAB P65. IN CONCLUSION, RES ATTENUATED CSE-INDUCED CELLULAR SENESCENCE IN BEAS-2B CELLS BY REGULATING THE MIR-34A/SIRT1/NF-KAPPAB PATHWAY, WHICH MAY PROVIDE A NEW APPROACH FOR COPD TREATMENT. 2022 7 3329 35 HISTONE DEACETYLASE 6-MEDIATED SELECTIVE AUTOPHAGY REGULATES COPD-ASSOCIATED CILIA DYSFUNCTION. CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) INVOLVES ABERRANT AIRWAY INFLAMMATORY RESPONSES TO CIGARETTE SMOKE (CS) THAT ARE ASSOCIATED WITH EPITHELIAL CELL DYSFUNCTION, CILIA SHORTENING, AND MUCOCILIARY CLEARANCE DISRUPTION. EXPOSURE TO CS REDUCED CILIA LENGTH AND INDUCED AUTOPHAGY IN VIVO AND IN DIFFERENTIATED MOUSE TRACHEAL EPITHELIAL CELLS (MTECS). AUTOPHAGY-IMPAIRED (BECN1+/- OR MAP1LC3B-/-) MICE AND MTECS RESISTED CS-INDUCED CILIA SHORTENING. FURTHERMORE, CS INCREASED THE AUTOPHAGIC TURNOVER OF CILIARY PROTEINS, INDICATING THAT AUTOPHAGY MAY REGULATE CILIA HOMEOSTASIS. WE IDENTIFIED CYTOSOLIC DEACETYLASE HDAC6 AS A CRITICAL REGULATOR OF AUTOPHAGY-MEDIATED CILIA SHORTENING DURING CS EXPOSURE. MICE BEARING AN X CHROMOSOME DELETION OF HDAC6 (HDAC6-/Y) AND MTECS FROM THESE MICE HAD REDUCED AUTOPHAGY AND WERE PROTECTED FROM CS-INDUCED CILIA SHORTENING. AUTOPHAGY-IMPAIRED BECN1-/-, MAP1LC3B-/-, AND HDAC6-/Y MICE OR MICE INJECTED WITH AN HDAC6 INHIBITOR WERE PROTECTED FROM CS-INDUCED MUCOCILIARY CLEARANCE (MCC) DISRUPTION. MCC WAS PRESERVED IN MICE GIVEN THE CHEMICAL CHAPERONE 4-PHENYLBUTYRIC ACID, BUT WAS DISRUPTED IN MICE LACKING THE TRANSCRIPTION FACTOR NRF2, SUGGESTING THAT OXIDATIVE STRESS AND ALTERED PROTEOSTASIS CONTRIBUTE TO THE DISRUPTION OF MCC. ANALYSIS OF HUMAN COPD SPECIMENS REVEALED EPIGENETIC DEREGULATION OF HDAC6 BY HYPOMETHYLATION AND INCREASED PROTEIN EXPRESSION IN THE AIRWAYS. WE CONCLUDE THAT AN AUTOPHAGY-DEPENDENT PATHWAY REGULATES CILIA LENGTH DURING CS EXPOSURE AND HAS POTENTIAL AS A THERAPEUTIC TARGET FOR COPD. 2013 8 6297 53 THE PROTECTIVE EFFECT OF HBO1 ON CIGARETTE SMOKE EXTRACT-INDUCED APOPTOSIS IN AIRWAY EPITHELIAL CELLS. PURPOSE: EPIGENETIC MODIFICATION IS ONE OF MOST IMPORTANT MECHANISMS UNDERLYING THE PATHOGENESIS OF CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD). THE PURPOSE OF THIS STUDY WAS TO DETERMINE WHETHER HISTONE ACETYLTRANSFERASE BINDING TO ORC1 (HBO1) CAN PROTECT AGAINST CIGARETTE SMOKE (CS)-INDUCED CELL APOPTOSIS AND SUSTAIN NORMAL HISTONE ACETYLATION IN COPD. METHODS: HUMAN LUNG TISSUE SAMPLES WERE OBTAINED FROM PATIENTS WHO UNDERWENT LUNG RESECTION. THE EMPHYSEMA MOUSE MODEL AND HBO1 OVEREXPRESSING MICE WERE EACH ESTABLISHED BY INTRAPERITONEAL INJECTION WITH CIGARETTE SMOKE EXTRACT (CSE) OR INTRATRACHEAL LENTIVIRAL VECTORS INSTILLATION. TUNEL (TERMINAL DEOXYNUCLEOTIDYL TRANSFERASE DUTP NICK END LABELING) ASSAYS WERE USED TO ASSESS APOPTOTIC RATIO IN MICE. THE APOPTOSIS OF HUMAN BRONCHIAL EPITHELIAL CELLS (HBECS) WAS ASSAYED BY FLOW CYTOMETRY. HBO1, B-CELL LYMPHOMA-2 (BCL-2), AND H3K14AC PROTEIN EXPRESSION WERE DETECTED BY WESTERN BLOTTING. HBO1 MRNA EXPRESSION WAS MEASURED BY QUANTITATIVE REAL-TIME POLYMERASE CHAIN REACTION. RESULTS: PROTEIN EXPRESSION OF HBO1 WAS DECREASED SIGNIFICANTLY IN LUNG TISSUE FROM COPD PATIENTS AND CSE-TREATED EMPHYSEMA MOUSE MODELS. OVEREXPRESSION OF HBO1 ATTENUATED CSE-INDUCED EMPHYSEMATOUS CHANGES, AS WELL AS APOPTOSIS IN THE LUNGS OF COPD MICE. IN VITRO, THE HBO1 PROTEIN DEGRADED IN A TIME- AND DOSE-DEPENDENT COURSE WITH CSE TREATMENT. WITH FLOW CYTOMETRY, WE PROVED THAT HBO1 COULD REVERSE THE APOPTOSIS OF HBECS INDUCED BY CSE. FURTHERMORE, HBO1 OVEREXPRESSION PROMOTED THE EXPRESSION OF ANTI-APOPTOTIC BCL-2 PROTEIN AND ENHANCED H3K14 ACETYLATION IN AIRWAY EPITHELIAL CELLS. CONCLUSION: THESE FINDINGS DEMONSTRATE THAT THE KEY HISTONE MODULATOR HBO1 PLAYS A PROTECTIVE ROLE IN COPD PATHOGENESIS THAT MAY SHED LIGHT ON POTENTIAL THERAPEUTIC TARGETS TO INHIBIT THE PROGRESS OF COPD. 2020 9 3939 46 LNC-IL7R ALLEVIATES PM(2.5)-MEDIATED CELLULAR SENESCENCE AND APOPTOSIS THROUGH EZH2 RECRUITMENT IN CHRONIC OBSTRUCTIVE PULMONARY DISEASE. BACKGROUND: LONG-TERM EXPOSURE TO PM(2.5) (PARTICULATE MATTER WITH AN AERODYNAMIC DIAMETER OF