1 3767 112 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 2 2737 32 EXPOSING A DEADLY ALLIANCE: NOVEL INSIGHTS INTO THE BIOLOGICAL LINKS BETWEEN COPD AND LUNG CANCER. CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) AFFECTS MORE THAN 200 MILLION PEOPLE WORLDWIDE AND IS EXPECTED TO BECOME THE THIRD LEADING CAUSE OF DEATH IN 2020. COPD IS CHARACTERIZED BY PROGRESSIVE AIRFLOW LIMITATION, DUE TO A COMBINATION OF CHRONIC INFLAMMATION AND REMODELING OF THE SMALL AIRWAYS (BRONCHIOLITIS) AND LOSS OF ELASTIC RECOIL CAUSED BY DESTRUCTION OF THE ALVEOLAR WALLS (EMPHYSEMA). LUNG CANCER IS THE MOST IMPORTANT CAUSE OF CANCER-RELATED DEATH IN THE WORLD. (CIGARETTE) SMOKING IS THE PRINCIPAL CULPRIT CAUSING BOTH COPD AND LUNG CANCER; IN ADDITION, EXPOSURE TO ENVIRONMENTAL TOBACCO SMOKE, BIOMASS FUEL SMOKE, COAL SMOKE AND OUTDOOR AIR POLLUTION HAVE ALSO BEEN ASSOCIATED WITH AN INCREASED INCIDENCE OF BOTH DISEASES. IMPORTANTLY, SMOKERS WITH COPD--DEFINED AS EITHER NOT FULLY REVERSIBLE AIRFLOW LIMITATION OR EMPHYSEMA--HAVE A TWO- TO FOUR-FOLD INCREASED RISK TO DEVELOP LUNG CANCER. IN THIS REVIEW, WE HIGHLIGHT SEVERAL OF THE GENETIC, EPIGENETIC AND INFLAMMATORY MECHANISMS, WHICH LINK COPD AND CARCINOGENESIS IN THE LUNGS. ELUCIDATING THE BIOLOGICAL PATHWAYS AND NETWORKS, WHICH UNDERLIE THE INCREASED SUSCEPTIBILITY OF LUNG CANCER IN PATIENTS WITH COPD, HAS IMPORTANT IMPLICATIONS FOR SCREENING, PREVENTION, DIAGNOSIS AND TREATMENT OF THESE TWO DEVASTATING PULMONARY DISEASES. 2013 3 4135 31 MECHANISMS OF LUNG DAMAGE AND DEVELOPMENT OF COPD DUE TO HOUSEHOLD BIOMASS-SMOKE EXPOSURE: INFLAMMATION, OXIDATIVE STRESS, MICRORNAS, AND GENE POLYMORPHISMS. CHRONIC EXPOSURE TO INDOOR BIOMASS SMOKE FROM THE COMBUSTION OF SOLID ORGANIC FUELS IS A MAJOR CAUSE OF DISEASE BURDEN WORLDWIDE. ALMOST 3 BILLION PEOPLE USE SOLID FUELS SUCH AS WOOD, CHARCOAL, AND CROP RESIDUES FOR INDOOR COOKING AND HEATING, ACCOUNTING FOR APPROXIMATELY 50% OF ALL HOUSEHOLDS AND 90% OF RURAL HOUSEHOLDS GLOBALLY. BIOMASS SMOKE CONTAINS MANY HAZARDOUS POLLUTANTS, RESULTING IN HOUSEHOLD AIR POLLUTION (HAP) EXPOSURE THAT OFTEN EXCEEDS INTERNATIONAL STANDARDS. LONG-TERM BIOMASS-SMOKE EXPOSURE IS ASSOCIATED WITH CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) IN ADULTS, A LEADING CAUSE OF MORBIDITY AND MORTALITY WORLDWIDE, CHRONIC BRONCHITIS, AND OTHER LUNG CONDITIONS. BIOMASS SMOKE-ASSOCIATED COPD DIFFERS FROM THE BEST-KNOWN CIGARETTE SMOKE-INDUCED COPD IN SEVERAL ASPECTS, SUCH AS A SLOWER DECLINE IN LUNG FUNCTION, GREATER AIRWAY INVOLVEMENT, AND LESS EMPHYSEMA, WHICH SUGGESTS A DIFFERENT PHENOTYPE AND PATHOPHYSIOLOGY. DESPITE THE HIGH BURDEN OF BIOMASS-ASSOCIATED COPD, THE MOLECULAR, GENETIC, AND EPIGENETIC MECHANISMS UNDERLYING ITS PATHOGENESIS ARE POORLY UNDERSTOOD. THIS REVIEW DESCRIBES THE PATHOGENIC MECHANISMS POTENTIALLY INVOLVED IN LUNG DAMAGE, THE DEVELOPMENT OF COPD ASSOCIATED WITH WOOD-DERIVED SMOKE EXPOSURE, AND THE INFLUENCE OF GENETIC AND EPIGENETIC FACTORS ON THE DEVELOPMENT OF THIS DISEASE. 2022 4 4954 17 PATHOGENESIS OF CHRONIC OBSTRUCTIVE PULMONARY DISEASE. THE PATHOGENESIS OF CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) ENCOMPASSES A NUMBER OF INJURIOUS PROCESSES, INCLUDING AN ABNORMAL INFLAMMATORY RESPONSE IN THE LUNGS TO INHALED PARTICLES AND GASES. OTHER PROCESSES, SUCH AS FAILURE TO RESOLVE INFLAMMATION, ABNORMAL CELL REPAIR, APOPTOSIS, ABNORMAL CELLULAR MAINTENANCE PROGRAMS, EXTRACELLULAR MATRIX DESTRUCTION (PROTEASE/ANTIPROTEASE IMBALANCE), AND OXIDATIVE STRESS (OXIDANT/ANTIOXIDANT IMBALANCE) ALSO HAVE A ROLE. THE INFLAMMATORY RESPONSES TO THE INHALATION OF ACTIVE AND PASSIVE TOBACCO SMOKE AND URBAN AND RURAL AIR POLLUTION ARE MODIFIED BY GENETIC AND EPIGENETIC FACTORS. THE SUBSEQUENT CHRONIC INFLAMMATORY RESPONSES LEAD TO MUCUS HYPERSECRETION, AIRWAY REMODELING, AND ALVEOLAR DESTRUCTION. THIS ARTICLE PROVIDES AN UPDATE ON THE CELLULAR AND MOLECULAR MECHANISMS OF THESE PROCESSES IN THE PATHOGENESIS OF COPD. 2007 5 5422 36 REGULATION OF LUNG EPITHELIAL CELL SENESCENCE IN SMOKING-INDUCED COPD/EMPHYSEMA BY MICROR-125A-5P VIA SP1 MEDIATION OF SIRT1/HIF-1A. CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) AFFECTS THE HEALTH OF MORE THAN 300 MILLION PEOPLE WORLDWIDE; AT PRESENT, THERE IS NO EFFECTIVE DRUG TO TREAT COPD. SMOKING IS THE MOST IMPORTANT RISK FACTOR, BUT THE MOLECULAR MECHANISM BY WHICH SMOKING CAUSES THE DISEASE IS UNCLEAR. THE SENESCENCE OF LUNG EPITHELIAL CELLS IS RELATED TO DEVELOPMENT OF COPD. REGULATION OF MIRNAS IS THE MAIN EPIGENETIC MECHANISM RELATED TO AGING. BETA-GALACTOSE STAINING SHOWED THAT THE LUNG TISSUES OF SMOKERS HAVE A HIGHER DEGREE OF CELLULAR SENESCENCE, AND THE EXPRESSION OF MIR-125A-5P IS HIGH. THIS EFFECT IS OBVIOUS FOR SMOKERS WITH COPD/EMPHYSEMA, AND THERE IS A NEGATIVE CORRELATION BETWEEN MIR-125A-5P LEVELS AND VALUES FOR FORCED EXPIRATORY VOLUME IN ONE SECOND (FEV1)/FORCED VITAL CAPACITY (FVC). AFTER BALB/C MICE WERE CHRONICALLY EXPOSED TO VARIOUS CONCENTRATIONS OF CIGARETTE SMOKE (CS), PLETHYSMOGRAPHY SHOWED THAT LUNG FUNCTION WAS IMPAIRED, LUNG TISSUE SENESCENCE WAS INCREASED, AND THE SENESCENCE-ASSOCIATED SECRETORY PHENOTYPE (SASP) IN BRONCHOALVEOLAR LAVAGE FLUID WAS INCREASED. FOR MOUSE LUNG EPITHELIAL (MLE)-12 CELLS TREATED WITH CIGARETTE SMOKE EXTRACT (CSE), SP1 AND SIRT1 LEVELS WERE LOW, HIF-1ALPHA ACETYLATION LEVELS WERE HIGH, AND CELL SENESCENCE AND SECRETION OF SASP FACTORS WERE ELEVATED. DOWN-REGULATION OF MIR-125A-5P OR UP-REGULATION OF SP1 REVERSED THESE EFFECTS. IN ADDITION, COMPARED WITH MICE EXPOSED TO CS, KNOCKDOWN OF MIR-125A-5P REDUCED LUNG EPITHELIAL CELL SENESCENCE AND COPD/EMPHYSEMA. THEREFORE, IN SMOKING-INDUCED COPD, ELEVATED MIR-125A-5P PARTICIPATES IN THE SENESCENCE OF LUNG EPITHELIAL CELLS THROUGH SP1/SIRT1/HIF-1ALPHA. THESE FINDINGS PROVIDE EVIDENCE RELATED TO THE PATHOGENESIS OF COPD/EMPHYSEMA CAUSED BY CHRONIC SMOKING. 2022 6 1245 32 CURRENT CONCEPTS ON THE ROLE OF INFLAMMATION IN COPD AND LUNG CANCER. CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) AND LUNG CANCER ARE LEADING CAUSE OF DEATH, AND BOTH ARE ASSOCIATED WITH CIGARETTE SMOKE EXPOSURE. IT HAS BEEN SHOWN THAT 50-70% OF PATIENTS DIAGNOSED WITH LUNG CANCER SUFFER FROM COPD, AND REDUCED LUNG FUNCTION IS AN IMPORTANT EVENT IN LUNG CANCER SUGGESTING AN ASSOCIATION BETWEEN COPD AND LUNG CANCER. HOWEVER, A CAUSAL RELATIONSHIP BETWEEN COPD AND LUNG TUMORIGENESIS IS NOT YET FULLY UNDERSTOOD. RECENT STUDIES HAVE SUGGESTED A CENTRAL ROLE OF CHRONIC INFLAMMATION IN THE PATHOGENESIS OF BOTH THE DISEASES. FOR EXAMPLE, IMMUNE DYSFUNCTION, ABNORMAL ACTIVATION OF NF-KAPPAB, EPITHELIAL-TO-MESENCHYMAL TRANSITION, ALTERED ADHESION SIGNALING PATHWAYS, AND EXTRACELLULAR MATRIX DEGRADATION/ALTERED SIGNALING ARE THE KEY UNDERLYING MECHANISMS IN BOTH COPD AND LUNG CANCER. THESE PARAMETERS ALONG WITH OTHER PROCESSES, SUCH AS CHROMATIN MODIFICATIONS/EPIGENETIC CHANGES, ANGIOGENESIS, AND AUTOPHAGY/APOPTOSIS ARE ALTERED BY CIGARETTE SMOKE, ARE CRUCIAL IN THE DEVELOPMENT OF COPD AND LUNG CANCER. UNDERSTANDING THE CELLULAR AND MOLECULAR MECHANISMS UNDERLYING THESE PROCESSES WILL PROVIDE NOVEL AVENUES FOR HALTING THE CHRONIC INFLAMMATION IN COPD AND DEVISING THERAPEUTIC STRATEGIES AGAINST LUNG CANCER. 2009 7 1244 30 CURRENT CONCEPTS ON OXIDATIVE/CARBONYL STRESS, INFLAMMATION AND EPIGENETICS IN PATHOGENESIS OF CHRONIC OBSTRUCTIVE PULMONARY DISEASE. CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) IS A GLOBAL HEALTH PROBLEM. THE CURRENT THERAPIES FOR COPD ARE POORLY EFFECTIVE AND THE MAINSTAYS OF PHARMACOTHERAPY ARE BRONCHODILATORS. A BETTER UNDERSTANDING OF THE PATHOBIOLOGY OF COPD IS CRITICAL FOR THE DEVELOPMENT OF NOVEL THERAPIES. IN THE PRESENT REVIEW, WE HAVE DISCUSSED THE ROLES OF OXIDATIVE/ALDEHYDE STRESS, INFLAMMATION/IMMUNITY, AND CHROMATIN REMODELING IN THE PATHOGENESIS OF COPD. AN IMBALANCE OF OXIDANTS/ANTIOXIDANTS CAUSED BY CIGARETTE SMOKE AND OTHER POLLUTANTS/BIOMASS FUELS PLAYS AN IMPORTANT ROLE IN THE PATHOGENESIS OF COPD BY REGULATING REDOX-SENSITIVE TRANSCRIPTION FACTORS (E.G., NF-KAPPAB), AUTOPHAGY AND UNFOLDED PROTEIN RESPONSE LEADING TO CHRONIC LUNG INFLAMMATORY RESPONSE. CIGARETTE SMOKE ALSO ACTIVATES CANONICAL/ALTERNATIVE NF-KAPPAB PATHWAYS AND THEIR UPSTREAM KINASES LEADING TO SUSTAINED INFLAMMATORY RESPONSE IN LUNGS. RECENTLY, EPIGENETIC REGULATION HAS BEEN SHOWN TO BE CRITICAL FOR THE DEVELOPMENT OF COPD BECAUSE THE EXPRESSION/ACTIVITY OF ENZYMES THAT REGULATE THESE EPIGENETIC MODIFICATIONS HAVE BEEN REPORTED TO BE ABNORMAL IN AIRWAYS OF COPD PATIENTS. HENCE, THE SIGNIFICANT ADVANCES MADE IN UNDERSTANDING THE PATHOPHYSIOLOGY OF COPD AS DESCRIBED HEREIN WILL IDENTIFY NOVEL THERAPEUTIC TARGETS FOR INTERVENTION IN COPD. 2011 8 6330 28 THE ROLE OF CIGARETTE SMOKE-INDUCED PULMONARY VASCULAR ENDOTHELIAL CELL APOPTOSIS IN COPD. CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) IS ONE OF THE MOST COMMON CHRONIC RESPIRATORY DISEASES WITH HIGH MORBIDITY AND MORTALITY. IT HAS BECOME THE FIFTH MOST BURDENED AND THE THIRD MOST DEADLY DISEASE IN THE GLOBAL ECONOMY AND INCREASES YEAR BY YEAR. THE PREVENTION AND TREATMENT OF COPD ARE URGENT. SMOKING IS THE MAIN AND MOST COMMON RISK FACTOR FOR COPD. CIGARETTE SMOKE (CS) CONTAINS A LARGE NUMBER OF TOXIC SUBSTANCES, CAN CAUSE A SERIES OF CHANGES IN THE TRACHEA, LUNG TISSUE, PULMONARY BLOOD VESSELS, AND PROMOTES THE OCCURRENCE AND DEVELOPMENT OF COPD. IN RECENT YEARS, THE DEVELOPMENT OF EPIGENETICS AND MOLECULAR BIOLOGY HAVE PROVIDED NEW GUIDANCE FOR REVEALING THE PATHOGENESIS, DIAGNOSIS, AND TREATMENT OF DISEASES. THE LATEST RESEARCH INDICATES THAT PULMONARY VASCULAR ENDOTHELIAL CELL APOPTOSIS INITIATES AND PARTICIPATES IN THE PATHOGENESIS OF COPD. IN THIS REVIEW, WE SUMMARIZE THE CURRENT RESEARCH ON THE EPIGENETIC MECHANISMS AND MOLECULAR BIOLOGY OF CS-INDUCED PULMONARY VASCULAR ENDOTHELIAL CELL APOPTOSIS IN COPD, PROVIDING A NEW RESEARCH DIRECTION FOR PATHOGENESIS OF COPD AND A NEW TARGET FOR THE DIAGNOSIS, TREATMENT, AND PREVENTION OF COPD. 2021 9 6440 22 THERAPEUTIC APPROACHES FOR CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) EXACERBATIONS. CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) IS A PROGRESSIVE PULMONARY DISORDER UNDERPINNED BY POORLY REVERSIBLE AIRFLOW RESULTING FROM CHRONIC BRONCHITIS OR EMPHYSEMA. THE PREVALENCE AND MORTALITY OF COPD CONTINUE TO INCREASE. PHARMACOTHERAPY FOR PATIENTS WITH COPD HAS INCLUDED ANTIBIOTICS, BRONCHODILATORS, AND ANTI-INFLAMMATORY CORTICOSTEROIDS (BUT WITH LITTLE SUCCESS). ORAL DISEASES HAVE LONG BEEN ESTABLISHED AS CLINICAL RISK FACTORS FOR DEVELOPING RESPIRATORY DISEASES. THE ESTABLISHMENT OF A VERY SIMILAR MICROBIOME IN THE MOUTH AND THE LUNG CONFIRMS THE ORAL-LUNG CONNECTION. THE ASPIRATION OF PATHOGENIC MICROBES FROM THE ORAL CAVITY HAS BEEN IMPLICATED IN SEVERAL RESPIRATORY DISEASES, INCLUDING PNEUMONIA AND CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD). THIS REVIEW FOCUSES ON CURRENT AND FUTURE PHARMACOTHERAPEUTIC APPROACHES FOR COPD EXACERBATION INCLUDING ANTIMICROBIALS, MUCOREGULATORS, THE USE OF BRONCHODILATORS AND ANTI-INFLAMMATORY DRUGS, MODIFYING EPIGENETIC MARKS, AND MODULATING DYSBIOSIS OF THE MICROBIOME. 2022 10 5299 38 PROTEIN INTERACTION NETWORKS PROVIDE INSIGHT INTO FETAL ORIGINS OF CHRONIC OBSTRUCTIVE PULMONARY DISEASE. BACKGROUND: CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) IS A LEADING CAUSE OF DEATH IN ADULTS THAT MAY HAVE ORIGINS IN EARLY LUNG DEVELOPMENT. IT IS A COMPLEX DISEASE, INFLUENCED BY MULTIPLE FACTORS INCLUDING GENETIC VARIANTS AND ENVIRONMENTAL FACTORS. MATERNAL SMOKING DURING PREGNANCY MAY INFLUENCE THE RISK FOR DISEASES DURING ADULTHOOD, POTENTIALLY THROUGH EPIGENETIC MODIFICATIONS INCLUDING METHYLATION. METHODS: IN THIS WORK, WE EXPLORE THE FETAL ORIGINS OF COPD BY UTILIZING LUNG DNA METHYLATION MARKS ASSOCIATED WITH IN UTERO SMOKE (IUS) EXPOSURE, AND EVALUATE THE NETWORK RELATIONSHIPS BETWEEN METHYLOMIC AND TRANSCRIPTOMIC SIGNATURES ASSOCIATED WITH ADULT LUNG TISSUE FROM FORMER SMOKERS WITH AND WITHOUT COPD. TO IDENTIFY POTENTIAL PATHOBIOLOGICAL MECHANISMS THAT MAY LINK FETAL LUNG, SMOKE EXPOSURE AND ADULT LUNG DISEASE, WE STUDY THE INTERACTIONS (PHYSICAL AND FUNCTIONAL) OF IDENTIFIED GENES USING PROTEIN-PROTEIN INTERACTION NETWORKS. RESULTS: WE BUILD IUS-EXPOSURE AND COPD MODULES, WHICH IDENTIFY CONNECTED SUBNETWORKS LINKING FETAL LUNG SMOKE EXPOSURE TO ADULT COPD. STUDYING THE RELATIONSHIPS AND CONNECTIVITY AMONG THE DIFFERENT MODULES FOR FETAL SMOKE EXPOSURE AND ADULT COPD, WE IDENTIFY ENRICHED PATHWAYS, INCLUDING THE AGE-RAGE AND FOCAL ADHESION PATHWAYS. CONCLUSIONS: THE MODULES IDENTIFIED IN OUR ANALYSIS ADD NEW AND POTENTIALLY IMPORTANT INSIGHTS TO UNDERSTANDING THE EARLY LIFE MOLECULAR PERTURBATIONS RELATED TO THE PATHOGENESIS OF COPD. WE IDENTIFY AGE-RAGE AND FOCAL ADHESION AS TWO BIOLOGICALLY PLAUSIBLE PATHWAYS THAT MAY REVEAL LUNG DEVELOPMENTAL CONTRIBUTIONS TO COPD. WE WERE NOT ONLY ABLE TO IDENTIFY MEANINGFUL MODULES BUT WERE ALSO ABLE TO STUDY INTERCONNECTIONS BETWEEN SMOKE EXPOSURE AND LUNG DISEASE, AUGMENTING OUR KNOWLEDGE ABOUT THE FETAL ORIGINS OF COPD. 2022 11 3447 29 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 12 5418 39 REGULATION OF DNA METHYLATION SIGNATURES ON NF-KAPPAB AND STAT3 PATHWAY GENES AND TET ACTIVITY IN CIGARETTE SMOKE EXTRACT-CHALLENGED CELLS/COPD EXACERBATION MODEL IN VITRO. BACKGROUND: CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) IS A GLOBAL HEALTH PROBLEM. CURRENTLY, THERE IS A LACK OF KNOWLEDGE ABOUT THE PATHOBIOLOGY OF THIS DISEASE AND AVAILABLE THERAPIES ARE INEFFECTIVE. CIGARETTE SMOKING IS THE LEADING CAUSE OF COPD; HOWEVER, NOT ALL SMOKERS DEVELOP COPD. EXACERBATIONS OF COPD CAUSED BY MICROBES ARE COMMON AND DETRIMENTAL. APPROXIMATELY 20-50% OF PATIENT EXACERBATIONS ARE CAUSED BY BACTERIAL COLONIZATION IN THE LOWER AIRWAYS. IT IS GENERALLY ACCEPTED THAT EPIGENETIC MECHANISMS, ESPECIALLY DNA METHYLATION, PLAY AN IMPORTANT ROLE DURING PROGRESSION OF COPD. THUS, WE HYPOTHESIZED THAT DNA METHYLATION PATTERNS VARY SIGNIFICANTLY FOLLOWING SMOKE EXPOSURE AND DURING EXACERBATIONS CAUSED BY BACTERIAL INFECTIONS. TO TEST OUR HYPOTHESIS, WE USED AN IN VITRO STUDY MODEL THAT MIMICS COPD EXACERBATIONS AND PERFORMED EXTENSIVE STUDIES TO UNDERSTAND THE ROLE OF CPG PROMOTER METHYLATION OF NF-KAPPAB AND STAT3-MEDIATED PATHWAY GENES. BOTH NF-KAPPAB AND STAT3 TRANSCRIPTION FACTORS PLAY CRITICAL ROLES IN ORCHESTRATING INFLAMMATORY RESPONSES DURING CIGARETTE SMOKE EXPOSURE. IN BRIEF, HUMAN LUNG ADENOCARCINOMA CELLS WITH TYPE II ALVEOLAR EPITHELIUM CHARACTERISTICS (A549) WERE CHALLENGED WITH CIGARETTE SMOKE EXTRACT (CSE) OR DMSO (CONTROL) FOLLOWED BY A 3-H CHALLENGE WITH BACTERIAL LIPOPOLYSACCHARIDE (LPS; FROM PSEUDOMONAS AERUGINOSA) PRIOR TO THE TERMINATION OF CSE EXPOSURE (COPD EXACERBATION GROUP). THE PRODUCTION OF CYTOKINES/CHEMOKINES, REGULATION OF TRANSCRIPTION FACTORS, AND DNA METHYLATION OF SPECIFIC GENES WERE THEN ASSESSED. WE ALSO STUDIED CHANGES IN THE EXPRESSION AND ACTIVITY OF TEN-ELEVEN TRANSLOCASES (TETS), THE ENZYMES RESPONSIBLE FOR DNA DEMETHYLATION, AND ASSESSED THEIR ROLE IN REGULATING DNA METHYLATION IN THE CSE-CHALLENGED GROUP. RESULTS: THERE WAS A SIGNIFICANT INCREASE IN THE RELEASE OF CYTOKINES/CHEMOKINES (IL-8, MCP-1, IL-6 AND CCL5) IN THE COPD EXACERBATION GROUP AS COMPARED TO THE CONTROL GROUP. HYPOMETHYLATION OF NF-KAPPAB-MEDIATED PATHWAY GENES CORRELATED WITH THEIR INDUCTION IN OUR COPD EXACERBATION STUDY MODEL. FURTHER, WE OBSERVED AN IMPORTANT ROLE OF TET1/2 IN REGULATING THE DNA METHYLATION OF NF-KAPPAB, STAT3, IKK, AND NIK GENES AND CYTOKINE/CHEMOKINE PRODUCTION BY A549 CELLS DURING CSE CHALLENGE. CONCLUSIONS: STUDIES TO FURTHER DEFINE THE ROLE OF TETS IN CSE-MEDIATED EPIGENETIC REGULATION MAY LEAD TO THE DEVELOPMENT OF BETTER AND MORE EFFECTIVE THERAPEUTIC INTERVENTION STRATEGIES FOR COPD. 2020 13 6915 21 [VULNERABILITY OF WOMEN TO TOBACCO: THE BRONCHO-PULMONARY CONSEQUENCES (ASTHMA, COPD)]. SMOKING REMAINS COMMON, WITH AN EXPOSURE THAT BEGINS EARLY DURING PREGNANCY. IT INDUCES EPIGENETIC CHANGES, WITH A TRANS-GENERATIONAL TRANSMISSION. SMOKING INCREASES THE RISK OF UNCONTROLLED ASTHMA DURING CHILDHOOD AND ADULT LIFE. ASTHMA IS ALSO ASSOCIATED WITH INCREASED RISK OF A DECLINE OF LUNG FUNCTION AND CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD). WOMEN ARE MORE AT RISK OF DEVELOPING EARLY AND SEVERE COPD. THE MECHANISMS ARE CURRENTLY POORLY KNOWN. 2019 14 927 32 CHRONIC INFLAMMATION, CHRONIC OBSTRUCTIVE PULMONARY DISEASE, AND LUNG CANCER. PURPOSE OF REVIEW: SMOKING IS A MAJOR RISK FACTOR FOR LUNG CANCER, WHICH IS THE LEADING CAUSE OF CANCER-RELATED DEATHS BOTH IN THE USA AND WORLDWIDE. CHRONIC OBSTRUCTIVE PULMONARY DISEASE AND EMPHYSEMA ARE COMORBID CONDITIONS OFTEN FOUND IN LUNG CANCER PATIENTS. THE INFLAMMATORY PATHWAYS THAT LINK CHRONIC OBSTRUCTIVE PULMONARY DISEASE, EMPHYSEMA, AND LUNG CANCER LIKELY INVOLVE GENETIC AND EPIGENETIC MODULATIONS DUE TO CHRONIC TISSUE INJURY AND ABNORMAL TUMOR IMMUNITY IN SUSCEPTIBLE HOSTS. RECENT FINDINGS: CHRONIC AIRWAY INFLAMMATION CONTRIBUTES TO ALTERATIONS IN THE BRONCHIAL EPITHELIUM AND LUNG MICROENVIRONMENT, PROVOKING A MILIEU CONDUCIVE TO PULMONARY CARCINOGENESIS. FOR EXAMPLE, INFLAMMATION-INDUCIBLE CYCLOOXYGENASE-2 IS UPREGULATED IN NONSMALL CELL LUNG CANCER AND ALSO PLAYS AN IMPORTANT ROLE IN PROMOTING EPITHELIAL-TO-MESENCHYMAL TRANSITION. GENETIC CHANGES IN THE AIRWAY EPITHELIUM OF SMOKERS MAY HELP PREDICT OR IDENTIFY INDIVIDUALS AT RISK FOR LUNG CANCER. FINALLY, RADIOGRAPHIC FINDINGS OF EMPHYSEMA HAVE BEEN ESTABLISHED AS INDEPENDENT RISK FACTORS FOR LUNG CANCER. SUMMARY: THE RELATIONSHIPS BETWEEN INFLAMMATION, AIRFLOW OBSTRUCTION, AND LUNG CANCER ARE COMPLEX. DEREGULATED INFLAMMATION IS COMPLICIT IN THE PATHOGENESIS OF CHRONIC OBSTRUCTIVE PULMONARY DISEASE AND LUNG CANCER, BUT THE OVERLAP OF SIGNALING EVENTS IS NOT YET FULLY UNDERSTOOD. TOBACCO EXPOSURE IS AN IMPORTANT RISK FACTOR THAT CONFERS LONG-TERM RISK OF LUNG DISEASE. DIAGNOSTIC SENSITIVITY OF DETECTING LUNG CANCER MAY IMPROVE WITH THE UTILIZATION OF GENETIC PROFILING IN COMBINATION WITH PATHOLOGIC EVALUATION OF AIRWAY EPITHELIUM. ADDITIONAL RESEARCH IS REQUIRED TO UNDERSTAND THE ROLE OF EPITHELIAL-TO-MESENCHYMAL TRANSITION IN CHRONIC INFLAMMATORY LUNG DISEASES AND LUNG CARCINOGENESIS. 2009 15 1012 41 CIGARETTE SMOKE INDUCES DISTINCT HISTONE MODIFICATIONS IN LUNG CELLS: IMPLICATIONS FOR THE PATHOGENESIS OF COPD AND LUNG CANCER. CIGARETTE SMOKE (CS)-MEDIATED OXIDATIVE STRESS INDUCES SEVERAL SIGNALING CASCADES, INCLUDING KINASES, WHICH RESULTS IN CHROMATIN MODIFICATIONS (HISTONE ACETYLATION/DEACETYLATION AND HISTONE METHYLATION/DEMETHYLATION). WE HAVE PREVIOUSLY REPORTED THAT CS INDUCES CHROMATIN REMODELING IN PRO-INFLAMMATORY GENE PROMOTERS; HOWEVER, THE UNDERLYING SITE-SPECIFIC HISTONE MARKS FORMED IN HISTONES H3 AND H4 DURING CS EXPOSURE IN LUNGS IN VIVO AND IN LUNG CELLS IN VITRO, WHICH CAN EITHER DRIVE GENE EXPRESSION OR REPRESSION, ARE NOT KNOWN. WE HYPOTHESIZE THAT CS EXPOSURE IN MOUSE AND HUMAN BRONCHIAL EPITHELIAL CELLS (H292) CAN CAUSE SITE-SPECIFIC POSTTRANSLATIONAL HISTONE MODIFICATIONS (PTMS) THAT MAY PLAY AN IMPORTANT ROLE IN THE PATHOGENESIS OF CS-INDUCED CHRONIC LUNG DISEASES. WE USED A BOTTOM-UP MASS SPECTROMETRY APPROACH TO IDENTIFY SOME POTENTIALLY NOVEL HISTONE MARKS, INCLUDING ACETYLATION, MONOMETHYLATION, AND DIMETHYLATION, IN SPECIFIC LYSINE AND ARGININE RESIDUES OF HISTONES H3 AND H4 IN MOUSE LUNGS AND H292 CELLS. WE FOUND THAT CS-INDUCED DISTINCT POSTTRANSLATIONAL HISTONE MODIFICATION PATTERNS IN HISTONE H3 AND HISTONE H4 IN LUNG CELLS, WHICH MAY BE CONSIDERED AS USABLE BIOMARKERS FOR CS-INDUCED CHRONIC LUNG DISEASES. THESE IDENTIFIED HISTONE MARKS (HISTONE H3 AND HISTONE H4) MAY PLAY AN IMPORTANT ROLE IN THE EPIGENETIC STATE DURING THE PATHOGENESIS OF SMOKING-INDUCED CHRONIC LUNG DISEASES, SUCH AS CHRONIC OBSTRUCTIVE PULMONARY DISEASE AND LUNG CANCER. 2014 16 3497 40 IDENTIFICATION OF NOVEL EPIGENETIC ABNORMALITIES AS SPUTUM BIOMARKERS FOR LUNG CANCER RISK AMONG SMOKERS AND COPD PATIENTS. OBJECTIVES: SMOKING IS A COMMON RISK FACTOR FOR CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) AND LUNG CANCER. ALTHOUGH COPD PATIENTS HAVE HIGHER RISK OF LUNG CANCER COMPARED TO NON-COPD SMOKERS, THE MOLECULAR LINKS BETWEEN THESE DISEASES ARE NOT WELL-DEFINED. THIS STUDY AIMS TO IDENTIFY GENES THAT ARE DOWNREGULATED BY CIGARETTE SMOKE AND COMMONLY REPRESSED IN COPD AND LUNG CANCER. MATERIALS AND METHODS: PRIMARY HUMAN AIRWAY EPITHELIAL CELLS (HAEC) WERE EXPOSED TO CIGARETTE-SMOKE-EXTRACT (CSE) FOR 10-WEEKS AND SIGNIFICANTLY SUPPRESSED GENES WERE IDENTIFIED BY TRANSCRIPTOME ARRAY. EPIGENETIC ABNORMALITIES OF THESE GENES IN LUNG ADENOCARCINOMA (LUAD) FROM PATIENTS WITH OR WITHOUT COPD WERE DETERMINED USING GENOME-WIDE AND GENE-SPECIFIC ASSAYS AND BY IN VITRO TREATMENT OF CELL LINES WITH TRICHOSTATIN-A OR 5-AZA-2-DEOXYCYTIDINE. RESULTS: THE TEN MOST COMMONLY DOWNREGULATED GENES FOLLOWING CHRONIC CSE EXPOSURE OF HAEC AND SHOW PROMOTER HYPERMETHYLATION IN LUAD WERE SELECTED. AMONG THESE, EXPRESSION OF CCNA1, SNCA, AND ZNF549 WAS SIGNIFICANTLY REDUCED IN LUNG TISSUES FROM COPD COMPARED WITH NON-COPD CASES WHILE EXPRESSION OF CCNA1 AND SNCA WAS FURTHER DOWNREGULATED IN TUMORS WITH COPD. THE PROMOTER REGIONS OF ALL THREE GENES WERE HYPERMETHYLATED IN LUAD BUT NOT NORMAL OR COPD LUNGS. THE REDUCED EXPRESSION AND ABERRANT PROMOTER HYPERMETHYLATION OF THESE GENES IN LUAD WERE INDEPENDENTLY VALIDATED USING DATA FROM THE CANCER GENOME ATLAS PROJECT. IMPORTANTLY, SNCA AND ZNF549 METHYLATION DETECTED IN SPUTUM DNA FROM LUAD (52% AND 38%) CASES WERE MORE PREVALENT COMPARED TO CANCER-FREE SMOKERS (26% AND 15%), RESPECTIVELY (P < 0.02). CONCLUSIONS: OUR DATA SHOW THAT SUPPRESSION OF CCNA1, SNCA, AND ZNF549 IN LUNG CANCER AND COPD OCCURS WITH OR WITHOUT PROMOTER HYPERMETHYLATION, RESPECTIVELY. DETECTING METHYLATION OF THESE AND PREVIOUSLY IDENTIFIED GENES IN SPUTUM OF CANCER-FREE SMOKERS MAY SERVE AS NON-INVASIVE BIOMARKERS FOR EARLY DETECTION OF LUNG CANCER AMONG HIGH RISK SMOKERS INCLUDING COPD PATIENTS. 2020 17 3543 27 IMMUNOLOGY, GENETICS AND MICROBIOTA IN THE COPD PATHOPHYSIOLOGY: POTENTIAL SCOPE FOR PATIENT STRATIFICATION. CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) IS CHARACTERIZED BY SUSTAINED INFLAMMATION OF THE AIRWAYS, LEADING TO DESTRUCTION OF LUNG TISSUE AND DECLINING PULMONARY FUNCTION. ALTHOUGH SMOKING IS THE MOST OBVIOUS RISK FACTOR FOR COPD, ONLY ABOUT 20% OF SMOKERS DEVELOP COPD AND SMOKING CESSATION DOES NOT REVERSE PROGRESSION OF COPD, INDICATING THAT WHILE SMOKING IS AN IMPORTANT CAUSE OR INITIATING FACTOR, IT IS NOT THE ONLY DRIVER OF ONGOING CHRONIC INFLAMMATION AND DISEASE PROGRESSION IN COPD PATIENTS. WE HYPOTHESIZE THAT SMOKING-INDUCED CHANGES IN LUNG MICROBIOTA, EPITHELIAL INTEGRITY AND EPIGENETIC CONTROL OF GENE EXPRESSION RESULT IN AUTOANTIGEN INDUCTION AND PERTURBED IMMUNE REGULATION IN GENETICALLY VUNERABLE INDIVIDUALS. IN OUR VIEW, COPD PATIENTS MAY BE STRATIFIED ACCORDING TO THEIR IMMUNOLOGICAL AND INFLAMMATORY STATUS RELATED TO SPECIFIC CHANGES IN THE LUNG MICROBIOTA (INNATE AND ADAPTIVE IMMUNITY), PRESENCE OF AUTOANTIGENS (ADAPTIVE IMMUNITY: TH1-B-CELL AXIS) AND EPIGENETIC MODIFICATIONS (INFLAMMATION AND STRUCTURAL CHANGES). 2015 18 5227 28 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 19 1551 37 DNA METHYLATION IS GLOBALLY DISRUPTED AND ASSOCIATED WITH EXPRESSION CHANGES IN CHRONIC OBSTRUCTIVE PULMONARY DISEASE SMALL AIRWAYS. DNA METHYLATION IS AN EPIGENETIC MODIFICATION THAT IS HIGHLY DISRUPTED IN RESPONSE TO CIGARETTE SMOKE AND INVOLVED IN A WIDE SPECTRUM OF MALIGNANT AND NONMALIGNANT DISEASES, BUT SURPRISINGLY NOT PREVIOUSLY ASSESSED IN SMALL AIRWAYS OF PATIENTS WITH CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD). SMALL AIRWAYS ARE THE PRIMARY SITES OF AIRFLOW OBSTRUCTION IN COPD. WE SOUGHT TO DETERMINE WHETHER DNA METHYLATION PATTERNS ARE DISRUPTED IN SMALL AIRWAY EPITHELIA OF PATIENTS WITH COPD, AND EVALUATE WHETHER CHANGES IN GENE EXPRESSION ARE ASSOCIATED WITH THESE DISRUPTIONS. GENOME-WIDE METHYLATION AND GENE EXPRESSION ANALYSIS WERE PERFORMED ON SMALL AIRWAY EPITHELIAL DNA AND RNA OBTAINED FROM THE SAME PATIENT DURING BRONCHOSCOPY, USING ILLUMINA'S INFINIUM HM27 AND AFFYMETRIX'S GENECHIP HUMAN GENE 1.0 ST ARRAYS. TO CONTROL FOR KNOWN EFFECTS OF CIGARETTE SMOKING ON DNA METHYLATION, METHYLATION AND GENE EXPRESSION PROFILES WERE COMPARED BETWEEN FORMER SMOKERS WITH AND WITHOUT COPD MATCHED FOR AGE, PACK-YEARS, AND YEARS OF SMOKING CESSATION. OUR RESULTS INDICATE THAT ABERRANT DNA METHYLATION IS (1) A GENOME-WIDE PHENOMENON IN SMALL AIRWAYS OF PATIENTS WITH COPD, AND (2) ASSOCIATED WITH ALTERED EXPRESSION OF GENES AND PATHWAYS IMPORTANT TO COPD, SUCH AS THE NF-E2-RELATED FACTOR 2 OXIDATIVE RESPONSE PATHWAY. DNA METHYLATION IS LIKELY AN IMPORTANT MECHANISM CONTRIBUTING TO MODULATION OF GENES IMPORTANT TO COPD PATHOLOGY. BECAUSE THESE METHYLATION EVENTS MAY UNDERLIE DISEASE-SPECIFIC GENE EXPRESSION CHANGES, THEIR CHARACTERIZATION IS A CRITICAL FIRST STEP TOWARD THE DEVELOPMENT OF EPIGENETIC MARKERS AND AN OPPORTUNITY FOR DEVELOPING NOVEL EPIGENETIC THERAPEUTIC INTERVENTIONS FOR COPD. 2014 20 4899 24 OXIDATIVE STRESS MEDIATES THE APOPTOSIS AND EPIGENETIC MODIFICATION OF THE BCL-2 PROMOTER VIA DNMT1 IN A CIGARETTE SMOKE-INDUCED EMPHYSEMA MODEL. BACKGROUND: EMPHYSEMA IS A CRUCIAL PATHOLOGICAL CHARACTERISTIC OF CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD). OXIDATIVE STRESS, APOPTOSIS AND EPIGENETIC MECHANISMS CONTRIBUTE TO THE PATHOGENESIS OF EMPHYSEMA. HOWEVER, AN ATTEMPT TO ACCURATELY IDENTIFY WHETHER THESE MECHANISMS INTERACT WITH EACH OTHER AND HOW THEY ARE TRIGGERED HAS NEVER BEEN CONDUCTED. METHOD: THE TOTAL REACTIVE OXYGEN SPECIES (ROS) LEVEL, PULMONARY APOPTOSIS AND B-CELL LYMPHOMA/LEUKEMIA-2 (BCL-2) EXPRESSION, AN APOPTOSIS REGULATOR, WERE DETECTED IN SAMPLES FROM COPD PATIENTS. BISULFITE SEQUENCING PCR (BSP) WAS CONDUCTED TO OBSERVE THE ALTERATIONS IN THE METHYLATION OF THE BCL-2 PROMOTER IN SPECIMENS. THE DYSREGULATION OF DNA METHYLTRANSFERASE ENZYME 1 (DNMT1), A VITAL DNA METHYLTRANSFERASE ENZYME, IN THE LUNGS OF PATIENTS WAS CONFIRMED THROUGH WESTERN BLOTTING. TO FIND OUT INTERACTIONS BETWEEN OXIDATIVE STRESS AND DNA METHYLATION IN EMPHYSEMA, MOUSE MODELS WERE BUILT WITH ANTIOXIDANT TREATMENT AND DNMT1 SILENCING, AND WERE EXAMINED WITH THE PULMONARY APOPTOSIS, BCL-2 AND DNMT1 LEVELS, AND EPIGENETIC ALTERATIONS OF BCL-2. RESULTS: HIGHER ROS LEVELS AND PULMONARY APOPTOSIS WERE OBSERVED IN COPD PATIENTS THAN IN HEALTHY CONTROLS. DOWNREGULATED BCL-2 EXPRESSION WITH INCREASED PROMOTER METHYLATION AND DNMT1 PROTEIN EXPRESSION WAS FOUND IN COPD PATIENTS. ANTIOXIDANT TREATMENT REDUCED THE LEVEL OF ROS, DNMT1 PROTEIN AND EMPHYSEMATOUS PROGRESSION IN THE SMOKING MODELS. FOLLOWING DNMT1 BLOCKADE, SMOKING MODELS SHOWED IMPROVED LUNG FUNCTION, PULMONARY APOPTOSIS, EMPHYSEMATOUS PROGRESSION, AND INCREASED BCL-2 PROTEIN LEVEL WITH LESS PROMOTER METHYLATION THAN EMPHYSEMA MICE. CONCLUSION: CIGARETTE-INDUCED OXIDATIVE STRESS MEDIATES PULMONARY APOPTOSIS AND HYPERMETHYLATION OF THE BCL-2 PROMOTER IN EMPHYSEMA MODELS THROUGH DNMT1. 2020