1 5910 113 TARGETED EPIGENETIC EDITING OF SPDEF REDUCES MUCUS PRODUCTION IN LUNG EPITHELIAL CELLS. AIRWAY MUCUS HYPERSECRETION CONTRIBUTES TO THE MORBIDITY AND MORTALITY IN PATIENTS WITH CHRONIC INFLAMMATORY LUNG DISEASES. REDUCING MUCUS PRODUCTION IS CRUCIAL FOR IMPROVING PATIENTS' QUALITY OF LIFE. THE TRANSCRIPTION FACTOR SAM-POINTED DOMAIN-CONTAINING ETS-LIKE FACTOR (SPDEF) PLAYS A CRITICAL ROLE IN THE REGULATION OF MUCUS PRODUCTION AND, THEREFORE, REPRESENTS A POTENTIAL THERAPEUTIC TARGET. THIS STUDY AIMS TO REDUCE LUNG EPITHELIAL MUCUS PRODUCTION BY TARGETED SILENCING SPDEF USING THE NOVEL STRATEGY, EPIGENETIC EDITING. ZINC FINGERS AND CRISPR/DCAS PLATFORMS WERE ENGINEERED TO TARGET REPRESSORS (KRAB, DNA METHYLTRANSFERASES, HISTONE METHYLTRANSFERASES) TO THE SPDEF PROMOTER. ALL CONSTRUCTS WERE ABLE TO EFFECTIVELY SUPPRESS BOTH SPDEF MRNA AND PROTEIN EXPRESSION, WHICH WAS ACCOMPANIED BY INHIBITION OF DOWNSTREAM MUCUS-RELATED GENES [ANTERIOR GRADIENT 2 (AGR2), MUCIN 5AC (MUC5AC)]. FOR THE HISTONE METHYLTRANSFERASE G9A, AND NOT ITS MUTANT OR OTHER EFFECTORS, THE OBTAINED SILENCING WAS MITOTICALLY STABLE. THESE RESULTS INDICATE EFFICIENT SPDEF SILENCING AND DOWNREGULATION OF MUCUS-RELATED GENE EXPRESSION BY EPIGENETIC EDITING, IN HUMAN LUNG EPITHELIAL CELLS. THIS OPENS AVENUES FOR EPIGENETIC EDITING AS A NOVEL THERAPEUTIC STRATEGY TO INDUCE LONG-LASTING MUCUS INHIBITION. 2017 2 137 44 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 3 4116 26 MECHANISMS OF AIRWAY EPITHELIAL INJURY AND ABNORMAL REPAIR IN ASTHMA AND COPD. THE AIRWAY EPITHELIUM COMPRISES OF DIFFERENT CELL TYPES AND ACTS AS A PHYSICAL BARRIER PREVENTING PATHOGENS, INCLUDING INHALED PARTICLES AND MICROBES, FROM ENTERING THE LUNGS. GOBLET CELLS AND SUBMUCOSAL GLANDS PRODUCE MUCUS THAT TRAPS PATHOGENS, WHICH ARE EXPELLED FROM THE RESPIRATORY TRACT BY CILIATED CELLS. BASAL CELLS ACT AS PROGENITOR CELLS, DIFFERENTIATING INTO DIFFERENT EPITHELIAL CELL TYPES, TO MAINTAIN HOMEOSTASIS FOLLOWING INJURY. ADHERENS AND TIGHT JUNCTIONS BETWEEN CELLS MAINTAIN THE EPITHELIAL BARRIER FUNCTION AND REGULATE THE MOVEMENT OF MOLECULES ACROSS IT. IN THIS REVIEW WE DISCUSS HOW ABNORMAL EPITHELIAL STRUCTURE AND FUNCTION, CAUSED BY CHRONIC INJURY AND ABNORMAL REPAIR, DRIVES AIRWAY DISEASE AND SPECIFICALLY ASTHMA AND CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD). IN BOTH DISEASES, INHALED ALLERGENS, POLLUTANTS AND MICROBES DISRUPT JUNCTIONAL COMPLEXES AND PROMOTE CELL DEATH, IMPAIRING THE BARRIER FUNCTION AND LEADING TO INCREASED PENETRATION OF PATHOGENS AND A CONSTANT AIRWAY IMMUNE RESPONSE. IN ASTHMA, THE INFLAMMATORY RESPONSE PRECIPITATES THE EPITHELIAL INJURY AND DRIVES ABNORMAL BASAL CELL DIFFERENTIATION. THIS LEADS TO REDUCED CILIATED CELLS, GOBLET CELL HYPERPLASIA AND INCREASED EPITHELIAL MESENCHYMAL TRANSITION, WHICH CONTRIBUTE TO IMPAIRED MUCOCILIARY CLEARANCE AND AIRWAY REMODELLING. IN COPD, CHRONIC OXIDATIVE STRESS AND INFLAMMATION TRIGGER PREMATURE EPITHELIAL CELL SENESCENCE, WHICH CONTRIBUTES TO LOSS OF EPITHELIAL INTEGRITY AND AIRWAY INFLAMMATION AND REMODELLING. INCREASED NUMBERS OF BASAL CELLS SHOWING DEREGULATED DIFFERENTIATION, CONTRIBUTES TO CILIARY DYSFUNCTION AND MUCOUS HYPERPRODUCTION IN COPD AIRWAYS. DEFECTIVE ANTIOXIDANT, ANTIVIRAL AND DAMAGE REPAIR MECHANISMS, POSSIBLY DUE TO GENETIC OR EPIGENETIC FACTORS, MAY CONFER SUSCEPTIBILITY TO AIRWAY EPITHELIAL DYSFUNCTION IN THESE DISEASES. THE CURRENT EVIDENCE SUGGESTS THAT A CONSTANT CYCLE OF INJURY AND ABNORMAL REPAIR OF THE EPITHELIUM DRIVES CHRONIC AIRWAY INFLAMMATION AND REMODELLING IN ASTHMA AND COPD. MECHANISTIC UNDERSTANDING OF INJURY SUSCEPTIBILITY AND DAMAGE RESPONSE MAY LEAD TO IMPROVED THERAPIES FOR THESE DISEASES. 2023 4 4954 18 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 2581 29 EPIGENETICS OF MUCUS HYPERSECRETION IN CHRONIC RESPIRATORY DISEASES. ASTHMA, CHRONIC OBSTRUCTIVE PULMONARY DISEASE, AND CYSTIC FIBROSIS ARE THREE CHRONIC PULMONARY DISEASES THAT AFFECT AN ESTIMATED 420 MILLION INDIVIDUALS ACROSS THE GLOBE. A KEY FACTOR CONTRIBUTING TO EACH OF THESE CONDITIONS IS MUCUS HYPERSECRETION. ALTHOUGH MANAGEMENT OF THESE DISEASES IS VASTLY STUDIED, RESEARCHERS HAVE ONLY BEGUN TO SCRATCH THE SURFACE OF THE MECHANISMS CONTRIBUTING TO MUCUS HYPERSECRETION. EPIGENETIC REGULATION OF MUCUS HYPERSECRETION, OTHER THAN MICRORNA POST-TRANSLATIONAL MODIFICATION, IS EVEN MORE SCARCELY RESEARCHED. DETAILED STUDY OF EPIGENETIC MECHANISMS, SUCH AS DNA METHYLATION AND HISTONE MODIFICATION, COULD NOT ONLY HELP TO BETTER THE UNDERSTANDING OF THESE RESPIRATORY CONDITIONS BUT ALSO REVEAL NEW TREATMENTS FOR THEM. BECAUSE MUCUS HYPERSECRETION IS SUCH A COMPLEX EVENT, THERE ARE INNUMERABLE GENES INVOLVED IN THE PROCESS, WHICH ARE BEYOND THE SCOPE OF A SINGLE REVIEW. THEREFORE, THE PURPOSE OF THIS REVIEW IS TO NARROW THE FOCUS AND SUMMARIZE SPECIFIC EPIGENETIC RESEARCH THAT HAS BEEN CONDUCTED ON A FEW ASPECTS OF MUCUS HYPERSECRETION IN ASTHMA, CHRONIC OBSTRUCTIVE PULMONARY DISEASE, CYSTIC FIBROSIS, AND SOME CANCERS. SPECIFICALLY, THIS REVIEW EMPHASIZES THE CONTRIBUTION OF DNA METHYLATION AND HISTONE MODIFICATION OF PARTICULAR GENES INVOLVED IN MUCUS HYPERSECRETION TO IDENTIFY POSSIBLE TARGETS FOR THE DEVELOPMENT OF FUTURE THERAPIES FOR THESE CONDITIONS. ELUCIDATING THE ROLE OF EPIGENETICS IN THESE RESPIRATORY DISEASES MAY PROVIDE A BREATH OF FRESH AIR TO MILLIONS OF AFFECTED INDIVIDUALS AROUND THE WORLD. 2018 6 5539 30 ROLE OF CYSTIC FIBROSIS BRONCHIAL EPITHELIUM IN NEUTROPHIL CHEMOTAXIS. A HALLMARK OF CYSTIC FIBROSIS (CF) CHRONIC RESPIRATORY DISEASE IS AN EXTENSIVE NEUTROPHIL INFILTRATE IN THE MUCOSA FILLING THE BRONCHIAL LUMEN, STARTING EARLY IN LIFE FOR CF INFANTS. THE GENETIC DEFECT OF THE CF TRANSMEMBRANE CONDUCTANCE REGULATOR (CFTR) ION CHANNEL PROMOTES DEHYDRATION OF THE AIRWAY SURFACE LIQUID, ALTERS MUCUS PROPERTIES, AND DECREASES MUCOCILIARY CLEARANCE, FAVORING THE ONSET OF RECURRENT AND, ULTIMATELY, CHRONIC BACTERIAL INFECTION. NEUTROPHIL INFILTRATES ARE UNABLE TO CLEAR BACTERIAL INFECTION AND, AS AN ADVERSE EFFECT, CONTRIBUTE TO MUCOSAL TISSUE DAMAGE BY RELEASING PROTEASES AND REACTIVE OXYGEN SPECIES. MOREOVER, THE RAPID CELLULAR TURNOVER OF LUMENAL NEUTROPHILS RELEASES NUCLEIC ACIDS THAT FURTHER ALTER THE MUCUS VISCOSITY. A PROMINENT ROLE IN THE RECRUITMENT OF NEUTROPHIL IN BRONCHIAL MUCOSA IS PLAYED BY CF BRONCHIAL EPITHELIAL CELLS CARRYING THE DEFECTIVE CFTR PROTEIN AND ARE EXPOSED TO WHOLE BACTERIA AND BACTERIAL PRODUCTS, MAKING PHARMACOLOGICAL APPROACHES TO REGULATE THE EXAGGERATED NEUTROPHIL CHEMOTAXIS IN CF A RELEVANT THERAPEUTIC TARGET. HERE WE REVISE: (A) THE MAJOR RECEPTORS, KINASES, AND TRANSCRIPTION FACTORS LEADING TO THE EXPRESSION, AND RELEASE OF NEUTROPHIL CHEMOKINES IN BRONCHIAL EPITHELIAL CELLS; (B) THE ROLE OF INTRACELLULAR CALCIUM HOMEOSTASIS AND, IN PARTICULAR, THE CALCIUM CROSSTALK BETWEEN ENDOPLASMIC RETICULUM AND MITOCHONDRIA; (C) THE EPIGENETIC REGULATION OF THE KEY CHEMOKINES; (D) THE ROLE OF MUTANT CFTR PROTEIN AS A CO-REGULATOR OF CHEMOKINES TOGETHER WITH THE HOST-PATHOGEN INTERACTIONS; AND (E) DIFFERENT PHARMACOLOGICAL STRATEGIES TO REGULATE THE EXPRESSION OF CHEMOKINES IN CF BRONCHIAL EPITHELIAL CELLS THROUGH NOVEL DRUG DISCOVERY AND DRUG REPURPOSING. 2020 7 5585 32 ROLE OF OXIDATIVE STRESS AND GENETIC POLYMORPHISM OF MATRIX METALLOPROTEINASE-2 AND TISSUE INHIBITOR OF METALLOPROTEINASE-2 IN COPD. CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD), A COMPLAINT DESCRIBED BY PROGRESSIVE AND INADEQUATELY REVERSIBLE LIMITATION IN LUNGS WITH SYSTEMIC INFLAMMATION, IS LARGELY CURRENT IN INDIA. THERE'S NO REMEDY AVAILABLE SO FAR IT IS, THUS, IMPERATIVE TO UNDERSTAND THE UNDERPINNING PATHOGENESIS OF THE COMPLAINANT. A SET OF PROTEASES KNOWN AS MATRIX METALLOPROTEINASE (MMPS) ARE ESPECIALLY INVOLVED IN THE PROCESS OF ALVEOLAR DESTRUCTION AND MUCUS HYPERSECRETION. THERE ARE RESPONSIBLE FACTORS IN AN INHERITABLE POSITION TO CONTROL COPD LIKE MMPS AND TIMPS (TISSUE INHIBITOR OF METALLOPROTEINASES). MMPS DEGRADE EXTRACELLULAR MATRIX AND LEAD TO THE PATHOGENESIS OF COPD [1]. TIMPS PROTEINS THAT HELP TO INHIBIT THE MATRIX METALLOPROTEINASES. [2]. THIS REVIEW SUMMARIZES THE IMPLICIT PART OF CRUCIAL MMP-2 AND TIMP-2 IN COPD DISEASE. THOUGH THE CONCEPT SEEMS PROMISING, LIMITED KNOWLEDGE ABOUT THE EXACT FUNCTIONS OF A PARTICULAR MMP IN COPD AND THE COMPLICATIONS OF MMP IN SUBSTRATE AFFINITY MAKES THIS A GRUELING TASK. MMP2 AND TIMP2 BOTH ARE DIRECTLY OR INDIRECTLY REGULATED BY OXIDATIVE STRESS AND EPIGENETIC MECHANISM WHICH REGULATES THEIR EXPRESSIONS. COPD IS A SEDITIOUS RESPONSE TO FACTORS LIKE DUST, SMOKE, ETC., AND TRIGGERS EXTRA-PULMONARY GOODS WHICH CAUSE INFLAMMATION. [3]. THIS REVIEW EXPLAINS THE RELATIONSHIP BETWEEN MMP2 AND TIMP2 IN COPD PATIENTS WITH OXIDATIVE STRESS, ITS IMPACT ON COPD PATHOGENESIS, AND GENE EXPRESSION OF TIMP2 AND MMP2 WITH THEIR DOWNSTREAM EFFECTS. THIS ALSO GIVES SOME INSIGHTS INTO THERAPEUTIC INTERVENTIONS FOR TARGETING THESE ENZYMES. MMP2 AND TIMP2 BOTH PLAY A ROLE IN THE DEVELOPMENT OF COPD AND THEY NEED TO BE STUDIED WITH THE UTMOST FOCUS. 2023 8 3966 31 LONG NONCODING TRANSCRIPTOME IN CHRONIC OBSTRUCTIVE PULMONARY DISEASE. CHRONIC AIRWAY INFLAMMATION FROM RECURRING EXPOSURES TO NOXIOUS ENVIRONMENTAL STIMULI RESULTS IN A PROGRESSIVE AND IRREVERSIBLE AIRFLOW LIMITATION AND THE LUNG PARENCHYMAL DAMAGE THAT CHARACTERIZES CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD). THE LARGE VARIABILITY OBSERVED IN THE ONSET AND PROGRESSION OF COPD IS PRIMARILY DRIVEN BY COMPLEX GENE-ENVIRONMENT INTERACTIONS. THE TRANSCRIPTOMIC AND EPIGENETIC MEMORY POTENTIAL OF LUNG EPITHELIAL AND INNATE IMMUNE CELLS DRIVE RESPONSES, SUCH AS MUCUS HYPERREACTIVITY AND AIRWAY REMODELING, THAT ARE TIGHTLY REGULATED BY VARIOUS MOLECULAR MECHANISMS, FOR WHICH SEVERAL CANDIDATE SUSCEPTIBILITY GENES HAVE BEEN DESCRIBED. HOWEVER, THE RECENTLY DESCRIBED NONCODING RNA SPECIES, IN PARTICULAR THE LONG NONCODING RNAS, MAY ALSO HAVE AN IMPORTANT ROLE IN MODULATING PULMONARY RESPONSES TO CHRONIC INHALATION OF TOXIC SUBSTANCES AND THE DEVELOPMENT OF COPD. THIS REVIEW OUTLINES THE FEATURES OF LONG NONCODING RNAS THAT HAVE BEEN IMPLICATED IN REGULATING THE AIRWAY INFLAMMATORY RESPONSES TO CIGARETTE SMOKE EXPOSURE AND THEIR POSSIBLE ASSOCIATION WITH COPD PATHOGENESIS. AS COPD CONTINUES TO DEBILITATE THE INCREASINGLY AGING POPULATION AND CONTRIBUTE TO HIGHER MORBIDITY AND MORTALITY RATES WORLDWIDE, THE SEARCH FOR BETTER BIOMARKERS AND ALTERNATIVE THERAPEUTIC OPTIONS IS PIVOTAL. 2019 9 3711 27 INHALED DRUG DELIVERY FOR THE TARGETED TREATMENT OF ASTHMA. ASTHMA IS A CHRONIC LUNG DISEASE AFFECTING MILLIONS WORLDWIDE. WHILE CLASSICALLY ACKNOWLEDGED TO RESULT FROM ALLERGEN-DRIVEN TYPE 2 INFLAMMATORY RESPONSES LEADING TO IGE AND CYTOKINE PRODUCTION AND THE INFLUX OF IMMUNE CELLS SUCH AS MAST CELLS AND EOSINOPHILS, THE WIDE RANGE IN ASTHMATIC PATHOBIOLOGICAL SUBTYPES LEAD TO HIGHLY VARIABLE RESPONSES TO ANTI-INFLAMMATORY THERAPIES. THUS, THERE IS A NEED TO DEVELOP PATIENT-SPECIFIC THERAPIES CAPABLE OF ADDRESSING THE FULL SPECTRUM OF ASTHMATIC LUNG DISEASE. MOREOVER, DELIVERY OF TARGETED TREATMENTS FOR ASTHMA DIRECTLY TO THE LUNG MAY HELP TO MAXIMIZE THERAPEUTIC BENEFIT, BUT CHALLENGES REMAIN IN DESIGN OF EFFECTIVE FORMULATIONS FOR THE INHALED ROUTE. IN THIS REVIEW, WE DISCUSS THE CURRENT UNDERSTANDING OF ASTHMATIC DISEASE PROGRESSION AS WELL AS GENETIC AND EPIGENETIC DISEASE MODIFIERS ASSOCIATED WITH ASTHMA SEVERITY AND EXACERBATION OF DISEASE. WE ALSO OVERVIEW THE LIMITATIONS OF CLINICALLY AVAILABLE TREATMENTS FOR ASTHMA AND DISCUSS PRE-CLINICAL MODELS OF ASTHMA USED TO EVALUATE NEW THERAPIES. BASED ON THE SHORTCOMINGS OF EXISTING TREATMENTS, WE HIGHLIGHT RECENT ADVANCES AND NEW APPROACHES TO TREAT ASTHMA VIA INHALATION FOR MONOCLONAL ANTIBODY DELIVERY, MUCOLYTIC THERAPY TO TARGET AIRWAY MUCUS HYPERSECRETION AND GENE THERAPIES TO ADDRESS UNDERLYING DRIVERS OF DISEASE. FINALLY, WE CONCLUDE WITH DISCUSSION ON THE PROSPECTS FOR AN INHALED VACCINE TO PREVENT ASTHMA. 2023 10 4658 25 NEW ANTI-INFLAMMATORY TARGETS FOR CHRONIC OBSTRUCTIVE PULMONARY DISEASE. CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) IS ASSOCIATED WITH CHRONIC INFLAMMATION OF THE PERIPHERAL AIRWAYS AND LUNG PARENCHYMA, WHICH LEADS TO PROGRESSIVE OBSTRUCTION OF THE AIRWAYS. CURRENT MANAGEMENT WITH LONG-ACTING BRONCHODILATORS DOES NOT REDUCE DISEASE PROGRESSION, AND THERE ARE NO TREATMENTS THAT EFFECTIVELY SUPPRESS CHRONIC INFLAMMATION IN COPD. AN INCREASED UNDERSTANDING OF THE INFLAMMATORY PROCESSES THAT ARE INVOLVED IN THE PATHOPHYSIOLOGY OF COPD HAS IDENTIFIED SEVERAL NEW THERAPEUTIC TARGETS. THIS REVIEW DISCUSSES SOME OF THE MOST PROMISING OF THESE TARGETS, INCLUDING NEW ANTIOXIDANTS, KINASE INHIBITORS AND DRUGS THAT TARGET CELLULAR SENESCENCE, MICROBIAL COLONIZATION, EPIGENETIC REGULATION OF INFLAMMATORY GENE EXPRESSION AND CORTICOSTEROID RESISTANCE. 2013 11 1244 27 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 12 5411 29 REGULATION OF AIRWAY MUCIN GENE EXPRESSION. MUCINS ARE IMPORTANT COMPONENTS THAT EXERT A VARIETY OF FUNCTIONS IN CELL-CELL INTERACTION, EPIDERMAL GROWTH FACTOR RECEPTOR SIGNALING, AND AIRWAYS PROTECTION. IN THE CONDUCTING AIRWAYS OF THE LUNGS, MUCINS ARE THE MAJOR CONTRIBUTOR TO THE VISCOELASTIC PROPERTY OF MUCOUS SECRETION, WHICH IS THE MAJOR BARRIER TO TRAPPING INHALED MICROBIAL ORGANISM, PARTICULATES, AND OXIDATIVE POLLUTANTS. THE HOMEOSTASIS OF MUCIN PRODUCTION IS AN IMPORTANT FEATURE IN CONDUCTING AIRWAYS FOR THE MAINTENANCE OF MUCOCILIARY FUNCTION. ABERRANT MUCIN SECRETION AND ACCUMULATION IN AIRWAY LUMEN ARE CLINICAL HALLMARKS ASSOCIATED WITH VARIOUS LUNG DISEASES, SUCH AS ASTHMA, CHRONIC OBSTRUCTIVE PULMONARY DISEASE, CYSTIC FIBROSIS, EMPHYSEMA, AND LUNG CANCER. AMONG 20 KNOWN MUCIN GENES IDENTIFIED, 11 OF THEM HAVE BEEN VERIFIED AT EITHER THE MRNA AND/OR PROTEIN LEVEL IN AIRWAYS. THE REGULATION OF MUCIN GENES IS COMPLICATED, AS ARE THE MEDIATORS AND SIGNALING PATHWAYS. THIS REVIEW SUMMARIZES THE CURRENT VIEW ON THE MEDIATORS, THE SIGNALING PATHWAYS, AND THE TRANSCRIPTIONAL UNITS THAT ARE INVOLVED IN THE REGULATION OF AIRWAY MUCIN GENE EXPRESSION. IN ADDITION, WE ALSO POINT OUT ESSENTIAL FEATURES OF EPIGENETIC MECHANISMS FOR THE REGULATION OF THESE GENES. 2008 13 6687 24 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 14 2369 27 EPIGENETIC REGULATION OF T-HELPER CELL DIFFERENTIATION, MEMORY, AND PLASTICITY IN ALLERGIC ASTHMA. AN ESTIMATED 300 MILLION PEOPLE CURRENTLY SUFFER FROM ASTHMA, WHICH CAUSES APPROXIMATELY 250 000 DEATHS A YEAR. ALLERGEN-SPECIFIC T-HELPER (TH) CELLS PRODUCE CYTOKINES THAT INDUCE MANY OF THE HALLMARK FEATURES OF ASTHMA INCLUDING AIRWAYS HYPERREACTIVITY, EOSINOPHILIC AND NEUTROPHILIC INFLAMMATION, MUCUS HYPERSECRETION, AND AIRWAY REMODELING. CYTOKINE-PRODUCING TH SUBSETS INCLUDING TH1 (IFN-GAMMA), TH2 (IL-4, IL-5, IL-13), TH9 (IL-9), TH17 (IL-17), TH22 (IL-22), AND T REGULATORY (IL-10) CELLS HAVE ALL BEEN SUGGESTED TO PLAY A ROLE IN THE DEVELOPMENT OF ASTHMA. TH DIFFERENTIATION INVOLVES GENETIC REGULATION OF GENE EXPRESSION THROUGH THE CONCERTED ACTION OF CYTOKINES, TRANSCRIPTION FACTORS, AND EPIGENETIC REGULATORS. WE DESCRIBE HOW TH DIFFERENTIATION AND PLASTICITY IS REGULATED BY EPIGENETIC HISTONE AND DNA MODIFICATIONS, WITH A FOCUS ON THE REGULATION OF HISTONE METHYLATION BY MEMBERS OF THE POLYCOMB AND TRITHORAX COMPLEXES. IN ADDITION, WE OUTLINE ENVIRONMENTAL INFLUENCES THAT COULD INFLUENCE EPIGENETIC REGULATION OF TH CELLS AND DISCUSS THE POTENTIAL TO REGULATE TH PLASTICITY AND FUNCTION THROUGH DRUGS TARGETING THE EPIGENETIC MACHINERY. IT IS ALSO BECOMING APPARENT THAT EPIGENETIC REGULATION OF ALLERGEN-SPECIFIC MEMORY TH CELLS MAY BE IMPORTANT IN THE DEVELOPMENT AND PERSISTENCE OF CHRONIC ALLERGIES. FINALLY, WE DESCRIBE HOW EPIGENETIC MODIFIERS REGULATE CYTOKINE MEMORY IN TH CELLS AND DESCRIBE RECENTLY IDENTIFIED HYBRID, PLASTIC, AND PATHOGENIC MEMORY TH SUBSETS THE CONTEXT OF ALLERGIC ASTHMA. 2017 15 4953 27 PATHOGENESIS OF CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) INDUCED BY CIGARETTE SMOKE. CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) IS A COMMON RESPIRATORY DISEASE THAT IS CHARACTERIZED BY FUNCTIONAL AND STRUCTURAL ALTERATIONS PRIMARILY CAUSED BY LONG-TERM INHALATION OF HARMFUL PARTICLES. CIGARETTE SMOKE (CS) INDUCES AIRWAY INFLAMMATION IN COPD, WHICH IS KNOWN TO PERSIST EVEN AFTER SMOKING CESSATION. THIS REVIEW DISCUSSES THE BASIC PATHOGENESIS OF COPD, WITH PARTICULAR FOCUS ON AN ENDOGENOUS PROTECTIVE MECHANISM AGAINST OXIDATIVE STRESS VIA NRF2, ALTERED IMMUNE RESPONSE OF THE AIRWAY INFLAMMATORY CELLS, EXAGGERATED CELLULAR SENESCENCE OF THE LUNG STRUCTURAL CELLS, AND CELL DEATH WITH EXPANDED INFLAMMATION. RECENTLY, CS-INDUCED MITOCHONDRIA AUTOPHAGY IS REPORTED TO INITIATE PROGRAMMED NECROSIS (NECROPTOSIS). NECROPTOSIS IS A NEW CONCEPT OF CELL DEATH WHICH IS DRIVEN BY A DEFINED MOLECULAR PATHWAY ALONG WITH EXAGGERATED INFLAMMATION. THIS NEW CELL DEATH MECHANISM IS OF IMPORTANCE DUE TO ITS ABILITY TO PRODUCE MORE INFLAMMATORY SUBSTANCES DURING THE PROCESS OF EPITHELIAL DEATH, CONTRIBUTING TO PERSISTENT AIRWAY INFLAMMATION THAT CANNOT BE EXPLAINED BY APOPTOSIS-DERIVED CELL DEATH. AUTOPHAGY IS AN AUTO-CELL COMPONENT DEGRADATION SYSTEM EXECUTED BY LYSOSOMES THAT CONTROLS PROTEIN AND ORGANELLE DEGRADATION FOR SUCCESSFUL HOMEOSTASIS. AS WELL AS IN THE PROCESS OF NECROPTOSIS, AUTOPHAGY IS ALSO OBSERVED DURING CELLULAR SENESCENCE. AGING OF THE LUNGS RESULTS IN THE ACQUISITION OF SENESCENCE-ASSOCIATED SECRETORY PHENOTYPES (SASP) THAT ARE KNOWN TO SECRETE INFLAMMATORY CYTOKINES, CHEMOKINES, GROWTH FACTORS, AND MATRIX METALLOPROTEINASES RESULTING IN CHRONIC LOW-GRADE INFLAMMATION. IN FUTURE RESEARCH, WE INTEND TO HIGHLIGHT THE GENETIC AND EPIGENETIC APPROACHES THAT CAN FACILITATE THE UNDERSTANDING OF DISEASE SUSCEPTIBILITY. THE GOAL OF PRECISION MEDICINE IS TO ESTABLISH MORE ACCURATE DIAGNOSIS AND TREATMENT METHODS BASED ON THE PATIENT-SPECIFIC PATHOGENIC CHARACTERISTICS. THIS REVIEW PROVIDES INSIGHTS INTO CS-INDUCED COPD PATHOGENESIS, WHICH CONTRIBUTES TO A VERY COMPLEX DISEASE. INVESTIGATING THE MECHANISM OF DEVELOPING COPD, ALONG WITH THE AVAILABILITY OF THE PARTICULAR INHIBITORS, WILL LEAD TO NEW THERAPEUTIC APPROACHES IN COPD TREATMENT. 2019 16 1143 24 CONCISE REVIEW: CLINICAL PROSPECTS FOR TREATING CHRONIC OBSTRUCTIVE PULMONARY DISEASE WITH REGENERATIVE APPROACHES. CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) IS BECOMING A MAJOR CAUSE OF DEATH WORLDWIDE. COPD IS CHARACTERIZED BY A PROGRESSIVE AND NOT FULLY REVERSIBLE AIRFLOW LIMITATION CAUSED BY CHRONIC SMALL AIRWAY DISEASE AND LUNG PARENCHYMAL DESTRUCTION. CLINICALLY AVAILABLE DRUGS IMPROVE AIRFLOW OBSTRUCTION AND RESPIRATORY SYMPTOMS BUT CANNOT CURE THE DISEASE. SLOWING THE PROGRESSIVE LUNG DESTRUCTION OR REBUILDING THE DESTROYED LUNG STRUCTURE IS A PROMISING STRATEGY TO CURE COPD. IN CONTRAST TO SMALL ANIMAL MODELS, PHARMACOLOGICAL LUNG REGENERATION IS DIFFICULT IN HUMAN COPD. MATURATION, AGING, AND SENESCENCE IN COPD LUNG CELLS, INCLUDING ENDOGENOUS STEM CELLS, MAY AFFECT THE REGENERATIVE CAPACITY FOLLOWING PHARMACOLOGICAL THERAPY. THE LUNG IS A COMPLEX ORGAN COMPOSED OF MORE THAN 40 DIFFERENT CELL TYPES; THEREFORE, DETAILED ANALYSES, SUCH AS EPIGENETIC MODIFICATION ANALYSIS, IN EACH SPECIFIC CELL TYPE HAVE NOT BEEN PERFORMED IN LUNGS WITH COPD. RECENTLY, A METHOD FOR THE DIRECT ISOLATION OF INDIVIDUAL CELL TYPES FROM HUMAN LUNG HAS BEEN DEVELOPED, AND FINGERPRINTS OF EACH CELL TYPE IN COPD LUNGS CAN BE ANALYZED. RESEARCH USING THIS TECHNIQUE COMBINED WITH THE RECENTLY DISCOVERED LUNG ENDOGENOUS STEM-PROGENITOR POPULATIONS WILL GIVE A BETTER UNDERSTANDING ABOUT THE FATE OF COPD LUNG CELLS AND PROVIDE A FUTURE FOR CELL-BASED THERAPY TO TREAT THIS INTRACTABLE DISEASE. 2012 17 6005 29 THE AIRWAY EPITHELIUM-A CENTRAL PLAYER IN ASTHMA PATHOGENESIS. ASTHMA IS A CHRONIC INFLAMMATORY AIRWAY DISEASE CHARACTERIZED BY VARIABLE AIRFLOW OBSTRUCTION IN RESPONSE TO A WIDE RANGE OF EXOGENOUS STIMULI. THE AIRWAY EPITHELIUM IS THE FIRST LINE OF DEFENSE AND PLAYS AN IMPORTANT ROLE IN INITIATING HOST DEFENSE AND CONTROLLING IMMUNE RESPONSES. INDEED, INCREASING EVIDENCE INDICATES A RANGE OF ABNORMALITIES IN VARIOUS ASPECTS OF EPITHELIAL BARRIER FUNCTION IN ASTHMA. A CENTRAL PART OF THIS IMPAIRMENT IS A DISRUPTION OF THE AIRWAY EPITHELIAL LAYER, ALLOWING INHALED SUBSTANCES TO PASS MORE EASILY INTO THE SUBMUCOSA WHERE THEY MAY INTERACT WITH IMMUNE CELLS. FURTHERMORE, MANY OF THE IDENTIFIED SUSCEPTIBILITY GENES FOR ASTHMA ARE EXPRESSED IN THE AIRWAY EPITHELIUM. THIS REVIEW FOCUSES ON THE BIOLOGY OF THE AIRWAY EPITHELIUM IN HEALTH AND ITS PATHOBIOLOGY IN ASTHMA. WE WILL SPECIFICALLY DISCUSS EXTERNAL TRIGGERS SUCH AS ALLERGENS, VIRUSES AND ALARMINS AND THE EFFECT OF TYPE 2 INFLAMMATORY RESPONSES ON AIRWAY EPITHELIAL FUNCTION IN ASTHMA. WE WILL ALSO DISCUSS EPIGENETIC MECHANISMS RESPONDING TO EXTERNAL STIMULI ON THE LEVEL OF TRANSCRIPTIONAL AND POSTTRANSCRIPTIONAL REGULATION OF GENE EXPRESSION, AS WELL THE AIRWAY EPITHELIUM AS A POTENTIAL TREATMENT TARGET IN ASTHMA. 2020 18 6440 20 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 19 1245 26 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 20 3512 21 IDIOPATHIC PULMONARY FIBROSIS. IDIOPATHIC PULMONARY FIBROSIS IS A DEVASTATING, AGE-RELATED LUNG DISEASE OF UNKNOWN CAUSE THAT HAS FEW TREATMENT OPTIONS. THIS DISEASE WAS ONCE THOUGHT TO BE A CHRONIC INFLAMMATORY PROCESS, BUT CURRENT EVIDENCE INDICATES THAT THE FIBROTIC RESPONSE IS DRIVEN BY ABNORMALLY ACTIVATED ALVEOLAR EPITHELIAL CELLS (AECS). THESE CELLS PRODUCE MEDIATORS THAT INDUCE THE FORMATION OF FIBROBLAST AND MYOFIBROBLAST FOCI THROUGH THE PROLIFERATION OF RESIDENT MESENCHYMAL CELLS, ATTRACTION OF CIRCULATING FIBROCYTES, AND STIMULATION OF THE EPITHELIAL TO MESENCHYMAL TRANSITION. THE FIBROBLAST AND MYOFIBROBLAST FOCI SECRETE EXCESSIVE AMOUNTS OF EXTRACELLULAR MATRIX, MAINLY COLLAGENS, RESULTING IN SCARRING AND DESTRUCTION OF THE LUNG ARCHITECTURE. THE MECHANISMS THAT LINK IDIOPATHIC PULMONARY FIBROSIS WITH AGEING AND ABERRANT EPITHELIAL ACTIVATION ARE UNKNOWN; EVIDENCE SUGGESTS THAT THE ABNORMAL RECAPITULATION OF DEVELOPMENTAL PATHWAYS AND EPIGENETIC CHANGES HAVE A ROLE. IN THIS SEMINAR, WE REVIEW RECENT DATA ON THE CLINICAL COURSE, THERAPEUTIC OPTIONS, AND UNDERLYING MECHANISMS THOUGHT TO BE INVOLVED IN THE PATHOGENESIS OF IDIOPATHIC PULMONARY FIBROSIS. 2011