1 5769 130 SPECIFIC EPIGENETIC REGULATORS SERVE AS POTENTIAL THERAPEUTIC TARGETS IN IDIOPATHIC PULMONARY FIBROSIS. IDIOPATHIC PULMONARY FIBROSIS (IPF), A DISORDER OBSERVED MOSTLY IN OLDER HUMAN BEINGS, IS CHARACTERISED BY CHRONIC AND PROGRESSIVE LUNG SCARRING LEADING TO AN IRREVERSIBLE DECLINE IN LUNG FUNCTION. THIS HEALTH CONDITION HAS A DISMAL PROGNOSIS AND THE CURRENTLY AVAILABLE DRUGS ONLY DELAY BUT FAIL TO REVERSE THE PROGRESSION OF LUNG DAMAGE. CONSEQUENTLY, IT BECOMES IMPERATIVE TO DISCOVER IMPROVED THERAPEUTIC COMPOUNDS AND THEIR CELLULAR TARGETS TO CURE IPF. IN THIS REGARD, A NUMBER OF RECENT STUDIES HAVE TARGETED THE EPIGENETIC REGULATION BY HISTONE DEACETYLASES (HDACS) TO DEVELOP AND CATEGORISE ANTIFIBROTIC DRUGS FOR LUNGS. THEREFORE, THIS REVIEW FOCUSES ON HOW ABERRANT EXPRESSION OR ACTIVITY OF CLASSES I, II AND III HDACS ALTER TGF-BETA SIGNALLING TO PROMOTE EVENTS SUCH AS EPITHELIAL-MESENCHYMAL TRANSITION, DIFFERENTIATION OF ACTIVATED FIBROBLASTS INTO MYOFIBROBLASTS, AND EXCESS DEPOSITION OF THE EXTRACELLULAR MATRIX TO PROPEL LUNG FIBROSIS. FURTHER, THIS STUDY DESCRIBES HOW CERTAIN CHEMICAL COMPOUNDS OR DIETARY CHANGES MODULATE DYSREGULATED HDACS TO ATTENUATE FIVE FAULTY TGF-BETA-DEPENDENT PROFIBROTIC PROCESSES, BOTH IN ANIMAL MODELS AND CELL LINES REPLICATING IPF, THEREBY IDENTIFYING PROMISING MEANS TO TREAT THIS LUNG DISORDER. 2022 2 5575 37 ROLE OF MICRORNAS IN SIGNALING PATHWAYS ASSOCIATED WITH THE PATHOGENESIS OF IDIOPATHIC PULMONARY FIBROSIS: A FOCUS ON EPITHELIAL-MESENCHYMAL TRANSITION. IDIOPATHIC PULMONARY FIBROSIS (IPF) IS A CHRONIC AND PROGRESSIVE DISEASE WITH HIGH MORTALITY AND UNCLEAR ETIOLOGY. PREVIOUS EVIDENCE SUPPORTS THAT THE ORIGIN OF THIS DISEASE IS ASSOCIATED WITH EPIGENETIC ALTERATIONS, AGE, AND ENVIRONMENTAL FACTORS. IPF INITIATES WITH CHRONIC EPITHELIAL LUNG INJURIES, FOLLOWED BY BASAL MEMBRANE DESTRUCTION, WHICH PROMOTES THE ACTIVATION OF MYOFIBROBLASTS AND EXCESSIVE SYNTHESIS OF EXTRACELLULAR MATRIX (ECM) PROTEINS, AS WELL AS EPITHELIAL-MESENCHYMAL TRANSITION (EMT). DUE TO MIRNAS' ROLE AS REGULATORS OF APOPTOSIS, PROLIFERATION, DIFFERENTIATION, AND CELL-CELL INTERACTION PROCESSES, SOME STUDIES HAVE INVOLVED MIRNAS IN THE BIOGENESIS AND PROGRESSION OF IPF. IN THIS CONTEXT, THE ANALYSIS AND DISCUSSION OF THE PROBABLE ASSOCIATION OF MIRNAS WITH THE SIGNALING PATHWAYS INVOLVED IN THE DEVELOPMENT OF IPF WOULD IMPROVE OUR KNOWLEDGE OF THE ASSOCIATED MOLECULAR MECHANISMS, THEREBY FACILITATING ITS EVALUATION AS A THERAPEUTIC TARGET FOR THIS SEVERE LUNG DISEASE. IN THIS WORK, THE MOST RECENT PUBLICATIONS EVALUATING THE ROLE OF MIRNAS AS REGULATORS OR ACTIVATORS OF SIGNAL PATHWAYS ASSOCIATED WITH THE PATHOGENESIS OF IPF WERE ANALYZED. THE SEARCH IN PUBMED WAS MADE USING THE FOLLOWING TERMS: "MIRNAS AND IDIOPATHIC PULMONARY FIBROSIS (IPF)"; "MIRNAS AND IPF AND SIGNALING PATHWAYS (SP)"; AND "MIRNAS AND IPF AND SP AND IPF PATHOGENESIS". ADDITIONALLY, WE FOCUS MAINLY ON THOSE WORKS WHERE THE SIGNALING PATHWAYS INVOLVED WITH EMT, FIBROBLAST DIFFERENTIATION, AND SYNTHESIS OF ECM COMPONENTS WERE ASSESSED. FINALLY, THE IMPORTANCE AND SIGNIFICANCE OF MIRNAS AS POTENTIAL THERAPEUTIC OR DIAGNOSTIC TOOLS FOR THE TREATMENT OF IPF ARE DISCUSSED. 2022 3 6223 40 THE LEADING ROLE OF EPITHELIAL CELLS IN THE PATHOGENESIS OF IDIOPATHIC PULMONARY FIBROSIS. IDIOPATHIC PULMONARY FIBROSIS (IPF) IS A RELENTLESSLY PROGRESSIVE AND DEVASTATING INTERSTITIAL LUNG DISEASE OF UNKNOWN ETIOLOGY, WHERE THE NORMAL LUNG ARCHITECTURE IS LOST AND REPLACED BY FIBROTIC TISSUE LEADING TO AN IRREVERSIBLE AND PROGRESSIVE RESPIRATORY INSUFFICIENCY. HISTORICALLY, IPF WAS CONSIDERED A CHRONIC INFLAMMATORY DISORDER, WHICH GRADUALLY PROGRESSED TO ESTABLISHED FIBROSIS. HOWEVER, STRONG CLINICAL AND EXPERIMENTAL EVIDENCE INDICATES THAT THE DISEASE REPRESENTS AN EPITHELIAL-DRIVEN DISORDER WHICH RESULTS FROM A COMPLEX INTERPLAY OF GENETIC AND ENVIRONMENTAL RISK FACTORS, AGING-ASSOCIATED PROCESSES AND A PROFIBROTIC EPIGENETIC REPROGRAMMING. THE CONVERGENCE OF THESE FACTORS RESULTS IN THE ABERRANT ACTIVATION OF EPITHELIAL CELLS THAT INITIATE THE DEVELOPMENT OF THE DISEASE, PRODUCING VIRTUALLY ALL THE MEDIATORS THAT PARTICIPATE IN THE MIGRATION, PROLIFERATION AND ACTIVATION OF FIBROBLASTS, THEIR DIFFERENTIATION TO MYOFIBROBLASTS AND THE EXCESSIVE AND CHAOTIC SECRETION OF EXTRACELLULAR MATRIX PROTEINS. ALTHOUGH PROGRESS HAS BEEN MADE IN UNDERSTANDING THE CAUSES AND CONSEQUENCES OF THIS ABNORMAL BEHAVIOR OF DISTAL AIRWAYS AND ALVEOLAR EPITHELIUM, THE MECHANISMS THAT INITIATE AND PERPETUATE THE VICIOUS CIRCLE OF MULTIDIRECTIONAL ABNORMAL COMMUNICATIONS BETWEEN THE EPITHELIUM AND FIBROBLASTS AND OTHER RESIDENT CELLS HAVE NOT BEEN ELUCIDATED. IN THIS REVIEW, WE DISCUSS THE ROLE OF EPITHELIAL CELLS AND THE MECHANISMS UNDERLYING THE FIBROTIC RESPONSE IN IPF, AND HIGHLIGHT SOME PROMISING THERAPEUTIC TARGETS FOR THESE CELLS. 2020 4 4294 39 MICRORNA REGULATORY NETWORKS IN IDIOPATHIC PULMONARY FIBROSIS. IDIOPATHIC PULMONARY FIBROSIS (IPF) IS A CHRONIC, PROGRESSIVE, AND FATAL SCARRING LUNG DISEASE OF UNKNOWN ETIOLOGY, CHARACTERIZED BY CHANGES IN MICRORNA EXPRESSION. ACTIVATION OF TRANSFORMING GROWTH FACTOR (TGF-BETA) IS A KEY EVENT IN THE DEVELOPMENT OF IPF. RECENT REPORTS HAVE ALSO IDENTIFIED EPIGENETIC MODIFICATION AS AN IMPORTANT PLAYER IN THE PATHOGENESIS OF IPF. IN THIS REVIEW, WE SUMMARIZE THE MAIN RESULTS OF STUDIES THAT ADDRESS THE ROLE OF MICRORNAS IN IPF AND HIGHLIGHT THE SYNERGISTIC ACTIONS OF THESE MICRORNAS IN REGULATING TGF-BETA, THE PRIMARY FIBROGENIC MEDIATOR. WE OUTLINE EPIGENETIC REGULATION OF MICRORNAS BY METHYLATION. FUNCTIONAL STUDIES IDENTIFY MICRORNAS THAT ALTER PROLIFERATIVE AND MIGRATORY PROPERTIES OF FIBROBLASTS, AND INDUCE PHENOTYPIC CHANGES IN EPITHELIAL CELLS CONSISTENT WITH EPITHELIAL-MESENCHYMAL TRANSITION. THOUGH THESE STUDIES WERE PERFORMED IN ISOLATION, WE IDENTIFY MULTIPLE CO-OPERATIVE ACTIONS AFTER ASSEMBLING THE RESULTS INTO A NETWORK. CONSTRUCTION OF SUCH NETWORKS WILL HELP IDENTIFY DISEASE-PROPELLING HUBS THAT CAN BE TARGETED FOR THERAPEUTIC PURPOSES. 2015 5 4038 24 MACROPHAGE IMPLICATION IN IPF: UPDATES ON IMMUNE, EPIGENETIC, AND METABOLIC PATHWAYS. IDIOPATHIC PULMONARY FIBROSIS (IPF) IS A LETHAL INTERSTITIAL LUNG DISEASE OF UNKNOWN ETIOLOGY WITH A POOR PROGNOSIS. IT IS A CHRONIC AND PROGRESSIVE DISEASE THAT HAS A DISTINCT RADIOLOGICAL AND PATHOLOGICAL PATTERN FROM COMMON INTERSTITIAL PNEUMONIA. THE USE OF IMMUNOSUPPRESSIVE MEDICATION WAS SHOWN TO BE COMPLETELY INEFFECTIVE IN CLINICAL TRIALS, RESULTING IN YEARS OF NEGLECT OF THE IMMUNE COMPONENT. HOWEVER, RECENT DEVELOPMENTS IN FUNDAMENTAL AND TRANSLATIONAL SCIENCE DEMONSTRATE THAT IMMUNE CELLS PLAY A SIGNIFICANT REGULATORY ROLE IN IPF, AND MACROPHAGES APPEAR TO BE AMONG THE MOST CRUCIAL. THESE HIGHLY PLASTIC CELLS GENERATE MULTIPLE GROWTH FACTORS AND MEDIATORS THAT HIGHLY AFFECT THE INITIATION AND PROGRESSION OF IPF. IN THIS REVIEW, WE WILL PROVIDE AN UPDATE ON THE ROLE OF MACROPHAGES IN IPF THROUGH A SYSTEMIC DISCUSSION OF VARIOUS REGULATORY MECHANISMS INVOLVING IMMUNE RECEPTORS, CYTOKINES, METABOLISM, AND EPIGENETICS. 2023 6 3674 33 INFLAMMATION AND DYSREGULATED FIBROBLAST PROLIFERATION--NEW MECHANISMS? IDIOPATHIC PULMONARY FIBROSIS (IPF) IS A DEVASTATING, AGE-RELATED LUNG DISEASE OF UNKNOWN CAUSE THAT HAS FEW TREATMENT OPTIONS. ONCE THOUGHT TO BE A CHRONIC INFLAMMATORY PROCESS, CURRENT EVIDENCE INDICATES THAT THE FIBROTIC RESPONSE MAY PRIMARILY BE DRIVEN BY ABNORMALLY ACTIVATED ALVEOLAR EPITHELIAL CELLS AND THE UNDERLYING MESENCHYME. THE MEDIATORS PRODUCED AND PRESENT IN THIS MICROENVIRONMENT INDUCE THE FORMATION OF FIBROBLAST FOCI THROUGH THE PROLIFERATION OF RESIDENT MESENCHYMAL CELLS, ATTRACTION OF CIRCULATING FIBROCYTES, AND STIMULATION OF 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 DETAILED MECHANISMS THAT LINK IPF WITH AGEING AND ABERRANT EPITHELIAL ACTIVATION ARE UNKNOWN, BUT SOME EVIDENCE SUGGESTS THAT THE ABNORMAL RECAPITULATION OF DEVELOPMENTAL PATHWAYS AND EPIGENETIC CHANGES MAY PLAY A ROLE. THIS REVIEW PROVIDES A BRIEF SYNOPSIS OF HIGHLIGHTS IN THE CURRENT UNDERSTANDING OF THE PATHOPHYSIOLOGY OF IPF, AS WELL AS NOVEL THERAPEUTICS BEING EXPLORED IN CLINICAL TRIALS FOR THE TREATMENT OF THIS DEVASTATING DISEASE. 2013 7 2933 38 GENESIS OF THE MYOFIBROBLAST IN LUNG INJURY AND FIBROSIS. TISSUE INJURY INCITES A REPAIR RESPONSE WITH A KEY MESENCHYMAL COMPONENT THAT PROVIDES THE ESSENTIAL CONNECTIVE TISSUE FOR SUBSEQUENT REGENERATION OR PATHOLOGICAL FIBROSIS. THE FIBROBLAST IS THE MAJOR MESENCHYMAL CELL TYPE TO BE IMPLICATED IN THIS CONNECTIVE TISSUE RESPONSE, AND IT IS IN ITS ACTIVATED OR DIFFERENTIATED FORM THAT IT PARTICIPATES IN THE REPAIR PROCESS. THE MYOFIBROBLAST REPRESENTS SUCH AN ACTIVATED MESENCHYMAL CELL AND IS A KEY SOURCE OF EXTRACELLULAR MATRIX AND INFLAMMATORY/FIBROGENIC CYTOKINES AS WELL AS PARTICIPATING IN WOUND CONTRACTION. ALTHOUGH SUCCESSFUL HEALING RESULTS IN GRADUAL DISAPPEARANCE OF MYOFIBROBLASTS, THEIR PERSISTENCE IS ASSOCIATED WITH CHRONIC AND PROGRESSIVE FIBROSIS. THUS, ELUCIDATION OF THE MECHANISM INVOLVED IN THE GENESIS OF THE MYOFIBROBLAST SHOULD PROVIDE INSIGHT INTO BOTH PATHOGENESIS OF CHRONIC FIBROTIC DISEASES AND THERAPEUTIC STRATEGIES FOR THEIR MANAGEMENT AND CONTROL. ALTHOUGH THE FIBROBLAST IS A WELL-DOCUMENTED PROGENITOR CELL FOR THE MYOFIBROBLAST, RECENT STUDIES HAVE SUGGESTED ADDITIONAL PRECURSOR CELLS THAT HAVE THE POTENTIAL TO GIVE RISE TO THE MYOFIBROBLAST. MANY OF THE STUDIES FOCUSED ON MECHANISMS AND FACTORS THAT REGULATE INDUCTION OF ALPHA-SMOOTH MUSCLE ACTIN EXPRESSION, A KEY AND COMMONLY USED MARKER OF THE MYOFIBROBLAST. THESE REVEAL COMPLEX AND MULTIFACTORIAL MECHANISMS INVOLVING TRANSCRIPTIONAL AND EPIGENETIC REGULATION AND IMPLICATING DIVERSE CELL-SIGNALING PATHWAYS, INCLUDING THOSE ACTIVATED BY THE POTENT FIBROGENIC CYTOKINE TRANSFORMING GROWTH FACTOR BETA. DESPITE THESE EXTENSIVE STUDIES, MANY ASPECTS REMAIN POORLY UNDERSTOOD, WITH THE SUGGESTION THAT ADDITIONAL NOVEL MECHANISMS REMAIN TO BE DISCOVERED. FUTURE STUDIES WITH THE HELP OF NEWLY DEVELOPED TECHNICAL ADVANCEMENTS SHOULD EXPEDITE DISCOVERY IN THIS DIRECTION. 2012 8 4480 37 MOLECULAR PATHWAYS AND ROLE OF EPIGENETICS IN THE IDIOPATHIC PULMONARY FIBROSIS. IDIOPATHIC PULMONARY FIBROSIS (IPF) IS A FATAL LUNG DISEASE WITH UNKNOWN ETIOLOGICAL FACTORS THAT CAN PROGRESS TO OTHER DANGEROUS DISEASES LIKE LUNG CANCER. ENVIRONMENTAL AND GENETIC PREDISPOSITION ARE THE TWO MAJOR ETIOLOGICAL OR RISK FACTORS INVOLVED IN THE PATHOLOGY OF THE IPF. AMONG THE ENVIRONMENTAL RISK FACTORS, SMOKING IS ONE OF THE MAJOR CAUSES FOR THE DEVELOPMENT OF IPF. EPIGENETIC PATHWAYS LIKE NUCLEOSOMES REMODELING, DNA METHYLATION, HISTONE MODIFICATIONS AND MIRNA MEDIATED GENES PLAY A CRUCIAL ROLE IN DEVELOPMENT OF IPF. MUTATIONS IN THE GENES MAKE THE EPIGENETIC FACTORS AS IMPORTANT DRUG TARGETS IN IPF. TRANSCRIPTIONAL CHANGES DUE TO ENVIRONMENTAL FACTORS ARE ALSO INVOLVED IN THE PROGRESSION OF IPF. THE MUTATIONS IN HUMAN TELOMERASE REVERSE TRANSCRIPTASE (HTERT) HAVE SHOWN DECREASED LIFE EXPECTANCY IN IPF PATIENTS. THE TERT-GENE IS HIGHLY EXPRESSED IN CHRONIC SMOKERS AND MAKES THE ROLE OF EPIGENETICS EVIDENT. DRUG LIKE NINTEDANIB ACTS THROUGH VASCULAR ENDOTHELIAL GROWTH FACTOR RECEPTORS (VEGFR), WHILE DRUG PIRFENIDONE ACTS THROUGH TRANSFORMING GROWTH FACTOR (TGF), WHICH IS USEFUL IN IPF. GEFITINIB, A TYROSINE KINASE INHIBITOR OF EGFR, IS USEFUL AS AN ANTI-FIBROSIS AGENT IN PRECLINICAL MODELS. NEWER DRUGS SUCH AS CELGENE-CC90001 AND FIBROGEN-FG-3019 ARE CURRENTLY UNDER INVESTIGATIONS ACTS THROUGH THE MODULATING EPIGENETIC MECHANISMS. THUS, THE STUDY ON EPIGENETICS OPENS A WIDE WINDOW FOR THE DISCOVERY OF NEWER DRUGS. THIS STUDY PROVIDES AN ELEMENTARY ANALYSIS OF MULTIPLE REGULATORS OF EPIGENETICS AND THEIR ROLES ASSOCIATED WITH THE PATHOLOGY OF IPF. FURTHER, THIS REVIEW ALSO INCLUDES EPIGENETIC DRUGS UNDER DEVELOPMENT IN PRECLINICAL AND CLINICAL STAGES. 2022 9 6212 28 THE INTERPLAY OF THE GENETIC ARCHITECTURE, AGING, AND ENVIRONMENTAL FACTORS IN THE PATHOGENESIS OF IDIOPATHIC PULMONARY FIBROSIS. IDIOPATHIC PULMONARY FIBROSIS (IPF) IS A CHRONIC FIBROSING LUNG DISEASE OF INDETERMINATE ETIOLOGY AND LIMITED THERAPEUTIC OPTIONS. THE INITIATION, DEVELOPMENT, AND PROGRESSION OF IPF ARE INFLUENCED BY GENETIC PREDISPOSITION, AGING, AND HOST AND ENVIRONMENTAL FACTORS, BUT THE MAGNITUDE OF THE CONTRIBUTION OF EACH OF THEM AND THE SEQUENCE OF THE PATHOGENIC EVENTS ARE UNCERTAIN. CURRENT EVIDENCE INDICATES THAT ACCUMULATED ENVIRONMENTAL EXPOSURES IN A GENETICALLY PREDISPOSED INDIVIDUAL, USUALLY OVER 60 YEARS OF AGE, LEADS TO PHENOTYPIC AND FUNCTIONAL ALTERATIONS OF THE LUNG EPITHELIUM. ABERRANT ACTIVATION OF EPITHELIAL CELLS RESULTS, THROUGH A COMPLEX RELEASE OF NUMEROUS MEDIATORS, IN THE LOCAL EXPANSION OF PECULIAR SUBSETS OF AGGRESSIVE FIBROBLASTS AND MYOFIBROBLASTS, WHICH ARE CRUCIAL EFFECTOR CELLS OF FIBROTIC REMODELING AND LOSS OF THE NORMAL LUNG ARCHITECTURE AND FUNCTION. PROGRESSIVE INCREASE OF THE MECHANICAL STIFFNESS ACTIVATES CELL-AUTONOMOUS AND MATRIX-DEPENDENT PROCESSES CONTRIBUTING TO THE PERPETUATION OF THE FIBROTIC RESPONSE. THIS PERSPECTIVE PROVIDES AN INTEGRAL OVERVIEW OF THE MAJOR RISK FACTORS UNDERPINNING THE PATHOGENESIS OF IPF, INCLUDING GENE VARIANTS, AGING ALTERATIONS, ENVIRONMENTAL FACTORS, HOST RISK FACTORS, AND EPIGENETIC REPROGRAMMING. 2021 10 4575 34 MYOFIBROBLASTS. PURPOSE OF REVIEW: INTEREST IN THE MYOFIBROBLAST AS A KEY PLAYER IN PROPAGATION OF CHRONIC PROGRESSIVE FIBROSIS CONTINUES TO ELICIT MANY PUBLICATIONS, WITH FOCUS ON ITS CELLULAR ORIGINS AND THE MECHANISMS UNDERPINNING THEIR DIFFERENTIATION AND/OR TRANSITION. THE OBJECTIVE OF THE REVIEW IS TO HIGHLIGHT THIS RECENT PROGRESS. RECENT FINDINGS: THE EPITHELIAL ORIGIN OF THE MYOFIBROBLAST IN FIBROSIS HAS BEEN CHALLENGED BY RECENT STUDIES, WITH THE PERICYTE SUGGESTED AS A POSSIBLE PRECURSOR INSTEAD. ADDITIONAL SIGNALING PATHWAYS, INCLUDING NOTCH, WNT, AND HEDGEHOG, ARE IMPLICATED IN MYOFIBROBLAST DIFFERENTIATION. THE IMPORTANCE OF NADPH OXIDASE 4 WAS HIGHLIGHTED RECENTLY TO SUGGEST A POTENTIAL LINK BETWEEN CELLULAR/OXIDATIVE STRESS AND THE GENESIS OF THE MYOFIBROBLAST. RECENT OBSERVATIONS ON THE IMPORTANCE OF LYSOPHOSPHATIDIC ACID IN FIBROSIS SUGGEST THAT THIS MAY BE DUE, IN PART, TO ITS ABILITY TO REGULATE MYOFIBROBLAST DIFFERENTIATION. FINALLY, THERE IS INCREASING EVIDENCE FOR THE ROLE OF EPIGENETIC MECHANISMS IN REGULATING MYOFIBROBLAST DIFFERENTIATION, INCLUDING DNA METHYLATION AND MIRNA REGULATION OF GENE EXPRESSION. SUMMARY: THESE RECENT DISCOVERIES OPEN UP A WHOLE NEW ARRAY OF POTENTIAL TARGETS FOR NOVEL ANTIFIBROTIC THERAPIES. THIS IS OF SPECIAL IMPORTANCE GIVEN THE CURRENT BLEAK OUTLOOK FOR CHRONIC PROGRESSIVE FIBROTIC DISEASES, SUCH AS SCLERODERMA, DUE TO LACK OF EFFECTIVE THERAPIES. 2013 11 5805 43 STRATEGIES TO PREVENT AND REVERSE LIVER FIBROSIS IN HUMANS AND LABORATORY ANIMALS. LIVER FIBROSIS RESULTS FROM CHRONIC DAMAGE TO THE LIVER IN CONJUNCTION WITH VARIOUS PATHWAYS AND IS MEDIATED BY A COMPLEX MICROENVIRONMENT. BASED ON CLINICAL OBSERVATIONS, IT IS NOW EVIDENT THAT FIBROSIS IS A DYNAMIC, BIDIRECTIONAL PROCESS WITH AN INHERENT CAPACITY FOR RECOVERY AND REMODELING. THE MAJOR MECHANISMS INVOLVED IN LIVER FIBROSIS INCLUDE THE REPETITIVE INJURY OF HEPATOCYTES, THE ACTIVATION OF THE INFLAMMATORY RESPONSE AFTER INJURY STIMULATION, AND THE ACTIVATION AND PROLIFERATION OF HEPATIC STELLATE CELLS (HSCS), WHICH REPRESENTS THE MAJOR EXTRACELLULAR MATRIX (ECM)-PRODUCING CELLS, STIMULATED BY HEPATOCYTE INJURY AND INFLAMMATION. THE MICROENVIRONMENT IN THE LIVER IS SYNERGISTICALLY REGULATED ABNORMAL ECM DEPOSITION, SCAR FORMATION, ANGIOGENESIS, AND FIBROGENESIS. MOREOVER, RECENT STUDIES HAVE CLARIFIED NOVEL MECHANISM IN FIBROSIS SUCH AS EPIGENETIC REGULATION OF HSCS, THE LEPTIN AND PPARGAMMA PATHWAYS, THE COAGULATION SYSTEM, AND EVEN AUTOPHAGY. UNCOVERING THE MECHANISMS OF LIVER FIBROGENESIS PROVIDES A BASIS TO DEVELOP POTENTIAL THERAPIES TO REVERSE AND TREAT THE FIBROTIC RESPONSE, THEREBY IMPROVING THE OUTCOMES OF PATIENTS WITH CHRONIC LIVER DISEASE. ALTHOUGH BOTH SCIENTIFIC AND CLINICAL CHALLENGES REMAIN, EMERGING STUDIES ATTEMPT TO REVEAL THE IDEAL ANTI-FIBROTIC DRUG THAT COULD BE EASILY DELIVERED TO THE LIVER WITH HIGH SPECIFICITY AND LOW TOXICITY. THIS REVIEW HIGHLIGHTS THE MECHANISMS, INCLUDING NOVEL PATHWAYS UNDERLYING FIBROGENESIS THAT MAY BE TRANSLATED INTO PREVENTIVE AND TREATMENT STRATEGIES, REVIEWS BOTH CURRENT AND NOVEL AGENTS THAT TARGET SPECIFIC PATHWAYS OR MULTIPLE TARGETS, AND DISCUSSES NOVEL DRUG DELIVERY SYSTEMS SUCH AS NANOTECHNOLOGY THAT CAN BE APPLIED IN THE TREATMENT OF LIVER FIBROSIS. IN ADDITION, WE ALSO DISCUSS SOME CURRENT TREATMENT STRATEGIES THAT ARE BEING APPLIED IN ANIMAL MODELS AND IN CLINICAL TRIALS. 2015 12 4450 37 MOLECULAR MECHANISMS AND CELLULAR CONTRIBUTION FROM LUNG FIBROSIS TO LUNG CANCER DEVELOPMENT. IDIOPATHIC PULMONARY FIBROSIS (IPF) IS A CHRONIC, PROGRESSIVE, FIBROSING INTERSTITIAL LUNG DISEASE (ILD) OF UNKNOWN AETIOLOGY, WITH A MEDIAN SURVIVAL OF 2-4 YEARS FROM THE TIME OF DIAGNOSIS. ALTHOUGH IPF HAS UNKNOWN AETIOLOGY BY DEFINITION, THERE HAVE BEEN IDENTIFIED SEVERAL RISKS FACTORS INCREASING THE PROBABILITY OF THE ONSET AND PROGRESSION OF THE DISEASE IN IPF PATIENTS SUCH AS CIGARETTE SMOKING AND ENVIRONMENTAL RISK FACTORS ASSOCIATED WITH DOMESTIC AND OCCUPATIONAL EXPOSURE. AMONG THEM, CIGARETTE SMOKING TOGETHER WITH CONCOMITANT EMPHYSEMA MIGHT PREDISPOSE IPF PATIENTS TO LUNG CANCER (LC), MOSTLY TO NON-SMALL CELL LUNG CANCER (NSCLC), INCREASING THE RISK OF LUNG CANCER DEVELOPMENT. TO THIS PURPOSE, IPF AND LC SHARE SEVERAL CELLULAR AND MOLECULAR PROCESSES DRIVING THE PROGRESSION OF BOTH PATHOLOGIES SUCH AS FIBROBLAST TRANSITION PROLIFERATION AND ACTIVATION, ENDOPLASMIC RETICULUM STRESS, OXIDATIVE STRESS, AND MANY GENETIC AND EPIGENETIC MARKERS THAT PREDISPOSE IPF PATIENTS TO LC DEVELOPMENT. NINTEDANIB, A TYROSINE-KINASE INHIBITOR, WAS FIRSTLY DEVELOPED AS AN ANTICANCER DRUG AND THEN RECOGNIZED AS AN ANTI-FIBROTIC AGENT BASED ON THE COMMON TARGET MOLECULAR PATHWAY. IN THIS REVIEW OUR AIM IS TO DESCRIBE THE UPDATED STUDIES ON COMMON CELLULAR AND MOLECULAR MECHANISMS BETWEEN IPF AND LUNG CANCER, KNOWLEDGE OF WHICH MIGHT HELP TO FIND NOVEL THERAPEUTIC TARGETS FOR THIS DISEASE COMBINATION. 2021 13 1255 28 CURRENT STATUS OF NOVEL ANTIFIBROTIC THERAPIES IN PATIENTS WITH CHRONIC LIVER DISEASE. FIBROSIS ACCUMULATION IS A DYNAMIC PROCESS RESULTING FROM A WOUND-HEALING RESPONSE TO ACUTE OR CHRONIC LIVER INJURY OF ALL CAUSES. THE CASCADE STARTS WITH HEPATOCYTE NECROSIS AND APOPTOSIS, WHICH INSTIGATE INFLAMMATORY SIGNALING BY CHEMOKINES AND CYTOKINES, RECRUITMENT OF IMMUNE CELL POPULATIONS, AND ACTIVATION OF FIBROGENIC CELLS, CULMINATING IN THE DEPOSITION OF EXTRACELLULAR MATRIX. THESE KEY ELEMENTS, ALONG WITH PATHWAYS OF TRANSCRIPTIONAL AND EPIGENETIC REGULATION, REPRESENT FERTILE THERAPEUTIC TARGETS. NEW THERAPIES INCLUDE DRUGS SPECIFICALLY DESIGNED AS ANTIFIBROTICS, AS WELL AS DRUGS ALREADY AVAILABLE WITH WELL-ESTABLISHED SAFETY PROFILES, WHOSE MECHANISM OF ACTION MAY ALSO BE ANTIFIBROTIC. AT THE SAME TIME, THE DEVELOPMENT OF NONINVASIVE FIBROGENIC MARKERS, AND TECHNIQUES (E.G. FIBROSCAN), AS WELL AS COMBINED SCORING SYSTEMS INCORPORATING SERUM AND CLINICAL FEATURES WILL ALLOW IMPROVED ASSESSMENT OF THERAPY RESPONSE. IN AGGREGATE, THE ADVANCES IN THE ELUCIDATION OF THE BIOLOGY OF FIBROSIS, COMBINED WITH IMPROVED TECHNOLOGIES FOR ASSESSMENT WILL PROVIDE A COMPREHENSIVE FRAMEWORK FOR DESIGN OF ANTIFIBROTICS AND THEIR ANALYSIS IN WELL-DESIGNED CLINICAL TRIALS. THESE EFFORTS MAY ULTIMATELY YIELD SUCCESS IN HALTING THE PROGRESSION OF, OR REVERSING, LIVER FIBROSIS. 2011 14 2169 35 EPIGENETIC MECHANISMS IN PARENCHYMAL LUNG DISEASES: BYSTANDERS OR THERAPEUTIC TARGETS? EPIGENETIC RESPONSES DUE TO ENVIRONMENTAL CHANGES ALTER CHROMATIN STRUCTURE, WHICH IN TURN MODIFIES THE PHENOTYPE, GENE EXPRESSION PROFILE, AND ACTIVITY OF EACH CELL TYPE THAT HAS A ROLE IN THE PATHOPHYSIOLOGY OF A DISEASE. PULMONARY DISEASES ARE ONE OF THE MAJOR CAUSES OF DEATH IN THE WORLD, INCLUDING LUNG CANCER, IDIOPATHIC PULMONARY FIBROSIS (IPF), CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD), PULMONARY HYPERTENSION (PH), LUNG TUBERCULOSIS, PULMONARY EMBOLISM, AND ASTHMA. SEVERAL LINES OF EVIDENCE INDICATE THAT EPIGENETIC MODIFICATIONS MAY BE ONE OF THE MAIN FACTORS TO EXPLAIN THE INCREASING INCIDENCE AND PREVALENCE OF LUNG DISEASES INCLUDING IPF AND COPD. INTERESTINGLY, ISOLATED FIBROBLASTS AND SMOOTH MUSCLE CELLS FROM PATIENTS WITH PULMONARY DISEASES SUCH AS IPF AND PH THAT WERE CULTURED EX VIVO MAINTAINED THE DISEASE PHENOTYPE. THE CELLS OFTEN SHOW A HYPER-PROLIFERATIVE, APOPTOSIS-RESISTANT PHENOTYPE WITH INCREASED EXPRESSION OF EXTRACELLULAR MATRIX (ECM) AND ACTIVATED FOCAL ADHESIONS SUGGESTING THE PRESENCE OF AN EPIGENETICALLY IMPRINTED PHENOTYPE. MOREOVER, MANY ABNORMALITIES OBSERVED IN MOLECULAR PROCESSES IN IPF PATIENTS ARE SHOWN TO BE EPIGENETICALLY REGULATED, SUCH AS INNATE IMMUNITY, CELLULAR SENESCENCE, AND APOPTOTIC CELL DEATH. DNA METHYLATION, HISTONE MODIFICATION, AND MICRORNA REGULATION CONSTITUTE THE MOST COMMON EPIGENETIC MODIFICATION MECHANISMS. 2022 15 1597 35 DNA METHYLATION REGULATED GENE EXPRESSION IN ORGAN FIBROSIS. DNA METHYLATION IS A MAJOR EPIGENETIC MECHANISM TO REGULATE GENE EXPRESSION. EPIGENETIC REGULATION, INCLUDING DNA METHYLATION, HISTONE MODIFICATIONS AND RNA INTERFERENCE, RESULTS IN HERITABLE CHANGES IN GENE EXPRESSION INDEPENDENT OF ALTERATIONS IN DNA SEQUENCE. EPIGENETIC REGULATION OFTEN OCCURS IN RESPONSE TO AGING AND ENVIRONMENT STIMULI, INCLUDING EXPOSURES AND DIET. STUDIES HAVE SHOWN THAT DNA METHYLATION IS CRITICAL IN THE PATHOGENESIS OF FIBROSIS INVOLVING MULTIPLE ORGAN SYSTEMS, CONTRIBUTING TO SIGNIFICANT MORBIDITY AND MORTALITY. ABERRANT DNA METHYLATION CAN SILENCE OR ACTIVATE GENE EXPRESSION PATTERNS THAT DRIVE THE FIBROSIS PROCESS. FIBROSIS IS A PATHOLOGICAL WOUND HEALING PROCESS IN RESPONSE TO CHRONIC INJURY. IT IS CHARACTERIZED BY EXCESSIVE EXTRACELLULAR MATRIX PRODUCTION AND ACCUMULATION, WHICH EVENTUALLY AFFECTS ORGAN ARCHITECTURE AND RESULTS IN ORGAN FAILURE. FIBROSIS CAN AFFECT A WIDE RANGE OF ORGANS, INCLUDING THE HEART AND LUNGS, AND HAVE LIMITED THERAPEUTIC OPTIONS. DNA METHYLATION, LIKE OTHER EPIGENETIC PROCESS, IS REVERSIBLE, THEREFORE REGARDED AS ATTRACTIVE THERAPEUTIC INTERVENTIONS. ALTHOUGH EPIGENETIC MECHANISMS ARE HIGHLY INTERACTIVE AND OFTEN REINFORCING, THIS REVIEW DISCUSSES DNA METHYLATION-DEPENDENT MECHANISMS IN THE PATHOGENESIS OF ORGAN FIBROSIS, WITH FOCUS ON CARDIAC AND PULMONARY FIBROSIS. WE DISCUSS SPECIFIC PRO- AND ANTI-FIBROTIC GENES AND PATHWAYS REGULATED BY DNA METHYLATION IN ORGAN FIBROSIS; WE FURTHER HIGHLIGHT THE POTENTIAL BENEFITS AND SIDE-EFFECTS OF EPIGENETIC THERAPIES IN FIBROTIC DISORDERS. 2017 16 1113 35 COMMON PATHWAYS IN IDIOPATHIC PULMONARY FIBROSIS AND CANCER. IDIOPATHIC PULMONARY FIBROSIS (IPF) IS MARKED BY A VERY DISAPPOINTING SURVIVAL RATE AND STILL REPRESENTS A CLINICAL DILEMMA. ACCORDING TO THE CURRENT PATHOGENIC HYPOTHESIS, CHRONIC DAMAGE OF THE ALVEOLAR EPITHELIUM IS FOLLOWED BY ABNORMAL TISSUE REPAIR AND IMPAIRMENT OF THE ALVEOLAR STRUCTURE. THIS PROCESS IS DRIVEN BY PATHOGENIC EVENTS VERY SIMILAR TO CANCER, INCLUDING EPIGENETIC AND GENETIC CHANGES, ALTERED RESPONSE TO REGULATORY SIGNALS, ABNORMAL EXPRESSION OF MICRORNAS AND ACTIVATION OF SPECIFIC SIGNALLING PATHWAYS. IPF ALSO RESEMBLES CANCER WITH REGARD TO ITS POOR RESPONSE TO MEDICAL TREATMENT AND PROGNOSIS, WHICH IS VERY OFTEN WORSE THAN MANY CANCERS. WE HAVE HYPOTHESISED THAT IPF MIGHT BE ASSIMILATED TO A NEOPROLIFERATIVE DISORDER OF THE LUNG. VIEWING IPF AS A CANCER-LIKE DISEASE MAY SATISFY THE NEED FOR A BETTER UNDERSTANDING OF THE PATHOGENESIS OF IPF BY EXPLOITING THE LARGE AMOUNT OF KNOWLEDGE THAT CANCER BIOLOGY EVOKES. THE RECOGNITION OF COMMON PATHOGENIC PATHWAYS BETWEEN THE TWO DISEASES MAY STIMULATE NEW CLINICAL TRIALS WITH CANCER DRUGS, DIFFERENT DRUG COMBINATIONS AND DIFFERENT LINES OF DRUGS, AS ALREADY EXPERIMENTED IN ONCOLOGY. MOREOVER, THE CONCEPT OF IPF AS A CANCER-LIKE DISORDER MAY IMPROVE THE ATTENTION GIVEN TO THIS DREADFUL DISEASE ON A PUBLIC, POLITICAL AND HEALTHCARE LEVEL. 2013 17 4463 40 MOLECULAR MECHANISMS OF HISTONE DEACETYLASES AND INHIBITORS IN RENAL FIBROSIS PROGRESSION. RENAL FIBROSIS IS A COMMON PROGRESSIVE MANIFESTATION OF CHRONIC KIDNEY DISEASE. THIS PHENOMENON OF SELF-REPAIR IN RESPONSE TO KIDNEY DAMAGE SERIOUSLY AFFECTS THE NORMAL FILTRATION FUNCTION OF THE KIDNEY. YET, THERE ARE NO SPECIFIC TREATMENTS FOR THE CONDITION, WHICH MARKS FIBROSIS AS AN IRREVERSIBLE PATHOLOGICAL SEQUELA. AS SUCH, THERE IS A PRESSING NEED TO IMPROVE OUR UNDERSTANDING OF HOW FIBROSIS DEVELOPS AT THE CELLULAR AND MOLECULAR LEVELS AND EXPLORE SPECIFIC TARGETED THERAPIES FOR THESE PATHOGENIC MECHANISMS. IT IS NOW GENERALLY ACCEPTED THAT RENAL FIBROSIS IS A PATHOLOGICAL TRANSITION MEDIATED BY EXTRACELLULAR MATRIX (ECM) DEPOSITION, ABNORMAL ACTIVATION OF MYOFIBROBLASTS, AND EPITHELIAL-MESENCHYMAL TRANSITION (EMT) OF RENAL TUBULAR EPITHELIAL CELLS UNDER THE REGULATION OF TGF-BETA. HISTONE DEACETYLASES (HDACS) APPEAR TO PLAY AN ESSENTIAL ROLE IN PROMOTING RENAL FIBROSIS THROUGH NON-HISTONE EPIGENETIC MODIFICATIONS. IN THIS REVIEW, WE SUMMARIZE THE MECHANISMS OF RENAL FIBROSIS AND THE SIGNALING PATHWAYS THAT MIGHT BE INVOLVED IN HDACS IN RENAL FIBROSIS, AND THE SPECIFIC MECHANISMS OF ACTION OF VARIOUS HDAC INHIBITORS (HDACI) IN THE ANTI-FIBROTIC PROCESS TO ELUCIDATE HDACI AS A NOVEL THERAPEUTIC TOOL TO SLOW DOWN THE PROGRESSION OF RENAL FIBROSIS. 2022 18 2381 29 EPIGENETIC REGULATION OF WOUND HEALING AND FIBROSIS. PURPOSE OF REVIEW: WOUND HEALING IS A NORMAL PHYSIOLOGICAL RESPONSE TO TISSUE INJURY WHICH CAN OCCUR IN ANY ORGAN. MECHANISMS THAT ORCHESTRATE WOUND HEALING IN DIFFERENT ORGANS ARE SURPRISINGLY GENERIC, INVOLVING GENERATION OF FIBROBLASTS AND MYOFIBROBLASTS BY DIFFERENTIATION PROCESSES THAT REQUIRE EXTENSIVE ALTERATIONS IN GENE EXPRESSION. THIS PROCESS AND INDEED PHENOTYPE OF CELLS ARE ORCHESTRATED BY THE COMBINED INFLUENCES OF MOLECULAR COMPONENTS OF EPIGENOME INCLUDING DNA METHYLATION, VAST ARRAY OF POSTTRANSLATIONAL MODIFICATIONS OF THE HISTONE PROTEIN CONSTITUENTS OF CHROMATIN AND REGULATORY NONCODING RNAS OF WHICH MICRORNAS (MIRS) ARE THE MOST EXTENSIVELY STUDIED. RECENT FINDINGS: NUMEROUS STUDIES FROM THE LAST 12 MONTHS SHOW ALL THE THREE EPIGENETIC MECHANISMS TO BE REGULATING GENERATION AND APOPTOSIS OF MYOFIBROBLASTS IN ORGANS AFFECTED BY PERTURBED WOUND HEALING. FURTHERMORE, THESE MECHANISMS ARE INVOLVED IN FIBROTIC DISEASE ITSELF, WITH SOME MIRS AND EPIGENETIC DRUGS BEING TESTED FOR THEIR THERAPEUTIC POTENTIAL. SUMMARY: FIELDS OF WOUND HEALING AND FIBROSIS WILL BE ENRICHED OVER THE NEXT DECADE BY PLETHORA OF NEW INFORMATION REGARDING EPIGENETIC CONTROL MECHANISMS WHICH WILL HOPEFULLY PROVIDE NEW ADVANCES IN DIAGNOSTICS AND PROGNOSTICS. WITH THE DESIGN OF EVER MORE SPECIFIC EPIGENETIC DRUGS, WE MAY IMPROVE OUR ABILITY TO THERAPEUTICALLY OPTIMIZE WOUND HEALING AND PREVENT FIBROSIS IN CHRONIC DISEASE AND AGEING. 2013 19 4738 32 NOVEL FIBROBLAST PHENOTYPES IN HOMEOSTASIS AND CHRONIC INFLAMMATION: FROM FUNCTIONS TO POTENTIAL REGULATORS. FIBROBLASTS ARE ESSENTIAL COMPONENTS OF THE STROMA, SUSTAINING A VARIETY OF TISSUES AND BEING KEY TO THE PROCESS OF TISSUE REPAIR AFTER INJURY. THEIR ROLE IN TISSUE REPAIR HAS BEEN ATTRIBUTED TO THEIR ABILITY TO ACQUIRE A CONTRACTILE, EXTRACELLULAR MATRIX-PRODUCING PHENOTYPE KNOWN AS MYOFIBROBLASTS. THIS PROPERTY IS PRIMARILY DEPENDENT ON THEIR RESPONSE TO THE PLEIOTROPIC CYTOKINE TRANSFORMING GROWTH FACTOR-BETA1. UNTIL RECENTLY, THE POTENTIAL ROLE OF FIBROBLASTS IN OTHER HOMEOSTATIC AND DISEASE-RELATED PROCESSES WAS LESS WELL UNDERSTOOD. ALTHOUGH IN VITRO STUDIES INDICATED THAT FIBROBLASTS ARE ABLE TO RESPOND TO AND SECRETE INFLAMMATORY MEDIATORS, DEFINITIVE EVIDENCE OF THEIR CONTRIBUTION TO CHRONIC INFLAMMATION WAS LIMITED. HOWEVER, THE EMERGENCE OF TECHNIQUES THAT ALLOW EXPLORATION OF TISSUES AT THE SINGLE CELL LEVEL HAS CHALLENGED THE PREVIOUS PARADIGMS ON FIBROBLAST IDENTITY AND FUNCTIONS, AND HAS LED TO THE DISCOVERY OF SIGNIFICANT DIVERSITY, SHOWING THE PRESENCE OF FIBROBLASTS WITH ALTERNATE TRANSCRIPTIONAL PROFILES IN A VARIETY OF TISSUES. THESE STUDIES HAVE ALSO SUGGESTED POTENTIAL ROLES OF NOVEL FIBROBLAST SUBTYPES AS REGULATORS OF EPITHELIAL HOMEOSTASIS AND RENEWAL, INFLAMMATORY CELL INFILTRATION AND ACTIVATION, AND ANTIGEN PRESENTATION. HERE, WE PROVIDE A COMPREHENSIVE REVIEW OF THE RECENT LITERATURE ON FIBROBLAST DIVERSITY IN THE DIGESTIVE TRACT, SKIN, LUNGS AND JOINTS. WE ALSO REVIEW EVIDENCE OF THEIR CONTRIBUTION TO THE REGULATION OF HOMEOSTASIS AND CHRONIC INFLAMMATION, AS WELL AS THEIR INTERACTIONS WITH OTHER CELLS IN VARIOUS TISSUE COMPARTMENTS. WE DISCUSS EVIDENCE OF DIFFERENT FACTORS INVOLVED IN THE CONTROL OF FIBROBLAST FUNCTION, ADDRESSING THE ROLE OF VARIOUS CYTOKINES, TRANSCRIPTION FACTORS AND EPIGENETIC CHANGES, AS WELL AS MICROENVIRONMENTAL FACTORS, INCLUDING EXTRACELLULAR MATRIX STIFFNESS, HYPOXIA, AND METABOLIC SHIFTS. 2023 20 5026 39 PERSONALIZED MEDICINE IN IDIOPATHIC PULMONARY FIBROSIS: FACTS AND PROMISES. PURPOSE OF REVIEW: IN THIS ARTICLE, WE SUMMARIZE AND DISCUSS THE MOST RECENT LITERATURE ON PERSONALIZED MEDICINE IN IDIOPATHIC PULMONARY FIBROSIS (IPF), A CHRONIC PROGRESSIVE AND ALMOST INVARIABLY LETHAL DISEASE OF UNKNOWN CAUSE. THIS REVIEW IS TIMELY AS MAJOR ADVANCES IN OUR UNDERSTANDING OF DISEASE PATHOBIOLOGY AND IMPROVEMENTS IN MOLECULAR TECHNIQUES HAVE RECENTLY LED TO THE IDENTIFICATION OF POTENTIAL SURROGATES OF DIAGNOSIS, PROGNOSIS AND RESPONSE TO TREATMENT. RECENT FINDINGS: THE MOST PROMISING AND ADVANCED CANDIDATE BIOMARKERS ARE PRESENTED BASED ON THEIR PROPOSED MECHANISTIC PATHWAYS (E.G. ALVEOLAR EPITHELIAL CELL DYSFUNCTION, IMMUNE DYSREGULATION, MICROBIOME, EXTRACELLULAR MATRIX REMODELING AND FIBROPROLIFERATION, EPIGENETIC MARKERS AND METABOLOMICS). RECENT DATA SUGGEST THAT COMPONENTS OF THE IMMUNE SYSTEM MAY CONTRIBUTE TO THE DEVELOPMENT OF IPF. A POTENTIAL ROLE FOR INFECTIONS AS A COFACTOR IN DISEASE DEVELOPMENT AND PROGRESSION OR AS A TRIGGER IN DISEASE EXACERBATION HAS ALSO RECENTLY BEEN PROPOSED. SUMMARY: CLINICAL MANAGEMENT OF IPF IS UNSATISFACTORY BECAUSE OF LIMITED AVAILABILITY OF TRULY EFFECTIVE THERAPIES, LACK OF ACCURATE PREDICTORS OF DISEASE BEHAVIOR AND ABSENCE OF SIMPLE SHORT-TERM MEASURES OF THERAPEUTIC RESPONSE. A NUMBER OF PUTATIVE BIOMARKERS HAVE BEEN IDENTIFIED IN PATIENTS WITH IPF, ALTHOUGH NONE HAS BEEN VALIDATED TO THE STANDARD NECESSARY FOR THEIR USE IN EITHER THERAPEUTIC TRIALS OR CLINICAL PRACTICE. CURRENTLY, ONGOING PROSPECTIVE LONGITUDINAL STUDIES WILL HOPEFULLY PERMIT SUCH VALIDATION. 2015