1 1510 142 DNA METHYLATION AND NONCODING RNA IN OA: RECENT FINDINGS AND METHODOLOGICAL ADVANCES. INTRODUCTION: OSTEOARTHRITIS (OA) IS A CHRONIC MUSCULOSKELETAL DISEASE CHARACTERIZED BY PROGRESSIVE LOSS OF JOINT FUNCTION. HISTORICALLY, IT HAS BEEN CHARACTERIZED AS A DISEASE CAUSED BY MECHANICAL TRAUMA, SO-CALLED 'WEAR AND TEAR'. OVER THE PAST TWO DECADES, IT HAS COME TO BE UNDERSTOOD AS A COMPLEX SYSTEMIC DISORDER INVOLVING GENE-ENVIRONMENTAL INTERACTIONS. EPIGENETIC CHANGES HAVE BEEN INCREASINGLY IMPLICATED. RECENT IMPROVEMENTS IN MICROARRAY AND NEXT-GENERATION SEQUENCING (NGS) TECHNOLOGIES HAVE ALLOWED FOR EVER MORE COMPLEX EVALUATIONS OF EPIGENETIC ABERRATIONS ASSOCIATED WITH THE DEVELOPMENT AND PROGRESSION OF OA. METHODS: A SYSTEMATIC REVIEW WAS CONDUCTED IN THE PUBMED DATABASE. WE CURATED STUDIES THAT PRESENTED THE RESULTS OF DNA METHYLATION AND NONCODING RNA RESEARCH IN HUMAN OA AND OA ANIMAL MODELS SINCE 1985. RESULTS: HEREIN, WE DISCUSS RECENT FINDINGS AND METHODOLOGICAL ADVANCEMENTS IN OA EPIGENETICS, INCLUDING A DISCUSSION OF DNA METHYLATION, INCLUDING MICROARRAY AND NGS STUDIES, AND NONCODING RNAS. BEYOND CARTILAGE, WE ALSO HIGHLIGHT STUDIES IN SUBCHONDRAL BONE AND PERIPHERAL BLOOD MONONUCLEAR CELLS, WHICH HIGHLIGHT WIDESPREAD AND POTENTIALLY CLINICALLY IMPORTANT ALTERATIONS IN EPIGENETIC PATTERNS SEEN IN OA PATIENTS. FINALLY, WE DISCUSS EPIGENETIC EDITING APPROACHES IN THE CONTEXT OF OA. CONCLUSIONS: ALTHOUGH A SUBSTANTIAL BODY OF LITERATURE HAS ALREADY BEEN PUBLISHED IN OA, MUCH IS STILL UNKNOWN. FUTURE OA EPIGENETICS STUDIES WILL NO DOUBT CONTINUE TO BROADEN OUR UNDERSTANDING OF UNDERLYING PATHOPHYSIOLOGY AND PERHAPS OFFER NOVEL DIAGNOSTICS AND/OR TREATMENTS FOR HUMAN OA. 2021 2 3038 41 GENOME ENGINEERING FOR OSTEOARTHRITIS: FROM DESIGNER CELLS TO DISEASE-MODIFYING DRUGS. BACKGROUND: OSTEOARTHRITIS (OA) IS A HIGHLY PREVALENT DEGENERATIVE JOINT DISEASE INVOLVING JOINT CARTILAGE AND ITS SURROUNDING TISSUES. OA IS THE LEADING CAUSE OF PAIN AND DISABILITY WORLDWIDE. AT PRESENT, THERE ARE NO DISEASE-MODIFYING OA DRUGS, AND THE PRIMARY THERAPIES INCLUDE EXERCISE AND NONSTEROIDAL ANTI-INFLAMMATORY DRUGS UNTIL TOTAL JOINT REPLACEMENT AT THE END-STAGE OF THE DISEASE. METHODS: IN THIS REVIEW, WE SUMMARIZED THE CURRENT STATE OF KNOWLEDGE IN GENETIC AND EPIGENETIC ASSOCIATIONS AND RISK FACTORS FOR OA AND THEIR POTENTIAL DIAGNOSTIC AND THERAPEUTIC APPLICATIONS. RESULTS: GENOME-WIDE ASSOCIATION STUDIES AND ANALYSIS OF EPIGENETIC MODIFICATIONS (SUCH AS MIRNA EXPRESSION, DNA METHYLATION AND HISTONE MODIFICATIONS) CONDUCTED ACROSS VARIOUS POPULATIONS SUPPORT THE NOTION THAT THERE IS A GENETIC BASIS FOR CERTAIN SUBSETS OF OA PATHOGENESIS. CONCLUSION: WITH RECENT ADVANCES IN THE DEVELOPMENT OF GENOME EDITING TECHNOLOGIES SUCH AS THE CRISPR-CAS9 SYSTEM, THESE GENETIC AND EPIGENETIC ALTERNATIONS IN OA CAN BE USED AS PLATFORMS FROM WHICH POTENTIAL BIOMARKERS FOR THE DIAGNOSIS, PROGNOSIS, DRUG RESPONSE, AND DEVELOPMENT OF POTENTIAL PERSONALIZED THERAPEUTIC TARGETS FOR OA CAN BE APPROACHED. FURTHERMORE, GENOME EDITING HAS ALLOWED THE DEVELOPMENT OF "DESIGNER" CELLS, WHEREBY THE RECEPTORS, GENE REGULATORY NETWORKS, OR TRANSGENES CAN BE MODIFIED AS A BASIS FOR NEW CELL-BASED THERAPIES. 2019 3 3108 32 GENOMICS OF PAIN IN OSTEOARTHRITIS. OSTEOARTHRITIS (OA) ACCOUNTS FOR THE MAJORITY OF THE DISEASE BURDEN FOR MUSCULOSKELETAL DISORDERS AND IS ONE OF THE LEADING CAUSES OF DISABILITY WORLDWIDE. THIS DISABILITY IS THE RESULT NOT OF THE CARTILAGE LOSS THAT DEFINES OA RADIOGRAPHICALLY, BUT OF THE CHRONIC PAIN WHOSE PRESENCE DEFINES SYMPTOMATIC OA. IT IS BECOMING CLEAR THAT MANY GENES, EACH WITH A SMALL EFFECT SIZE, CONTRIBUTE TO THE RISK OF DEVELOPING OA. HOWEVER, THE GENETICS OF OA PAIN ARE ONLY JUST STARTING TO BE EXPLORED. THIS REVIEW WILL DESCRIBE THE FIRST GENES TO HAVE BEEN IDENTIFIED IN GENOMIC STUDIES OF OA PAIN, AS WELL AS THE POSSIBLE DUAL ROLES OF GENES PREVIOUSLY IDENTIFIED IN GENOMIC STUDIES OF OA IN THE CONTEXT OF PAIN. DIFFICULTIES ASSOCIATED WITH ATTEMPTING TO CHARACTERISE THE GENETICS OF OA PAIN WILL BE DISCUSSED AND PROMISING FUTURE AVENUES OF RESEARCH INTO GENETIC AND EPIGENETIC FACTORS AFFECTING OA PAIN DESCRIBED. 2013 4 2017 45 EPIGENETIC BIOMARKERS IN RHEUMATOLOGY - THE FUTURE? EPIGENETIC CHANGES ARE STABLE MODIFICATIONS OF DNA OR HISTONES THAT PROFOUNDLY ALTER GENE EXPRESSION. THEY CAN BE CHANGED BY ENVIRONMENTAL INFLUENCES AND CAN THEN BE PASSED ON TO DAUGHTER CELLS OR VIA THE GERM LINE TO OFFSPRING. A VARIETY OF CHANGES IN EPIGENETIC MARKS AND IN THE EXPRESSION OF NONCODING RNA HAS BEEN FOUND IN CANCER AS WELL AS IN CHRONIC INFLAMMATORY DISEASES. INTERESTINGLY, IN BOTH DISEASES SIMILAR MECHANISMS AND PATHWAYS ARE AFFECTED ALBEIT OFTEN TO A DIFFERENT EXTENT. DNA METHYLATION IS OFTEN LOST IN REPETITIVE SEQUENCES, WHILE IN PROMOTER REGIONS HYPO- AS WELL AS HYPERMETHYLATION IS FOUND. CHANGES IN MICRORNA LEVELS TYPICALLY AFFECT MICRORNAS THAT ARE CHANGED BY AN INFLAMMATORY ENVIRONMENT, BUT DISEASE SPECIFIC CHANGES HAVE ALSO BEEN FOUND IN THE BLOOD AND VARIOUS CELL TYPES OF PATIENTS WITH RHEUMATOID ARTHRITIS, SYSTEMIC LUPUS ERYTHEMATOSUS AND OTHER RHEUMATIC DISEASES. THEREFORE, CHANGES IN THE EXPRESSION OF MICRORNA IN PARTICULAR, BUT ALSO DEMETHYLATED GENE LOCI, HAVE BEEN PROPOSED AS POTENTIAL BIOMARKERS IN CHRONIC INFLAMMATORY DISEASES AND IN CANCER. POTENTIALLY, THESE CHANGES COULD BE USED FOR EARLY DIAGNOSIS AND ALSO TO PREDICT TREATMENT RESPONSE. UNFORTUNATELY MOST STUDIES IN RHEUMATOLOGY UP TO NOW WERE NOT DESIGNED TO VALIDATE THESE EPIGENETIC CHANGES AS BIOMARKERS. SINCE THE CANCER FIELD IS MUCH MORE ADVANCED IN THE USAGE OF BIOMARKERS FOR DISEASE SUBCLASSIFICATIONS AND SUBSEQUENT THERAPEUTIC DECISIONS, IT IS WORTHWHILE TO TAKE A CLOSER LOOK AT THE BIOMARKERS, METHODS AND PROCEDURES USED IN ONCOLOGY AND TO SEE WHICH OF THESE COULD ALSO BE APPLIED TO PREDICTING DISEASE SEVERITY AND THERAPEUTIC RESPONSE IN RHEUMATIC DISEASES. THIS ARTICLE WILL HIGHLIGHT COMMON EPIGENETIC PATHWAYS ACTIVATED IN CANCER AND VARIOUS RHEUMATIC DISEASES AND SUMMARISE EPIGENETIC CHANGES THAT HAVE THE POTENTIAL TO BECOME BIOMARKERS IN RHEUMATIC DISEASES. 2016 5 1522 46 DNA METHYLATION CHANGE PROFILING OF COLORECTAL DISEASE: SCREENING TOWARDS CLINICAL USE. COLON CANCER REMAINS ONE OF THE LEADING CAUSES OF CANCER-RELATED DEATHS WORLDWIDE. TRANSFORMATION OF COLON EPITHELIAL CELLS INTO INVASIVE ADENOCARCINOMAS HAS BEEN WELL KNOWN TO BE DUE TO THE ACCUMULATION OF MULTIPLE GENETIC AND EPIGENETIC CHANGES. IN THE PAST DECADE, THE ETIOLOGY OF INFLAMMATORY BOWEL DISEASE (IBD) WHICH IS CHARACTERIZED BY CHRONIC INFLAMMATION OF THE INTESTINAL MUCOSA, WAS ONLY PARTIALLY EXPLAINED BY GENETIC STUDIES PROVIDING SUSCEPTIBILITY LOCI, BUT RECENTLY EPIGENETIC STUDIES HAVE PROVIDED CRITICAL EVIDENCES AFFECTING IBD PATHOGENESIS. OVER THE PAST DECADE, A DEEP UNDERSTANDING OF EPIGENETICS ALONG WITH TECHNOLOGICAL ADVANCES HAVE LED TO IDENTIFYING NUMEROUS GENES THAT ARE REGULATED BY PROMOTER DNA HYPERMETHYLATION IN COLORECTAL DISEASES. RECENT ADVANCES IN OUR UNDERSTANDING OF THE ROLE OF DNA METHYLATION IN COLORECTAL DISEASES COULD IMPROVE A MULTITUDE OF POWERFUL DNA METHYLATION-BASED BIOMARKERS, PARTICULARLY FOR USE AS DIAGNOSIS, PROGNOSIS, AND PREDICTION FOR THERAPEUTIC APPROACHES. THIS REVIEW FOCUSES ON THE EMERGING POTENTIAL FOR TRANSLATIONAL RESEARCH OF EPIGENETIC ALTERATIONS INTO CLINICAL UTILITY AS MOLECULAR BIOMARKERS. MOREOVER, THIS REVIEW DISCUSSES RECENT PROGRESS REGARDING THE IDENTIFICATION OF UNKNOWN HYPERMETHYLATED GENES IN COLON CANCERS AND IBD, AS WELL AS THEIR POSSIBLE ROLE IN CLINICAL PRACTICE, WHICH WILL HAVE IMPORTANT CLINICAL SIGNIFICANCE, PARTICULARLY IN THE ERA OF THE PERSONALIZED MEDICINE. 2021 6 6676 37 USING EPIGENETIC TOOLS TO INVESTIGATE ANTIDEPRESSANT RESPONSE. MAJOR DEPRESSIVE DISORDER IS A CHRONIC AND DEBILITATING ILLNESS. IT IS MOST COMMONLY TREATED WITH ANTIDEPRESSANT DRUGS, HOWEVER, AS THE MAJORITY OF PATIENTS DO NOT RESPOND ON THEIR FIRST TRIAL OR FOLLOWING SEVERAL ADEQUATE TRIALS, THERE IS GREAT INTEREST IN IDENTIFYING BIOLOGICAL FACTORS THAT MAY HELP SELECT THE MOST APPROPRIATE TREATMENT FOR EACH PATIENT AND IN UNDERSTANDING BIOLOGICAL PROCESSES THAT MEDIATE TREATMENT RESPONSE. EPIGENETIC FACTORS, SUCH AS NON-CODING RNAS (NCRNAS), HOLD POTENTIAL AS BIOMARKERS OF ANTIDEPRESSANT RESPONSE. IN THIS CHAPTER, WE REVIEW KEY METHODOLOGICAL CONSIDERATIONS WHEN INVESTIGATING NCRNA BIOMARKERS, INCLUDING BIOLOGICAL SAMPLES AND TECHNOLOGIES WHICH HAVE BEEN USED IN THESE STUDIES. SECONDLY, WE SUMMARIZE FINDINGS FROM STUDIES INVESTIGATING NCRNAS IN ANTIDEPRESSANT TREATMENT RESPONSE. FINALLY, WE DISCUSS SOME OF THE FUTURE DIRECTIONS WHICH WILL BE NECESSARY FOR THE DEVELOPMENT OF CLINICALLY RELEVANT EPIGENETIC TOOLS. 2018 7 2232 40 EPIGENETIC MODIFICATIONS OF MIRNAS IN OSTEOARTHRITIS: A SYSTEMATIC REVIEW ON THEIR METHYLATION LEVELS AND EFFECTS ON CHONDROCYTES, EXTRACELLULAR MATRIX AND JOINT INFLAMMATION. OSTEOARTHRITIS (OA) IS A JOINT DISORDER CHARACTERIZED BY PROGRESSIVE DEGENERATION OF CARTILAGE EXTRACELLULAR MATRIX (ECM), CHONDROCYTE HYPERTROPHY AND APOPTOSIS AND INFLAMMATION. THE CURRENT TREATMENTS MAINLY CONCERN PAIN CONTROL AND REDUCTION OF INFLAMMATION, BUT NO THERAPEUTIC STRATEGY HAS BEEN IDENTIFIED AS A DISEASE-MODIFYING TREATMENT. THEREFORE, IDENTIFYING SPECIFIC BIOMARKERS USEFUL TO PREVENT, TREAT OR DISTINGUISH THE STAGES OF OA DISEASE HAS BECOME AN IMMEDIATE NEED OF CLINICAL PRACTICE. THE ROLE OF MICRORNAS (MIRNAS) IN OA HAS BEEN INVESTIGATED IN THE LAST DECADE, AND INCREASING EVIDENCE HAS EMERGED THAT THE INFLUENCE OF THE ENVIRONMENT ON GENE EXPRESSION THROUGH EPIGENETIC PROCESSES CONTRIBUTES TO THE DEVELOPMENT, PROGRESSION AND AGGRESSIVENESS OF OA, IN PARTICULAR ACTING ON THE MICROENVIRONMENT MODULATIONS. THE EFFECTS OF EPIGENETIC REGULATION, PARTICULARLY DIFFERENT MIRNA METHYLATION DURING OA DISEASE, WERE HIGHLIGHTED IN THE PRESENT SYSTEMATIC REVIEW. THE EVIDENCE ARISING FROM THIS STUDY OF THE LITERATURE CONDUCTED IN THREE DATABASES (PUBMED, SCOPUS, WEB OF SCIENCE) SUGGESTED THAT MIRNA METHYLATION STATE ALREADY STRONGLY IMPACTS OA PROGRESSION, DRIVING CHONDROCYTES AND SYNOVIOCYTE PROLIFERATION, APOPTOSIS, INFLAMMATION AND ECM DEPOSITION. HOWEVER, THE POSSIBILITY OF UNDERSTANDING THE MECHANISM BY WHICH DIFFERENT EPIGENETIC MODIFICATIONS OF MIRNA OR PRE-MIRNA SEQUENCES DRIVE THE AGGRESSIVENESS OF OA COULD BE THE NEW FOCUS OF FUTURE INVESTIGATIONS. 2023 8 2404 38 EPIGENETIC RESEARCH IN MULTIPLE SCLEROSIS: PROGRESS, CHALLENGES, AND OPPORTUNITIES. MULTIPLE SCLEROSIS (MS) IS A CHRONIC INFLAMMATORY AND DEMYELINATING DISEASE OF THE CENTRAL NERVOUS SYSTEM. MS LIKELY RESULTS FROM A COMPLEX INTERPLAY BETWEEN PREDISPOSING CAUSAL GENE VARIANTS (THE STRONGEST INFLUENCE COMING FROM HLA CLASS II LOCUS) AND ENVIRONMENTAL RISK FACTORS SUCH AS SMOKING, INFECTIOUS MONONUCLEOSIS, AND LACK OF SUN EXPOSURE/VITAMIN D. HOWEVER, LITTLE IS KNOWN ABOUT THE MECHANISMS UNDERLYING MS DEVELOPMENT AND PROGRESSION. MOREOVER, THE CLINICAL HETEROGENEITY AND VARIABLE RESPONSE TO TREATMENT REPRESENT ADDITIONAL CHALLENGES TO A COMPREHENSIVE UNDERSTANDING AND EFFICIENT TREATMENT OF DISEASE. EPIGENETIC PROCESSES, SUCH AS DNA METHYLATION AND HISTONE POSTTRANSLATIONAL MODIFICATIONS, INTEGRATE INFLUENCES FROM THE GENES AND THE ENVIRONMENT TO REGULATE GENE EXPRESSION ACCORDINGLY. STUDYING EPIGENETIC MODIFICATIONS, WHICH ARE STABLE AND REVERSIBLE, MAY PROVIDE AN ALTERNATIVE APPROACH TO BETTER UNDERSTAND AND MANAGE DISEASE. WE HERE AIM TO REVIEW FINDINGS FROM EPIGENETIC STUDIES IN MS AND FURTHER DISCUSS THE CHALLENGES AND CLINICAL OPPORTUNITIES ARISING FROM EPIGENETIC RESEARCH, MANY OF WHICH APPLY TO OTHER DISEASES WITH SIMILAR COMPLEX ETIOLOGY. A GROWING BODY OF EVIDENCE SUPPORTS A ROLE OF EPIGENETIC PROCESSES IN THE MECHANISMS UNDERLYING IMMUNE PATHOGENESIS AND NERVOUS SYSTEM DYSFUNCTION IN MS. HOWEVER, DISPARITIES BETWEEN STUDIES SHED LIGHT ON THE NEED TO CONSIDER POSSIBLE CONFOUNDERS AND METHODOLOGICAL LIMITATIONS FOR A BETTER INTERPRETATION OF THE DATA. NEVERTHELESS, TRANSLATIONAL USE OF EPIGENETICS MIGHT OFFER NEW OPPORTUNITIES IN EPIGENETIC-BASED DIAGNOSTICS AND THERAPEUTIC TOOLS FOR A PERSONALIZED CARE OF MS PATIENTS. 2017 9 3404 31 HOW EPIGENETICS IMPACTS ON HUMAN DISEASES. EPIGENETICS IS A RAPIDLY GROWING FIELD OF BIOLOGY THAT STUDIES THE CHANGES IN GENE EXPRESSION THAT ARE NOT DUE TO ALTERATIONS IN THE DNA SEQUENCE BUT RATHER THE CHEMICAL MODIFICATIONS OF DNA AND ITS ASSOCIATED PROTEINS. EPIGENETIC MECHANISMS CAN PROFOUNDLY INFLUENCE GENE EXPRESSION, CELL DIFFERENTIATION, TISSUE DEVELOPMENT, AND DISEASE SUSCEPTIBILITY. UNDERSTANDING EPIGENETIC CHANGES IS ESSENTIAL TO ELUCIDATE THE MECHANISMS UNDERLYING THE INCREASINGLY RECOGNIZED ROLE OF ENVIRONMENTAL AND LIFESTYLE FACTORS IN HEALTH AND DISEASE AND THE INTERGENERATIONAL TRANSMISSION OF PHENOTYPES. RECENT STUDIES SUGGEST EPIGENETICS MAY BE CRITICAL IN VARIOUS DISEASES, FROM CARDIOVASCULAR DISEASE AND CANCER TO NEURODEVELOPMENTAL AND NEURODEGENERATIVE DISORDERS. EPIGENETIC MODIFICATIONS ARE POTENTIALLY REVERSIBLE AND COULD PROVIDE NEW THERAPEUTIC AVENUES FOR TREATING THESE DISEASES USING EPIGENETIC MODULATORS. MOREOVER, EPIGENETICS PROVIDE INSIGHT INTO DISEASE PATHOGENESIS AND BIOMARKERS FOR DISEASE DIAGNOSIS AND RISK STRATIFICATION. NEVERTHELESS, EPIGENETIC INTERVENTIONS HAVE THE POTENTIAL FOR UNINTENDED CONSEQUENCES AND MAY POTENTIALLY LEAD TO INCREASED RISKS OF UNEXPECTED OUTCOMES, SUCH AS ADVERSE DRUG REACTIONS, DEVELOPMENTAL ABNORMALITIES, AND CANCER. THEREFORE, RIGOROUS STUDIES ARE ESSENTIAL TO MINIMIZE THE RISKS ASSOCIATED WITH EPIGENETIC THERAPIES AND TO DEVELOP SAFE AND EFFECTIVE INTERVENTIONS FOR IMPROVING HUMAN HEALTH. THIS ARTICLE PROVIDES A SYNTHETIC AND HISTORICAL VIEW OF THE ORIGIN OF EPIGENETICS AND SOME OF THE MOST RELEVANT ACHIEVEMENTS. 2023 10 6288 37 THE POTENTIAL ROLE OF EPIGENETIC MODIFICATIONS ON DIFFERENT FACETS IN THE PERIODONTAL PATHOGENESIS. PERIODONTITIS IS A CHRONIC INFLAMMATORY DISEASE THAT AFFECTS THE SUPPORTING STRUCTURES OF TEETH. IN THE LITERATURE, THE ASSOCIATION BETWEEN THE PATHOGENICITY OF BACTERIA AND ENVIRONMENTAL FACTORS IN THIS REGARD HAVE BEEN EXTENSIVELY EXAMINED. IN THE PRESENT STUDY, WE WILL SHED LIGHT ON THE POTENTIAL ROLE THAT EPIGENETIC CHANGE CAN PLAY ON DIFFERENT FACETS OF ITS PROCESS, MORE PARTICULARLY THE MODIFICATIONS CONCERNING THE GENES INVOLVED IN INFLAMMATION, DEFENSE, AND IMMUNE SYSTEMS. SINCE THE 1960S, THE ROLE OF GENETIC VARIANTS IN THE ONSET AND SEVERITY OF PERIODONTAL DISEASE HAS BEEN WIDELY DEMONSTRATED. THESE MAKE SOME PEOPLE MORE SUSCEPTIBLE TO DEVELOPING IT THAN OTHERS. IT HAS BEEN DOCUMENTED THAT THE WIDE VARIATION IN ITS FREQUENCY FOR VARIOUS RACIAL AND ETHNIC POPULATIONS IS DUE PRIMARILY TO THE COMPLEX INTERPLAY AMONG GENETIC FACTORS WITH THOSE AFFECTING THE ENVIRONMENT AND THE DEMOGRAPHY. IN MOLECULAR BIOLOGY, EPIGENETIC MODIFICATIONS ARE DEFINED AS ANY CHANGE IN THE PROMOTER FOR THE CPG ISLANDS, IN THE STRUCTURE OF THE HISTONE PROTEIN, AS WELL AS POST-TRANSLATIONAL REGULATION BY MICRORNAS (MIRNAS), BEING KNOWN TO CONTRIBUTE TO THE ALTERATION IN GENE EXPRESSION FOR COMPLEX MULTIFACTORIAL DISEASES SUCH AS PERIODONTITIS. THE KEY ROLE OF EPIGENETIC MODIFICATION IS TO UNDERSTAND THE MECHANISM INVOLVED IN THE GENE-ENVIRONMENT INTERACTION, AND THE DEVELOPMENT OF PERIODONTITIS IS NOW THE SUBJECT OF MORE AND MORE STUDIES THAT ATTEMPT TO IDENTIFY WHICH FACTORS ARE STIMULATING IT, BUT ALSO AFFECT THE REDUCED RESPONSE TO THERAPY. 2023 11 2333 30 EPIGENETIC REGULATION OF INFLAMMATION: THE METABOLOMICS CONNECTION. EPIGENETIC FACTORS ARE CONSIDERED THE REGULATOR OF COMPLEX MACHINERY BEHIND INFLAMMATORY DISORDERS AND SIGNIFICANTLY CONTRIBUTED TO THE EXPRESSION OF INFLAMMATION-ASSOCIATED GENES. EPIGENETIC MODIFICATIONS MODULATE VARIATION IN THE EXPRESSION PATTERN OF TARGET GENES WITHOUT AFFECTING THE DNA SEQUENCE. THE CURRENT KNOWLEDGE OF EPIGENETIC RESEARCH FOCUSED ON THEIR ROLE IN THE PATHOGENESIS OF VARIOUS INFLAMMATORY DISEASES THAT CAUSES MORBIDITY AND MORTALITY WORLDWIDE. INFLAMMATORY DISEASES ARE CATEGORIZED AS ACUTE AND CHRONIC BASED ON THE DISEASE SEVERITY AND ARE REGULATED BY THE EXPRESSION PATTERN OF VARIOUS GENES. HENCE, UNDERSTANDING THE ROLE OF EPIGENETIC MODIFICATIONS DURING INFLAMMATION PROGRESSION WILL CONTRIBUTE TO THE DISEASE OUTCOMES AND THERAPEUTIC APPROACHES. THIS REVIEW ALSO FOCUSES ON THE METABOLOMICS APPROACH ASSOCIATED WITH THE STUDY OF INFLAMMATORY DISORDERS. INFLAMMATORY RESPONSES AND METABOLIC REGULATION ARE HIGHLY INTEGRATED AND VARIOUS ADVANCED TECHNIQUES ARE ADOPTED TO STUDY THE METABOLIC SIGNATURE MOLECULES. HERE WE DISCUSS SEVERAL METABOLOMICS APPROACHES USED TO LINK INFLAMMATORY DISORDERS AND EPIGENETIC CHANGES. WE PROPOSED THAT DECIPHERING THE MECHANISM BEHIND THE INFLAMMATION-METABOLISM LOOP MAY HAVE IMMENSE IMPORTANCE IN BIOMARKERS RESEARCH AND MAY ACT AS A PRINCIPAL COMPONENT IN DRUG DISCOVERY AS WELL AS THERAPEUTIC APPLICATIONS. 2022 12 2413 26 EPIGENETIC SIGNALING AND RNA REGULATION IN CARDIOVASCULAR DISEASES. RNA EPIGENETICS IS PERHAPS THE MOST RECENT FIELD OF INTEREST FOR TRANSLATIONAL EPIGENETICISTS. RNA MODIFICATIONS CREATE SUCH AN EXTENSIVE NETWORK OF EPIGENETICALLY DRIVEN COMBINATIONS WHOSE ROLE IN PHYSIOLOGY AND PATHOPHYSIOLOGY IS STILL FAR FROM BEING ELUCIDATED. NOT SURPRISINGLY, SOME OF THE PLAYERS DETERMINING CHANGES IN RNA STRUCTURE ARE IN COMMON WITH THOSE INVOLVED IN DNA AND CHROMATIN STRUCTURE REGULATION, WHILE OTHER MOLECULES SEEM VERY SPECIFIC TO RNA. IT IS ENVISAGED, THEN, THAT NEW SMALL MOLECULES, ACTING SELECTIVELY ON RNA EPIGENETIC CHANGES, WILL BE REPORTED SOON, OPENING NEW THERAPEUTIC INTERVENTIONS BASED ON THE CORRECTION OF THE RNA EPIGENETIC LANDSCAPE. IN THIS REVIEW, WE SHALL SUMMARIZE SOME ASPECTS OF RNA EPIGENETICS LIMITED TO THOSE IN WHICH THE POTENTIAL CLINICAL TRANSLATABILITY TO CARDIOVASCULAR DISEASE IS EMERGING. 2020 13 3028 35 GENETICS OF COMPLEX AIRWAY DISEASE. THE PAST 3 YEARS HAVE SEEN HIGHLY SIGNIFICANT GENETIC EFFECTS IDENTIFIED FOR A WIDE VARIETY OF COMMON COMPLEX DISEASES, INCLUDING THE AIRWAY DISORDERS OF ASTHMA AND CHRONIC OBSTRUCTIVE PULMONARY DISEASE. IT APPEARS THAT ONLY A PORTION OF THE GENETICALLY MEDIATED SUSCEPTIBILITY TO COMPLEX DISEASES HAS BEEN IDENTIFIED, AND THERE IS MUCH LEFT TO BE DISCOVERED. THIS REVIEW BRIEFLY DESCRIBES THE RESULTS OF THE GENOME-WIDE ASSOCIATION STUDIES OF ASTHMA AND GIVES AN OVERVIEW OF THE PARALLEL AND INCREASINGLY LARGE-SCALE STUDIES THAT ARE TAKING PLACE WITH CHRONIC OBSTRUCTIVE PULMONARY DISEASE. THE FUTURE IMPACT IS DISCUSSED OF TECHNOLOGICAL ADVANCES THAT ALLOW INCREASINGLY LARGE-SCALE GENE EXPRESSION STUDIES, NEXT-GENERATION SEQUENCING, AND GENOME-WIDE TESTING FOR EPIGENETIC EFFECTS. THE USE OF GENETIC TECHNOLOGY TO EXAMINE THE AIRWAY MICROBIOTA THAT INTERACT WITH THE MUCOSA IN HEALTH AND DISEASE IS DESCRIBED. 2011 14 396 38 AN UPDATE ON EPIGENETICS AND CHILDHOOD RESPIRATORY DISEASES. EPIGENETIC MECHANISMS, DEFINED AS CHANGES IN PHENOTYPE OR GENE EXPRESSION CAUSED BY MECHANISMS OTHER THAN CHANGES IN THE UNDERLYING DNA SEQUENCE, HAVE BEEN PROPOSED TO CONSTITUTE A LINK BETWEEN GENETIC AND ENVIRONMENTAL FACTORS THAT AFFECT COMPLEX DISEASES. RECENT STUDIES SHOW THAT DNA METHYLATION, ONE OF THE KEY EPIGENETIC MECHANISMS, IS ALTERED IN CHILDREN EXPOSED TO AIR POLLUTANTS AND ENVIRONMENTAL TOBACCO SMOKE EARLY IN LIFE. SEVERAL CANDIDATE GENE STUDIES ON EPIGENETICS HAVE BEEN PUBLISHED TO DATE, BUT IT IS ONLY RECENTLY THAT GLOBAL METHYLATION ANALYSES HAVE BEEN PERFORMED FOR RESPIRATORY DISORDERS SUCH AS ASTHMA AND CHRONIC OBSTRUCTIVE PULMONARY DISEASE. HOWEVER, LARGE-SCALE STUDIES WITH ADEQUATE POWER ARE YET TO BE PRESENTED IN CHILDREN, AND IMPLICATIONS FOR CLINICAL USE REMAIN TO BE EVALUATED. IN THIS REVIEW, WE SUMMARIZE THE RECENT ADVANCES IN EPIGENETICS AND RESPIRATORY DISORDERS IN CHILDREN, WITH A MAIN FOCUS ON METHODOLOGICAL CHALLENGES AND ANALYSES RELATED TO PHENOTYPE AND EXPOSURE USING GLOBAL METHYLATION APPROACHES. 2014 15 5256 49 PROGRESSES IN EPIGENETIC STUDIES OF ASTHMA FROM THE PERSPECTIVE OF HIGH-THROUGHPUT ANALYSIS TECHNOLOGIES: A NARRATIVE REVIEW. BACKGROUND AND OBJECTIVE: ASTHMA IS THE MOST COMMON CHRONIC RESPIRATORY DISEASE IN THE WORLD WITH AN ESTIMATED HERITABILITY BETWEEN 50% AND 60%, AND RECENT STUDIES HAVE SHOWN THAT EPIGENETIC MECHANISMS PLAY AN IMPORTANT ROLE IN ITS DEVELOPMENT. MANY CUTTING-EDGE EPIGENETIC RESEARCH TECHNIQUES HAVE BEEN APPLIED TO THE STUDY OF THE PATHOGENESIS OF ASTHMA, WHICH HAS PROMOTED THE DEVELOPMENT OF ASTHMA ETIOLOGY AND BROUGHT NEW POSSIBILITIES FOR TREATMENT. WE SUMMARIZED RECENT ADVANCES IN EPIGENETIC RESEARCH OF THE PATHOGENESIS OF ASTHMA, ESPECIALLY FROM THE PERSPECTIVE OF HIGH-THROUGHPUT ANALYSIS TECHNIQUES, TO FIND POTENTIAL EPIGENETIC BIOMARKERS AND POSSIBLE MOLECULAR TARGETS FOR THE FUTURE INTERVENTION AND TREATMENT OF THE DISEASE. METHODS: WE REVIEWED AND SUMMARIZED RECENT PROGRESS IN EPIGENOMIC STUDIES OF ASTHMA ON A "PRE-TRANSCRIPTIONAL LEVEL", INCLUDING DNA METHYLATION, HISTONE MODIFICATION, AND CHROMATIN REMODELING, AND ON A "POST-TRANSCRIPTIONAL LEVEL" WITH A FOCUS ON NON-CODING RNA, FROM THE PERSPECTIVE OF HIGH-THROUGHPUT ANALYSIS TECHNOLOGIES. KEY CONTENT AND FINDINGS: WE HAVE SUMMARIZED THE PROGRESS OF DIFFERENT KINDS OF RECENT EPIGENETIC STUDIES IN ASTHMA, INCLUDING DNA METHYLATION STUDIES [CANDIDATE GENES METHYLATION STUDIES AND EPIGENOME-WIDE ASSOCIATION STUDY (EWAS)], HISTONE MODIFICATION STUDIES (HISTONE ACETYLATION/DEACETYLATION STUDIES AND HISTONE METHYLATION STUDIES), NON-CODING RNA STUDIES [MICRORNAS (MIRNAS), LONG NON-CODING RNAS (LNCRNAS) AND CIRCULAR RNAS (CIRCRNAS)], TO HELP THE READERS TO GAIN A COMPREHENSIVE INSIGHT INTO THE EPIGENETIC RESEARCH FIELDS FOR ASTHMA. THE APPLICATION OF HIGH-THROUGHPUT ANALYSIS TECHNIQUES IN ASTHMA RESEARCH, INCLUDING EWAS (DNA METHYLATION CHIPS), CHROMATIN IMMUNOPRECIPITATION SEQUENCING (CHIP-SEQ), MICRORNA SEQUENCING, WHOLE TRANSCRIPTOME SEQUENCING, CO-EXPRESSION NETWORK AND COMPETING ENDOGENOUS RNA (CERNA) ANALYSES, WERE INTRODUCED ACCOMPANY WITH THE MAIN FINDINGS. AND THE POTENTIAL EPIGENETIC BIOMARKERS AND POSSIBLE MOLECULAR TARGETS IDENTIFIED VIA HIGH-THROUGHPUT ANALYSES WERE ALSO DISCUSSED. CONCLUSIONS: EPIGENETIC RESEARCH HAS BECOME A HOTSPOT IN RESEARCH ON THE PATHOGENESIS OF ASTHMA. THE COMBINATION OF HIGH-THROUGHPUT EPIGENETIC ANALYSIS TECHNOLOGIES AND TRADITIONAL BIOLOGICAL FUNCTION AND CLINICAL STUDIES WILL BRING NEW BREAKTHROUGH IN THE PATHOGENESIS STUDY OF ASTHMA, WHICH WILL IMPROVE THE GENETIC INTERPRETATION OF THE DISEASE AND BRING MORE POSSIBILITIES FOR THE DEVELOPMENT OF PRECISION MEDICINE TO TREAT IT. 2022 16 2282 35 EPIGENETIC REGULATION IN EXPOSOME-INDUCED TUMORIGENESIS: EMERGING ROLES OF NCRNAS. ENVIRONMENTAL FACTORS, INCLUDING POLLUTANTS AND LIFESTYLE, CONSTITUTE A SIGNIFICANT ROLE IN SEVERE, CHRONIC PATHOLOGIES WITH AN ESSENTIAL SOCIETAL, ECONOMIC BURDEN. THE MEASUREMENT OF ALL ENVIRONMENTAL EXPOSURES AND ASSESSING THEIR CORRELATION WITH EFFECTS ON INDIVIDUAL HEALTH IS DEFINED AS THE EXPOSOME, WHICH INTERACTS WITH OUR UNIQUE CHARACTERISTICS SUCH AS GENETICS, PHYSIOLOGY, AND EPIGENETICS. EPIGENETICS INVESTIGATES MODIFICATIONS IN THE EXPRESSION OF GENES THAT DO NOT DEPEND ON THE UNDERLYING DNA SEQUENCE. SOME STUDIES HAVE CONFIRMED THAT ENVIRONMENTAL FACTORS MAY PROMOTE DISEASE IN INDIVIDUALS OR SUBSEQUENT PROGENY THROUGH EPIGENETIC ALTERATIONS. VARIATIONS IN THE EPIGENETIC MACHINERY CAUSE A SPECTRUM OF DIFFERENT DISORDERS SINCE THESE MECHANISMS ARE MORE SENSITIVE TO THE ENVIRONMENT THAN THE GENOME, DUE TO THE INHERENT REVERSIBLE NATURE OF THE EPIGENETIC LANDSCAPE. SEVERAL EPIGENETIC MECHANISMS, INCLUDING MODIFICATIONS IN DNA (E.G., METHYLATION), HISTONES, AND NONCODING RNAS CAN CHANGE GENOME EXPRESSION UNDER THE EXOGENOUS INFLUENCE. NOTABLY, THE ROLE OF LONG NONCODING RNAS IN EPIGENETIC PROCESSES HAS NOT BEEN WELL EXPLORED IN THE CONTEXT OF EXPOSOME-INDUCED TUMORIGENESIS. IN THE PRESENT REVIEW, OUR SCOPE IS TO PROVIDE RELEVANT EVIDENCE INDICATING THAT EPIGENETIC ALTERATIONS MEDIATE THOSE DETRIMENTAL EFFECTS CAUSED BY EXPOSURE TO ENVIRONMENTAL TOXICANTS, FOCUSING MAINLY ON A MULTI-STEP REGULATION BY DIVERSE NONCODING RNAS SUBTYPES. 2022 17 1240 33 CURRENT ADVANCES OF EPIGENETICS IN PERIODONTOLOGY FROM ENCODE PROJECT: A REVIEW AND FUTURE PERSPECTIVES. BACKGROUND: THE ENCYCLOPEDIA OF DNA ELEMENTS (ENCODE) PROJECT HAS ADVANCED OUR KNOWLEDGE OF THE FUNCTIONAL ELEMENTS IN THE GENOME AND EPIGENOME. THE AIM OF THIS ARTICLE WAS TO PROVIDE THE COMPREHENSION ABOUT CURRENT RESEARCH TRENDS FROM ENCODE PROJECT AND ESTABLISH THE LINK BETWEEN EPIGENETICS AND PERIODONTAL DISEASES BASED ON EPIGENOME STUDIES AND SEEK THE FUTURE DIRECTION. MAIN BODY: GLOBAL EPIGENOME RESEARCH PROJECTS HAVE EMPHASIZED THE IMPORTANCE OF EPIGENETIC RESEARCH FOR UNDERSTANDING HUMAN HEALTH AND DISEASE, AND CURRENT INTERNATIONAL CONSORTIA SHOW AN IMPROVED INTEREST IN THE IMPORTANCE OF ORAL HEALTH WITH SYSTEMIC HEALTH. THE EPIGENETIC STUDIES IN DENTAL FIELD HAVE BEEN MAINLY CONDUCTED IN PERIODONTOLOGY AND HAVE FOCUSED ON DNA METHYLATION ANALYSIS. ADVANCES IN SEQUENCING TECHNOLOGY HAVE BROADENED THE TARGET FOR EPIGENETIC STUDIES FROM SPECIFIC GENES TO GENOME-WIDE ANALYSES. CONCLUSIONS: IN LINE WITH GLOBAL RESEARCH TRENDS, FURTHER EXTENDED AND ADVANCED EPIGENETIC STUDIES WOULD PROVIDE CRUCIAL INFORMATION FOR THE REALIZATION OF COMPREHENSIVE DENTAL MEDICINE AND EXPAND THE SCOPE OF ONGOING LARGE-SCALE RESEARCH PROJECTS. 2021 18 6809 29 [EPIGENETICS IN INFLAMMATORY SYSTEMIC DISEASES]. IN ADDITION TO ANALYSIS OF THE GENETIC CODE, IN RECENT YEARS MORE AND MORE STUDIES HAVE CONCENTRATED ON CHANGES IN THE EPIGENETIC CODE. EPIGENETIC MECHANISMS DETERMINE WHICH GENES IN A CELL ARE TRANSCRIBED AND THUS FORM THE PHENOTYPE OF A CELL. THE EPIGENETIC CODE CAN BE CHANGED BY ENVIRONMENTAL INFLUENCES, WHICH ALLOWS CELLS TO ADAPT TO LONGSTANDING CHANGES IN THE ENVIRONMENT. THEREFORE, IT IS FEASIBLE TO ASSUME THAT EPIGENETIC CHANGES ARE THE MOLECULAR BASIS FOR LONG-TERM EFFECTS OF THE ENVIRONMENT ON DISEASE DEVELOPMENT. IN PARTICULAR IN TUMORS AND CHRONIC INFLAMMATORY DISEASES EPIGENETIC CHANGES WERE FOUND TO CORRELATE WITH DISEASE SEVERITY AND PROGRESSION. KNOWLEDGE ABOUT THESE EPIGENETIC CHANGES MIGHT HELP THAT EPIGENETIC MODIFICATIONS CAN BE USED IN THE FUTURE AS BIOMARKERS, PROGNOSTIC FACTORS AND THERAPEUTIC TARGETS. 2014 19 738 27 CANCER SUSCEPTIBILITY: EPIGENETIC MANIFESTATION OF ENVIRONMENTAL EXPOSURES. CANCER IS A DISEASE THAT RESULTS FROM BOTH GENETIC AND EPIGENETIC CHANGES. DISCORDANT PHENOTYPES AND VARYING INCIDENCES OF COMPLEX DISEASES SUCH AS CANCER IN MONOZYGOTIC TWINS AS WELL AS GENETICALLY IDENTICAL LABORATORY ANIMALS HAVE LONG BEEN ATTRIBUTED TO DIFFERENCES IN ENVIRONMENTAL EXPOSURES. ACCUMULATING EVIDENCE INDICATES, HOWEVER, THAT DISPARITIES IN GENE EXPRESSION RESULTING FROM VARIABLE MODIFICATIONS IN DNA METHYLATION AND CHROMATIN STRUCTURE IN RESPONSE TO THE ENVIRONMENT ALSO PLAY A ROLE IN DIFFERENTIAL SUSCEPTIBILITY TO DISEASE. DESPITE A GROWING CONSENSUS ON THE IMPORTANCE OF EPIGENETICS IN THE ETIOLOGY OF CHRONIC HUMAN DISEASES, THE GENES MOST PRONE TO EPIGENETIC DYSREGULATION ARE INCOMPLETELY DEFINED. MOREOVER, NEITHER THE ENVIRONMENTAL AGENTS MOST STRONGLY AFFECTING THE EPIGENOME NOR THE CRITICAL WINDOWS OF VULNERABILITY TO ENVIRONMENTALLY INDUCED EPIGENETIC ALTERATIONS ARE ADEQUATELY CHARACTERIZED. THESE MAJOR DEFICITS IN KNOWLEDGE MARKEDLY IMPAIR OUR ABILITY TO UNDERSTAND FULLY THE ETIOLOGY OF CANCER AND THE IMPORTANCE OF THE EPIGENOME IN DIAGNOSING AND PREVENTING THIS DEVASTATING DISEASE. 2007 20 4325 36 MICRORNAS IN THE EVALUATION AND POTENTIAL TREATMENT OF LIVER DISEASES. ACUTE AND CHRONIC LIVER DISEASE CONTINUE TO RESULT IN SIGNIFICANT MORBIDITY AND MORTALITY OF PATIENTS, ALONG WITH INCREASING BURDEN ON THEIR FAMILIES, SOCIETY AND THE HEALTH CARE SYSTEM. THIS IN PART IS DUE TO INCREASED INCIDENCE OF LIVER DISEASE ASSOCIATED FACTORS SUCH AS METABOLIC SYNDROME; IMPROVED SURVIVAL OF PATIENTS WITH CHRONIC PREDISPOSING CONDITIONS SUCH AS HIV; AS WELL AS ADVANCES IN THE FIELD OF TRANSPLANTATION AND ASSOCIATED CARE LEADING TO IMPROVED SURVIVAL. THE FACT THAT ONE DISEASE CAN RESULT IN DIFFERENT MANIFESTATIONS AND OUTCOMES HIGHLIGHTS THE NEED FOR IMPROVED UNDERSTANDING OF NOT JUST GENETIC PHENOMENON PREDISPOSING TO A CONDITION, BUT ADDITIONALLY THE ROLE OF EPIGENETIC AND ENVIRONMENTAL FACTORS LEADING TO THE PHENOTYPE OF THE DISEASE. IT IS NOT SURPRISING THAT PROVIDERS CONTINUE TO FACE DAILY CHALLENGES PERTAINING TO DIAGNOSTIC ACCURACY, PROGNOSTICATION OF DISEASE SEVERITY, PROGRESSION, AND RESPONSE TO THERAPIES. A NUMBER OF THESE CHALLENGES CAN BE ADDRESSED BY INCORPORATING A PERSONALIZED APPROACH OF MANAGEMENT TO THE CURRENT PARADIGM OF CARE. RECENT ADVANCES IN THE FIELDS OF MOLECULAR BIOLOGY AND GENETICS HAVE PAVED THE WAY TO MORE ACCURATE, INDIVIDUALIZED AND PRECISE APPROACH TO CARING FOR LIVER DISEASE. THE STUDY OF MICRORNAS AND THEIR ROLE IN BOTH HEALTHY AND DISEASED LIVERS IS ONE EXAMPLE OF SUCH ADVANCES. AS THESE SMALL, NON-CODING RNAS WORK ON FINE-TUNING OF CELLULAR ACTIVITIES AND ORGAN FUNCTION IN A DYNAMIC AND PRECISE FASHION, THEY PROVIDE US A GOLDEN OPPORTUNITY TO ADVANCE THE FIELD OF HEPATOLOGY. THE STUDY OF MICRORNAS IN LIVER DISEASE PROMISES TREMENDOUS IMPROVEMENT IN HEPATOLOGY AND IS LIKELY TO LAY THE FOUNDATION TOWARDS A PERSONALIZED APPROACH IN LIVER DISEASE. 2016