1 6289 131 THE POTENTIAL ROLE OF GENETICS, ENVIRONMENTAL FACTORS, AND GUT DYSBIOSIS IN THE ABERRANT NON-CODING RNA EXPRESSION TO MEDIATE INFLAMMATION AND OSTEOCLASTOGENIC/OSTEOGENIC DIFFERENTIATION IN ANKYLOSING SPONDYLITIS. ANKYLOSING SPONDYLITIS (AS) OR RADIOGRAPHIC AXIAL SPONDYLOARTHRITIS IS A CHRONIC IMMUNE-MEDIATED RHEUMATIC DISORDER CHARACTERIZED BY THE INFLAMMATION IN THE AXIAL SKELETON, PERIPHERAL JOINTS, AND SOFT TISSUES (ENTHESIS, FASCIA, AND LIGAMENT). IN ADDITION, THE EXTRA-SKELETAL COMPLICATIONS INCLUDING ANTERIOR UVEITIS, INTERSTITIAL LUNG DISEASES AND AORTITIS ARE FOUND. THE PATHOGENESIS OF AS IMPLICATES AN INTRICATE INTERACTION AMONG HLA (HLA-B27) AND NON-HLA LOCI [ENDOPLASMIC RETICULUM AMINOPEPTIDASE 1 (ERAP1), AND INTERLEUKIN-23 RECEPTOR (IL23R), GUT DYSBIOSIS, IMMUNE PLASTICITY, AND NUMEROUS ENVIRONMENTAL FACTORS (INFECTIONS, HEAVY METALS, STRESS, CIGARETTE SMOKING, ETC.) THE LATTER MULTIPLE NON-GENETIC FACTORS MAY EXERT A POWERFUL STRESS ON EPIGENETIC REGULATIONS. THESE EPIGENETIC REGULATIONS OF GENE EXPRESSION CONTAIN DNA METHYLATION/DEMETHYLATION, HISTONE MODIFICATIONS AND ABERRANT NON-CODING RNAS (NCRNAS) EXPRESSION, LEADING TO INFLAMMATION AND IMMUNE DYSFUNCTIONS. IN THE PRESENT REVIEW, WE SHALL DISCUSS THESE CONTRIBUTORY FACTORS THAT ARE INVOLVED IN AS PATHOGENESIS, ESPECIALLY THE ABERRANT NCRNA EXPRESSION AND ITS EFFECTS ON THE PROINFLAMMATORY CYTOKINE PRODUCTIONS (TNF-ALPHA, IL-17 AND IL-23), T CELL SKEWING TO TH1/TH17, AND OSTEOCLASTOGENIC/OSTEOGENIC DIFFERENTIATION. FINALLY, SOME POTENTIAL INVESTIGATORY APPROACHES ARE RAISED FOR SOLVING THE PUZZLES IN AS PATHOGENESIS. 2021 2 3173 33 GUT MICROBIOTA-MICRORNA INTERACTIONS IN ANKYLOSING SPONDYLITIS. ANKYLOSING SPONDYLITIS (AS) IS A CHRONIC AUTOIMMUNE INFLAMMATORY DISABILITY THAT IS PART OF THE RHEUMATIC DISEASE GROUP OF SPONDYLOARTHROPATHIES. AS COMMONLY INFLUENCES THE JOINTS OF THE AXIAL SKELETON. THE CONTRIBUTIONS TO AS PATHOGENESIS OF GENETIC SUSCEPTIBILITY (PARTICULARLY HLA-B27 AND ERAP-1) AND EPIGENETIC MODIFICATIONS, LIKE NON-CODING RNAS, AS WELL AS ENVIRONMENTAL FACTORS, HAVE BEEN INVESTIGATED OVER THE LAST FEW YEARS. BUT THE FUNDAMENTAL ETIOLOGY OF AS REMAINS ELUSIVE TO DATE. THE EVIDENCE SUMMARIZED HERE INDICATES THAT IN THE IMMUNOPATHOGENESIS OF AS, MICRORNAS AND THE GUT MICROBIOME PERFORM CRITICAL FUNCTIONS. WE DISCUSS SIGNIFICANT ADVANCES IN THE IMMUNOLOGICAL MECHANISMS UNDERLYING AS AND ADDRESS POTENTIAL CROSS-TALK BETWEEN THE GUT MICROBIOME AND HOST MICRORNAS. THIS CRITICAL INTERACTION IMPLICATES A CO-EVOLUTIONARY SYMBIOTIC LINK BETWEEN HOST IMMUNITY AND THE GUT MICROBIOME. 2021 3 4676 36 NEW INSIGHTS TOWARD THE PATHOGENESIS OF ANKYLOSING SPONDYLITIS; GENETIC VARIATIONS AND EPIGENETIC MODIFICATIONS. ANKYLOSING SPONDYLITIS (AS) IS A CHRONIC INFLAMMATORY AUTOIMMUNE DISEASE, CHARACTERIZED BY TYPICALLY AN AXIAL ARTHRITIS. AS IS THE PROTOTYPE OF A GROUP OF DISORDERS CALLED SPONDYLOARTHROPATHIES, WHICH IS BELIEVED TO HAVE COMMON CLINICAL MANIFESTATIONS AND GENETIC PREDISPOSITION. TO DATE, THE EXACT ETIOLOGY OF AS REMAINS UNCLEAR. OVER THE PAST FEW YEARS, HOWEVER, THE ROLE OF GENETIC SUSCEPTIBILITY AND EPIGENETIC MODIFICATIONS CAUSED THROUGH ENVIRONMENTAL FACTORS HAVE BEEN EXTENSIVELY SURVEYED WITH RESPECT TO THE PATHOGENESIS OF AS, RESULTED IN IMPORTANT ADVANCES. THIS REVIEW ARTICLE FOCUSES ON THE RECENT ADVANCES IN THE FIELD OF AS RESEARCH, INCLUDING HLA AND NON-HLA SUSCEPTIBILITY GENES IDENTIFIED IN GENOME-WIDE ASSOCIATION STUDIES (GWAS), AND ABERRANT EPIGENETIC MODIFICATIONS OF GENE LOCI ASSOCIATED WITH AS. HLA GENES MOST SIGNIFICANTLY LINKED WITH AS SUSCEPTIBILITY INCLUDE HLA-B27 AND ITS SUBTYPES. NUMEROUS NON-HLA GENES SUCH AS THOSE IN UBIQUITINATION, AMINOPEPTIDASES AND MHC CLASS I PRESENTATION MOLECULES LIKE ERAP-1 WERE ALSO REPORTED. MOREOVER, EPIGENETIC MODIFICATIONS OCCURRED IN AS HAS BEEN SUMMARIZED. TAKEN TOGETHER, THE FINDINGS PRESENTED IN THIS REVIEW ATTEMPT TO EXPLAIN THE CIRCUMSTANCE BY WHICH BOTH GENETIC VARIATIONS AND EPIGENETIC MODIFICATIONS ARE INVOLVED IN TRIGGERING AND DEVELOPMENT OF AS. NONETHELESS, SEVERAL UNANSWERED DARK SIDES CONTINUE TO CLOG OUR EXHAUSTIVE UNDERSTANDING OF AS. FUTURE RESEARCHES IN THE FIELD OF EPIGENETICS SHOULD BE CARRIED OUT TO EXTEND OUR VISION OF AS ETIOPATHOGENESIS. 2017 4 555 38 AXIAL SPONDYLOARTHRITIS: RESHAPE THE FUTURE-FROM THE "2022 GISEA INTERNATIONAL SYMPOSIUM". THE TERM "AXIAL SPONDYLOARTHRITIS" (AXSPA) REFERS TO A GROUP OF CHRONIC RHEUMATIC DISEASES THAT PREDOMINANTLY INVOLVE THE AXIAL SKELETON AND CONSIST OF ANKYLOSING SPONDYLITIS, REACTIVE ARTHRITIS, ARTHRITIS/SPONDYLITIS ASSOCIATED WITH PSORIASIS (PSA) AND ARTHRITIS/SPONDYLITIS ASSOCIATED WITH INFLAMMATORY BOWEL DISEASES (IBD). MOREOVER, PAIN IS AN IMPORTANT AND COMMON SYMPTOM OF AXSPA. IT MAY PROGRESS TO CHRONIC PAIN, A MORE COMPLICATED BIO-PSYCHOSOCIAL PHENOMENA, LEADING TO A SIGNIFICANT WORSENING OF QUALITY OF LIFE. THE DEVELOPMENT OF THE AXSPA INFLAMMATORY PROCESS IS GROUNDED IN THE COMPLEX INTERACTION BETWEEN GENETIC (SUCH AS HLA B27), EPIGENETIC, AND ENVIRONMENTAL FACTORS ASSOCIATED WITH A DYSREGULATED IMMUNE RESPONSE. CONSIDERING THE PIVOTAL CONTRIBUTION OF IL-23 AND IL-17 IN AXSPA INFLAMMATION, THE INHIBITION OF THESE CYTOKINES HAS BEEN EVALUATED AS A POTENTIAL THERAPEUTIC STRATEGY. WITH THIS CONTEXT, HERE WE DISCUSS THE MAIN PATHOGENETIC MECHANISMS, THERAPEUTIC APPROACHES AND THE ROLE OF PAIN IN AXSPA FROM THE 2022 INTERNATIONAL GISEA/OEG SYMPOSIUM. 2022 5 2989 38 GENETIC FACTORS INVOLVED IN THE CO?OCCURRENCE OF ENDOMETRIOSIS WITH ANKYLOSING SPONDYLITIS (REVIEW). PREVIOUS RESEARCH HAS REVEALED AN ASSOCIATION BETWEEN ENDOMETRIOSIS AND VARIOUS AUTOIMMUNE DISEASES, WHILE RECENT DATA SUGGEST, FOR THE FIRST TIME, AN ASSOCIATION BETWEEN ENDOMETRIOSIS AND THE RISK OF DEVELOPING ANKYLOSING SPONDYLITIS (AS). AS, THE PROTOTYPE OF SPONDYLOARTHRITIDES DISEASES, IS A SYSTEMIC, CHRONIC, IMMUNE?MEDIATED INFLAMMATORY ARTHRITIS, WHICH PRIMARILY AFFECTS THE SPINE AND SACROILIAC JOINTS, AS WELL AS THE AXIAL SKELETON WITH OR WITHOUT EXTRASPINAL MANIFESTATIONS. AS IS OF POLYGENIC INHERITANCE AND NUMEROUS IMMUNOLOGICALLY RELEVANT GENES CONTRIBUTE TO ITS DEVELOPMENT. ENDOMETRIOSIS IS AN ENIGMATIC, RELATIVELY COMMON, BENIGN, ESTROGEN?DEPENDENT, HETEROGENEOUS GYNECOLOGICAL DISEASE, INFLUENCED BY MULTIPLE GENETIC, EPIGENETIC AND ENVIRONMENTAL FACTORS. IT IS CHARACTERIZED BY THE GROWTH OF ENDOMETRIAL TISSUE OCCURRING IN SITES OTHER THAN THE UTERINE CAVITY, MOST COMMONLY IN THE PELVIC CAVITY, INCLUDING THE OVARIES AND THE UTEROSACRAL LIGAMENTS, AFFECTING UP TO 10% OF THE FEMALE POPULATION OF CHILDBEARING AGE, CAUSING PAIN AND INFERTILITY. THE PRESENT REVIEW DISCUSSES WHETHER A PARTIALLY SHARED GENETIC BACKGROUND MAY EXPLAIN THE CO?OCCURRENCE OF THESE DISORDERS, AS WELL AS POTENTIAL SIMILARITIES REGARDING THE UNDERLYING PATHOGENETIC MECHANISMS AND SPECIFIC MOLECULAR AND CELLULAR PATHWAYS. 2023 6 4319 29 MICRORNAS IN AXIAL SPONDYLARTHRITIS: AN OVERVIEW OF THE RECENT PROGRESSES IN THE FIELD WITH A FOCUS ON ANKYLOSING SPONDYLITIS AND PSORIATIC ARTHRITIS. PURPOSE OF REVIEW: TO HIGHLIGHT THE RECENT DISCOVERIES AND LINES OF EVIDENCE ON THE ROLE OF MICRORNAS IN ANKYLOSING SPONDYLITIS (AS) AND PSORIATIC ARTHRITIS (PSA), FOCUSING ON THEIR EXPRESSION PROFILING AND MECHANISMS OF ACTION. RECENT FINDINGS: AS AND PSA ARE CHRONIC INFLAMMATORY MUSCULOSKELETAL DISEASES WITH AXIAL MANIFESTATIONS AND REPRESENT AN EXCELLENT MODEL FOR STUDYING MICRORNAS CONTRIBUTION TO THE DISEASE PATHOGENESIS, PARTICULARLY THROUGH IMMUNOMODULATION, INFLAMMATION, AND BONE REMODELLING, OR THEIR VALUE AS CANDIDATE DIAGNOSTIC AND PROGNOSTIC BIOMARKERS. MICRORNAS ARE SINGLE-STRANDED NUCLEOTIDES ABLE TO REGULATE GENE EXPRESSION. THEY ARE A KEY COMPONENT OF THE EPIGENETIC MACHINERY, INVOLVED IN PHYSIOLOGICAL AND PATHOLOGICAL PROCESSES. THE CONTRIBUTION OF MICRORNAS IN AS AND PSA (SUCH AS MIR-29A IN REGULATING BONE METABOLISM) IS HIGHLIGHTED BY SEVERAL WORKS IN THE FIELD BUT THEIR UTILITY AS POSSIBLE MARKERS MUST BE STILL CONFIRMED, PARTICULARLY IN LARGER PATIENTS' COHORTS. 2021 7 2569 32 EPIGENETICS OF ANKYLOSING SPONDYLITIS: RECENT DEVELOPMENTS. ANKYLOSING SPONDYLITIS (AS) IS A CHRONIC INFLAMMATORY AUTOIMMUNE DISEASE WHICH MAINLY AFFECTS THE SPINE, SACROILIAC JOINT AND PERIPHERAL JOINTS. TO DATE, THE EXACT CAUSES AND PATHOGENESIS OF AS STILL REMAIN UNKNOWN. IT IS CONSIDERED THAT THE PATHOGENESIS OF AS IS ASSOCIATED WITH GENETIC, INFECTION, ENVIRONMENT, IMMUNITY AND OTHER FACTORS. AMONG THEM, THE ROLE OF GENETIC FACTORS IN THE PATHOGENESIS OF AS HAS BEEN STUDIED MOST DEEPLY. HOWEVER, OVER THE PAST FEW YEARS, THE FUNCTION OF ENVIRONMENTAL PREDISPOSITION AND EPIGENETIC MODIFICATION IN THE PATHOGENESIS OF AS HAS RECEIVED EXTENSIVE ATTENTION. THIS PAPER SUMMARIZES THE RECENT PROGRESS IN THE EPIGENETICS OF AS, INCLUDING ABNORMAL EPIGENETIC MODIFICATIONS AT AS-ASSOCIATED GENOMIC LOCI, SUCH AS DNA METHYLATION, HISTONE MODIFICATION, MICRORNA, AND SO ON. IN SUMMARY, THE FINDINGS OF THIS REVIEW ATTEMPT TO EXPLAIN THE ROLE OF EPIGENETIC MODIFICATION IN THE OCCURRENCE AND DEVELOPMENT OF AS. NEVERTHELESS, THERE ARE STILL UNKNOWN AND COMPLICATED ASPECTS WORTH EXPLORING TO DEEPEN OUR UNDERSTANDING OF THE PATHOGENESIS OF AS. 2021 8 3057 31 GENOME-WIDE DNA METHYLATION ANALYSIS IN ANKYLOSING SPONDYLITIS IDENTIFIES HLA-B*27 DEPENDENT AND INDEPENDENT DNA METHYLATION CHANGES IN WHOLE BLOOD. BACKGROUND AND OBJECTIVE: ANKYLOSING SPONDYLITIS IS A CHRONIC INFLAMMATORY DISEASE CHARACTERIZED BY INFLAMMATION OF THE SACROILIAC JOINTS AND THE SPINE THAT CAN LEAD TO SIGNIFICANT PAIN, IMMOBILITY, AND DISABILITY. THE ETIOLOGY AND PATHOGENESIS OF ANKYLOSING SPONDYLITIS ARE INCOMPLETELY UNDERSTOOD, THOUGH MOST PATIENTS CARRY THE HLA-B*27 ALLELE. THE OBJECTIVE OF THIS STUDY WAS TO EVALUATE DNA METHYLATION CHANGES IN ANKYLOSING SPONDYLITIS WITH THE GOAL OF REVEALING NOVEL MECHANISTIC INSIGHTS INTO THIS DISEASE. METHODS: GENOME-WIDE DNA METHYLATION ANALYSIS WAS PERFORMED IN WHOLE BLOOD DNA SAMPLES USING THE INFINIUM METHYLATIONEPIC ARRAY IN PATIENTS WITH ANKYLOSING SPONDYLITIS COMPARED TO AGE, SEX, AND RACE MATCHED PATIENTS WITH OSTEOARTHRITIS AS A NON-INFLAMMATORY DISEASE CONTROL. WE STUDIED 24 PATIENTS WITH ANKYLOSING SPONDYLITIS, INCLUDING 12 PATIENTS WHO CARRY HLA-B*27 AND 12 PATIENTS WHO ARE HLA-B*27 NEGATIVE. DNA METHYLATION ANALYSIS WAS PERFORMED WITH ADJUSTMENT FOR BLOOD CELL COMPOSITION IN EACH SAMPLE. RESULTS: WE IDENTIFIED A TOTAL OF 67 DIFFERENTIALLY METHYLATED SITES BETWEEN ANKYLOSING SPONDYLITIS PATIENTS AND OSTEOARTHRITIS CONTROLS. HYPERMETHYLATED GENES FOUND INCLUDED GTPASE-RELATED GENES, WHILE HYPOMETHYLATED GENES INCLUDED HCP5, WHICH ENCODES A LNCRNA WITHIN THE MHC REGION, PREVIOUSLY ASSOCIATED WITH GENETIC RISK FOR PSORIASIS AND TOXIC EPIDERMAL NECROLYSIS. CARRYING HLA-B*27 WAS ASSOCIATED WITH ROBUST HYPOMETHYLATION OF HCP5, TUBULIN FOLDING COFACTOR A (TBCA) AND PHOSPHOLIPASE D FAMILY MEMBER 6 (PLD6) IN ANKYLOSING SPONDYLITIS PATIENTS. HYPOMETHYLATION WITHIN HCP5 INVOLVES A CPG SITE THAT CONTAINS A SINGLE NUCLEOTIDE POLYMORPHISM IN LINKAGE DISEQUILIBRIUM WITH HLA-B*27 AND THAT CONTROLS DNA METHYLATION AT THIS LOCUS IN AN ALLELE-SPECIFIC MANNER. CONCLUSIONS: A GENOME-WIDE DNA METHYLATION ANALYSIS IN ANKYLOSING SPONDYLITIS IDENTIFIED DNA METHYLATION PATTERNS THAT COULD PROVIDE POTENTIAL NOVEL INSIGHTS INTO THIS DISEASE. OUR FINDINGS SUGGEST THAT HLA-B*27 MIGHT PLAY A ROLE IN ANKYLOSING SPONDYLITIS IN PART THROUGH INDUCING EPIGENETIC DYSREGULATION. 2019 9 6787 23 [CONTRIBUTION OF NON-HLA GENES TO JUVENILE IDIOPATHIC ARTHRITIS SUSCEPTIBILITY]. JUVENILE IDIOPATHIC ARTHRITIS (JAL4) IS THE MOST COMMON CHRONIC RHEUMATOLOGIC DISEASE IN CHILDREN. JIA IS A GROUP OF DISORDERS THAT SHARE THE CLINICAL MANIFESTATION OF CHRONIC JOINT INFLAMMATION. THE HUMAN LEUKOCYTE ANTIGEN REGION (HLA) SEEMS TO BE A MAJOR SUSCEPTIBILITY LOCUS FOR JIA THAT IS ESTIMATED TO ACCOUNT FOR 17% OF FAMILIAL SEGREGATION OF THE DISEASE. GENOME-WIDE ASSOCIATION STUDIES (GWAS), CASE-CONTROL STUDIES AND META-ANALYSES OF THE POST-GWAS ERA REVEALED OVER 20 NON-HLA LOCI CONFERRING SUSCEPTIBILITY TO JIA. AT LEAST A HALF OF THOSE ARE SHARED BETWEEN JIA AND RHEUMATOID ARTHRITIS, AN ADULT RHEUMATIC DISEASE, THEREBY SUGGESTING FOR SIMILARITY OF PATHOGENIC MECHANISMS OF BOTH DISEASES. NEW FINDINGS ALSO SUGGEST FOR A LIKELY ROLE OF EPIGENETIC ALTERATIONS IN THE PATHOGENESIS OF JIA THAT SHOULD BE INVESTIGATED IN THE FUTURE. 2014 10 3033 38 GENETICS, EPIGENETICS, AND GENDER IMPACT IN AXIAL-SPONDYLOARTHRITIS SUSCEPTIBILITY: AN UPDATE ON GENETIC POLYMORPHISMS AND THEIR SEX RELATED ASSOCIATIONS. SPONDYLOARTHRITIS (SPA) IS A GROUP OF CHRONIC INFLAMMATORY RHEUMATIC DISEASE THAT CAN BE DIVIDED INTO PREDOMINANTLY AXIAL OR PREDOMINANTLY PERIPHERAL INVOLVEMENT, WITH OR WITHOUT ASSOCIATED PSORIASIS, INFLAMMATORY BOWEL DISEASE OR PREVIOUS INFECTION. AXIAL SPA (AXSPA) ENCOMPASSES ANKYLOSING SPONDYLITIS (AS) WITH RADIOLOGICAL SACROILIITIS, AND A TYPE WITHOUT RADIOGRAPHIC SACROILIITIS, CALLED "NON-RADIOGRAPHIC AXIAL SPA" (NR-AXSPA). MALES AND FEMALES SHOW LARGE DIFFERENCES IN THEIR SUSCEPTIBILITY TO SPA, SUCH AS DISTINCTIONS IN CLINICAL PATTERNS, PHENOTYPES AND IN THERAPEUTICAL RESPONSE, PARTICULARLY TO TNF INHIBITORS (TNFI). SEVERAL STUDIES INDICATE THAT AS WOMEN HAVE DOUBLED RISK TO FAILURE TNFI COMPARED WITH MALES. THIS DIVERSITY IN DRUGS' EFFICACY AMONG WOMEN AND MEN MAY BE CAUSED BY DIFFERENCES IN THE BALANCE OF SEX HORMONES AND IN GENE-SPECIFIC EXPRESSION LIKELY TRIGGERED BY X-CHROMOSOME INSTABILITY AND GENE-SPECIFIC EPIGENETIC MODIFICATIONS. EVIDENCE REPORTED THAT POLYMORPHISMS IN MICRORNAS ON X- AND OTHER CHROMOSOMES, SUCH AS MIR-146A, MIR-155, MIR-125A-5P, MIR-151A-3P AND MIR-22-3P, MIR-199A-5P COULD BE INVOLVED IN THE DIFFERENT CLINICAL PRESENTATION OF SPA, AS WELL AS DISEASE ACTIVITY. IN ADDITION, ASSOCIATION WITH NON-RESPONSE TO TNFI TREATMENT AND PRESENCE OF IRAK3 AND CHUCK GENES IN SPA PATIENTS WAS RECENTLY DETECTED. FINALLY, POLYMORPHISMS IN GENES INVOLVED IN IL-23/IL-17 PATHWAY, SUCH AS IN DRUG PHARMACODYNAMICS AND PHARMACOKINETICS MAY HAVE A ROLE IN RESPONSE TO TNFI, IL17I, AND IL23I. A MAJOR UNDERSTANDING OF GENOMIC VARIABILITY COULD HELP IN THE DEVELOPMENT OF NEW THERAPEUTIC TARGETS OR IN TAKING ADVANTAGES OF DIFFERENT MECHANISMS OF ACTION OF BIOLOGICAL DRUGS. MOVING FROM THE MULTIFACTORIAL ETIOLOGY OF DISEASE, THE PRESENT REVIEW AIMS AT EVALUATING GENETIC AND EPIGENETIC FACTORS AND THEIR RELATIONSHIP WITH SEX AND BDMARDS RESPONSE, HELPING TO INVESTIGATE THE DIFFERENT EXPRESSION AMONG MALES AND FEMALES OF GENES ON X- AND OTHER CHROMOSOMES, AS WELL AS MI-RNA, TO HIGHLIGHT RELATIONSHIPS BETWEEN SEX AND OCCURRENCE OF SPECIFIC PHENOTYPES AND SYMPTOMS OF THE DISEASE. MOREOVER, THE ROLE OF THE EPIGENETIC MODIFICATION IN RELATION TO IMMUNE-REGULATORY MECHANISMS WILL BE EVALUATED. 2021 11 6152 29 THE FUNCTION OF NCRNAS IN RHEUMATIC DISEASES. RHEUMATIC DISEASES ARE A GROUP OF CHRONIC HETEROGENEOUS AUTOIMMUNE DISORDERS CHARACTERIZED BY ABNORMAL REGULATION OF THE INNATE AND ADAPTIVE IMMUNE SYSTEMS. DESPITE EXTENSIVE EFFORTS, THE FULL SPECTRUM OF MOLECULAR FACTORS THAT CONTRIBUTE TO THE PATHOGENESIS OF RHEUMATIC DISEASES REMAINS UNCLEAR. NCRNAS CAN GOVERN GENE EXPRESSION AT THE TRANSCRIPTIONAL AND POST-TRANSCRIPTIONAL LEVELS IN MULTIPLE DISEASES. RECENT STUDIES HAVE DEMONSTRATED AN IMPORTANT ROLE FOR NCRNAS, SUCH AS MIRNAS AND LNCRNAS, IN THE DEVELOPMENT OF IMMUNE CELLS AND RHEUMATIC DISEASES. HERE, WE FOCUS ON THE EPIGENETIC REGULATORY ROLES OF NCRNAS IN THE PATHOGENESIS OF RHEUMATIC DISEASES AND AS BIOMARKERS OF DISEASE STATE. 2019 12 2556 22 EPIGENETICS IN RHEUMATOID ARTHRITIS. EPIGENETICS IS A STEADILY GROWING RESEARCH AREA. IN MANY HUMAN DISEASES, ESPECIALLY IN CANCERS, BUT ALSO IN AUTOIMMUNE DISEASES, EPIGENETIC ABERRATIONS HAVE BEEN FOUND. RHEUMATOID ARTHRITIS IS AN AUTOIMMUNE DISEASE CHARACTERIZED BY CHRONIC INFLAMMATION AND DESTRUCTION OF SYNOVIAL JOINTS. EVEN THOUGH THE ETIOLOGY IS NOT YET FULLY UNDERSTOOD, RHEUMATOID ARTHRITIS IS GENERALLY CONSIDERED TO BE CAUSED BY A COMBINATION OF GENETIC PREDISPOSITION, DEREGULATED IMMUNOMODULATION, AND ENVIRONMENTAL INFLUENCES. TO GAIN A BETTER UNDERSTANDING OF THIS DISEASE, RESEARCHERS HAVE BECOME INTERESTED IN STUDYING EPIGENETIC CHANGES IN RHEUMATOID ARTHRITIS. HERE, WE WANT TO REVIEW THE CURRENT KNOWLEDGE ON EPIGENETICS IN RHEUMATOID ARTHRITIS. 2010 13 2979 23 GENETIC BACKGROUND OF JUVENILE IDIOPATHIC ARTHRITIS. JUVENILE IDIOPATHIC ARTHRITIS (JIA) IS THE MOST COMMON CHRONIC RHEUMATOLOGIC DISEASE IN CHILDREN. JIA IS A GROUP OF DISORDERS THAT SHARE THE CLINICAL MANIFESTATION OF CHRONIC JOINT INFLAMMATION. THE HUMAN LEUKOCYTE ANTIGEN REGION (HLA) SEEMS TO BE A MAJOR SUSCEPTIBILITY LOCUS FOR JIA THAT IS ESTIMATED TO ACCOUNT FOR 17% OF FAMILIAL SEGREGATION OF THE DISEASE. TO DATE, AROUND 20 NON-HLA LOCI CONFERRING SUSCEPTIBILITY TO JIA WERE FOUND. AT LEAST A HALF OF THOSE ARE SHARED BETWEEN JIA AND RHEUMATOID ARTHRITIS (RA), AN ADULT RHEUMATIC DISEASE, THEREBY SUGGESTING FOR SIMILARITY OF PATHOGENIC MECHANISMS OF BOTH DISEASES. NEW FINDINGS ALSO SUGGEST FOR A LIKELY ROLE OF EPIGENETIC ALTERATIONS IN THE PATHOGENESIS OF JIA THAT SHOULD BE INVESTIGATED IN THE FUTURE. 2014 14 1226 27 CRITICAL ROLE OF GUT MICROBIOTA AND EPIGENETIC FACTORS IN THE PATHOGENESIS OF BEHCET'S DISEASE. BEHCET'S DISEASE (BD) IS A CHRONIC REFRACTORY MULTISYSTEM AUTOINFLAMMATORY DISEASE, CHARACTERIZED BY TYPICAL CLINICAL FEATURES OF NON-SPECIFIC VASCULITIS, ORAL AND GENITAL ULCERS, UVEITIS, AS WELL AS SKIN LESIONS. THE EXACT ETIOPATHOGENESIS OF BD REMAINS UNKNOWN, EXISTING STUDIES HAVE INDICATED THAT GENETICS AND ENVIRONMENTAL FACTORS CONTRIBUTE TO THE INCREASED DEVELOPMENT OF BD. RECENTLY, SEVERAL STUDIES HAVE SHOWN THAT EXTERNAL ENVIRONMENTAL FACTORS CAN AFFECT THE PROCESS OF EPIGENETIC MODIFICATION, AND ABNORMALITIES OF EPIGENETIC FACTORS HAVE BEEN CONFIRMED TO BE INVOLVED IN THE OCCURRENCE OF BD. AT THE SAME TIME, ABNORMALITIES OF GUT MICROBIOTA (GM) IN THE BODY, HAVE ALSO BEEN CONFIRMED TO PARTICIPATE IN THE PATHOGENESIS OF BD BY REGULATING THE BALANCE OF TH17/TREGS. THIS ARTICLE REVIEWS THE PATHOGENESIS OF BD AND SUMMARIZES NUMEROUS CLINICAL STUDIES, FOCUSING ON THE MECHANISM OF GM AND EPIGENETIC FACTORS IMPACTING ON BD, AND PROVIDING NEW IDEAS FOR FURTHER ELUCIDATING THE PATHOGENESIS OF BD. 2021 15 5421 31 REGULATION OF INTERLEUKIN-23 EXPRESSION IN HEALTH AND DISEASE. INTERLEUKIN (IL)-23 PLAYS A CENTRAL ROLE IN THE ORCHESTRATION OF INFLAMMATORY RESPONSES. PRODUCED BY DENDRITIC CELLS AND MACROPHAGES, THIS CYTOKINE PROMOTES THE PROTECTION OF THE HOST AGAINST MUCOSAL PATHOGENS THROUGH THE INDUCTION OF IL-17 AND RELATED CYTOKINES BY LYMPHOID CELLS. PRECLINICAL DISEASE MODELS AND ASSOCIATION STUDIES IN HUMANS HAVE ALSO CLEARLY DEMONSTRATED THE IMPLICATION OF IL-23 SIGNALLING PATHWAY IN INFLAMMATORY DISEASES. INDEED, THIS CYTOKINE IS NOW CONSIDERED AS A MAJOR THERAPEUTIC TARGET IN IMMUNE-BASED PATHOLOGIES SUCH AS PSORIASIS, ANKYLOSING SPONDYLITIS OR CROHN'S DISEASE. FURTHERMORE, IN THE CONTEXT OF INFLAMMATION-RELATED CANCER, IL-23 IS THOUGHT TO CONTRIBUTE TO TUMORIGENESIS AND PROGRESSION TO METASTATIC DISEASE. HEREIN, WE REVIEW OUR CURRENT UNDERSTANDING OF IL-23 REGULATION AT THE TRANSCRIPTIONAL AND POST-TRANSCRIPTIONAL LEVELS. WE DISCUSS THE RELEVANCE OF THESE FINDINGS IN THE CONTEXT OF INFECTION, CHRONIC INFLAMMATION AND CANCER. 2016 16 1879 30 EMERGING ROLES OF NON-CODING RNAS IN PSORIASIS PATHOGENESIS. PSORIASIS IS A COMPLEX GENETIC SKIN DISORDER TYPICALLY MANIFESTED BY RED, SCALY, AND ITCHY PLAQUES MOST COMMONLY OVER THE SCALP, TRUNK, ELBOWS, AND KNEES. HISTOPATHOLOGICAL FEATURES INCLUDE THICKENING OF THE EPIDERMAL LAYER DUE TO HYPER-PROLIFERATION AND ABNORMAL DIFFERENTIATION OF EPIDERMAL KERATINOCYTES ALONG WITH INFILTRATION OF IMMUNE CELLS IN THE PSORIATIC SKIN. IT IS A CHRONIC INFLAMMATORY RELAPSING DISEASE, AND THERE IS CURRENTLY NO PERMANENT CURE FOR PSORIASIS. PROPER MEDICATIONS CAN REDUCE THE SEVERITY OF THE DISEASE AND IMPROVE THE QUALITY OF LIFE OF THE PATIENTS. WHILE THE GENETIC COMPONENTS OF PSORIASIS PATHOGENESIS ARE WELL EXPLORED, THE FULL UNDERSTANDING OF ITS EPIGENETIC COMPONENT REMAINS ELUSIVE. NON-CODING RNAS (NCRNAS) ARE DOCUMENTED TO REGULATE VARIOUS EPIGENETIC PROCESSES THAT LEAD TO THE PATHOGENESIS OF DIFFERENT DISEASES INCLUDING PSORIASIS. IN THIS REVIEW, WE HAVE DISCUSSED THE MOLECULAR INTERPLAY OF DIFFERENT NCRNAS IN PSORIASIS PATHOGENESIS. THE ROLES OF MICRORNAS (MIRNAS) IN PSORIASIS ARE PRETTY WELL STUDIED, WHEREAS THE ROLES OF LONG NONCODING RNAS (LNCRNAS) AND CIRCULAR RNAS (CIRCRNAS) ARE EMERGING. THIS REVIEW PROVIDES IDEAS COVERING SOME OF THE LATEST FINDINGS OF DIFFERENT MODES OF FUNCTIONS PLAYED BY THOSE DIFFERENT NCRNAS DOCUMENTED IN THE LITERATURE. AS AN EVER-EVOLVING TOPIC, SOME WORKS ARE STILL ONGOING AS WELL AS THERE ARE SEVERAL FIELDS THAT NEED RIGOROUS SCIENTIFIC VENTURES. WE HAVE PROPOSED THE AREAS WHICH CLAIM MORE EXPLORATIONS TO BETTER UNDERSTAND THE ROLES PLAYED BY THE NCRNAS IN PSORIASIS PATHOGENESIS. 2023 17 4318 33 MICRORNAS IN ANKYLOSING SPONDYLITIS: FUNCTION, POTENTIAL AND CHALLENGES. EPIGENETIC MECHANISMS SUCH AS DNA METHYLATION, HISTONE MODIFICATIONS AND NON-CODING RNA, ARE CONSIDERED THE ESSENTIAL CONNECTION BETWEEN A DISORDER'S ONSET AND THE ENVIRONMENT, ON A PERMISSIVE GENETIC BACKGROUND. AMONG AUTOIMMUNE AND INFLAMMATORY-MEDIATED DISORDERS, ANKYLOSING SPONDYLITIS (AS), A CHRONIC ARTHRITIS OF THE SPINE, IS A VERY GOOD EXAMPLE FOR THE WEIGHT OF EPIGENETICS' CONTRIBUTION. MICRORNAS (MIRNAS) ARE SINGLE-STRANDED NUCLEOTIDES WHICH REGULATE GENE EXPRESSION AND ARE INVOLVED IN PATHOLOGICAL AND PHYSIOLOGICAL PROCESSES. IN THIS MANUSCRIPT WE PROVIDE A CLARIFICATION ON THE ROLE OF MICRORNAS IN AS, WITH A FOCUS ON THE MECHANISMS OF PATHOGENESIS. IN SPECIFIC, WE HAVE EXAMINED THE CONTRIBUTION OF MIRNAS IN THE PROCESSES OF INFLAMMATION, NEW BONE FORMATION AND T-CELL FUNCTION, AND THE PATHWAYS (I.E. WNT, BMP, TGFBETA SIGNALLING ETC.) THEY REGULATE. THE UTILITY OF MIRNAS IN BETTER UNDERSTANDING AS PATHOGENESIS IS UNDISPUTED AND THEIR UTILITY AS THERAPEUTIC OPPORTUNITY IS STRONGLY INCREASING. 2020 18 4962 38 PATHOGENESIS OF PSORIATIC ARTHRITIS. PSORIATIC ARTHRITIS (PSA) IS A CHRONIC INFLAMMATORY ARTHROPATHY INVOLVING SYNOVIAL AND ENTHESEAL STRUCTURES, ASSOCIATED WITH PSORIASIS OR SIMILAR CONDITIONS. THE ETIOPATHOGENETIC MECHANISMS UNDERLYING PSA REMAIN UNCLARIFIED. THE MOST ACCREDITED HYPOTHESIS INVOLVES A COMPLEX INTERACTION AMONG GENETIC, ENVIRONMENTAL, AND IMMUNOLOGICAL FACTORS. ENVIRONMENTAL AGENTS, PARTICULARLY TRAUMA, MECHANICAL STRESS, AND SMOKE HAVE BEEN CITED AS POSSIBLE FACTORS IN TRIGGERING THE DISEASE IN GENETICALLY PREDISPOSED SUBJECTS. LIKE OTHER FORMS OF SPONDYLOARTHROPATHIES, PSA SHOWS SEVERAL GENETIC ASSOCIATIONS WITH THE MAJOR HISTOCOMPATIBILITY COMPLEX (MHC) CLASS I ALLELES LOCATED ON CHROMOSOME 6P21.3, PARTICULARLY THE HUMAN LEUKOCYTE ANTIGEN (HLA)-B27 IN AXIAL PHENOTYPES. RECENT STUDIES HAVE DEMONSTRATED THAT THE MOST COMMON EPIGENETIC MECHANISMS THAT REGULATE GENE EXPRESSION IN PSA ARE REPRESENTED BY DNA METHYLATION, PARENT OF ORIGIN EFFECT OR GENOMIC IMPRINTING, EXPRESSION OR ACTIVITY OF EPIGENETIC MODIFYING ENZYMES, AND RNA INTERFERENCE (RNAI) BY MICRORNAS (MIRNAS). THE MECHANISMS UNDERLYING PSA PATHOGENESIS ACTIVATE THE INNATE AND ADAPTIVE IMMUNE SYSTEM AND OVEREXPRESSION OF TNF ASSOCIATED WITH AMPLIFICATION OF THE IL-23/IL-17 AXIS. IN RECENT YEARS, MORE PSA SUSCEPTIBILITY GENES AND EPIGENETIC MECHANISMS HAVE BEEN IDENTIFIED. ADVANCES IN THE KNOWLEDGE OF INNATE AND ADAPTIVE IMMUNE MECHANISMS UNDERLYING PSA HAVE CONTRIBUTED TO A BETTER UNDERSTANDING OF THE HETEROGENEOUS CLINICAL EXPRESSION OF THE DISEASE AND, THUS, TO THERAPY STRATEGIES. THE COMPLEXITY OF THE PATHOGENETIC ASPECTS INVOLVING MULTIPLE CYTOKINES, CELL LINES, AND MOLECULES NEEDS TO BE FURTHER INVESTIGATED TO ADVANCE PERSONALIZED THERAPEUTIC STRATEGIES AND TO IMPROVE OUTCOMES OF PATIENTS AFFECTED BY PSA. 2019 19 4452 29 MOLECULAR MECHANISMS AND MANAGEMENT OF A CUTANEOUS INFLAMMATORY DISORDER: PSORIASIS. PSORIASIS IS A COMPLEX CHRONIC INFLAMMATORY CUTANEOUS DISORDER. TO DATE, ROBUST MOLECULAR MECHANISMS OF PSORIASIS HAVE BEEN REPORTED. AMONG DIVERSE ABERRANT IMMUNOPATHOGENETIC MECHANISMS, THE CURRENT MODEL EMPHASIZES THE ROLE OF TH1 AND THE IL-23/TH17 AXIS, SKIN-RESIDENT IMMUNE CELLS AND MAJOR SIGNAL TRANSDUCTION PATHWAYS INVOLVED IN PSORIASIS. THE MULTIPLE GENETIC RISK LOCI FOR PSORIASIS HAVE BEEN RAPIDLY REVEALED WITH THE ADVENT OF A NOVEL TECHNOLOGY. MOREOVER, IDENTIFYING EPIGENETIC MODIFICATIONS COULD BRIDGE THE GAP BETWEEN GENETIC AND ENVIRONMENTAL RISK FACTORS IN PSORIASIS. THIS REVIEW WILL PROVIDE A BETTER UNDERSTANDING OF THE PATHOGENESIS OF PSORIASIS BY UNRAVELING THE COMPLICATED INTERPLAY AMONG IMMUNOLOGICAL ABNORMALITIES, GENETIC RISK FOCI, EPIGENETIC MODIFICATION AND ENVIRONMENTAL FACTORS OF PSORIASIS. WITH ADVANCES IN MOLECULAR BIOLOGY, DIVERSE NEW TARGETS ARE UNDER INVESTIGATION TO MANAGE PSORIASIS. THE RECENT ADVANCES IN TREATMENT MODALITIES FOR PSORIASIS BASED ON TARGETED MOLECULES ARE ALSO DISCUSSED. 2017 20 3031 33 GENETICS OF RHEUMATOID ARTHRITIS. RHEUMATOID ARTHRITIS (RA) IS AN INFLAMMATORY AUTOIMMUNE DISEASE INVOLVING SYMMETRIC JOINTS AND IS GENERALLY CHARACTERIZED BY PERSISTENT PAIN, TENDERNESS, AND DESTRUCTION OF JOINTS. THE VAST MAJORITY OF RA PATIENTS PRODUCE AUTOANTIBODIES, AND IMMUNE CELL INVOLVEMENT IN DISEASE DEVELOPMENT IS WELL RECOGNIZED, AS IS THE CONTRIBUTION OF OTHER TYPES OF CELLS IN SYNOVIAL TISSUE, LIKE FIBROBLASTS. IT IS KNOWN THAT THERE ARE MAJOR GENETIC ASSOCIATIONS WITH THE HLA LOCUS, WHILE MULTIPLE NON-HLA GENETIC VARIANTS DISPLAY RELATIVELY LOW RISK OF RA. BOTH HLA AND NON-HLA ASSOCIATIONS SUGGEST THAT THE PROFILES OF GENETIC ASSOCIATIONS FOR AUTOANTIBODY-POSITIVE VS. AUTOANTIBODY-NEGATIVE RA ARE DIFFERENT. SEVERAL ALLELES OF HLA-DRB1 ARE ASSOCIATED WITH HIGH RISK FOR AUTOANTIBODY-POSITIVE RA, WITH THE STRONGEST RISK CHARACTERIZED BY VALINE AT POSITION 11 OF THE PROTEIN SEQUENCE (HLA-DRB1*04 AND *10 ALLELES). THERE IS A STRONG PROTECTIVE EFFECT FOR THE RISK OF AUTOANTIBODY-POSITIVE RA ASSOCIATED WITH HLA-DRB1*13 ALLELES. ALTHOUGH MAJOR GENETIC ASSOCIATIONS HAVE BEEN KNOWN FOR SEVERAL YEARS, UNDERSTANDING OF THE SPECIFIC MECHANISMS IN THE DEVELOPMENT OF INCREASED RISK OF RA FOR THESE VARIATIONS IS WORK IN PROGRESS. CURRENT STUDIES FOCUS ON THE BINDING OF IMMUNE RECEPTORS INVOLVED IN RECOGNITION OF PUTATIVE PEPTIDES IN ACTIVATION OF T CELLS, AS WELL AS INVESTIGATION OF CELL SIGNALING MECHANISMS. AT LEAST A PART OF RA RISK COULD BE EXPLAINED BY GENE-GENE AND GENE-ENVIRONMENT INTERACTIONS. THERE ARE CURRENTLY MORE THAN 150 CANDIDATE LOCI WITH POLYMORPHISMS THAT ASSOCIATE WITH RA, MAINLY RELATED TO SEROPOSITIVE DISEASE, AND NEW DISCOVERIES ARE ANTICIPATED IN THE FUTURE FROM INVESTIGATION OF DIVERSE HUMAN POPULATIONS. THIS NEW RESEARCH WILL HELP CREATE A STRONG FOUNDATION FOR THE CONTINUING PROCESS OF INTEGRATING GENETIC, EPIGENETIC, TRANSCRIPTOMIC, AND PROTEOMIC DATA IN STUDIES OF RA. 2022