1 4952 125 PATHOGENESIS OF CHRONIC CHIKUNGUNYA ARTHRITIS: RESEMBLANCES AND LINKS WITH RHEUMATOID ARTHRITIS. CHIKUNGUNYA VIRUS (CHIKV) INFECTION RESULTS FROM TRANSMISSION BY THE MOSQUITO VECTOR. FOLLOWING AN INCUBATION PERIOD OF 5-7 DAYS, PATIENTS DEVELOP AN ACUTE FEBRILE ILLNESS, CHIKUNGUNYA FEVER (CHIKF), CHARACTERIZED BY HIGH FEVERS, MACULOPAPULAR RASH, HEADACHES, POLYARTHRITIS/ARTHRALGIAS, MYALGIAS, NAUSEA, VOMITING, AND DIARRHEA. JOINT PAIN IS OFTEN SEVERE, AND MOST OFTEN INVOLVES THE HANDS, THE WRISTS, THE ANKLES, AND THE METATARSAL-PHALANGEAL JOINTS OF THE FEET. MANY PATIENTS RECOVER WITHIN SEVERAL WEEKS, BUT UP TO 50% DEVELOP CHRONIC JOINT PAIN AND SWELLING FOR MORE THAN 12 WEEKS, THEN WE REFER TO THESE SYMPTOMS AS CHRONIC CHIKUNGUNYA ARTHRITIS (CCA). THE PATHOGENESIS OF CCA IS NOT WELL UNDERSTOOD. IN THIS ARTICLE, WE SUGGEST THAT MESENCHYMAL STEM CELLS (MSCS) MAY PLAY AN IMPORTANT ROLE IN THIS PATHOGENESIS. THIS HETEROGENEOUS GROUP OF MULTIPOTENT CELLS, MORPHOLOGICALLY SIMILAR TO FIBROBLASTS, MAY UNDERGO EPIGENETIC CHANGES CAPABLE OF GENERATING ABERRANT PROGENIES. HOWEVER, WE BELIEVE THAT THERE IS NO NEED FOR A LATENT INFECTION. IN OUR PATHOGENIC HYPOTHESIS, CHIKV INFECTION OF MSCS WOULD CAUSE EPIGENETIC CHANGES BOTH IN MSCS THEMSELVES AND IN THEIR PROGENIES, WITHOUT THE NEED FOR REACTIVATION OF DORMANT VIRUSES. 2023 2 4968 31 PATHOLOGICAL MECHANISMS AND THERAPEUTIC OUTLOOKS FOR ARTHROFIBROSIS. ARTHROFIBROSIS IS A FIBROTIC JOINT DISORDER THAT BEGINS WITH AN INFLAMMATORY REACTION TO INSULTS SUCH AS INJURY, SURGERY AND INFECTION. EXCESSIVE EXTRACELLULAR MATRIX AND ADHESIONS CONTRACT POUCHES, BURSAE AND TENDONS, CAUSE PAIN AND PREVENT A NORMAL RANGE OF JOINT MOTION, WITH DEVASTATING CONSEQUENCES FOR PATIENT QUALITY OF LIFE. ARTHROFIBROSIS AFFECTS PEOPLE OF ALL AGES, WITH PUBLISHED RATES VARYING. THE RISK FACTORS AND BEST MANAGEMENT STRATEGIES ARE LARGELY UNKNOWN DUE TO A POOR UNDERSTANDING OF THE PATHOLOGY AND LACK OF DIAGNOSTIC BIOMARKERS. HOWEVER, CURRENT RESEARCH INTO THE PATHOGENESIS OF FIBROSIS IN ORGANS NOW INFORMS THE UNDERSTANDING OF ARTHROFIBROSIS. THE PROCESS BEGINS WHEN STRESS SIGNALS STIMULATE IMMUNE CELLS. THE RESULTING CASCADE OF CYTOKINES AND MEDIATORS DRIVES FIBROBLASTS TO DIFFERENTIATE INTO MYOFIBROBLASTS, WHICH SECRETE FIBRILLAR COLLAGENS AND TRANSFORMING GROWTH FACTOR-BETA (TGF-BETA). POSITIVE FEEDBACK NETWORKS THEN DYSREGULATE PROCESSES THAT NORMALLY TERMINATE HEALING PROCESSES. WE PROPOSE TWO SUBTYPES OF ARTHROFIBROSIS OCCUR: ACTIVE ARTHROFIBROSIS AND RESIDUAL ARTHROFIBROSIS. IN THE LATTER THE FIBROGENIC PROCESSES HAVE RESOLVED BUT THE JOINT REMAINS STIFF. THE BEST THERAPEUTIC APPROACH FOR EACH SUBTYPE MAY DIFFER SIGNIFICANTLY. TREATMENT TYPICALLY INVOLVES SURGERY, HOWEVER, A PHARMACOLOGICAL APPROACH TO CORRECT DYSREGULATED CELL SIGNALLING COULD BE MORE EFFECTIVE. RECENT RESEARCH SHOWS THAT MYOFIBROBLASTS ARE CAPABLE OF REVERSING DIFFERENTIATION, AND UNDERSTANDING THE MECHANISMS OF PATHOGENESIS AND RESOLUTION WILL BE ESSENTIAL FOR THE DEVELOPMENT OF CELL-BASED TREATMENTS. THERAPIES WITH SIGNIFICANT PROMISE ARE CURRENTLY AVAILABLE, WITH MORE IN DEVELOPMENT, INCLUDING THOSE THAT INHIBIT TGF-BETA SIGNALLING AND EPIGENETIC MODIFICATIONS. THIS REVIEW FOCUSES ON PATHOGENESIS OF STERILE ARTHROFIBROSIS AND THERAPEUTIC TREATMENTS. 2019 3 5153 21 PPP2R2B HYPERMETHYLATION CAUSES ACQUIRED APOPTOSIS DEFICIENCY IN SYSTEMIC AUTOIMMUNE DISEASES. CHRONIC INFLAMMATION CAUSES TARGET ORGAN DAMAGE IN PATIENTS WITH SYSTEMIC AUTOIMMUNE DISEASES. THE FACTORS THAT ALLOW THIS PROTRACTED RESPONSE ARE POORLY UNDERSTOOD. WE ANALYZED THE TRANSCRIPTIONAL REGULATION OF PPP2R2B (B55SS), A MOLECULE NECESSARY FOR THE TERMINATION OF THE IMMUNE RESPONSE, IN PATIENTS WITH AUTOIMMUNE DISEASES. ALTERED EXPRESSION OF B55SS CONDITIONED RESISTANCE TO CYTOKINE WITHDRAWAL-INDUCED DEATH (CWID) IN PATIENTS WITH AUTOIMMUNE DISEASES. THE IMPAIRED UPREGULATION OF B55SS WAS CAUSED BY INFLAMMATION-DRIVEN HYPERMETHYLATION OF SPECIFIC CYTOSINES LOCATED WITHIN A REGULATORY ELEMENT OF PPP2R2B PREVENTING CTCF BINDING. THIS PHENOTYPE COULD BE INDUCED IN HEALTHY T CELLS BY EXPOSURE TO TNF-ALPHA. OUR RESULTS REVEAL A GENE WHOSE EXPRESSION IS AFFECTED BY AN ACQUIRED DEFECT, THROUGH AN EPIGENETIC MECHANISM, IN THE SETTING OF SYSTEMIC AUTOIMMUNITY. BECAUSE FAILURE TO REMOVE ACTIVATED T CELLS THROUGH CWID COULD CONTRIBUTE TO AUTOIMMUNE PATHOLOGY, THIS MECHANISM ILLUSTRATES A VICIOUS CYCLE THROUGH WHICH AUTOIMMUNE INFLAMMATION CONTRIBUTES TO ITS OWN PERPETUATION. 2019 4 3899 29 LATE NEUROLOGICAL CONSEQUENCES OF ZIKA VIRUS INFECTION: RISK FACTORS AND PHARMACEUTICAL APPROACHES. ZIKA VIRUS (ZIKV) INFECTION WAS HISTORICALLY CONSIDERED A DISEASE WITH MILD SYMPTOMS AND NO MAJOR CONSEQUENCES TO HUMAN HEALTH. HOWEVER, SEVERAL LONG-TERM, LATE ONSET, AND CHRONIC NEUROLOGICAL COMPLICATIONS, BOTH IN CONGENITALLY-EXPOSED BABIES AND IN ADULT PATIENTS, HAVE BEEN REPORTED AFTER ZIKV INFECTION, ESPECIALLY AFTER THE 2015 EPIDEMICS IN THE AMERICAN CONTINENT. THE DEVELOPMENT OR SEVERITY OF THESE CONDITIONS CANNOT BE FULLY PREDICTED, BUT IT IS POSSIBLE THAT GENETIC, EPIGENETIC, AND ENVIRONMENTAL FACTORS MAY CONTRIBUTE TO DETERMINE ZIKV INFECTION OUTCOMES. THIS REINFORCES THE IMPORTANCE THAT INDIVIDUALS EXPOSED TO ZIKV ARE SUBMITTED TO LONG-TERM CLINICAL SURVEILLANCE AND HIGHLIGHTS THE URGENT NEED FOR THE DEVELOPMENT OF THERAPEUTIC APPROACHES TO REDUCE OR ELIMINATE THE NEUROLOGICAL BURDEN OF INFECTION. HERE, WE REVIEW THE EPIDEMIOLOGY OF ZIKV-ASSOCIATED NEUROLOGICAL COMPLICATIONS AND THE ROLE OF FACTORS THAT MAY INFLUENCE DISEASE OUTCOME. MOREOVER, WE DISCUSS EXPERIMENTAL AND CLINICAL EVIDENCE OF DRUGS THAT HAVE SHOWN PROMISING RESULTS IN VITRO OR IN VITRO AGAINST VIRAL REPLICATION AND AND/OR ZIKV-INDUCED NEUROTOXICITY. 2019 5 4665 21 NEW INSIGHTS AND ADVANCES IN PATHOGENESIS AND TREATMENT OF VERY EARLY ONSET INFLAMMATORY BOWEL DISEASE. VERY EARLY ONSET INFLAMMATORY BOWEL DISEASE (VEO-IBD) IS CHARACTERIZED BY MULTIFACTORIAL CHRONIC RECURRENT INTESTINAL INFLAMMATION. COMPARED WITH ELDERLY PATIENTS, THOSE WITH VEO-IBD HAVE A MORE SERIOUS CONDITION, NOT RESPONSIVE TO CONVENTIONAL TREATMENTS, WITH A POOR PROGNOSIS. RECENT STUDIES FOUND THAT GENETIC AND IMMUNOLOGIC ABNORMALITIES ARE CLOSELY RELATED TO VEO-IBD. INTESTINAL IMMUNE HOMEOSTASIS MONOGENIC DEFECTS (IIHMDS) ARE CHANGED THROUGH VARIOUS MECHANISMS. RECENT STUDIES HAVE ALSO REVEALED THAT ABNORMALITIES IN GENES AND IMMUNE MOLECULAR MECHANISMS ARE CLOSELY RELATED TO VEO-IBD. IIHMDS CHANGE THROUGH VARIOUS MECHANISMS. EPIGENETIC FACTORS CAN MEDIATE THE INTERACTION BETWEEN THE ENVIRONMENT AND GENOME, AND GENETIC FACTORS AND IMMUNE MOLECULES MAY BE INVOLVED IN THE PATHOGENESIS OF THE ENVIRONMENT AND GUT MICROBIOTA. THESE DISCOVERIES WILL PROVIDE NEW DIRECTIONS AND IDEAS FOR THE TREATMENT OF VEO-IBD. 2022 6 4012 24 LOW-DENSITY GRANULOCYTES IN SYSTEMIC AUTOIMMUNITY AND AUTOINFLAMMATION. A BODY OF EVIDENCE HAS RE-ENERGIZED THE INTEREST ON THE ROLE NEUTROPHILS IN INFLAMMATORY AND AUTOIMMUNE CONDITIONS. FOR DECADES, NEUTROPHILS HAVE BEEN CONSIDERED A HOMOGENOUS POPULATION. NEVERTHELESS, ACCUMULATING EVIDENCE SUGGESTS THAT NEUTROPHILS ARE MORE VERSATILE AND HETEROGENEOUS THAN INITIALLY CONSIDERED. THE NOTION OF NEUTROPHIL HETEROGENEITY HAS BEEN SUPPORTED BY THE IDENTIFICATION OF LOW-DENSITY GRANULOCYTES (LDGS) IN SYSTEMIC LUPUS ERYTHEMATOSUS (SLE) AND OTHER SYSTEMIC AUTOIMMUNE AND AUTOINFLAMMATORY CONDITIONS. TRANSCRIPTOMIC, EPIGENETIC, PROTEOMIC, AND FUNCTIONAL ANALYSES SUPPORT THAT LDGS ARE A DISTINCT SUBSET OF PROINFLAMMATORY NEUTROPHILS IMPLICATED IN THE PATHOGENESIS OF SLE AND OTHER AUTOIMMUNE DISEASES. IMPORTANTLY, IT REMAINS INCOMPLETELY CHARACTERIZED WHETHER LDGS DETECTED IN OTHER INFLAMMATORY/AUTOIMMUNE CONDITIONS DISPLAY THE SAME PHENOTYPE THAT THOSE PRESENT IN SLE. A SHARED FEATURE OF LDGS ACROSS DISEASES IS THEIR ASSOCIATION WITH VASCULAR DAMAGE, AN IMPORTANT CONTRIBUTOR TO MORBIDITY AND MORTALITY IN CHRONIC INFLAMMATORY CONDITIONS. ADDITIONALLY, THE LACK OF SPECIFIC MARKERS TO IDENTIFY LDGS IN CIRCULATION OR IN TISSUE, MAKES IT A CHALLENGE TO ELUCIDATE THEIR ROLE IN THE PATHOGENESIS OF INFLAMMATORY AND AUTOIMMUNE CONDITIONS. IN THIS REVIEW, WE AIM TO EXAMINE THE EVIDENCE ON THE BIOLOGY AND THE PUTATIVE PATHOGENIC ROLE OF LDGS IN SYSTEMIC AUTOIMMUNE DISEASES. 2023 7 5464 23 RESILIENCE IN LONG-TERM VIRAL INFECTION: GENETIC DETERMINANTS AND INTERACTIONS. VIRUS-INDUCED NEUROLOGICAL SEQUELAE RESULTING FROM INFECTION BY THEILER'S MURINE ENCEPHALOMYELITIS VIRUS (TMEV) ARE USED FOR STUDYING HUMAN CONDITIONS RANGING FROM EPILEPTIC SEIZURES TO DEMYELINATING DISEASE. MOUSE STRAINS ARE TYPICALLY CONSIDERED SUSCEPTIBLE OR RESISTANT TO TMEV INFECTION BASED ON VIRAL PERSISTENCE AND EXTREME PHENOTYPES, SUCH AS DEMYELINATION. WE HAVE IDENTIFIED A BROADER SPECTRUM OF PHENOTYPIC OUTCOMES BY INFECTING STRAINS OF THE GENETICALLY DIVERSE COLLABORATIVE CROSS (CC) MOUSE RESOURCE. WE EVALUATED THE CHRONIC-INFECTION GENE EXPRESSION PROFILES OF HIPPOCAMPI AND THORACIC SPINAL CORDS FOR 19 CC STRAINS IN RELATION TO PHENOTYPIC SEVERITY AND TMEV PERSISTENCE. STRAINS WERE CLUSTERED BASED ON SIMILAR PHENOTYPIC PROFILES AND TMEV LEVELS AT 90 DAYS POST-INFECTION, AND WE CATEGORIZED DISTINCT TMEV RESPONSE PROFILES. THE THREE MOST COMMON PROFILES INCLUDED "RESISTANT" AND "SUSCEPTIBLE," AS BEFORE, AS WELL AS A "RESILIENT" TMEV RESPONSE GROUP WHICH EXPERIENCED BOTH TMEV PERSISTENCE AND MILD NEUROLOGICAL PHENOTYPES EVEN AT 90 DAYS POST-INFECTION. EACH PROFILE HAD A DISTINCT GENE EXPRESSION SIGNATURE, ALLOWING THE IDENTIFICATION OF PATHWAYS AND NETWORKS SPECIFIC TO EACH TMEV RESPONSE GROUP. CC FOUNDER HAPLOTYPES FOR GENES INVOLVED IN THESE PATHWAYS/NETWORKS REVEALED CANDIDATE RESPONSE-SPECIFIC ALLELES. THESE ALLELES DEMONSTRATED PLEIOTROPY AND EPIGENETIC (MIRNA) REGULATION IN LONG-TERM TMEV INFECTION, WITH PARTICULAR RELEVANCE FOR RESILIENT MOUSE STRAINS. 2021 8 2568 27 EPIGENETICS OF ALCOHOL-RELATED LIVER DISEASES. ALCOHOL-RELATED LIVER DISEASE (ARLD) IS A PRIMARY CAUSE OF CHRONIC LIVER DISEASE IN THE UNITED STATES. DESPITE ADVANCES IN THE DIAGNOSIS AND MANAGEMENT OF ARLD, IT REMAINS A MAJOR PUBLIC HEALTH PROBLEM ASSOCIATED WITH SIGNIFICANT MORBIDITY AND MORTALITY, EMPHASISING THE NEED TO ADOPT NOVEL APPROACHES TO THE STUDY OF ARLD AND ITS COMPLICATIONS. EPIGENETIC CHANGES ARE INCREASINGLY BEING RECOGNISED AS CONTRIBUTING TO THE PATHOGENESIS OF MULTIPLE DISEASE STATES. HARNESSING THE POWER OF INNOVATIVE TECHNOLOGIES FOR THE STUDY OF EPIGENETICS (E.G., NEXT-GENERATION SEQUENCING, DNA METHYLATION ASSAYS, HISTONE MODIFICATION PROFILING AND COMPUTATIONAL TECHNIQUES LIKE MACHINE LEARNING) HAS RESULTED IN A SEISMIC SHIFT IN OUR UNDERSTANDING OF THE PATHOPHYSIOLOGY OF ARLD. KNOWLEDGE OF THESE TECHNIQUES AND ADVANCES IS OF PARAMOUNT IMPORTANCE FOR THE PRACTICING HEPATOLOGIST AND RESEARCHERS ALIKE. ACCORDINGLY, IN THIS REVIEW ARTICLE WE WILL SUMMARISE THE CURRENT KNOWLEDGE ABOUT ALCOHOL-INDUCED EPIGENETIC ALTERATIONS IN THE CONTEXT OF ARLD, INCLUDING BUT NOT LIMITED TO, DNA HYPER/HYPO METHYLATION, HISTONE MODIFICATIONS, CHANGES IN NON-CODING RNA, 3D CHROMATIN ARCHITECTURE AND ENHANCER-PROMOTER INTERACTIONS. ADDITIONALLY, WE WILL DISCUSS THE STATE-OF-THE-ART TECHNIQUES USED IN THE STUDY OF ARLD (E.G. SINGLE-CELL SEQUENCING). WE WILL ALSO HIGHLIGHT THE EPIGENETIC REGULATION OF CHEMOKINES AND THEIR PROINFLAMMATORY ROLE IN THE CONTEXT OF ARLD. LASTLY, WE WILL EXAMINE THE CLINICAL APPLICATIONS OF EPIGENETICS IN THE DIAGNOSIS AND MANAGEMENT OF ARLD. 2022 9 1643 29 DOES RHEUMATOID ARTHRITIS REPRESENT AN ADAPTIVE, THRIFTY CONDITION? THE PRESENT ARTICLE PRESENTS EPIDEMIOLOGICAL, AND COMPARATIVE EVIDENCE SUPPORTING THE HYPOTHESIS THAT RHEUMATOID ARTHRITIS (RA) MAY REPRESENT A THRIFTY ADAPTATION SELECTED TO COMPEL ANIMALS TO MINIMIZE VOLUNTARY ENERGY EXPENDITURE. THE AUTOIMMUNE, PATHOPHYSIOLOGICAL MANIFESTATIONS UNDERLYING RA ARE FRAMED HERE AS CONSTITUTING AN EVOLVED, PROTECTIVE MECHANISM THAT WOULD HAVE INFLUENCED ANIMALS TO AVOID EXERTION AND MAINTAIN A SEDENTARY LIFESTYLE IN ORDER TO MINIMIZE METABOLIC OUTPUT AND ULTIMATELY ESCAPE STARVATION. ARTHRITIC PAIN IS CHARACTERIZED HERE AS A DEFENSIVE, INNATE SIGNAL MUCH LIKE FATIGUE, FEVER, NAUSEA AND REFLEXIVE PAIN, AND LIKE THESE, IS SEEN ON A CONTINUUM VARYING BETWEEN IMPERCEPTIBLE ENCUMBRANCE AND DEBILITATING DISABILITY. THE EPIGENETIC RELATIONSHIP BETWEEN ACUTE PSYCHOLOGICAL STRESS AND FLARE-UP OF ARTHRITIC SYMPTOMS IS EXAMINED AND TAKEN TO SUGGEST THAT ARTHRITIS MAY BE A PREDICTIVE, ADAPTIVE RESPONSE TO SEVERE STRESS ALLOWING REDUCTIONS IN METABOLISM TO FOLLOW ADVERSE CONDITIONS OR NUTRITIONAL SCARCITY. THE CLOSE ASSOCIATIONS BETWEEN RHEUMATOID ARTHRITIS AND THE METABOLIC SYNDROME ARE ALSO EXPLORED ALONG WITH POTENTIAL TIES TO THE "THRIFTY GENOTYPE" AND "THRIFTY PHENOTYPE" PHENOMENA. THIS HYPOTHESIS IS EXAMINED IN THE CONTEXTS OF EVOLUTIONARY MEDICINE, PHENOTYPIC PLASTICITY, THE STRESS RESPONSE AND THE BIOENERGETICS OF THRIFT. A BRIEF AND EXPLORATORY REVIEW OF PERTINENT EVIDENCE SUGGESTS THAT RA, ITS SUBCLINICAL MANIFESTATIONS, AND EVEN OTHER FORMS OF ARTHROPATHY MAY POSSIBLY REPRESENT ADAPTATIONS THAT PROMOTED METABOLIC THRIFT DURING OUR EVOLUTIONARY PAST. 2010 10 3959 29 LONG NON-CODING RNAS TARGET PATHOGENETICALLY RELEVANT GENES AND PATHWAYS IN RHEUMATOID ARTHRITIS. RHEUMATOID ARTHRITIS (RA) IS A CHRONIC INFLAMMATORY AUTOIMMUNE DISEASE DRIVEN BY GENETIC, ENVIRONMENTAL AND EPIGENETIC FACTORS. LONG NON-CODING RNAS (LNCRNAS) ARE A KEY COMPONENT OF THE EPIGENETIC MECHANISMS AND ARE KNOWN TO BE INVOLVED IN THE DEVELOPMENT OF AUTOIMMUNE DISEASES. IN THIS WORK WE AIMED TO IDENTIFY SIGNIFICANTLY DIFFERENTIALLY EXPRESSED LNCRNAS (DE-LNCRNAS) THAT ARE FUNCTIONALLY CONNECTED TO MODULATED GENES STRICTLY ASSOCIATED WITH RA. IN TOTAL, 542,500 TRANSCRIPTS HAVE BEEN PROFILED IN PERIPHERAL BLOOD MONONUCLEAR CELLS (PBMCS) FROM FOUR PATIENTS WITH EARLY ONSET RA PRIOR ANY TREATMENT AND FOUR HEALTHY DONORS USING CLARIOM D ARRAYS. RESULTS WERE CONFIRMED BY REAL-TIME PCR IN 20 PATIENTS AND 20 CONTROLS. SIX DE-LNCRNAS TARGET EXPERIMENTALLY VALIDATED MIRNAS ABLE TO REGULATE DIFFERENTIALLY EXPRESSED GENES (DEGS) IN RA; AMONG THEM, ONLY FTX, HNRNPU-AS1 AND RP11-498C9.15 TARGETED A LARGE NUMBER OF DEGS. MOST IMPORTANTLY, RP11-498C9.15 TARGETED THE LARGEST NUMBER OF SIGNALLING PATHWAYS THAT WERE FOUND TO BE ENRICHED BY THE GLOBAL AMOUNT OF RA-DEGS AND THAT HAVE ALREADY BEEN ASSOCIATED WITH RA AND RA-SYNOVIOCYTES. MOREOVER, RP11-498C9.15 TARGETED THE MOST HIGHLY CONNECTED GENES IN THE RA INTERACTOME, THUS SUGGESTING ITS INVOLVEMENT IN CRUCIAL GENE REGULATION. THESE RESULTS INDICATE THAT, BY MODULATING BOTH MICRORNAS AND GENE EXPRESSION, RP11-498C9.15 MAY PLAY A PIVOTAL ROLE IN RA PATHOGENESIS. 2019 11 5433 19 REL/NF-KAPPA B/I KAPPA B SIGNAL TRANSDUCTION IN THE GENERATION AND TREATMENT OF HUMAN CANCER. THE REL/NF-KAPPA B FAMILY IS A GROUP OF STRUCTURALLY-RELATED, TIGHTLY-REGULATED TRANSCRIPTION FACTORS THAT CONTROL THE EXPRESSION OF A MULTITUDE OF GENES INVOLVED IN KEY CELLULAR AND ORGANISMAL PROCESSES. THE REL/NF-KAPPA B SIGNAL TRANSDUCTION PATHWAY IS MISREGULATED IN A VARIETY OF HUMAN CANCERS, ESPECIALLY ONES OF LYMPHOID CELL ORIGIN, DUE EITHER TO GENETIC CHANGES (SUCH AS CHROMOSOMAL REARRANGEMENTS, AMPLIFICATIONS, AND MUTATIONS) OR TO CHRONIC ACTIVATION OF THE PATHWAY BY EPIGENETIC MECHANISMS. CONSTITUTIVE ACTIVATION OF THE REL/NF-KAPPA B PATHWAY CAN CONTRIBUTE TO THE ONCOGENIC STATE IN SEVERAL WAYS, FOR EXAMPLE, BY DRIVING PROLIFERATION, BY ENHANCING CELL SURVIVAL, OR BY PROMOTING ANGIOGENESIS OR METASTASIS. IN MANY CASES, INHIBITION OF REL/NF-KAPPA B ACTIVITY REVERSES ALL OR PART OF THE MALIGNANT STATE. THUS, THE REL/NF-KAPPA B PATHWAY HAS RECEIVED MUCH ATTENTION AS A FOCAL POINT FOR CLINICAL INTERVENTION. 2002 12 3537 32 IMMUNE DYSREGULATION IN KABUKI SYNDROME: A CASE REPORT OF EVANS SYNDROME AND HYPOGAMMAGLOBULINEMIA. KABUKI SYNDROME (KS) IS A RARE MULTISYSTEMIC DISEASE DUE TO MUTATIONS IN THE KMT2D OR KDM6A GENES, WHICH ACT AS EPIGENETIC MODULATORS OF DIFFERENT PROCESSES, INCLUDING IMMUNE RESPONSE. THE SYNDROME IS CHARACTERIZED BY ANOMALIES IN MULTIPLE ORGAN SYSTEMS, AND IT IS ASSOCIATED WITH AUTOIMMUNE AND INFLAMMATORY DISORDERS, AND AN UNDERLYING IMMUNOLOGICAL PHENOTYPE CHARACTERIZED BY IMMUNODEFICIENCY AND IMMUNE DYSREGULATION. UP TO 17% OF KS PATIENTS PRESENT WITH IMMUNE THROMBOCYTOPENIA CHARACTERIZED BY A SEVERE, CHRONIC OR RELAPSING COURSE, AND OFTEN ASSOCIATED TO OTHER HEMATOLOGICAL AUTOIMMUNE DISEASES INCLUDING AUTOIMMUNE HEMOLYTIC ANEMIA, EVENTUALLY RESULTING IN EVANS SYNDROME (ES). A 23-YEAR-OLD WOMAN, CLINICALLY DIAGNOSED WITH KS AND PRESENTING FROM THE AGE OF 3 YEARS WITH ES WAS REFERRED TO THE RARE DISEASES CENTRE OF OUR PEDIATRIC DEPARTMENT FOR CORTICOSTEROID-INDUCED HYPERGLYCEMIA. SEVERAL ES RELAPSES AND RECURRENT RESPIRATORY INFECTIONS IN THE PREVIOUS YEARS WERE REPORTED. SEVERE HYPOGAMMAGLOBULINEMIA, SPLENOMEGALY AND SIGNS OF CHRONIC LUNG INFLAMMATION WERE DIAGNOSED ONLY AT THE TIME OF OUR OBSERVATION. SUPPORTIVE TREATMENT WITH AMOXICILLIN-CLAVULANATE PROPHYLAXIS AND RECOMBINANT HUMAN HYALURONIDASE-FACILITATED SUBCUTANEOUS IMMUNOGLOBULIN REPLACEMENT WERE IMMEDIATELY STARTED. IN KS PATIENTS, THE FAILURE OF B-CELL DEVELOPMENT AND THE LACK OF AUTOREACTIVE IMMUNE CELLS SUPPRESSION CAN LEAD TO IMMUNODEFICIENCY AND AUTOIMMUNITY THAT MAY BE UNDIAGNOSED FOR A LONG TIME. OUR PATIENT'S CASE IS PARADIGMATIC SINCE SHE PRESENTED WITH PREVENTABLE MORBIDITY AND SEVERE LUNG DISEASE YEARS AFTER DISEASE ONSET. THIS CASE EMPHASIZES THE IMPORTANCE OF SUSPECTING IMMUNE DYSREGULATION IN KS. PATHOGENESIS AND IMMUNOLOGICAL COMPLICATIONS OF KS ARE DISCUSSED. MOREOVER, THE NEED TO PERFORM IMMUNOLOGIC EVALUATIONS IS HIGHLIGHTED BOTH AT THE TIME OF KS DIAGNOSIS AND DURING DISEASE FOLLOW-UP, IN ORDER TO ALLOW PROPER TREATMENT WHILE INTERCEPTING AVOIDABLE MORBIDITY IN THESE PATIENTS. 2023 13 6584 20 TRIGGERING RECEPTORS EXPRESSED ON MYELOID CELLS 1 : OUR NEW PARTNER IN HUMAN ONCOLOGY? INFLAMMATION IS RECOGNIZED AS ONE OF THE HALLMARKS OF CANCER. INDEED, STRONG EVIDENCE INDICATES THAT CHRONIC INFLAMMATION PLAYS A MAJOR ROLE IN ONCOGENESIS, PROMOTING GENOME INSTABILITY, EPIGENETIC ALTERATIONS, PROLIFERATION AND DISSEMINATION OF CANCER CELLS. MONONUCLEAR PHAGOCYTES (MPS) HAVE BEEN IDENTIFIED AS KEY CONTRIBUTORS OF THE INFLAMMATORY INFILTRATE IN SEVERAL SOLID HUMAN NEOPLASIA, PROMOTING ANGIOGENESIS AND CANCER PROGRESSION. ONE OF THE MOST DESCRIBED AMPLIFIERS OF MPS PRO-INFLAMMATORY INNATE IMMUNE RESPONSE IS THE TRIGGERING RECEPTORS EXPRESSED ON MYELOID CELLS 1 (TREM-1). GROWING EVIDENCE SUGGESTS TREM-1 INVOLVEMENT IN ONCOGENESIS THROUGH CANCER RELATED INFLAMMATION AND THE SURROUNDING TUMOR MICROENVIRONMENT. IN HUMAN ONCOLOGY, HIGH LEVELS OF TREM-1 AND/OR ITS SOLUBLE FORM HAVE BEEN ASSOCIATED WITH POORER SURVIVAL DATA IN SEVERAL SOLID MALIGNANCIES, ESPECIALLY IN HEPATOCELLULAR CARCINOMA AND LUNG CANCER. TREM-1 SHOULD BE CONSIDERED AS A POTENTIAL BIOMARKER IN HUMAN ONCOLOGY AND COULD BE USED AS A NEW THERAPEUTIC TARGET OF INTEREST IN HUMAN ONCOLOGY (TREM-1 INHIBITORS, TREM-1 AGONISTS). MORE CLINICAL STUDIES ARE URGENTLY NEEDED TO CONFIRM TREM-1 (AND TREM FAMILY) ROLES IN THE PROGNOSIS AND THE TREATMENT OF HUMAN SOLID CANCERS. 2022 14 4834 24 ON THE INTERPLAY BETWEEN THE MEDICINE OF HILDEGARD OF BINGEN AND MODERN MEDICINE: THE ROLE OF ESTROGEN RECEPTOR AS AN EXAMPLE OF BIODYNAMIC INTERFACE FOR STUDYING THE CHRONIC DISEASE'S COMPLEXITY. INTRODUCTION: HILDEGARD OF BINGEN (1098-1179) INTERPRETED THE ORIGINS OF CHRONIC DISEASE HIGHLIGHTING AND ANTICIPATING, ALTHOUGH ONLY IN A LIMITED FASHION, THE IMPORTANCE THAT COMPLEX INTERACTIONS AMONG NUMEROUS GENETIC, INTERNAL MILIEU AND EXTERNAL ENVIRONMENTAL FACTORS HAVE IN DETERMINING THE DISEASE PHENOTYPE. TODAY, WE RECOGNIZE THOSE FACTORS, CAPABLE OF MEDIATING THE TRANSMISSION OF MESSAGES BETWEEN HUMAN BODY AND ENVIRONMENT AND VICE VERSA, AS BIODYNAMIC INTERFACES. AIM: WE ANALYZED, IN THE LIGHT OF MODERN SCIENTIFIC EVIDENCE, HILDEGARD OF BINGEN'S MEDICAL APPROACH AND HER ORIGINAL HUMORAL THEORY IN ORDER TO IDENTIFY POSSIBLE INSIGHTS INCLUDED IN HER MEDICINE THAT COULD BE REFERRED TO IN THE CONTEXT OF MODERN EVIDENCE-BASED MEDICINE. IN PARTICULAR, THE ABBESS'S HUMORAL THEORY SUGGESTS THE IDENTIFICATION OF BIODYNAMIC INTERFACES WITH SEX HORMONES AND THEIR RECEPTORS. FINDINGS: WE FOUND THAT THE HILDEGARDIAN HOLISTIC VISION OF THE ORGANISM-ENVIRONMENT RELATIONSHIP CAN ACTUALLY REPRESENT A VISIONARY APPROACH TO MODERN ENDOCRINOLOGY AND THAT SEX HORMONES, IN PARTICULAR ESTROGENS, COULD REPRESENT AN EXAMPLE OF A BIODYNAMIC INTERFACE. ESTROGEN RECEPTORS ARE FOUND IN REGIONS OF THE BRAIN INVOLVED IN EMOTIONAL AND COGNITIVE REGULATION, CONTROLLING THE MOLECULAR MECHANISM OF BRAIN FUNCTION. ESTROGEN RECEPTORS ARE INVOLVED IN THE REGULATION OF THE HYPOTHALAMIC-PITUITARY-ADRENAL AXIS AND IN THE EPIGENETIC REGULATION OF RESPONSES TO PHYSIOLOGICAL, SOCIAL, AND HORMONAL STIMULI. FURTHERMORE, ESTROGEN AFFECTS GENE METHYLATION ON ITS OWN AND RELATED RECEPTOR PROMOTERS IN DISCRETE REGIONS OF THE DEVELOPING BRAIN. THIS SCENARIO WAS STRIKINGLY PERCEIVED BY THE ABBESS IN THE XIITH CENTURY, AND DEPICTED AS A COMPLEX INTERPLAY AMONG DIFFERENT HUMORS AND FLEGMATA THAT SHE RECOGNIZED TO BE SEX SPECIFIC AND ENVIRONMENTALLY REGULATED. VIEWPOINT: CONSIDERING THE FUNCTION PLAYED BY HORMONES, ANALYZED THROUGH THE LAST SCIENTIFIC EVIDENCE, AND SCIENTIFIC LITERATURE ON BIODYNAMIC INTERFACES, WE COULD SUGGEST HILDEGARDIAN INSIGHTS AND THEORIES AS THE FIRST ATTEMPT TO DESCRIBE THE MODERN HOLISTIC, SEX-BASED MEDICINE. CONCLUSION: HILDEGARD ANTICIPATED A CONCEPT OF PATHOGENESIS THAT SEES A CENTRAL ROLE FOR ENDOCRINOLOGY IN SEX-SPECIFIC DISEASE. FURTHERMORE, ESTROGENS AND ESTROGEN RECEPTORS COULD REPRESENT A GOOD EXAMPLE OF MOLECULAR INTERFACES CAPABLE OF MODULATING THE INTERACTION BETWEEN THE ORGANISM INTERNAL MILIEU AND THE ENVIRONMENTAL FACTORS. 2022 15 3465 32 HYPOTHESIS: REGULATION OF NEUROPLASTICITY MAY INVOLVE I-MOTIF AND G-QUADRUPLEX DNA FORMATION MODULATED BY EPIGENETIC MECHANISMS. RECENT STUDIES DEMONSTRATED THE EXISTENCE IN VIVO OF VARIOUS FUNCTIONAL DNA STRUCTURES THAT DIFFER FROM THE DOUBLE HELIX. THE G-QUADRUPLEX (G4) AND INTERCALATED MOTIF (I-MOTIF OR IM) DNA STRUCTURES ARE FORMED AS KNOTS WHERE, CORRESPONDINGLY, GUANINES OR CYTOSINES ON THE SAME STRAND OF DNA BIND TO EACH OTHER. THERE ARE GROUNDS TO BELIEVE THAT G4 AND IM SEQUENCES PLAY A SIGNIFICANT ROLE IN REGULATING GENE EXPRESSION CONSIDERING THEIR TENDENCY TO BE FOUND IN OR NEAR REGULATORY SITES (SUCH AS PROMOTERS, ENHANCERS, AND TELOMERES) AS WELL AS THE CORRELATION BETWEEN THE PREVALENCE OF G4 OR IM CONFORMATIONS AND SPECIFIC PHASES OF CELL CYCLE. NOTABLY, G4 AND IM CAPABLE SEQUENCES TEND TO BE FOUND ON THE OPPOSITE STRANDS OF THE SAME DNA SITE WITH AT MOST ONE OF THE TWO STRUCTURES FORMED AT ANY GIVEN TIME. THE RECENT EVIDENCE THAT K(+), MG(2+) CONCENTRATIONS DIRECTLY AFFECT IM FORMATION (AND LIKELY G4 FORMATION INDIRECTLY) LEAD US TO BELIEVE THAT THESE STRUCTURES MAY PLAY A MAJOR ROLE IN SYNAPTIC PLASTICITY OF NEURONS, AND, THEREFORE, IN A VARIETY OF CENTRAL NERVOUS SYSTEM (CNS) FUNCTIONS INCLUDING MEMORY, LEARNING, HABITUAL BEHAVIORS, PAIN PERCEPTION AND OTHERS. FURTHERMORE, EPIGENETIC MECHANISMS, WHICH HAVE AN IMPORTANT ROLE IN SYNAPTIC PLASTICITY AND MEMORY FORMATION, WERE ALSO SHOWN TO INFLUENCE FORMATION AND STABILITY OF G4S AND IMS. OUR HYPOTHESIS IS THAT NON-CANONICAL DNA AND RNA STRUCTURES COULD BE AN INTEGRAL PART OF NEUROPLASTICITY CONTROL VIA GENE EXPRESSION REGULATION AT THE LEVEL OF TRANSCRIPTION, TRANSLATION AND SPLICING. WE PROPOSE THAT THE REGULATORY ACTIVITY OF DNA IM AND G4 STRUCTURES IS MODULATED BY DNA METHYLATION/DEMETHYLATION OF THE IM AND/OR G4 SEQUENCES, WHICH FACILITATES THE SWITCH BETWEEN CANONICAL AND NON-CANONICAL CONFORMATION. OTHER NEURONAL MECHANISMS INTERACTING WITH THE FORMATION AND REGULATORY ACTIVITY OF NON-CANONICAL DNA AND RNA STRUCTURES, PARTICULARLY G4, IM AND TRIPLEXES, MAY INVOLVE MICRORNAS AS WELL AS ION AND PROTON FLUXES. WE ARE PROPOSING EXPERIMENTS IN ACUTE BRAIN SLICES AND IN VIVO TO TEST OUR HYPOTHESIS. THE PROPOSED STUDIES WOULD PROVIDE NEW INSIGHTS INTO FUNDAMENTAL NEURONAL MECHANISMS IN HEALTH AND DISEASE AND POTENTIALLY OPEN NEW AVENUES FOR TREATING MENTAL HEALTH DISORDERS. 2019 16 6351 21 THE ROLE OF EPIGENOMICS IN MAPPING POTENTIAL PRECURSORS FOR FOOT AND ANKLE TENDINOPATHY: A SYSTEMATIC REVIEW. TENDINOPATHY OF THE FOOT AND ANKLE IS A COMMON CLINICAL PROBLEM FOR WHICH THE EXACT ETIOLOGY IS POORLY UNDERSTOOD. THE FIELD OF EPIGENETICS HAS BEEN A RECENT FOCUS OF THIS INVESTIGATION. THE PURPOSE OF THIS ARTICLE WAS TO REVIEW THE GENOMIC ADVANCES IN FOOT AND ANKLE TENDINOPATHY THAT COULD POTENTIALLY BE USED TO STRATIFY DISEASE RISK AND CREATE PREVENTATIVE OR THERAPEUTIC AGENTS. A MULTI-DATABASE SEARCH OF PUBMED, COCHRANE, GOOGLE SCHOLAR, AND CLINICALTRIALS.GOV FROM JANUARY 1, 2000 TO JULY 1, 2022 WAS PERFORMED. A TOTAL OF 18 ARTICLES MET INCLUSION AND EXCLUSION CRITERIA FOR THIS REVIEW. THE MAJORITY OF SUCH RESEARCH UTILIZED CASE-CONTROL CANDIDATE GENE ASSOCIATION TO IDENTIFY DIFFERENT GENETIC RISK FACTORS ASSOCIATED WITH CHRONIC TENDINOPATHY. POLYMORPHISMS IN COLLAGEN GENES COL5A1, COL27A1, AND COL1A1 WERE NOTED AT A SIGNIFICANTLY HIGHER FREQUENCY IN ACHILLES TENDINOPATHY VERSUS CONTROL GROUPS. OTHER ALLELIC VARIATIONS THAT WERE OBSERVED AT AN INCREASED INCIDENCE IN ACHILLES TENDINOPATHY WERE TNC AND CASP8. THE EXTRACELLULAR MATRIX (ECM) DEMONSTRATED MACROSCOPIC CHANGES IN ACHILLES TENDINOPATHY, INCLUDING AN INCREASE IN AGGRECAN AND BIGLYCAN MRNA EXPRESSION, AND INCREASED EXPRESSION OF MULTIPLE MATRIX METALLOPROTEINASES. CYTOKINE EXPRESSION WAS ALSO INFLUENCED IN PATHOLOGY AND ABERRANTLY DEMONSTRATED DYNAMIC RESPONSE TO MECHANICAL LOAD. THE PATHOLOGIC ACCUMULATION OF ECM PROTEINS AND CYTOKINE EXPRESSION ALTERS THE ADAPTIVE RESPONSE NORMAL TENDON HAS TO PHYSIOLOGIC STRESS, FURTHER PROPAGATING THE RISK FOR TENDINOPATHY. BY IDENTIFYING AND UNDERSTANDING THE EPIGENETIC MEDIATORS THAT LEAD TO TENDINOPATHY, THERAPEUTIC AGENTS CAN BE DEVELOPED TO TARGET THE EXACT UNDERLYING ETIOLOGY AND MINIMIZE SIDE EFFECTS.LEVEL OF EVIDENCE: LEVEL IV: SYSTEMATIC REVIEW OF LEVEL II-IV STUDIES. 2023 17 6464 25 TISSUE MISREPAIR HYPOTHESIS FOR RADIATION CARCINOGENESIS. DOSE-RESPONSE CURVES FOR CHRONIC LEUKEMIA IN A-BOMB SURVIVORS AND LIVER TUMORS IN PATIENTS GIVEN THOROTRAST (COLLOIDAL THORIUM DIOXIDE) SHOW LARGE THRESHOLD EFFECTS. THE EXISTENCE OF THESE THRESHOLD EFFECTS CAN BE EXPLAINED BY THE FOLLOWING HYPOTHESIS. A HIGH DOSE OF RADIATION CAUSES A PERSISTENT WOUND IN A CELL-RENEWABLE TISSUE. DISORDER OF THE INJURED CELL SOCIETY PARTLY FREES THE COMPONENT CELLS FROM TERRITORIAL RESTRAINTS ON THEIR PROLIFERATION, ENABLING THEM TO CONTINUE DEVELOPMENT OF THEIR CELLULAR FUNCTIONS TOWARD ADVANCED AUTONOMY. THIS PROGRESSION MIGHT BE ACHIEVED BY CONTINUED EPIGENETIC AND GENETIC CHANGES AS A RESULT OF OCCASIONAL ERRORS IN THE OTHERWISE CONCERTED HEALING ACTION OF VARIOUS ENDOGENOUS FACTORS RECRUITED FOR TISSUE REPAIR. CARCINOGENESIS IS NOT SIMPLY A SINGLE-CELL PROBLEM BUT A CELL-SOCIETY PROBLEM. THEREFORE, IT IS NOT WARRANTED TO ESTIMATE RISK AT LOW DOSES BY LINEAR EXTRAPOLATION FROM CANCER DATA AT HIGH DOSES WITHOUT KNOWLEDGE OF THE MECHANISM OF RADIATION CARCINOGENESIS. 1991 18 2533 30 EPIGENETICS IN AUTOIMMUNE CONNECTIVE TISSUE DISEASES. BACKGROUND. AUTOIMMUNE CONNECTIVE TISSUE DISEASES (ACTDS) ENCOMPASS A HETEROGENEOUS GROUP OF CHRONIC IMMUNE-MEDIATED INFLAMMATORY DISORDERS, PRIMARILY AFFECTING CONNECTIVE TISSUES AND CLINICALLY CHARACTERIZED BY VARIABLE MULTISYSTEM MANIFESTATIONS, FREQUENTLY OVERLAPPING. ENVIRONMENTAL FACTORS ARE THOUGHT TO PROMOTE ACTD DEVELOPMENT IN GENETIC PREDISPOSING/ENDOCRINE PERMISSIVE BACKGROUND THROUGH THE INDUCTION OF EPIGENETIC MODIFICATIONS, CONSISTING OF STABLE, HERITABLE, BUT POTENTIALLY REVERSIBLE CHANGES IN GENE EXPRESSION, OCCURRING WITHOUT ALTERATIONS OF THE DNA SEQUENCE. ACTUALLY, EPIGENETIC MECHANISMS (SUCH AS HISTONE MODIFICATIONS, DNA METHYLATION, NUCLEOSOME POSITIONING, AND RNA INTERFERENCE) LINK GENOTYPE UPSTREAM AND PHENOTYPE DOWNSTREAM, AND, IF PERSISTENTLY ABERRANT, MAY CAUSE A VARIETY OF HUMAN DISEASES, INCLUDING ACTDS. WE AIMED TO REVIEW THE RECENT ADVANCES IN THE KNOWLEDGE OF THE ACTD EPIGENETIC ALTERATIONS. METHODS: A DETAILED SEARCH OF THE AVAILABLE LITERATURE WAS PERFORMED IN THE PUBMED (U.S. NATIONAL LIBRARY OF MEDICINE) DATABASE. RESULTS: GROWING EVIDENCE UNDERLINES THE RELEVANT ROLE OF EPIGENETIC DEFECTS IN THE ACTD PATHOGENESIS, AND SPECIFIC EPIGENETIC PATTERNS CAN REPRESENT DISEASE BIOMARKERS. IN PATIENTS WITH RHEUMATOID ARTHRITIS (RA), EPIGENETIC VARIATIONS INTERACT DETERMINING THE TYPICAL "AGGRESSIVE" PHENOTYPE DISPLAYED BY RA SYNOVIAL FIBROBLASTS. EPIGENETIC MODIFICATIONS ARE INVOLVED IN THE PROFIBROTIC PROCESS THAT CHARACTERIZES SYSTEMIC SCLEROSIS. IN SYSTEMIC LUPUS ERYTHEMATOSUS AND SJOGREN'S SYNDROME, COMPLEX EPIGENETIC CHANGES ALTERING GENE EXPRESSION HAVE BEEN DEMONSTRATED. CONCLUSIONS: COMPREHENSIVE STUDIES WILL CONTRIBUTE TO FURTHER DEFINE THE ABERRANT EPIGENETIC MECHANISMS INVOLVED IN THE ACTDS ETIOPATHOGENESIS. MOREOVER, BEING EPIGENETIC CHANGES POTENTIALLY REVERSIBLE, THE IDENTIFICATION OF ACTDS EPIGENETIC BIOMARKERS WILL ALLOW THE DEVELOPMENT OF THERAPEUTIC STRATEGIES ADDRESSED TO TARGET DYSREGULATED GENES AND CORRECT ABERRANT EPIGENOMIC ALTERATIONS. 2014 19 6642 26 UNRAVELING THE PATHOGENESIS OF ASTHMA AND CHRONIC OBSTRUCTIVE PULMONARY DISEASE OVERLAP: FOCUSING ON EPIGENETIC MECHANISMS. ASTHMA AND COPD OVERLAP (ACO) IS CHARACTERIZED BY PATIENTS PRESENTING WITH PERSISTENT AIRFLOW LIMITATION AND FEATURES OF BOTH ASTHMA AND COPD. IT IS ASSOCIATED WITH A HIGHER FREQUENCY AND SEVERITY OF EXACERBATIONS, A FASTER LUNG FUNCTION DECLINE, AND A HIGHER HEALTHCARE COST. SYSTEMIC INFLAMMATION IN COPD AND ASTHMA IS DRIVEN BY TYPE 1 T HELPER (TH1) AND TH2 IMMUNE RESPONSES, RESPECTIVELY, BOTH OF WHICH MAY CONTRIBUTE TO AIRWAY REMODELING IN ACO. ACO-RELATED BIOMARKERS CAN BE CLASSIFIED INTO FOUR CATEGORIES: NEUTROPHIL-MEDIATED INFLAMMATION, TH2 CELL RESPONSES, ARACHIDONIC ACID-EICOSANOIDS PATHWAY, AND METABOLITES. GENE-ENVIRONMENT INTERACTIONS ARE KEY CONTRIBUTORS TO THE COMPLEXITY OF ACO AND ARE REGULATED BY EPIGENETIC MECHANISMS, INCLUDING DNA METHYLATION, HISTONE MODIFICATIONS, AND NON-CODING RNAS. THUS, THIS REVIEW FOCUSES ON THE LINK BETWEEN EPIGENETICS AND ACO, AND OUTLINES THE FOLLOWING: (I) INHERITING EPIGENOTYPES WITHOUT CHANGE WITH ENVIRONMENTAL STIMULI, OR EPIGENETIC CHANGES IN RESPONSE TO LONG-TERM EXPOSURE TO INHALED PARTICLES PLUS INTERMITTENT EXPOSURE TO SPECIFIC ALLERGENS; (II) EPIGENETIC MARKERS DISTINGUISHING ACO FROM COPD AND ASTHMA; (III) POTENTIAL EPIGENETIC DRUGS THAT CAN REVERSE OXIDATIVE STRESS, GLUCOCORTICOID INSENSITIVITY, AND CELL INJURY. IMPROVED UNDERSTANDING OF THE EPIGENETIC REGULATIONS HOLDS GREAT VALUE TO GIVE DEEPER INSIGHT INTO THE MECHANISMS, AND CLARIFY THEIR IMPLICATIONS FOR BIOMEDICAL RESEARCH IN ACO. 2022 20 1728 25 DYSREGULATION OF MICRORNAS IN HYPERTROPHY AND OSSIFICATION OF LIGAMENTUM FLAVUM: NEW ADVANCES, CHALLENGES, AND POTENTIAL DIRECTIONS. PATHOLOGICAL CHANGES IN THE LIGAMENTUM FLAVUM (LF) CAN BE DEFINED AS A PROCESS OF CHRONIC PROGRESSIVE ABERRATIONS IN THE NATURE AND STRUCTURE OF LIGAMENTOUS TISSUES CHARACTERIZED BY INCREASED THICKNESS, REDUCED ELASTICITY, LOCAL CALCIFICATION, OR AGGRAVATED OSSIFICATION, WHICH MAY CAUSE SEVERE MYELOPATHY, RADICULOPATHY, OR BOTH. HYPERTROPHY OF LIGAMENTUM FLAVUM (HLF) AND OSSIFICATION OF LIGAMENTUM FLAVUM (OLF) ARE CLINICALLY COMMON ENTITIES. THOUGH ACCUMULATED EVIDENCE HAS INDICATED BOTH GENETIC AND ENVIRONMENTAL FACTORS COULD CONTRIBUTE TO THE INITIATION AND PROGRESSION OF HLF/OLF, THE DEFINITE PATHOGENESIS REMAINS FULLY UNCLEAR. MICRORNAS (MIRNAS), ONE OF THE IMPORTANT EPIGENETIC MODIFICATIONS, ARE SHORT SINGLE-STRANDED RNA MOLECULES THAT REGULATE PROTEIN-CODING GENE EXPRESSION AT POSTTRANSCRIPTIONAL LEVEL, WHICH CAN DISCLOSE THE MECHANISM UNDERLYING DISEASES, IDENTIFY VALUABLE BIOMARKERS, AND EXPLORE POTENTIAL THERAPEUTIC TARGETS. CONSIDERING THAT MIRNAS PLAY A CENTRAL ROLE IN REGULATING GENE EXPRESSION, WE SUMMARIZED CURRENT STUDIES FROM THE POINT OF VIEW OF MIRNA-RELATED MOLECULAR REGULATION NETWORKS IN HLF/OLF. EXPLORATORY STUDIES REVEALED A VARIETY OF MIRNA EXPRESSION PROFILES AND IDENTIFIED A BATTERY OF UPREGULATED AND DOWNREGULATED MIRNAS IN OLF/HLF PATIENTS THROUGH MICROARRAY DATASETS OR TRANSCRIPTOME SEQUENCING. EXPERIMENTAL STUDIES VALIDATED THE ROLES OF SPECIFIC MIRNAS (E.G., MIR-132-3P, MIR-199B-5P IN OLF, MIR-155, AND MIR-21 IN HLF) IN REGULATING FIBROSIS OR OSTEOGENESIS DIFFERENTIATION OF LF CELLS AND RELATED TARGET GENES OR MOLECULAR SIGNALING PATHWAYS. FINALLY, WE DISCUSSED THE PERSPECTIVES AND CHALLENGES OF MIRNA-BASED MOLECULAR MECHANISM, DIAGNOSTIC BIOMARKERS, AND THERAPEUTIC TARGETS OF HLF/OLF. 2021