1 4756 172 NOVEL THERAPEUTIC TARGET(S) FOR PSORIATIC DISEASE. PSORIASIS AND PSORIATIC ARTHRITIS, TOGETHER KNOWN AS PSORIATIC DISEASE, IS HIGHLY PREVALENT CHRONIC RELAPSING INFLAMMATORY DISEASE AFFECTING SKIN, JOINTS OR BOTH AND IS ASSOCIATED WITH SEVERAL COMORBIDITIES SUCH AS CARDIOVASCULAR, METABOLIC, PSYCHIATRIC, RENAL DISEASE ETC. THE ETIOPATHOGENESIS OF PSORIASIS IS COMPLEX AND MAINLY DRIVEN BY ABERRANT IMMUNE RESPONSE OWING TO THE GENETIC SUSCEPTIBILITY AND VARIOUS ENVIRONMENTAL FACTORS SUCH AS TRAUMA, INFECTIONS AND DRUGS. RECENT ADVANCES IN UNDERSTANDING MOLECULAR AND CELLULAR PATHWAYS HAVE IDENTIFIED TUMOR NECROSIS FACTOR-ALPHA (TNF-ALPHA), INTERLEUKIN-17 (IL-17), IL-23, IL-22 AS MAJOR CONTRIBUTORS IN PSORIASIS PATHOGENESIS. ADVANCES IN THE KNOWLEDGE OF PATHOPHYSIOLOGY, THE INTERACTION OF AUTOINFLAMMATION AND CLINICAL PHENOTYPES HAVE LED TO THE DEVELOPMENT OF HIGHLY EFFECTIVE TARGETED THERAPEUTIC AGENTS WHICH INCLUDE TNF-ALPHA, IL-17, IL-23, IL-1 ALPHA/BETA OR IL-36 INHIBITORS OR RECEPTOR BLOCKERS, SMALL MOLECULE DRUGS LIKE PHOSPHODIESTERASE-4 INHIBITORS (APREMILAST), JANUS KINASE (JAK) INHIBITORS, RETINOIC ACID RECEPTOR-RELATED ORPHAN RECEPTOR GAMMAT (RORGAMMAT) INHIBITORS. THESE NOVEL DRUGS HAVE PROMISED THE POTENTIAL OF IMPROVED DISEASE CONTROL. IN RECENT YEARS, THE TRANSITION FROM BIOLOGICS TO BIOSIMILARS ESPECIALLY WITH TNF-ALPHA INHIBITORS HAD SIGNIFICANT IMPACT ON DECREASING HEALTH CARE COST AND INCREASING THERAPEUTIC OPTIONS TO THE PATIENTS. HOWEVER, SELECTION OF RIGHT TREATMENT FOR AN INDIVIDUAL PATIENT STILL REMAINS CHALLENGING. MOREOVER, INTERPLAY BETWEEN DIFFERENT EPIGENETIC MECHANISMS SUCH AS THE DNA METHYLATION, CHROMATIN MODIFICATIONS AND NONCODING RNA REGULATION HAS RECENTLY BEEN STARTED TO BE DECIPHERED. ENZYMES INHIBITORS INVOLVED IN EPIGENETIC PATHWAYS SUCH AS DNA METHYLTRANSFERASES AND HISTONE DEACETYLASES DEMONSTRATED TO RESTORE NORMAL EPIGENETIC PATTERNS IN CLINICAL SETTINGS AND HAVE PROVIDED THE POTENTIAL AS NOVEL THERAPEUTIC TARGETS FOR PSORIASIS. IN THIS REVIEW, WE WILL DISCUSS NOVEL BIOLOGIC AGENTS AND NEWER THERAPEUTIC APPROACHES IN TREATMENT OF PSORIATIC DISEASE. 2022 2 2726 49 EXPERIMENTAL PHARMACOLOGICAL MANAGEMENT OF PSORIASIS. PSORIASIS IS A CHRONIC, RELAPSING, IMMUNE-MEDIATED SYSTEMIC DISEASE. ITS PATHOGENESIS IS COMPLEX AND NOT FULLY UNDERSTOOD YET. GENETIC AND EPIGENETIC FACTORS INTERACT WITH MOLECULAR PATHWAYS INVOLVING TNF-ALPHA, IL-23/IL-17 AXIS, AND PECULIAR CYTOKINES, AS IL-36 OR PHOSPHODIESTERASE 4. THIS REVIEW DISCUSSES THE MECHANISMS INVOLVED IN THE DEVELOPMENT OF THE DISEASE, AS WELL AS THE THERAPEUTIC OPTIONS PROPOSED FOLLOWING THE INVESTIGATION OF THE INFLAMMATORY PSORIATIC PATHWAYS. WE PERFORMED A COMPREHENSIVE SEARCH USING THE WORDS "PSORIASIS" AND THE NEWEST MOLECULES CURRENTLY UNDER INVESTIGATION AND APPROVAL. FROM THESE DATA, A NEW SCENARIO IN PSORIASIS IS OCCURRING TO PERSONALIZE THE THERAPIES - ESPECIALLY SYSTEMIC ONES AND THOSE USING SMALL MOLECULES - AND AVOID TOPICAL AND INJECTABLE DRUGS. WE REPORTED THE NEWEST THERAPEUTIC OPPORTUNITIES, INCLUDING THE INHIBITORS OF JANUS KINASE/TYROSINE KINASE 2, PHOSPHODIESTERASE-4 AND IL-36 RECEPTOR. TODAY, MORE THAN 20 MOLECULES ARE UNDER INVESTIGATION FOR THE TREATMENT OF CUTANEOUS PSORIASIS. MOST OF THEM ARE CONSTITUTED BY SMALL MOLECULES OR BIOLOGIC THERAPIES. THIS UNDERLINES HOW PSORIASIS NEEDS SYSTEMIC THERAPIES, DUE TO ITS COMPLEX PATHOGENESIS AND MULTISYSTEMIC INVOLVEMENT. 2021 3 6202 63 THE INFLAMMATORY RESPONSE IN PSORIASIS: A COMPREHENSIVE REVIEW. PSORIASIS IS A CHRONIC INFLAMMATORY AUTOIMMUNE DISEASE CHARACTERIZED BY AN EXCESSIVELY ABERRANT HYPERPROLIFERATION OF KERATINOCYTES. THE PATHOGENESIS OF PSORIASIS IS COMPLEX AND THE EXACT MECHANISM REMAINS ELUSIVE. HOWEVER, PSORIASIS IS THOUGHT TO RESULT FROM A COMBINATION OF GENETIC, EPIGENETIC, AND ENVIRONMENTAL INFLUENCES. RECENT STUDIES HAVE IDENTIFIED THAT EPIGENETIC FACTORS INCLUDING DYSREGULATED DNA METHYLATION LEVELS, ABNORMAL HISTONE MODIFICATION AND MICRORNAS EXPRESSIONS ARE INVOLVED IN THE DEVELOPMENT OF PSORIASIS. THE INTERPLAY OF IMMUNE CELLS AND CYTOKINES IS ANOTHER CRITICAL FACTOR IN THE PATHOGENESIS OF PSORIASIS. THESE FACTORS OR PATHWAYS INCLUDE TH1/TH2 HOMEOSTASIS, THE TH17/TREG BALANCE AND THE IL-23/TH17 AXIS. TH17 IS BELIEVED PARTICULARLY IMPORTANT IN PSORIASIS DUE TO ITS PRO-INFLAMMATORY EFFECTS AND ITS INVOLVEMENT IN AN INTEGRATED INFLAMMATORY LOOP WITH DENDRITIC CELLS AND KERATINOCYTES, CONTRIBUTING TO AN OVERPRODUCTION OF ANTIMICROBIAL PEPTIDES, INFLAMMATORY CYTOKINES, AND CHEMOKINES THAT LEADS TO AMPLIFICATION OF THE IMMUNE RESPONSE. IN ADDITION, OTHER PATHWAYS AND SIGNALING MOLECULES HAVE BEEN FOUND TO BE INVOLVED, INCLUDING TH9, TH22, REGULATORY T CELLS, GAMMADELTA T CELLS, CD8(+) T CELLS, AND THEIR RELATED CYTOKINES. UNDERSTANDING THE PATHOGENESIS OF PSORIASIS WILL ALLOW US TO DEVELOP INCREASINGLY EFFICIENT TARGETED TREATMENT BY BLOCKING RELEVANT INFLAMMATORY SIGNALING PATHWAYS AND MOLECULES. THERE IS NO CURE FOR PSORIASIS AT THE PRESENT TIME, AND MUCH OF THE TREATMENT INVOLVES MANAGING THE SYMPTOMS. THE BIOLOGICS, WHILE LACKING THE ADVERSE EFFECTS ASSOCIATED WITH SOME OF THE TRADITIONAL MEDICATIONS SUCH AS CORTICOSTEROIDS AND METHOTREXATE, HAVE THEIR OWN SET OF SIDE EFFECTS, WHICH MAY INCLUDE REACTIVATION OF LATENT INFECTIONS. SIGNIFICANT CHALLENGES REMAIN IN DEVELOPING SAFE AND EFFICACIOUS NOVEL TARGETED THERAPIES THAT DEPEND ON A BETTER UNDERSTANDING OF THE IMMUNOLOGICAL DYSFUNCTION IN PSORIASIS. 2016 4 2591 67 EPIGENETICS OF PSORIASIS. PSORIASIS IS A CHRONIC AND RECURRENT INFLAMMATORY SKIN DISEASE, INVOLVING THE RAPID PROLIFERATION AND ABNORMAL DIFFERENTIATION OF KERATINOCYTES AND ACTIVATION OF T CELLS. IT IS GENERALLY ACCEPTED THAT THE CENTRAL PATHOGENESIS OF PSORIASIS IS A T CELL-DOMINANT IMMUNE DISORDER AFFECTED BY MULTIPLE FACTORS INCLUDING GENETIC SUSCEPTIBILITY, ENVIRONMENTAL FACTORS, INNATE AND ADAPTIVE IMMUNE RESPONSES, ETC. HOWEVER, THE EXACT ETIOLOGY IS LARGELY UNKNOWN. IN RECENT YEARS, EPIGENETIC INVOLVEMENTS, SUCH AS THE DNA METHYLATION, CHROMATIN MODIFICATIONS, AND NONCODING RNA REGULATION ARE REPORTED TO BE CRITICAL FOR THE PATHOGENESIS OF PSORIASIS. HOWEVER, THE INTERPLAY BETWEEN THESE FACTORS HAS ONLY RECENTLY BEEN STARTED TO BE UNRAVELED. NOTABLY, INHIBITORS OF ENZYMES THAT WORK IN EPIGENETIC MODIFICATIONS, SUCH AS DNA METHYLTRANSFERASES AND HISTONE DEACETYLASES, ARE BEGINNING TO APPEAR IN THE CLINICAL SETTING TO RESTORE NORMAL EPIGENETIC PATTERNS (GENERALI ET AL. IN J AUTOIMMUN 83:51-61, 2017), PROVIDING NOVEL THERAPEUTIC POTENTIAL AS NOVEL TREATMENT TARGETS FOR PSORIASIS. INDEED, MEDICATIONS PREVIOUSLY USED TO TREAT AUTOIMMUNE DISEASES HAVE LATER BEEN DISCOVERED TO EXERT THEIR ACTION VIA EPIGENETIC MECHANISMS. HEREIN, WE REVIEW THE FINDINGS ON EPIGENETICS ASSOCIATED WITH PSORIASIS, AND DISCUSS FUTURE PERSPECTIVES IN THIS FIELD. 2020 5 6114 61 THE EPIGENETIC CONTRIBUTION TO THE PATHOGENESIS OF PSORIASIS: RECENT ADVANCES. PSORIASIS IS DEFINED AS A CHRONIC AUTOIMMUNE DISORDER OF THE SKIN IN WHICH ABNORMAL PROLIFERATION AND DIFFERENTIATION OF KERATINOCYTES ARE BLAMED AS THE CENTRAL CULPRIT OF DISEASE ETIOPATHOGENESIS. A COMPLEX INTERPLAY BETWEEN ENVIRONMENTAL FACTORS AND GENETIC RISK FACTORS HAS BEEN SUGGESTED TO TRIGGER THE DISEASE. HOWEVER, EPIGENETIC REGULATION APPEARS TO CONNECT EXTERNAL STIMULI AND GENETIC ABNORMALITIES IN THE DEVELOPMENT OF PSORIASIS. THE DISCORDANCE IN THE PREVALENCE OF PSORIASIS BETWEEN MONOZYGOTIC TWINS AND ENVIRONMENTAL FACTORS THAT CONTRIBUTE TO ITS ONSET HAVE CAUSED A PARADIGM SHIFT REGARDING THE MECHANISMS UNDERLYING THE PATHOGENESIS OF THIS DISEASE. EPIGENETIC DYSREGULATION MAY BE INVOLVED IN ABERRANCIES OF KERATINOCYTE DIFFERENTIATION, T-CELL ACTIVATION, AND OTHER PLAUSIBLE CELLS, LEADING TO THE INITIATION AND PERPETUATION OF PSORIASIS. EPIGENETICS IS CHARACTERIZED BY HERITABLE ALTERATIONS IN THE TRANSCRIPTION OF GENES WITHOUT NUCLEOTIDE CHANGE AND IS COMMONLY CONSIDERED AT THREE LEVELS, I.E., DNA METHYLATION, HISTONE MODIFICATIONS, AND MICRORNAS. TO DATE, SCIENTIFIC EVIDENCE HAS INDICATED ABNORMAL DNA METHYLATION, HISTONE MODIFICATIONS, AND NON-CODING RNA TRANSCRIPTION IN PSORIATIC PATIENTS. IN ORDER TO REVERSE ABERRANT EPIGENETIC CHANGES IN PSORIASIS PATIENTS, SEVERAL COMPOUNDS AND DRUGS (EPI-DRUGS) HAVE BEEN DEVELOPED TO AFFECT THE MAJOR ENZYMES INVOLVED IN THE METHYLATION OF DNA, OR THE ACETYLATION OF HISTONES, WHICH AIM TO CORRECT THE ABERRANT METHYLATION AND ACETYLATION PATTERNS. A NUMBER OF CLINICAL TRIALS HAVE SUGGESTED THE THERAPEUTIC POTENTIAL OF SUCH DRUGS IN THE TREATMENT OF PSORIASIS. IN THE PRESENT REVIEW, WE ATTEMPT TO CLARIFY RECENT FINDINGS WITH RESPECT TO EPIGENETIC IRREGULARITIES IN PSORIASIS AND DISCUSS FUTURE CHALLENGES. 2023 6 5421 34 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 7 2578 53 EPIGENETICS OF INFLAMMATORY BOWEL DISEASES. INFLAMMATORY BOWEL DISEASES ARE MULTIFACTORIAL, CHRONIC, CONTINUOUS, RELAPSING, AND IMMUNE-MEDIATED DISEASES OF THE GASTROINTESTINAL TRACT. IT HAS BEEN BELIEVED THAT MECHANISMS UNDERLYING INFLAMMATORY BOWEL DISEASES INCLUDE GENETIC PREDISPOSITION, ENVIRONMENTAL FACTORS, AND ALTERED IMMUNE RESPONSE TO THE GUT MICROBIOME. THE EPIGENETIC MODULATION TAKES PLACE VIA CHROMATIN MODIFICATIONS, INCLUDING PHOSPHORYLATION, ACETYLATION, METHYLATION, SUMOYLATION, AND UBIQUITINATION. THE METHYLATION LEVELS OF COLONIC TISSUE WERE FOUND WELL CORRELATED TO BLOOD SAMPLES IN INFLAMMATORY BOWEL DISEASES. MOREOVER, THE METHYLATION LEVEL OF SPECIFIC GENES WAS DIFFERENT BETWEEN CROHN'S DISEASE AND ULCERATIVE COLITIS. IT HAS BEEN SHOWN THAT THE ENZYMES AFFECTING HISTONE MODIFICATIONS LIKE HISTONE DEACETYLASES AND HISTONE ACETYLTRANSFERASES DO NOT ACT SOLELY ON HISTONES BUT ALSO AFFECT THE ACETYLATION OF MANY PROTEINS SUCH AS P53 AND STAT3. IT HAS BEEN ALREADY SHOWN THAT A NONSELECTIVE HISTONE DEACETYLASE INHIBITOR, VORINOSTAT (SAHA), WHICH IS CURRENTLY BEING USED IN SEVERAL CANCER TREATMENTS, SHOWED ANTI-INFLAMMATORY ACTIVITIES IN MOUSE MODELS. AMONG EPIGENETIC ALTERATIONS, LONG NON-CODING RNAS AND MICRORNAS PLAY SIGNIFICANT ROLES IN T-CELL MATURATION, DIFFERENTIATION, ACTIVATION, AND SENILITY. THE LONG NON-CODING RNA AND MICRORNA EXPRESSION PROFILES CAN PERFECTLY SEPARATE INFLAMMATORY BOWEL DISEASE PATIENTS FROM HEALTHY CONTROLS AND ARE REMARKED AS BIOMARKERS OF INFLAMMATORY BOWEL DISEASES. OVERALL, MANY STUDIES HAVE SHOWN THAT EPIGENETIC INHIBITORS CAN TARGET SIGNIFICANT SIGNAL PATHWAYS IN THE PATHOGENESIS OF INFLAMMATORY BOWEL DISEASES, AND THE IMPACT OF EPIGENETIC INHIBITORS IS BEING STUDIED IN CLINICAL TRIALS. IN CONCLUSION, EXPLORING MORE EPIGENETIC PATHWAYS REGARDING INFLAMMATORY BOWEL DISEASE PATHOGENESIS WILL HELP US TO DISCOVER THERAPEUTIC TARGETS AND NEW DRUGS AND AGENTS TARGETING MIRNAS IN INFLAMMATORY BOWEL DISEASES. IN GENERAL, DISCOVERING EPIGENETIC TARGETS COULD IMPROVE THE DIAGNOSIS AND TREATMENT OF INFLAMMATORY BOWEL DISEASES. 2023 8 1172 42 CONTRIBUTION OF THE ENVIRONMENT, EPIGENETIC MECHANISMS AND NON-CODING RNAS IN PSORIASIS. DESPITE THE INCREASING RESEARCH AND CLINICAL INTEREST IN THE PREDISPOSITION OF PSORIASIS, A CHRONIC INFLAMMATORY SKIN DISEASE, THE MULTITUDE OF GENETIC AND ENVIRONMENTAL FACTORS INVOLVED IN ITS PATHOGENESIS REMAIN UNCLEAR. THIS COMPLEXITY IS FURTHER EXACERBATED BY THE SEVERAL CELL TYPES THAT ARE IMPLICATED IN PSORIASIS'S PROGRESSION, INCLUDING KERATINOCYTES, MELANOCYTES AND VARIOUS IMMUNE CELL TYPES. THE OBSERVED INTERACTIONS BETWEEN THE GENETIC SUBSTRATE AND THE ENVIRONMENT LEAD TO EPIGENETIC ALTERATIONS THAT DIRECTLY OR INDIRECTLY AFFECT GENE EXPRESSION. CHANGES IN DNA METHYLATION AND HISTONE MODIFICATIONS THAT ALTER DNA-BINDING SITE ACCESSIBILITY, AS WELL AS NON-CODING RNAS IMPLICATED IN THE POST-TRANSCRIPTIONAL REGULATION, ARE MECHANISMS OF GENE TRANSCRIPTIONAL ACTIVITY MODIFICATION AND THEREFORE AFFECT THE PATHWAYS INVOLVED IN THE PATHOGENESIS OF PSORIASIS. IN THIS REVIEW, WE SUMMARIZE THE RESEARCH CONDUCTED ON THE ENVIRONMENTAL FACTORS CONTRIBUTING TO THE DISEASE ONSET, EPIGENETIC MODIFICATIONS AND NON-CODING RNAS EXHIBITING DEREGULATION IN PSORIASIS, AND WE FURTHER CATEGORIZE THEM BASED ON THE UNDER-STUDY CELL TYPES. WE ALSO ASSESS THE RECENT LITERATURE CONSIDERING THERAPEUTIC APPLICATIONS TARGETING MOLECULES THAT COMPROMISE THE EPIGENOME, AS A WAY TO SUPPRESS THE INFLAMMATORY CUTANEOUS CASCADE. 2022 9 4883 49 OVERVIEW OF THE MOLECULAR DETERMINANTS CONTRIBUTING TO THE EXPRESSION OF PSORIASIS AND PSORIATIC ARTHRITIS PHENOTYPES. PSORIASIS AND PSORIATIC ARTHRITIS ARE MULTIFACTORIAL CHRONIC DISORDERS WHOSE ETIOPATHOGENESIS ESSENTIALLY DERIVES FROM THE ALTERATION OF SEVERAL SIGNALLING PATHWAYS AND THE CO-OCCURRENCE OF GENETIC, EPIGENETIC AND NON-GENETIC SUSCEPTIBILITY FACTORS THAT ALTOGETHER AFFECT THE FUNCTIONAL AND STRUCTURAL PROPERTY OF THE SKIN. ALTHOUGH SHARED AND DIFFERENTIAL SUSCEPTIBILITY GENES AND MOLECULAR PATHWAYS ARE KNOWN TO CONTRIBUTE TO THE ONSET OF PATHOLOGICAL PHENOTYPES, FURTHER RESEARCH IS NEEDED TO DISSECT THE MOLECULAR CAUSES OF PSORIATIC DISEASE AND ITS PROGRESSION TOWARDS PSORIATIC ARTHRITIS. THIS REVIEW WILL THEREFORE BE ADDRESSED TO EXPLORE DIFFERENCES AND SIMILARITIES IN THE ETIOPATHOGENESIS AND PROGRESSION OF BOTH DISORDERS, WITH A PARTICULAR FOCUS ON GENES INVOLVED IN THE MAINTENANCE OF THE SKIN STRUCTURE AND INTEGRITY (KERATINS AND COLLAGENS), MODULATION OF PATTERNS OF RECOGNITION (THROUGH TOLL-LIKE RECEPTORS AND DECTIN-1) AND IMMUNO-INFLAMMATORY RESPONSE (BY NLRP3-DEPENDENT INFLAMMASOME) TO MICROBIAL PATHOGENS. IN ADDITION, SPECIAL EMPHASIS WILL BE GIVEN TO THE CONTRIBUTION OF EPIGENETIC ELEMENTS (METHYLATION PATTERN, NON-CODING RNAS, CHROMATIN MODIFIERS AND 3D GENOME ORGANIZATION) TO THE ETIOPATHOGENESIS AND PROGRESSION OF PSORIASIS AND PSORIATIC ARTHRITIS. THE EVIDENCE DISCUSSED IN THIS REVIEW HIGHLIGHTS HOW THE KNOWLEDGE OF PATIENTS' CLINICAL AND (EPI)GENOMIC MAKE-UP COULD BE HELPFUL FOR IMPROVING THE AVAILABLE THERAPEUTIC STRATEGIES FOR PSORIASIS AND PSORIATIC ARTHRITIS TREATMENT. 2020 10 5309 43 PSORIASIS PATHOGENESIS AND TREATMENT. RESEARCH ON PSORIASIS PATHOGENESIS HAS LARGELY INCREASED KNOWLEDGE ON SKIN BIOLOGY IN GENERAL. IN THE PAST 15 YEARS, BREAKTHROUGHS IN THE UNDERSTANDING OF THE PATHOGENESIS OF PSORIASIS HAVE BEEN TRANSLATED INTO TARGETED AND HIGHLY EFFECTIVE THERAPIES PROVIDING FUNDAMENTAL INSIGHTS INTO THE PATHOGENESIS OF CHRONIC INFLAMMATORY DISEASES WITH A DOMINANT IL-23/TH17 AXIS. THIS REVIEW DISCUSSES THE MECHANISMS INVOLVED IN THE INITIATION AND DEVELOPMENT OF THE DISEASE, AS WELL AS THE THERAPEUTIC OPTIONS THAT HAVE ARISEN FROM THE DISSECTION OF THE INFLAMMATORY PSORIATIC PATHWAYS. OUR DISCUSSION BEGINS BY ADDRESSING THE INFLAMMATORY PATHWAYS AND KEY CELL TYPES INITIATING AND PERPETUATING PSORIATIC INFLAMMATION. NEXT, WE DESCRIBE THE ROLE OF GENETICS, ASSOCIATED EPIGENETIC MECHANISMS, AND THE INTERACTION OF THE SKIN FLORA IN THE PATHOPHYSIOLOGY OF PSORIASIS. FINALLY, WE INCLUDE A COMPREHENSIVE REVIEW OF WELL-ESTABLISHED WIDELY AVAILABLE THERAPIES AND NOVEL TARGETED DRUGS. 2019 11 6597 47 TUNING MONOCYTES AND MACROPHAGES FOR PERSONALIZED THERAPY AND DIAGNOSTIC CHALLENGE IN RHEUMATOID ARTHRITIS. MONOCYTES/MACROPHAGES PLAY A CENTRAL ROLE IN CHRONIC INFLAMMATORY DISORDERS, INCLUDING RHEUMATOID ARTHRITIS (RA). ACTIVATION OF THESE CELLS RESULTS IN THE PRODUCTION OF VARIOUS MEDIATORS RESPONSIBLE FOR INFLAMMATION AND RA PATHOGENESIS. ON THE OTHER HAND, THE DEPLETION OF MACROPHAGES USING SPECIFIC ANTIBODIES OR CHEMICAL AGENTS CAN PREVENT THEIR SYNOVIAL TISSUE INFILTRATION AND SUBSEQUENTLY ATTENUATES INFLAMMATION. THEIR PLASTICITY IS A MAJOR FEATURE THAT HELPS THE SWITCH FROM A PRO-INFLAMMATORY PHENOTYPE (M1) TO AN ANTI-INFLAMMATORY STATE (M2). THEREFORE, UNDERSTANDING THE PRECISE STRATEGY TARGETING PRO-INFLAMMATORY MONOCYTES/MACROPHAGES SHOULD BE A POWERFUL WAY OF INHIBITING CHRONIC INFLAMMATION AND BONE EROSION. IN THIS REVIEW, WE DEMONSTRATE POTENTIAL CONSEQUENCES OF DIFFERENT EPIGENETIC REGULATIONS ON INFLAMMATORY CYTOKINES PRODUCTION BY MONOCYTES. IN ADDITION, WE PRESENT UNIQUE PROFILES OF MONOCYTES/MACROPHAGES CONTRIBUTING TO IDENTIFICATION OF NEW BIOMARKERS OF DISEASE ACTIVITY OR PREDICTING TREATMENT RESPONSE IN RA. WE ALSO OUTLINE NOVEL APPROACHES OF TUNING MONOCYTES/MACROPHAGES BY BIOLOGIC DRUGS, SMALL MOLECULES OR BY OTHER THERAPEUTIC MODALITIES TO REDUCE ARTHRITIS. FINALLY, THE IMPORTANCE OF CELLULAR HETEROGENEITY OF MONOCYTES/MACROPHAGES IS HIGHLIGHTED BY SINGLE-CELL TECHNOLOGIES, WHICH LEADS TO THE DESIGN OF CELL-SPECIFIC THERAPEUTIC PROTOCOLS FOR PERSONALIZED MEDICINE IN RA IN THE FUTURE. 2021 12 3038 45 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 13 4679 44 NEW MOLECULAR TARGETS FOR THE TREATMENT OF OSTEOARTHRITIS. OSTEOARTHRITIS (OA) IS A CHRONIC DEGENERATIVE JOINT DISORDER CHARACTERIZED BY DESTRUCTION OF THE ARTICULAR CARTILAGE, SUBCHONDRAL BONE ALTERATIONS AND SYNOVITIS. CURRENT TREATMENTS ARE FOCUSED ON SYMPTOMATIC RELIEF BUT THEY LACK EFFICACY TO CONTROL THE PROGRESSION OF THIS DISEASE WHICH IS A LEADING CAUSE OF DISABILITY. THEREFORE, THE DEVELOPMENT OF EFFECTIVE DISEASE-MODIFYING DRUGS IS URGENTLY NEEDED. DIFFERENT INITIATIVES ARE IN PROGRESS TO DEFINE THE MOLECULAR MECHANISMS INVOLVED IN THE INITIATION AND PROGRESSION OF OA. THESE STUDIES SUPPORT THE THERAPEUTIC POTENTIAL OF PATHWAYS RELEVANT IN JOINT METABOLISM SUCH AS WNT/BETA-CATENIN, DISCOIDIN DOMAIN RECEPTOR 2 OR PROTEINASE-ACTIVATED RECEPTOR 2. THE DYSREGULATION IN CARTILAGE CATABOLISM AND SUBCHONDRAL BONE REMODELING COULD BE IMPROVED BY SELECTIVE INHIBITORS OF MATRIX METALLOPROTEINASES, AGGRECANASES AND OTHER PROTEASES. ANOTHER APPROACH WOULD FAVOR THE ACTIVITY OF ANABOLIC PROCESSES BY USING GROWTH FACTORS OR REGULATORY MOLECULES. RECENT STUDIES HAVE ALSO REVEALED THE ROLE OF OXIDATIVE STRESS AND SYNOVITIS IN THE PROGRESSION OF THIS DISEASE, SUPPORTING THE DEVELOPMENT OF A NUMBER OF INHIBITORY STRATEGIES. NOVEL TARGETS IN OA ARE REPRESENTED BY GENES INVOLVED IN OA PATHOPHYSIOLOGY DISCOVERED USING GENE NETWORK, EPIGENETIC AND MICRORNA APPROACHES. FURTHER INSIGHTS INTO THE MOLECULAR MECHANISMS INVOLVED IN OA INITIATION AND PROGRESSION MAY LEAD TO THE DEVELOPMENT OF NEW THERAPIES ABLE TO CONTROL JOINT DESTRUCTION AND REPAIR. 2010 14 6340 38 THE ROLE OF EPIGENETIC FACTORS IN PSORIASIS. PSORIASIS IS A CHRONIC, SYSTEMIC, IMMUNE-MEDIATED DISEASE WITH AN INCIDENCE OF APPROXIMATELY 2%. THE PATHOGENESIS OF THE DISEASE IS COMPLEX AND NOT YET FULLY UNDERSTOOD. GENETIC FACTORS PLAY A SIGNIFICANT ROLE IN THE PATHOGENESIS OF THE DISEASE. IN PREDISPOSED INDIVIDUALS, MULTIPLE TRIGGER FACTORS MAY CONTRIBUTE TO DISEASE ONSET AND EXACERBATIONS OF SYMPTOMS. ENVIRONMENTAL FACTORS (STRESS, INFECTIONS, CERTAIN MEDICATIONS, NICOTINISM, ALCOHOL, OBESITY) PLAY A SIGNIFICANT ROLE IN THE PATHOGENESIS OF PSORIASIS. IN ADDITION, EPIGENETIC MECHANISMS ARE CONSIDERED RESULT IN MODULATION OF INDIVIDUAL GENE EXPRESSION AND AN INCREASED LIKELIHOOD OF THE DISEASE. STUDIES HIGHLIGHT THE SIGNIFICANT ROLE OF EPIGENETIC FACTORS IN THE ETIOLOGY AND PATHOGENESIS OF PSORIASIS. EPIGENETIC MECHANISMS IN PSORIASIS INCLUDE DNA METHYLATION, HISTONE MODIFICATIONS AND NON-CODING RNAS. EPIGENETIC MECHANISMS INDUCE GENE EXPRESSION CHANGES UNDER THE INFLUENCE OF CHEMICAL MODIFICATIONS OF DNA AND HISTONES, WHICH ALTER CHROMATIN STRUCTURE AND ACTIVATE TRANSCRIPTION FACTORS OF SELECTED GENES, THUS LEADING TO TRANSLATION OF NEW MRNA WITHOUT AFFECTING THE DNA SEQUENCE. EPIGENETIC FACTORS CAN REGULATE GENE EXPRESSION AT THE TRANSCRIPTIONAL (VIA HISTONE MODIFICATION, DNA METHYLATION) AND POSTTRANSCRIPTIONAL LEVELS (VIA MICRORNAS AND LONG NON-CODING RNAS). THIS STUDY AIMS TO PRESENT AND DISCUSS THE DIFFERENT EPIGENETIC MECHANISMS IN PSORIASIS BASED ON A REVIEW OF THE AVAILABLE LITERATURE. 2021 15 4452 42 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 16 5561 45 ROLE OF HISTONE DEACETYLASES IN MONOCYTE FUNCTION IN HEALTH AND CHRONIC INFLAMMATORY DISEASES. HISTONE DEACETYLASES (HDACS) ARE A FAMILY OF 18 MEMBERS THAT PARTICIPATE IN THE EPIGENETIC REGULATION OF GENE EXPRESSION. IN ADDITION TO HISTONES, SOME HDACS ALSO DEACETYLATE TRANSCRIPTION FACTORS AND SPECIFIC CYTOPLASMIC PROTEINS.MONOCYTES, AS PART OF THE INNATE IMMUNE SYSTEM, MAINTAIN TISSUE HOMEOSTASIS AND HELP FIGHT INFECTIONS AND CANCER. IN THESE CELLS, HDACS ARE INVOLVED IN MULTIPLE PROCESSES INCLUDING PROLIFERATION, MIGRATION, DIFFERENTIATION, INFLAMMATORY RESPONSE, INFECTIONS, AND TUMORIGENESIS. HERE, A SYSTEMATIC DESCRIPTION OF THE ROLE THAT MOST HDACS PLAY IN THESE FUNCTIONS IS REVIEWED. SPECIFICALLY, SOME HDACS INDUCE A PRO-INFLAMMATORY RESPONSE AND PLAY MAJOR ROLES IN HOST DEFENSE. CONVERSELY, OTHER HDACS REPROGRAM MONOCYTES AND MACROPHAGES TOWARDS AN IMMUNOSUPPRESSIVE PHENOTYPE. THE RIGHT BALANCE BETWEEN BOTH TYPES HELPS MONOCYTES TO RESPOND CORRECTLY TO THE DIFFERENT PHYSIOLOGICAL/PATHOLOGICAL STIMULI. HOWEVER, ABERRANT EXPRESSIONS OR ACTIVITIES OF SPECIFIC HDACS ARE ASSOCIATED WITH AUTOIMMUNE DISEASES ALONG WITH OTHER CHRONIC INFLAMMATORY DISEASES, INFECTIONS, OR CANCER.THIS PAPER CRITICALLY REVIEWS THE INTERESTING AND EXTENSIVE KNOWLEDGE REGARDING THE ROLE OF SOME HDACS IN THESE PATHOLOGIES. IT ALSO SHOWS THAT AS YET, VERY LITTLE PROGRESS HAS BEEN MADE TOWARD THE GOAL OF FINDING EFFECTIVE HDAC-TARGETED THERAPIES. HOWEVER, GIVEN THEIR OBVIOUS POTENTIAL, WE CONCLUDE THAT IT IS WORTH THE EFFORT TO DEVELOP MONOCYTE-SPECIFIC DRUGS THAT SELECTIVELY TARGET HDAC SUBTYPES WITH THE AIM OF FINDING EFFECTIVE TREATMENTS FOR DISEASES IN WHICH OUR INNATE IMMUNE SYSTEM IS INVOLVED. 2021 17 3039 33 GENOME ENGINEERING FOR PERSONALIZED ARTHRITIS THERAPEUTICS. ARTHRITIS REPRESENTS A FAMILY OF COMPLEX JOINT PATHOLOGIES RESPONSIBLE FOR THE MAJORITY OF MUSCULOSKELETAL CONDITIONS. NEARLY ALL DISEASES WITHIN THIS FAMILY, INCLUDING OSTEOARTHRITIS, RHEUMATOID ARTHRITIS, AND JUVENILE IDIOPATHIC ARTHRITIS, ARE CHRONIC CONDITIONS WITH FEW OR NO DISEASE-MODIFYING THERAPEUTICS AVAILABLE. ADVANCES IN GENOME ENGINEERING TECHNOLOGY, MOST RECENTLY WITH CRISPR-CAS9, HAVE REVOLUTIONIZED OUR ABILITY TO INTERROGATE AND VALIDATE GENETIC AND EPIGENETIC ELEMENTS ASSOCIATED WITH CHRONIC DISEASES SUCH AS ARTHRITIS. THESE TECHNOLOGIES, TOGETHER WITH CELL REPROGRAMMING METHODS, INCLUDING THE USE OF INDUCED PLURIPOTENT STEM CELLS, PROVIDE A PLATFORM FOR HUMAN DISEASE MODELING. WE SUMMARIZE NEW EVIDENCE FROM GENOME-WIDE ASSOCIATION STUDIES AND GENOMICS THAT SUBSTANTIATES A GENETIC BASIS FOR ARTHRITIS PATHOGENESIS. WE ALSO REVIEW THE POTENTIAL CONTRIBUTIONS OF GENOME ENGINEERING IN THE DEVELOPMENT OF NEW ARTHRITIS THERAPEUTICS. 2017 18 2333 42 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 19 3703 36 INFLAMMATORY SIGNALLING AS MEDIATOR OF EPIGENETIC MODULATION IN TISSUE-SPECIFIC CHRONIC INFLAMMATION. RECENT SUCCESSES OF THERAPEUTIC INTERVENTION IN CHRONIC INFLAMMATORY DISEASES USING EPIGENETIC MODIFIERS SUCH AS HISTONE DEACETYLASE INHIBITORS AND INHIBITORS OF DNA METHYLATION SUGGEST THAT EPIGENETIC REPROGRAMMING PLAYS A ROLE IN THE AETIOLOGY OF THESE DISEASES. THE EPIGENETIC SIGNATURE OF A GIVEN IMMUNE CELL IS REFLECTED IN THE HISTORY OF MODIFICATIONS FROM DIFFERENT SIGNALS THE CELL HAS BEEN SUBJECTED TO DURING DIFFERENTIATION. LIKE OTHER CELLS, DIFFERENTIATING IMMUNE CELLS ARE DEPENDENT ON A COMPLEX COMBINATION OF INTER- AND INTRACELL SIGNALLING AS WELL AS TRANSCRIPTION MACHINERIES TO MODULATE THEIR EPIGENOMES IN ORDER TO MEDIATE DIFFERENTIATION. DESPITE EXTENSIVE RESEARCH INTO THESE PROCESSES, THE LINK BETWEEN CELLULAR SIGNALLING AND EPIGENETIC MODULATION REMAINS POORLY UNDERSTOOD. HERE, WE REVIEW RECENT PROGRESS AND DISCUSS KEY FACTORS DRIVING EPIGENETIC MODULATION IN CHRONIC INFLAMMATION. 2009 20 4961 41 PATHOGENESIS OF PSORIASIS IN THE "OMIC" ERA. PART II. GENETIC, GENOMIC AND EPIGENETIC CHANGES IN PSORIASIS. PSORIASIS IS A MULTIFACTORIAL DISEASE IN WHICH GENETIC, ENVIRONMENTAL AND EPIGENETIC FACTORS REGULATING GENE EXPRESSION PLAY A KEY ROLE. IN THE "GENOMIC ERA", GENOME-WIDE ASSOCIATION STUDIES TOGETHER WITH TARGET GENOTYPING PLATFORMS PERFORMED IN DIFFERENT ETHNIC POPULATIONS HAVE FOUND MORE THAN 50 GENETIC SUSCEPTIBLE MARKERS ASSOCIATED WITH THE RISK OF PSORIASIS WHICH HAVE BEEN IDENTIFIED SO FAR. UP TILL NOW, THE STRONGEST ASSOCIATION WITH THE RISK OF THE DISEASE HAS BEEN PROVED FOR HLA-C*06 GENE. THE MAJORITY OF OTHER PSORIASIS RISK SNPS ARE SITUATED NEAR THE GENES ENCODING MOLECULES INVOLVED IN ADAPTIVE AND INNATE IMMUNITY, AND SKIN BARRIER FUNCTION. MANY CONTEMPORARY STUDIES INDICATE THAT THE EPIGENETIC CHANGES: HISTONE MODIFICATION, PROMOTER METHYLATIONS, LONG NON-CODING AND MICRO-RNA HYPEREXPRESSION ARE CONSIDERED AS FACTORS CONTRIBUTING TO PSORIASIS PATHOGENESIS AS THEY REGULATE ABNORMAL KERATINOCYTE DIFFERENTIATION AND PROLIFERATION, ABERRANT KERATINOCYTES - INFLAMMATORY CELLS COMMUNICATION, NEOANGIOGENESIS AND CHRONIC INFLAMMATION. THE CIRCULATING MIRNAS DETECTED IN THE BLOOD MAY BECOME SPECIFIC MARKERS IN THE DIAGNOSIS, PROGNOSIS AND RESPONSE TO THE TREATMENT OF THE DISEASE. THE INHIBITION OF EXPRESSION IN SELECTED MIRNAS MAY BE A NEW PROMISING THERAPY OPTION FOR PATIENTS WITH PSORIASIS. 2020