1 4452 91 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 2 297 28 AIM2 AND PSORIASIS. PSORIASIS IS A CHRONIC INFLAMMATORY SKIN DISEASE OCCURRING WORLDWIDE, WITH MULTIPLE SYSTEMIC COMPLICATIONS, WHICH SERIOUSLY AFFECT THE QUALITY OF LIFE AND PHYSICAL AND MENTAL HEALTH OF PATIENTS. THE PATHOGENESIS OF PSORIASIS IS RELATED TO THE ENVIRONMENT, GENETICS, EPIGENETICS, AND DYSREGULATION OF IMMUNE CELLS SUCH AS T CELLS, DENDRITIC CELLS (DCS), AND NONIMMUNE CELLS SUCH AS KERATINOCYTES. ABSENT IN MELANOMA 2 (AIM2), A SUSCEPTIBILITY GENE LOCUS FOR PSORIASIS, HAS BEEN STRONGLY LINKED TO THE GENETIC AND EPIGENETIC ASPECTS OF PSORIASIS AND INCREASED IN EXPRESSION IN PSORIATIC KERATINOCYTES. AIM2 WAS FOUND TO BE ACTIVATED IN AN INFLAMMASOME-DEPENDENT WAY TO RELEASE IL-1BETA AND IL-18 TO MEDIATE INFLAMMATION, AND TO PARTICIPATE IN IMMUNE REGULATION IN PSORIASIS, OR IN AN INFLAMMASOME-INDEPENDENT WAY BY REGULATING THE FUNCTION OF REGULATORY T(TREG) CELLS OR PROGRAMMING CELL DEATH IN KERATINOCYTES AS WELL AS CONTROLLING THE PROLIFERATIVE STATE OF DIFFERENT CELLS. AIM2 MAY ALSO PLAY A ROLE IN THE RECURRENCE OF PSORIASIS BY TRAINED IMMUNITY. IN THIS REVIEW, WE WILL ELABORATE ON THE CHARACTERISTICS OF AIM2 AND HOW AIM2 MEDIATES THE DEVELOPMENT OF PSORIASIS. 2023 3 258 28 ADVANCES IN PATHOGENESIS AND NANOPARTICLES (NPS)-MEDIATED TREATMENT OF PSORIASIS. PSORIASIS IS A CHRONIC PAPULOSQUAMOUS SKIN DISEASE WITH AN AUTOIMMUNE PATHOGENIC TRAITS AND STRONG GENETIC PREDISPOSITION. IN THE PAST FEW DECADES, WITH THE RAPID DEVELOPMENT OF MOLECULAR BIOLOGY AND CELL BIOLOGY, THE INHERENT PATHOGENESIS OF PSORIASIS HAS BEEN GRADUALLY ELUCIDATED, IN WHICH CYTOKINE INFLAMMATORY LOOPS, CELL SIGNALING PATHWAYS, AND EPIGENETIC FACTORS SUCH AS MIRNAS HAVE BEEN DEMONSTRATED TO PLAY IMPORTANT ROLES IN REGULATING THE DEVELOPMENT AND PROGRESSION OF PSORIASIS. MORE IMPORTANTLY, UNDERSTANDING THE PATHOGENESIS OF PSORIASIS HAS PROMOTED THE DEVELOPMENT OF EFFECTIVE TREATMENT FOR PSORIASIS. IN THIS REVIEW, WE SYSTEMICALLY SUMMARIZED THE MOLECULAR MECHANISMS REGULATING THE DEVELOPMENT AND PROGRESSION PSORIASIS, INTRODUCED VARIOUS THERAPEUTICS USED FOR CLINICAL PSORIASIS THERAPY, AND HIGHLIGHTED THE RECENT ADVANCES IN NANOPARTICLES (NPS)-MEDIATED DRUG DELIVERY FOR PSORIASIS TREATMENT. 2022 4 6210 38 THE INTERPLAY BETWEEN KERATINOCYTES AND IMMUNE CELLS IN THE PATHOGENESIS OF PSORIASIS. PSORIASIS IS A CHRONIC INFLAMMATORY SKIN DISEASE RESULTING FROM GENETIC, EPIGENETIC, ENVIRONMENTAL, AND LIFESTYLE FACTORS. TO DATE, SEVERAL IMMUNOPATHOGENIC MECHANISMS OF PSORIASIS HAVE BEEN ELUCIDATED, AND, IN THE CURRENT MODEL, THE CROSS TALK BETWEEN AUTOREACTIVE T CELLS AND RESIDENT KERATINOCYTES GENERATES INFLAMMATORY AND IMMUNE CIRCUITS RESPONSIBLE FOR THE INITIATION, PROGRESSION, AND PERSISTENCE OF THE DISEASE. SEVERAL AUTOANTIGENS DERIVED FROM KERATINOCYTES (I.E., LL37 CATHELECIDIN/NUCLEIC ACID COMPLEXES, NEWLY GENERATED LIPID ANTIGENS) HAVE BEEN IDENTIFIED, WHICH MAY TRIGGER INITIAL ACTIVATION OF T CELLS, PARTICULARLY IL-17-PRODUCING T CELLS, T HELPER (TH)1 AND TH22 CELLS. HENCE, LYMPHOKINES RELEASED IN SKIN LESIONS ARE PIVOTAL FOR KERATINOCYTE ACTIVATION AND PRODUCTION OF INFLAMMATORY MOLECULES, WHICH IN TURN LEAD TO AMPLIFICATION OF THE LOCAL IMMUNE RESPONSES. INTRINSIC GENETIC ALTERATIONS OF KERATINOCYTES IN THE ACTIVATION OF SIGNAL TRANSDUCTION PATHWAYS DEPENDENT ON T-CELL-DERIVED CYTOKINES ARE ALSO FUNDAMENTAL. THE CURRENT REVIEW EMPHASIZES THE ABERRANT INTERPLAY OF IMMUNE CELLS AND SKIN-RESIDENT KERATINOCYTES IN ESTABLISHING AND SUSTAINING INFLAMMATORY AND IMMUNE RESPONSES IN PSORIASIS. 2018 5 2063 23 EPIGENETIC CONTROL OF IL-23 EXPRESSION IN KERATINOCYTES IS IMPORTANT FOR CHRONIC SKIN INFLAMMATION. THE CHRONIC SKIN INFLAMMATION PSORIASIS IS CRUCIALLY DEPENDENT ON THE IL-23/IL-17 CYTOKINE AXIS. ALTHOUGH IL-23 IS EXPRESSED BY PSORIATIC KERATINOCYTES AND IMMUNE CELLS, ONLY THE IMMUNE CELL-DERIVED IL-23 IS BELIEVED TO BE DISEASE RELEVANT. HERE WE USE A GENETIC MOUSE MODEL TO SHOW THAT KERATINOCYTE-PRODUCED IL-23 IS SUFFICIENT TO CAUSE A CHRONIC SKIN INFLAMMATION WITH AN IL-17 PROFILE. FURTHERMORE, WE REVEAL A CELL-AUTONOMOUS NUCLEAR FUNCTION FOR THE ACTIN POLYMERIZING MOLECULE N-WASP, WHICH CONTROLS IL-23 EXPRESSION IN KERATINOCYTES BY REGULATING THE DEGRADATION OF THE HISTONE METHYLTRANSFERASES G9A AND GLP, AND H3K9 DIMETHYLATION OF THE IL-23 PROMOTER. THIS MECHANISM MEDIATES THE INDUCTION OF IL-23 BY TNF, A KNOWN INDUCER OF IL-23 IN PSORIASIS. FINALLY, IN KERATINOCYTES OF PSORIATIC LESIONS A DECREASE IN H3K9 DIMETHYLATION CORRELATES WITH INCREASED IL-23 EXPRESSION, SUGGESTING RELEVANCE FOR DISEASE. TAKEN TOGETHER, OUR DATA DESCRIBE A MOLECULAR PATHWAY WHERE EPIGENETIC REGULATION OF KERATINOCYTES CAN CONTRIBUTE TO CHRONIC SKIN INFLAMMATION. 2018 6 5594 26 ROLES OF AIM2 GENE AND AIM2 INFLAMMASOME IN THE PATHOGENESIS AND TREATMENT OF PSORIASIS. PSORIASIS IS AN IMMUNE-MEDIATED CHRONIC INFLAMMATORY SKIN DISEASE CAUSED BY A COMBINATION OF ENVIRONMENTAL INCENTIVES, POLYGENIC GENETIC CONTROL, AND IMMUNE REGULATION. THE INFLAMMATION-RELATED GENE ABSENT IN MELANOMA 2 (AIM2) WAS IDENTIFIED AS A SUSCEPTIBILITY GENE FOR PSORIASIS. AIM2 INFLAMMASOME FORMED FROM THE COMBINATION OF AIM2, PYD-LINKED APOPTOSIS-ASSOCIATED SPECK-LIKE PROTEIN (ASC) AND CASPASE-1 PROMOTES THE MATURATION AND RELEASE OF INFLAMMATORY CYTOKINES SUCH AS IL-1BETA AND IL-18, AND TRIGGERS AN INFLAMMATORY RESPONSE. STUDIES SHOWED THE GENETIC AND EPIGENETIC ASSOCIATIONS BETWEEN AIM2 GENE AND PSORIASIS. AIM2 GENE HAS AN ESSENTIAL ROLE IN THE OCCURRENCE AND DEVELOPMENT OF PSORIASIS, AND THE INHIBITORS OF AIM2 INFLAMMASOME WILL BE NEW THERAPEUTIC TARGETS FOR PSORIASIS. IN THIS REVIEW, WE SUMMARIZED THE ROLES OF THE AIM2 GENE AND AIM2 INFLAMMASOME IN PATHOGENESIS AND TREATMENT OF PSORIASIS, HOPEFULLY PROVIDING A BETTER UNDERSTANDING AND NEW INSIGHT INTO THE ROLES OF AIM2 GENE AND AIM2 INFLAMMASOME IN PSORIASIS. 2022 7 2726 35 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 8 5309 29 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 9 555 25 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 10 4883 31 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 11 2553 31 EPIGENETICS IN PSORIASIS: PERSPECTIVE OF DNA METHYLATION. PSORIASIS IS A CHRONIC INFLAMMATORY SKIN DISEASE CHARACTERIZED BY EXCESSIVE PROLIFERATION OF KERATINOCYTES (KCS). ONSET OF PSORIASIS IS RELATED TO GENETIC, IMMUNE AND ENVIRONMENTAL FACTORS. THE ENVIRONMENT CAN INTERACT WITH THE GENOME THROUGH EPIGENETIC MODIFICATIONS, INCLUDING DNA METHYLATION, AND THIS MODIFICATION IS INVOLVED IN THE PATHOGENESIS OF PSORIASIS. IN ADDITION TO A SKIN DISEASE, PSORIASIS IS ALSO CONSIDERED A SYSTEMIC DISEASE. WE REVIEWED THE CURRENT LITERATURE OF PSORIATIC DNA METHYLATION FOR STUDIES FROM SEVERAL ASPECTS ON THE DNA METHYLATION DISTRIBUTION PATTERNS IN DIFFERENT TISSUES/CELLS, SINGLE-NUCLEOTIDE POLYMORPHISMS, AND CANDIDATE DISEASE GENES AND IDENTIFIED TARGET GENES REGULATED BY DNA METHYLATION THAT HAVE BEEN DIRECTLY/INDIRECTLY VALIDATED. THIS REVIEW CONTRIBUTES TO A COMPREHENSIVE UNDERSTANDING OF THE IMPORTANT A ROLE THAT DNA METHYLATION PLAYS IN PSORIASIS FROM A HOLISTIC PERSPECTIVE AND WILL PROMOTE THE IMPLEMENTATION OF DNA METHYLATION IN DIAGNOSTIC AND THERAPEUTIC STRATEGIES FOR PSORIATIC PATIENTS. 2021 12 3645 22 INCREASED PRESENCE AND DIFFERENTIAL MOLECULAR IMPRINTING OF TRANSIT AMPLIFYING CELLS IN PSORIASIS. PSORIASIS IS A VERY COMMON CHRONIC INFLAMMATORY SKIN DISEASE CHARACTERIZED BY EPIDERMAL THICKENING AND SCALING RESULTING FROM KERATINOCYTE HYPERPROLIFERATION AND IMPAIRED DIFFERENTIATION. PATHOMECHANISTIC STUDIES IN PSORIASIS ARE OFTEN LIMITED BY USING WHOLE SKIN TISSUE BIOPSIES, NEGLECTING THEIR STRATIFICATION AND CELLULAR DIVERSITY. THIS STUDY AIMED AT CHARACTERIZING EPIDERMAL ALTERATIONS IN PSORIASIS AT THE LEVEL OF KERATINOCYTE POPULATIONS. EPIDERMAL CELL POPULATIONS WERE PURIFIED FROM SKIN BIOPSIES OF PSORIASIS PATIENTS AND HEALTHY DONORS USING A NOVEL CELL TYPE-SPECIFIC APPROACH. MOLECULAR CHARACTERIZATION OF THE TRANSIT-AMPLIFYING CELLS (TAC), THE KEY PLAYERS OF EPIDERMAL RENEWAL, WAS PERFORMED USING IMMUNOCYTOFLUORESCENCE-TECHNIQUE AND INTEGRATED MULTISCALE-OMICS ANALYSES. ALREADY TAC FROM NON-LESIONAL PSORIATIC SKIN SHOWED ALTERED METHYLATION AND DIFFERENTIAL EXPRESSION IN 1.7% AND 1.0% OF ALL PROTEIN-CODING GENES, RESPECTIVELY. IN PSORIATIC LESIONS, TAC WERE STRONGLY EXPANDED SHOWING FURTHER INCREASED DIFFERENTIALLY METHYLATED (10-FOLD) AND EXPRESSED (22-FOLD) GENES NUMBERS. IMPORTANTLY, 17.2% OF DIFFERENTIALLY EXPRESSED GENES WERE ASSOCIATED WITH RESPECTIVE GENE METHYLATIONS. COMPARED WITH NON-LESIONAL TAC, PATHWAY ANALYSES REVEALED METABOLIC ALTERATIONS AS ONE FEATURE PREDOMINANTLY CHANGED IN TAC DERIVED FROM ACTIVE PSORIATIC LESIONS. OVERALL, OUR STUDY SHOWED STAGE-SPECIFIC MOLECULAR ALTERATIONS, ALLOWS NEW INSIGHTS INTO THE PATHOGENESIS, AND IMPLIES THE INVOLVEMENT OF EPIGENETIC MECHANISMS IN LESION DEVELOPMENT IN PSORIASIS. KEY MESSAGES: TRANSIT AMPLIFYING CELL (TAC) NUMBERS ARE HIGHLY INCREASED IN PSORIATIC LESIONS PSORIATIC TAC SHOW PROFOUND MOLECULAR ALTERATIONS & STAGE-SPECIFIC IDENTITY TAC FROM UNAFFECTED AREAS ALREADY SHOW FIRST SIGNS OF MOLECULAR ALTERATIONS LESIONAL TAC SHOW A PREFERENCE IN METABOLIC-RELATED ALTERATIONS. 2020 13 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 14 6202 44 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 15 4756 42 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 16 6624 33 UNDERSTANDING PSORIASIS: ROLE OF MIRNAS. PSORIASIS IS A CHRONIC, IMMUNE-MEDIATED INFLAMMATORY SKIN DISEASE, WITH A MULTIFACTORIAL ETIOLOGY AND IMPORTANT IMMUNOLOGIC, GENETIC AND ENVIRONMENTAL COMPONENTS. PSORIASIS VULGARIS REPRESENTS ITS MOST COMMON FORM, WITH A VARIABLE PREVALENCE ACROSS THE GLOBE. ALTHOUGH ITS PATHOGENESIS REMAINS TO BE FULLY ELUCIDATED, A LACK OF BALANCE IN THE EPIGENETIC NETWORK HAS BEEN SHOWN TO TRIGGER CERTAIN ELEMENTS OF THIS DISEASE, POSSIBLY ALTERING ITS OUTCOME. MICRORNAS ARE SMALL NON-CODING RNA MOLECULES INVOLVED IN RNA-SILENCING AND THE POST-TRANSCRIPTIONAL REGULATION OF GENE EXPRESSION, WHICH ALSO APPEAR TO MEDIATE THE IMMUNE DYSFUNCTION IN PSORIASIS. ALTHOUGH MICRORNA RESEARCH IS A NEW FIELD IN DERMATOLOGY AND PSORIASIS, THERE IS RAPIDLY ACCUMULATING EVIDENCE FOR ITS MAJOR CONTRIBUTION IN THE PATHOGENESIS OF CHRONIC INFLAMMATORY CONDITIONS, INCLUDING PSORIASIS AND OTHER DERMATOLOGICAL DISORDERS. FURTHERMORE, CIRCULATING MIRNAS IDENTIFIED IN PATIENTS' BLOOD SAMPLES HAVE BEEN IDENTIFIED AS PROMISING BIOMARKERS OF DIAGNOSIS, PROGNOSIS OR TREATMENT RESPONSE. EXTENDED INVESTIGATIONS IN THIS FIELD ARE REQUIRED, AS UNTIL NOW, THE EXACT INVOLVEMENT OF MIRNAS IN PSORIASIS HAVE REMAINED TO BE ENTIRELY ELUCIDATED. THIS SHORT REVIEW HIGHLIGHTS A NUMBER OF THE ROLES OF MIRNAS FOUND IN DIFFERENT STAGES OF PSORIASIS. 2018 17 5998 28 THE ABERRANT EPIGENETIC MODIFICATIONS IN THE PATHOGENESIS OF PSORIASIS. PSORIASIS IS A CHRONIC AND RECURRENT INFLAMMATORY SKIN DISEASE THAT IS CHARACTERIZED BY ABNORMAL KERATINOCYTE PROLIFERATION, VASCULAR HYPERPLASIA, AND INFILTRATION OF INFLAMMATORY CELLS INTO THE DERMIS AND EPIDERMIS. IT IS GENERALLY ACCEPTED THAT THE CENTRAL PATHOGENESIS OF PSORIASIS IS DYSFUNCTION OF T LYMPHOCYTES, WHICH ARE AFFECTED BY THE COMPLEX INTERPLAY BETWEEN GENETIC AND ENVIRONMENTAL FACTORS, INCLUDING TRAUMA, INFECTIONS, STRESS, DRUGS, SMOKING, AND ALCOHOL CONSUMPTION (NESTLE ET AL., 2009). THE ENVIRONMENTALLY INDUCED EPIGENETIC CHANGES, INCLUDING DNA METHYLATION, HISTONE MODIFICATION, AND MICRORNAS, HAVE BEEN SHOWN TO BE INVOLVED IN THE PATHOGENESIS OF THIS DISEASE (ZHANG ET AL., 2012). 2018 18 2082 24 EPIGENETIC DOWNREGULATION OF SFRP4 CONTRIBUTES TO EPIDERMAL HYPERPLASIA IN PSORIASIS. PSORIASIS IS A CHRONIC RECURRENT INFLAMMATORY SKIN DISORDER CHARACTERIZED BY THE DYSREGULATED CROSS-TALK BETWEEN EPIDERMAL KERATINOCYTES AND IMMUNE CELLS, LEADING TO KERATINOCYTE HYPERPROLIFERATION. SEVERAL STUDIES DEMONSTRATED THAT WNT PATHWAY GENES WERE DIFFERENTIALLY EXPRESSED IN PSORIATIC PLAQUES AND LIKELY WERE INVOLVED IN THE PATHOPHYSIOLOGY OF DISEASE. HOWEVER, THE MOLECULAR MECHANISMS UNDERLYING WNT SIGNALING REGULATION IN EPIDERMAL HYPERPLASIA IN PSORIASIS REMAIN LARGELY UNKNOWN. WE REPORT THAT THE EXPRESSION OF SECRETED FRIZZLED-RELATED PROTEIN (SFRP) 4, A NEGATIVE REGULATOR OF THE WNT SIGNALING PATHWAY, WAS DIMINISHED IN LESIONAL SKIN OF MOUSE MODELS AND PATIENTS WITH PSORIASIS. SFRP4 DIRECTLY INHIBITED EXCESSIVE KERATINOCYTE PROLIFERATION EVOKED BY PROINFLAMMATORY CYTOKINES IN VITRO. PHARMACOLOGICAL INHIBITION OF WNT SIGNALING OR INTRADERMAL INJECTION OF SFRP4 DECREASED THE SEVERITY OF THE PSORIASIFORM SKIN PHENOTYPE IN VIVO, INCLUDING DECREASED ACANTHOSIS AND REDUCED LEUKOCYTE INFILTRATION. MECHANISTICALLY, WE IDENTIFIED THAT ABERRANT PROMOTER METHYLATION RESULTED IN EPIGENETIC DOWNREGULATION OF SFRP4 IN INFLAMED SKIN OF PATIENTS WITH PSORIASIS AND IN THE IL-23-INDUCED MOUSE MODEL. OUR FINDINGS SUGGEST THAT THIS EPIGENETIC EVENT IS CRITICALLY INVOLVED IN THE PATHOGENESIS OF PSORIASIS, AND THE DOWNREGULATION OF SFRP4 BY CPG ISLAND METHYLATION IS ONE POSSIBLE MECHANISM CONTRIBUTING TO THE HYPERPLASIA OF EPIDERMIS IN THE DISEASE. 2015 19 3838 26 IOX1 IMPEDES HOST INFLAMMATION IN IMIQUIMOD-TRIGGERED PSORIASIS. PSORIASIS IS A CHRONIC AUTOIMMUNE DISEASE WITH AN UNKNOWN ETIOLOGY AND HIGHLY LIMITED TREATMENT STRATEGIES. THE DRUGS CURRENTLY USED IN THE TREATMENT OF PSORIASIS ARE RARELY RECOMMENDED FOR LONG-TERM USE OWING TO THE SERIOUS SIDE EFFECTS. ALTHOUGH DIFFERENT TARGETS HAVE BEEN IDENTIFIED FOR CONTROLLING PSORIASIS, THE ROLE OF EPIGENETIC MODIFICATIONS AS THERAPEUTIC TARGETS IS YET TO BE ELUCIDATED. HERE, WE INVESTIGATED THE THERAPEUTIC POTENTIAL OF 8-HYDROXYQUINOLINE-5-CARBOXYLIC ACID (IOX1), A NOVEL DRUG WITH A GENETIC TARGET, IN PSORIASIS. THE DAILY TOPICAL ADMINISTRATION OF IOX1 IN A MOUSE MODEL OF IMIQUIMOD (IMQ)-INDUCED PSORIATIC INFLAMMATION REDUCED INFLAMMATORY REACTIONS IN THE SKIN AND LOWERED THE PASI SCORE. FURTHERMORE, INTRAPERITONEALLY INJECTED IOX1 REPRESSED THE INFLAMMATORY STATUS INDUCED BY IMQ IN PSORIATIC MICE BY REDUCING THE MRNA LEVELS OF PRO-INFLAMMATORY CYTOKINES, RESTORING SPLENOCYTE POPULATIONS, AND REGULATING MACROPHAGE POLARIZATION. OUR FINDINGS INDICATE THE REMEDIAL EFFECTS OF IOX1 ON DERMATITIS PSORIASIS AND THE POTENTIAL OF IOX1 AS A THERAPEUTIC COMPOUND IN PSORIASIS. 2021 20 1570 26 DNA METHYLATION PATTERNS IN CD4(+) T-CELLS SEPARATE PSORIASIS PATIENTS FROM HEALTHY CONTROLS, AND SKIN PSORIASIS FROM PSORIATIC ARTHRITIS. BACKGROUND: PSORIASIS IS AN AUTOIMMUNE/INFLAMMATORY DISORDER PRIMARILY AFFECTING THE SKIN. CHRONIC JOINT INFLAMMATION TRIGGERS THE DIAGNOSIS OF PSORIATIC ARTHRITIS (PSA) IN APPROXIMATELY ONE-THIRD OF PSORIASIS PATIENTS. ALTHOUGH JOINT DISEASE TYPICALLY FOLLOWS THE ONSET OF SKIN PSORIASIS, IN AROUND 15% OF CASES IT IS THE INITIAL PRESENTATION, WHICH CAN RESULT IN DIAGNOSTIC DELAYS. THE PATHOPHYSIOLOGICAL MECHANISMS UNDERLYING PSORIASIS AND PSA ARE NOT YET FULLY UNDERSTOOD, BUT THERE IS EVIDENCE POINTING TOWARDS EPIGENETIC DYSREGULATION INVOLVING CD4(+) AND CD8(+) T-CELLS. OBJECTIVES: THE AIM OF THIS STUDY WAS TO INVESTIGATE DISEASE-ASSOCIATED DNA METHYLATION PATTERNS IN CD4(+) T-CELLS FROM PSORIASIS AND PSA PATIENTS THAT MAY REPRESENT POTENTIAL DIAGNOSTIC AND/OR PROGNOSTIC BIOMARKERS. METHODS: PBMCS WERE COLLECTED FROM 12 PATIENTS WITH CHRONIC PLAQUE PSORIASIS AND 8 PSA PATIENTS, AND 8 HEALTHY CONTROLS. CD4(+) T-CELLS WERE SEPARATED THROUGH FACS SORTING, AND DNA METHYLATION PROFILING WAS PERFORMED (ILLUMINA EPIC850K ARRAYS). BIOINFORMATIC ANALYSES, INCLUDING GENE ONTOLOGY (GO) AND KEGG PATHWAY ANALYSIS, WERE PERFORMED USING R. TO IDENTIFY GENES UNDER THE CONTROL OF INTERFERON (IFN), THE INTERFEROME DATABASE WAS CONSULTED, AND DNA METHYLATION SCORES WERE CALCULATED. RESULTS: NUMBERS AND PROPORTIONS OF CD4(+) T-CELL SUBSETS (NAIVE, CENTRAL MEMORY, EFFECTOR MEMORY, CD45RA RE-EXPRESSING EFFECTOR MEMORY CELLS) DID NOT VARY BETWEEN CONTROLS, SKIN PSORIASIS AND PSA PATIENTS. 883 DIFFERENTIALLY METHYLATED POSITIONS (DMPS) AFFECTING 548 GENES WERE IDENTIFIED BETWEEN CONTROLS AND "ALL" PSORIASIS PATIENTS. PRINCIPAL COMPONENT AND PARTIAL LEAST-SQUARES DISCRIMINANT ANALYSIS SEPARATED CONTROLS FROM SKIN PSORIASIS AND PSA PATIENTS. GO ANALYSIS CONSIDERING PROMOTER DMPS DELIVERED HYPERMETHYLATION OF GENES INVOLVED IN "REGULATION OF WOUND HEALING, SPREADING OF EPIDERMAL CELLS", "NEGATIVE REGULATION OF CELL-SUBSTRATE JUNCTION ORGANIZATION" AND "NEGATIVE REGULATION OF FOCAL ADHESION ASSEMBLY". COMPARING CONTROLS AND "ALL" PSORIASIS, A MAJORITY OF DMPS MAPPED TO IFN-RELATED GENES (69.2%). NOTABLY, DNA METHYLATION PROFILES ALSO DISTINGUISHED SKIN PSORIASIS FROM PSA PATIENTS (2,949 DMPS/1,084 GENES) THROUGH GENES AFFECTING "CAMP-DEPENDENT PROTEIN KINASE INHIBITOR ACTIVITY" AND "CAMP-DEPENDENT PROTEIN KINASE REGULATOR ACTIVITY". TREATMENT WITH CYTOKINE INHIBITORS (IL-17/TNF) CORRECTED DNA METHYLATION PATTERNS OF IL-17/TNF-ASSOCIATED GENES, AND METHYLATION SCORES CORRELATED WITH SKIN DISEASE ACTIVITY SCORES (PASI). CONCLUSION: DNA METHYLATION PROFILES IN CD4(+) T-CELLS DISCRIMINATE BETWEEN SKIN PSORIASIS AND PSA. DNA METHYLATION SIGNATURES MAY BE APPLIED FOR QUANTIFICATION OF DISEASE ACTIVITY AND PATIENT STRATIFICATION TOWARDS INDIVIDUALIZED TREATMENT. 2023