1 2726 107 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 2 4756 49 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 3 5309 33 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 4 6202 40 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 5 4452 35 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 6 4883 32 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 7 2591 32 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 8 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 9 6343 31 THE ROLE OF EPIGENETICS AND IMMUNOLOGICAL IMBALANCE IN THE ETIOPATHOGENESIS OF PSORIASIS AND PSORIATIC ARTHRITIS. PSORIASIS (PS) AND PSORIATIC ARTHRITIS (PSA) REPRESENT A CLINICAL AND IMMUNOPATHOGENIC CONTINUUM, CALLED PSORIATIC DISEASE, CUMULATIVELY AFFECTING APPROXIMATELY 3% OF THE GENERAL POPULATION. PSORIATIC DISEASE IS A CHRONIC INFLAMMATORY DISORDER AFFECTING THE SKIN AND MUSCULOSKELETAL SYSTEM. THE IMMUNO-PATHOGENESIS IS CHARACTERIZED BY AN ACTIVATION OF THE TNF/IL-23/IL-17 CYTOKINE AXIS, LEADING TO AN IMMUNOLOGIC IMBALANCE OF T-CELLS RESIDENT IN ALL AFFECTED TISSUES, MAINLY ENTHESES. IN THE MAJORITY OF CASES, SKIN PS PREDATES RHEUMATOLOGICAL MANIFESTATIONS. SECONDARY TO THE HIGHER INCIDENCE AND THE AVAILABILITY OF MOUSE MODELS, THERE IS STRONGER DATA AVAILABLE ON SKIN PS, AND DATA ARE, IN MOST CASES, RELEVANT ALSO TO PSA. IN A WIDELY ACCEPTED MODEL, ENVIRONMENTAL TRIGGER FACTORS LIKE INFECTIONS OR TRAUMA ARE CAPABLE OF INITIATING AN INFLAMMATORY CASCADE, ULTIMATELY CREATING A SUSTAINED STATE OF CHRONIC INFLAMMATION IN GENETICALLY SUSCEPTIBLE INDIVIDUALS. BESIDES WELL-KNOWN GENETIC SUSCEPTIBILITY LOCI, EPIGENETIC DNA MODIFICATIONS, WHICH ARE ASSOCIATED WITH PS DEVELOPMENT HAVE BEEN CHARACTERIZED RECENTLY AND WILL BE DISCUSSED IN THIS ARTICLE. THE CURRENT EVIDENCE IS PROMISING IN THE POSSIBILITY TO PROVIDE NEW THERAPEUTIC AVENUES AND FILL THE UNMET NEED OF PATIENTS, FOR WHOM CURRENT TREATMENTS EITHER DO NOT ALLOW THE DISEASE TO BE CONTROLLED OR MUST BE CONTINUED FOR LIFE. 2019 10 2945 21 GENETIC AND EPIGENETIC BASIS OF PSORIASIS PATHOGENESIS. PSORIASIS IS A CHRONIC INFLAMMATORY SKIN DISEASE WHOSE PREVALENCE VARIES AMONG DIFFERENT POPULATIONS WORLDWIDE. IT IS A COMPLEX MULTI-FACTORIAL DISEASE AND THE EXACT ETIOLOGY IS LARGELY UNKNOWN. FAMILY BASED STUDIES HAVE INDICATED A GENETIC PREDISPOSITION; HOWEVER THEY CANNOT FULLY EXPLAIN THE DISEASE PATHOGENESIS. IN ADDITION TO GENETIC SUSCEPTIBILITY, ENVIRONMENTAL AS WELL AS GENDER AND AGE RELATED FACTORS WERE ALSO BEEN FOUND TO BE ASSOCIATED. RECENTLY, IMBALANCES IN EPIGENETIC NETWORKS ARE INDICATED TO BE CAUSATIVE ELEMENTS IN PSORIASIS. THE PRESENT KNOWLEDGE OF EPIGENETIC INVOLVEMENT, MAINLY THE DNA METHYLATION, CHROMATIN MODIFICATIONS AND MIRNA DEREGULATION IS SURVEYED HERE. AN INTEGRATED APPROACH CONSIDERING GENETIC AND EPIGENETIC ANOMALIES IN THE LIGHT OF IMMUNOLOGICAL NETWORK MAY EXPLORE THE PATHOGENESIS OF PSORIASIS. 2015 11 6114 32 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 12 1172 33 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 13 4961 27 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 14 6142 33 THE EVALUATION OF CYTOKINES TO HELP ESTABLISH DIAGNOSIS AND GUIDE TREATMENT OF AUTOINFLAMMATORY AND AUTOIMMUNE DISEASES. OUR KNOWLEDGE OF THE ROLE OF CYTOKINES IN PATHOLOGIC CONDITIONS HAS INCREASED CONSIDERABLY WITH THE EMERGENCE OF MOLECULAR AND GENETIC STUDIES, PARTICULARLY IN THE CASE OF AUTOINFLAMMATORY MONOGENIC DISEASES. MANY RARE DISORDERS, CONSIDERED ORPHAN UNTIL RECENTLY, ARE DIRECTLY RELATED TO ABNORMAL GENE REGULATION, AND THE TREATMENT WITH BIOLOGIC AGENTS (BIOLOGICS) TARGETING CYTOKINE RECEPTORS, INTRACELLULAR SIGNALING OR SPECIFIC CYTOKINES IMPROVE THE SYMPTOMS OF AN INCREASING NUMBER OF CHRONIC INFLAMMATORY DISEASES. AS IT IS CURRENTLY IMPOSSIBLE TO SYSTEMATICALLY CONDUCT GENETIC STUDIES FOR ALL PATIENTS WITH AUTOINFLAMMATORY AND AUTOIMMUNE DISEASES, THE EVALUATION OF CYTOKINES CAN BE SEEN AS A SIMPLE, LESS TIME CONSUMING, AND LESS EXPENSIVE ALTERNATIVE. THIS APPROACH COULD BE ESPECIALLY USEFUL WHEN THE DIAGNOSIS OF SYNDROMES OF DISEASES OF UNKNOWN ETIOLOGY REMAINS PROBLEMATIC. THE EVALUATION OF CYTOKINES COULD ALSO HELP AVOID THE CURRENT TRIAL-AND-ERROR APPROACH, WHICH HAS THE DISADVANTAGES OF EXPOSING PATIENTS TO INEFFECTIVE DRUGS WITH POSSIBLE UNNECESSARY SIDE EFFECTS AND PERMANENT ORGAN DAMAGES. IN THIS REVIEW, WE DISCUSS THE VARIOUS POSSIBILITIES, AS WELL AS THE LIMITATIONS OF EVALUATING THE CYTOKINE PROFILES OF PATIENTS SUFFERING FROM AUTOINFLAMMATORY AND AUTOIMMUNE DISEASES, WITH METHODS SUCH AS DIRECT DETECTION OF CYTOKINES IN THE PLASMA/SERUM OR FOLLOWING EX VIVO STIMULATION OF PBMCS LEADING TO THE PRODUCTION OF THEIR CYTOKINE SECRETOME. THE PATIENTS' SECRETOME, COMBINED WITH BIOMARKERS RANGING FROM GENETIC AND EPIGENETIC ANALYSES TO IMMUNOLOGIC BIOMARKERS, MAY HELP NOT ONLY THE DIAGNOSIS BUT ALSO GUIDE THE CHOICE OF BIOLOGICS FOR MORE EFFICIENT AND RAPID TREATMENTS. 2020 15 3038 30 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 16 3541 29 IMMUNOEPIGENETIC REGULATION OF INFLAMMATORY BOWEL DISEASE: CURRENT INSIGHTS INTO NOVEL EPIGENETIC MODULATIONS OF THE SYSTEMIC IMMUNE RESPONSE. THE IMMUNE SYSTEM AND ENVIRONMENTAL FACTORS ARE INVOLVED IN VARIOUS DISEASES, SUCH AS INFLAMMATORY BOWEL DISEASE (IBD), THROUGH THEIR EFFECT ON GENETICS, WHICH MODULATES IMMUNE CELLS. IBD ENCOMPASSES TWO MAIN PHENOTYPES, CROHN'S DISEASE, AND ULCERATIVE COLITIS, WHICH ARE MANIFESTED AS CHRONIC AND SYSTEMIC RELAPSE-REMITTING GASTROINTESTINAL TRACT DISORDERS WITH RISING GLOBAL INCIDENCE AND PREVALENCE. THE PATHOPHYSIOLOGY OF IBD IS COMPLEX AND NOT FULLY UNDERSTOOD. EPIGENETIC RESEARCH HAS RESULTED IN VALUABLE INFORMATION FOR UNRAVELING THE ETIOLOGY OF THIS IMMUNE-MEDIATED DISEASE. THUS, THE MAIN OBJECTIVE OF THE PRESENT REVIEW IS TO SUMMARIZE THE CURRENT FINDINGS ON THE ROLE OF EPIGENETIC MECHANISMS IN IBD TO SHED LIGHT ON THEIR POTENTIAL CLINICAL RELEVANCE. THIS REVIEW FOCUSES ON THE LATEST EVIDENCE REGARDING PERIPHERAL BLOOD MONONUCLEAR CELLS AND EPIGENETIC CHANGES IN HISTONE MODIFICATION, DNA METHYLATION, AND TELOMERE SHORTENING IN IBD. THE VARIOUS IDENTIFIED EPIGENETIC DNA PROFILES WITH CLINICAL VALUE IN IBD COULD BE USED AS BIOMARKERS FOR MORE ACCURATELY PREDICTING DISEASE DEVELOPMENT, TREATMENT RESPONSE, AND THERAPY-RELATED ADVERSE EVENTS. ULTIMATELY, THE INFORMATION PRESENTED HERE COULD BE OF POTENTIAL RELEVANCE FOR FUTURE CLINICAL PRACTICE IN DEVELOPING MORE EFFICIENT AND PRECISE MEDICINE TO IMPROVE THE QUALITY OF LIFE FOR PATIENTS WITH IBD. 2023 17 3039 28 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 26 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 6340 29 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 20 2238 32 EPIGENETIC MODULATION AS A THERAPEUTIC PROSPECT FOR TREATMENT OF AUTOIMMUNE RHEUMATIC DISEASES. SYSTEMIC INFLAMMATORY RHEUMATIC DISEASES ARE CONSIDERED AS AUTOIMMUNE DISEASES, MEANING THAT THE BALANCE BETWEEN RECOGNITION OF PATHOGENS AND AVOIDANCE OF SELF-ATTACK IS IMPAIRED AND THE IMMUNE SYSTEM ATTACKS AND DESTROYS ITS OWN HEALTHY TISSUE. TREATMENT WITH CONVENTIONAL DISEASE MODIFYING ANTIRHEUMATIC DRUGS (DMARDS) AND/OR NONSTEROIDAL ANTI-INFLAMMATORY DRUGS (NSAIDS) IS OFTEN ASSOCIATED WITH VARIOUS ADVERSE REACTIONS DUE TO UNSPECIFIC AND TOXIC PROPERTIES OF THOSE DRUGS. ALTHOUGH BIOLOGIC DRUGS HAVE LARGELY IMPROVED THE OUTCOME IN MANY PATIENTS, SUCH DRUGS STILL POSE SIGNIFICANT PROBLEMS AND FAIL TO PROVIDE A SOLUTION TO ALL PATIENTS. THEREFORE, DEVELOPMENT OF MORE EFFECTIVE TREATMENTS AND IMPROVEMENTS IN EARLY DIAGNOSIS OF RHEUMATIC DISEASES ARE BADLY NEEDED IN ORDER TO INCREASE PATIENT'S FUNCTIONING AND QUALITY OF LIFE. THE REVERSIBLE NATURE OF EPIGENETIC MECHANISMS OFFERS A NEW CLASS OF DRUGS THAT MODULATE THE IMMUNE SYSTEM AND INFLAMMATION. IN FACT, EPIGENETIC DRUGS ARE ALREADY IN USE IN SOME TYPES OF CANCER OR CARDIOVASCULAR DISEASES. THEREFORE, EPIGENETIC-BASED THERAPEUTICS THAT CONTROL AUTOIMMUNITY AND CHRONIC INFLAMMATORY PROCESS HAVE BROAD IMPLICATIONS FOR THE PATHOGENESIS, DIAGNOSIS, AND MANAGEMENT OF RHEUMATIC DISEASES. THIS REVIEW SUMMARISES THE LATEST INFORMATION ABOUT POTENTIAL THERAPEUTIC APPLICATION OF EPIGENETIC MODIFICATION IN TARGETING IMMUNE ABNORMALITIES AND INFLAMMATION OF RHEUMATIC DISEASES. 2016