1 6274 100 THE P300/CBP INHIBITOR A485 NORMALIZES PSORIATIC FIBROBLAST GENE EXPRESSION IN VITRO AND REDUCES PSORIASIS-LIKE SKIN INFLAMMATION IN VIVO. PSORIASIS IS A CHRONIC INFLAMMATORY SKIN DISEASE THAT OFTEN RECURS AT THE SAME LOCATIONS, INDICATING POTENTIAL EPIGENETIC CHANGES IN LESIONAL SKIN CELLS. IN THIS STUDY, WE DISCOVERED THAT FIBROBLASTS ISOLATED FROM PSORIATIC SKIN LESIONS RETAIN AN ABNORMAL PHENOTYPE EVEN AFTER SEVERAL PASSAGES IN CULTURE. TRANSCRIPTOMIC PROFILING REVEALED THE UPREGULATION OF SEVERAL GENES, INCLUDING THE EXTRA DOMAIN A SPLICE VARIANT OF FIBRONECTIN AND ITGA4 IN PSORIATIC FIBROBLASTS. A PHENOTYPIC LIBRARY SCREENING OF SMALL-MOLECULE EPIGENETIC MODIFIER DRUGS REVEALED THAT SELECTIVE CBP/P300 INHIBITORS WERE ABLE TO RESCUE THE PSORIATIC FIBROBLAST PHENOTYPE, REDUCING THE EXPRESSION LEVELS OF EXTRA DOMAIN A SPLICE VARIANT OF FIBRONECTIN AND ITGA4. IN THE IMIQUIMOD-INDUCED MOUSE MODEL OF PSORIASIS-LIKE SKIN INFLAMMATION, SYSTEMIC TREATMENT WITH A485, A POTENT CBP/P300 BLOCKER, SIGNIFICANTLY REDUCED SKIN INFLAMMATION, IMMUNE CELL RECRUITMENT, AND INFLAMMATORY CYTOKINE PRODUCTION. OUR FINDINGS INDICATE THAT EPIGENETIC REPROGRAMMING MIGHT REPRESENT A NEW APPROACH FOR THE TREATMENT AND/OR PREVENTION OF RELAPSES OF PSORIASIS. 2023 2 4164 33 MEDIATORS OF CAPILLARY-TO-VENULE CONVERSION IN THE CHRONIC INFLAMMATORY SKIN DISEASE PSORIASIS. PSORIASIS IS A CHRONIC INFLAMMATORY SKIN DISEASE CHARACTERIZED BY EPIDERMAL HYPERPLASIA AND HYPERKERATOSIS, IMMUNE CELL INFILTRATION AND VASCULAR REMODELING. DESPITE THE EMERGING RECOGNITION OF VASCULAR NORMALIZATION AS A POTENTIAL STRATEGY FOR MANAGING PSORIASIS, AN IN-DEPTH DELINEATION OF THE REMODELED DERMAL VASCULATURE HAS BEEN MISSING. IN THIS STUDY, WE EXPLOITED 5' SINGLE-CELL RNA SEQUENCING TO INVESTIGATE THE TRANSCRIPTOMIC ALTERATIONS IN DIFFERENT SUBPOPULATIONS OF BLOOD VASCULAR AND LYMPHATIC ENDOTHELIAL CELLS DIRECTLY ISOLATED FROM PSORIATIC AND HEALTHY HUMAN SKIN. INDIVIDUAL SUBTYPES OF ENDOTHELIAL CELLS UNDERWENT SPECIFIC MOLECULAR REPATTERNING ASSOCIATED WITH CELL ADHESION AND EXTRACELLULAR MATRIX ORGANIZATION. BLOOD CAPILLARIES, IN PARTICULAR, SHOWED UPREGULATION OF THE MELANOMA CELL ADHESION MOLECULE AS WELL AS ITS BINDING PARTNERS AND ADOPTED POSTCAPILLARY VENULE?LIKE CHARACTERISTICS DURING CHRONIC INFLAMMATION THAT ARE MORE PERMISSIVE TO LEUKOCYTE TRANSMIGRATION. WE ALSO IDENTIFIED PSORIASIS-SPECIFIC INTERACTIONS BETWEEN CIS-REGULATORY ENHANCERS AND PROMOTERS FOR EACH ENDOTHELIAL CELL SUBTYPE, REVEALING THE DYSREGULATED GENE REGULATORY NETWORKS IN PSORIASIS. TOGETHER, OUR RESULTS PROVIDE MORE INSIGHTS INTO THE SPECIFIC TRANSCRIPTIONAL RESPONSES AND EPIGENETIC SIGNATURES OF ENDOTHELIAL CELLS LINING DIFFERENT VESSEL COMPARTMENTS IN CHRONIC SKIN INFLAMMATION. 2022 3 6057 22 THE DARK SIDE OF REGULATORY T CELLS IN PSORIASIS. PSORIASIS IS A HEREDITARY DISEASE ELICITED BY CHRONIC ACTIVATION OF CUTANEOUS T CELLS. DELINEATING THE MECHANISTIC INTERPLAY OF THE CELL SUBSETS INVOLVED IS KEY TO DEVELOPING THE NEXT GENERATION OF EFFECTIVE TREATMENTS. IN THIS ISSUE, BOVENSCHEN ET AL. REPORT THAT REGULATORY T CELLS MAINTAIN A FINE BALANCE BETWEEN THE TRANSCRIPTION FACTORS FOXP3 AND RORGAMMAT. IN PATIENTS WITH PSORIASIS, TREGS READILY TURN INTO IL-17-EXPRESSING CELLS, THUS POTENTIALLY PERPETUATING THE INFLAMMATORY PROCESS THAT CHARACTERIZES THE DISEASE. RESULTS DEMONSTRATING THAT THE HISTONE/PROTEIN DEACETYLATION INHIBITOR TRICHOSTATIN A CAN BLOCK THIS CONVERSION SUGGEST THAT AN EPIGENETIC MODIFICATION MAY UNDERLIE REGULATORY T-CELL PLASTICITY. 2011 4 5088 35 PIPERLONGUMINE REGULATES EPIGENETIC MODULATION AND ALLEVIATES PSORIASIS-LIKE SKIN INFLAMMATION VIA INHIBITION OF HYPERPROLIFERATION AND INFLAMMATION. PSORIASIS IS AN AUTOIMMUNE SKIN DISEASE, WHERE CHRONIC IMMUNE RESPONSES DUE TO EXAGGERATED CYTOKINE SIGNALING, ABNORMAL DIFFERENTIATION, AND EVASION OF KERATINOCYTES APOPTOSIS PLAYS A CRUCIAL ROLE IN MEDIATING ABNORMAL KERATINOCYTES HYPERPROLIFERATION. FROM THE THERAPEUTIC PERSPECTIVE, THE MOLECULES WITH STRONG ANTI-PROLIFERATIVE AND ANTI-INFLAMMATORY PROPERTIES COULD HAVE TREMENDOUS RELEVANCE. IN THIS STUDY, WE DEMONSTRATED THAT PIPERLONGUMINE (PPL) TREATMENT EFFECTIVELY ABROGATED THE HYPERPROLIFERATION AND DIFFERENTIATION OF KERATINOCYTES BY INDUCING ROS-MEDIATED LATE APOPTOSIS WITH LOSS OF MITOCHONDRIAL MEMBRANE POTENTIAL. BESIDES, THE ARREST OF CELL CYCLE WAS FOUND AT SUB-G1 PHASE AS A RESULT OF DNA FRAGMENTATION. MOLECULARLY, INHIBITION OF STAT3 AND AKT SIGNALING WAS OBSERVED WITH A DECREASE IN PROLIFERATIVE MARKERS SUCH AS PCNA, KI67, AND CYCLIN D1 ALONG WITH ANTI-APOPTOTIC BCL-2 PROTEIN EXPRESSION. KERATIN 17 IS A CRITICAL REGULATOR OF KERATINOCYTE DIFFERENTIATION, AND IT WAS FOUND TO BE DOWNREGULATED WITH PPL SIGNIFICANTLY. FURTHERMORE, PROMINENT ANTI-INFLAMMATORY EFFECTS WERE OBSERVED BY INHIBITION OF LIPOPOLYSACCHARIDE (LPS)/IMIQUIMOD (IMQ)-INDUCED P65 NF-KAPPAB SIGNALING CASCADE AND STRONGLY INHIBITED THE PRODUCTION OF CYTOKINE STORM INVOLVED IN PSORIASIS-LIKE SKIN INFLAMMATION, THUS LED TO THE RESTORATION OF NORMAL EPIDERMAL ARCHITECTURE WITH REDUCTION OF EPIDERMAL HYPERPLASIA AND SPLENOMEGALY. IN ADDITION, PPL EPIGENETICALLY INHIBITED HISTONE-MODIFYING ENZYMES, WHICH INCLUDE HISTONE DEACETYLASES (HDACS) OF CLASS I (HDAC1-4) AND CLASS II (HDAC6) EVALUATED BY IMMUNOBLOTTING AND HDAC ENZYME ASSAY KIT. IN ADDITION, OUR RESULTS SHOW THAT PPL EFFECTIVELY INHIBITS THE NUCLEAR TRANSLOCATION OF P65 AND A HISTONE MODULATOR HDAC3, THUS SEQUESTERED IN THE CYTOPLASM OF MACROPHAGES. FURTHERMORE, PPL EFFECTIVELY ENHANCED THE PROTEIN-PROTEIN INTERACTIONS OF HDAC3 AND P65 WITH IKAPPABALPHA, WHICH WAS DISRUPTED BY LPS STIMULATION AND WERE EVALUATED BY CO-IP AND MOLECULAR MODELING. COLLECTIVELY, OUR FINDINGS INDICATE THAT PIPERLONGUMINE MAY SERVE AS AN ANTI-PROLIFERATIVE AND ANTI-INFLAMMATORY AGENT AND COULD SERVE AS A POTENTIAL THERAPEUTIC OPTION IN TREATING PSORIASIS. 2020 5 2635 37 EPIGENOME-WIDE DNA METHYLATION REGULATES CARDINAL PATHOLOGICAL FEATURES OF PSORIASIS. BACKGROUND: PSORIASIS IS A CHRONIC INFLAMMATORY AUTOIMMUNE SKIN DISORDER. SEVERAL STUDIES SUGGESTED PSORIASIS TO BE A COMPLEX MULTIFACTORIAL DISEASE, BUT THE EXACT TRIGGERING FACTOR IS YET TO BE DETERMINED. EVIDENCES SUGGEST THAT IN ADDITION TO GENETIC FACTORS, EPIGENETIC REPROGRAMMING IS ALSO INVOLVED IN PSORIASIS DEVELOPMENT. MAJOR HISTOPATHOLOGICAL FEATURES, LIKE INCREASED PROLIFERATION AND ABNORMAL DIFFERENTIATION OF KERATINOCYTES, AND IMMUNE CELL INFILTRATIONS ARE CHARACTERISTIC MARKS OF PSORIATIC SKIN LESIONS. FOLLOWING THERAPY, HISTOPATHOLOGICAL FEATURES AS WELL AS ABERRANT DNA METHYLATION REVERSED TO NORMAL LEVELS. TO UNDERSTAND THE ROLE OF DNA METHYLATION IN REGULATING THESE CRUCIAL HISTOPATHOLOGIC FEATURES, WE INVESTIGATED THE GENOME-WIDE DNA METHYLATION PROFILE OF PSORIASIS PATIENTS WITH DIFFERENT HISTOPATHOLOGICAL FEATURES. RESULTS: GENOME-WIDE DNA METHYLATION PROFILING OF PSORIATIC AND ADJACENT NORMAL SKIN TISSUES IDENTIFIED SEVERAL NOVEL DIFFERENTIALLY METHYLATED REGIONS ASSOCIATED WITH PSORIASIS. DIFFERENTIALLY METHYLATED CPGS WERE SIGNIFICANTLY ENRICHED IN SEVERAL PSORIASIS SUSCEPTIBILITY (PSORS) REGIONS AND EPIGENETICALLY REGULATED THE EXPRESSION OF KEY PATHOGENIC GENES, EVEN WITH LOW-CPG PROMOTERS. TOP DIFFERENTIALLY METHYLATED GENES OVERLAPPED WITH PSORS REGIONS INCLUDING S100A9, SELENBP1, CARD14, KAZN AND PTPN22 SHOWED INVERSE CORRELATION BETWEEN METHYLATION AND GENE EXPRESSION. WE IDENTIFIED DIFFERENTIALLY METHYLATED GENES ASSOCIATED WITH CHARACTERISTIC HISTOPATHOLOGICAL FEATURES IN PSORIASIS. PSORIATIC SKIN WITH MUNRO'S MICROABSCESS, A DISTINCTIVE FEATURE IN PSORIASIS INCLUDING PARAKERATOSIS AND NEUTROPHIL ACCUMULATION AT THE STRATUM CORNEUM, WAS ENRICHED WITH DIFFERENTIALLY METHYLATED GENES INVOLVED IN NEUTROPHIL CHEMOTAXIS. RETE PEG ELONGATION AND FOCAL HYPERGRANULOSIS WERE ALSO ASSOCIATED WITH EPIGENETICALLY REGULATED GENES, SUPPORTING THE REVERSIBLE NATURE OF THESE CHARACTERISTIC FEATURES DURING REMISSION AND RELAPSE OF THE LESIONS. CONCLUSION: OUR STUDY, FOR THE FIRST TIME, INDICATED THE POSSIBLE INVOLVEMENT OF DNA METHYLATION IN REGULATING THE CARDINAL PATHOPHYSIOLOGICAL FEATURES IN PSORIASIS. COMMON GENES INVOLVED IN REGULATION OF THESE PATHOLOGIES MAY BE USED TO DEVELOP DRUGS FOR BETTER CLINICAL MANAGEMENT OF PSORIASIS. 2018 6 911 28 CHRONIC EXPOSURE TO TNF REPROGRAMS CELL SIGNALING PATHWAYS IN FIBROBLAST-LIKE SYNOVIOCYTES BY ESTABLISHING LONG-TERM INFLAMMATORY MEMORY. FIBROBLAST-LIKE SYNOVIOCYTES (FLS) PLAY A CRITICAL ROLE IN THE PATHOGENESIS OF RHEUMATOID ARTHRITIS (RA). CHRONIC INFLAMMATION INDUCES TRANSCRIPTOMIC AND EPIGENETIC MODIFICATIONS THAT IMPARTS A PERSISTENT CATABOLIC PHENOTYPE TO THE FLS, DESPITE THEIR DISSOCIATION FROM THE INFLAMMATORY ENVIRONMENT. WE ANALYZED HIGH THROUGHPUT GENE EXPRESSION AND CHROMATIN ACCESSIBILITY DATA FROM HUMAN AND MOUSE FLS FROM OUR AND OTHER STUDIES AVAILABLE ON PUBLIC REPOSITORIES, WITH THE GOAL OF IDENTIFYING THE PERSISTENTLY REPROGRAMMED SIGNALING PATHWAYS DRIVEN BY CHRONIC INFLAMMATION. WE FOUND THAT THE GENE EXPRESSION CHANGES INDUCED BY SHORT-TERM TUMOR NECROSIS FACTOR-ALPHA (TNF) TREATMENT WERE LARGELY SUSTAINED IN THE FLS EXPOSED TO CHRONIC INFLAMMATION. THESE CHANGES THAT INCLUDED BOTH ACTIVATION AND REPRESSION OF GENE EXPRESSION, WERE ACCOMPANIED BY THE REMODELING OF CHROMATIN ACCESSIBILITY. THE SUSTAINED ACTIVATED GENES (SAGS) INCLUDED ESTABLISHED PRO-INFLAMMATORY SIGNALING COMPONENTS KNOWN TO ACT AT MULTIPLE LEVELS OF NF-KAPPAB, STAT AND AP-1 SIGNALING CASCADES. INTERESTINGLY, THE SUSTAINED REPRESSED GENES (SRGS) INCLUDED CRITICAL MEDIATORS AND TARGETS OF THE BMP SIGNALING PATHWAY. WE THUS IDENTIFIED SUSTAINED REPRESSION OF BMP SIGNALING AS A UNIQUE CONSTITUENT OF THE LONG-TERM INFLAMMATORY MEMORY INDUCED BY CHRONIC INFLAMMATION. WE POSTULATE THAT SIMULTANEOUS TARGETING OF THESE ACTIVATED AND REPRESSED SIGNALING PATHWAYS MAY BE NECESSARY TO COMBAT RA PERSISTENCE. 2020 7 1618 26 DNA METHYLTRANSFERASE INHIBITORS INCREASE NOD-LIKE RECEPTOR ACTIVITY AND EXPRESSION IN A MONOCYTIC CELL LINE. BACKGROUND: THE INTRACELLULAR NOD-LIKE RECEPTOR (NLR) FAMILY OF PATHOGEN RECOGNITION RECEPTORS (PRRA) IS INVOLVED IN INITIATING THE INNATE IMMUNE RESPONSE OF WHICH NOD1 AND NOD2 ARE THE BEST-CHARACTERIZED MEMBERS. ABERRANT EXPRESSION OF NOD1 AND NOD2 HAS BEEN UNCOVERED IN A NUMBER OF CHRONIC INFLAMMATORY DISEASES, SUCH AS INFLAMMATORY BOWEL DISEASE AND RHEUMATOID ARTHRITIS. HOWEVER, THE MECHANISM UNDERLYING NOD1/NOD2 GENE EXPRESSION REGULATION IS STILL IN ITS INFANCY. EPIGENETIC MODIFICATIONS SUCH AS DNA METHYLATION AND HISTONE ACETYLATION REGULATE THE EXPRESSION OF GENES AND ALTERATIONS IN THEIR PATTERNS HAVE BEEN LINKED TO MANY INFLAMMATORY DISEASES. THIS STUDY INVESTIGATED WHETHER EPIGENETIC MODIFYING DRUGS AFFECT THE REGULATION OF NOD1/NOD2 ACTIVITY AND EXPRESSION. DNA METHYLTRANSFERASE INHIBITORS HAVE RECENTLY BEEN USED IN THE TREATMENT OF MYELODYSPLASTIC SYNDROME AND AS COMBINATION THERAPY IN CANCER BUT THE FULL EXTENT OF THEIR EFFECTS HAS NOT BEEN QUANTIFIED.METHODS: PHARMACOLOGICAL INHIBITION OF EPIGENETIC ENZYMES IN A HUMAN MONOCYTIC THP-1 CELL LINE WAS CARRIED OUT AND NOD1/NOD2 EXPRESSION AND PRO-INFLAMMATORY RESPONSES WERE QUANTIFIED.RESULTS: CELLS PRIMED WITH A DNA METHYLTRANSFERASE INHIBITOR (BUT NOT A HISTONE DEACETYLASE [HDAC] INHIBITOR) WERE FOUND TO BE CONSISTENTLY MORE RESPONSIVE TO NOD1/NOD2 STIMULATION AND HAD INCREASED BASAL EXPRESSION.CONCLUSION: THE NOVEL EXPERIMENTATION CARRIED OUT HERE SUGGESTS FOR THE FIRST TIME THAT NOD1/NOD2 RECEPTOR ACTIVITY AND EXPRESSION IN MONOCYTES ARE POSSIBLY REGULATED DIRECTLY BY DNA METHYLATION. 2022 8 2308 20 EPIGENETIC REGULATION OF CHEMOKINE (CC-MOTIF) LIGAND 2 IN INFLAMMATORY DISEASES. APPROPRIATE RESPONSES TO INFLAMMATION ARE CONDUCIVE TO PATHOGEN ELIMINATION AND TISSUE REPAIR, WHILE UNCONTROLLED INFLAMMATORY REACTIONS ARE LIKELY TO RESULT IN THE DAMAGE OF TISSUES. CHEMOKINE (CC-MOTIF) LIGAND 2 (CCL2) IS THE MAIN CHEMOKINE AND ACTIVATOR OF MONOCYTES, MACROPHAGES, AND NEUTROPHILS. CCL2 PLAYED A KEY ROLE IN AMPLIFYING AND ACCELERATING THE INFLAMMATORY CASCADE AND IS CLOSELY RELATED TO CHRONIC NON-CONTROLLABLE INFLAMMATION (CIRRHOSIS, NEUROPATHIC PAIN, INSULIN RESISTANCE, ATHEROSCLEROSIS, DEFORMING ARTHRITIS, ISCHEMIC INJURY, CANCER, ETC.). THE CRUCIAL REGULATORY ROLES OF CCL2 MAY PROVIDE POTENTIAL TARGETS FOR THE TREATMENT OF INFLAMMATORY DISEASES. THEREFORE, WE PRESENTED A REVIEW OF THE REGULATORY MECHANISMS OF CCL2. GENE EXPRESSION IS LARGELY AFFECTED BY THE STATE OF CHROMATIN. DIFFERENT EPIGENETIC MODIFICATIONS, INCLUDING DNA METHYLATION, POST-TRANSLATIONAL MODIFICATION OF HISTONES, HISTONE VARIANTS, ATP-DEPENDENT CHROMATIN REMODELLING, AND NON-CODING RNA, COULD AFFECT THE 'OPEN' OR 'CLOSED' STATE OF DNA, AND THEN SIGNIFICANTLY AFFECT THE EXPRESSION OF TARGET GENES. SINCE MOST EPIGENETIC MODIFICATIONS ARE PROVEN TO BE REVERSIBLE, TARGETING THE EPIGENETIC MECHANISMS OF CCL2 IS EXPECTED TO BE A PROMISING THERAPEUTIC STRATEGY FOR INFLAMMATORY DISEASES. THIS REVIEW FOCUSES ON THE EPIGENETIC REGULATION OF CCL2 IN INFLAMMATORY DISEASES. 2023 9 2389 22 EPIGENETIC REPOLARIZATION OF T LYMPHOCYTES FROM CHRONIC LYMPHOCYTIC LEUKEMIA PATIENTS USING 5-AZA-2'-DEOXYCYTIDINE. T CELL IMMUNE DYSFUNCTION HAS AN IMPORTANT ROLE IN THE PROFOUND IMMUNE SUPPRESSION THAT CHARACTERIZES CHRONIC LYMPHOCYTIC LEUKEMIA (CLL). IMPROPER POLARIZATION OF T CELLS HAS BEEN PROPOSED AS ONE OF THE MECHANISM INVOLVED. MOUNTING DATA IMPLICATES CHROMATIN REGULATION, NAMELY PROMOTER METHYLATION, IN THE PLASTICITY OF NAIVE HUMAN T CELLS. RECENT IN VITRO EVIDENCE INDICATES THAT THIS PLASTICITY MAY BE PHENOTYPICALLY ALTERED BY USING METHYLATION INHIBITORS WHICH ARE APPROVED FOR CLINICAL USE IN CERTAIN TYPES OF CANCER. THESE RESULTS BEG THE QUESTION: CAN THE INEFFECTIVE POLARIZATION OF T LYMPHOCYTES IN THE CONTEXT OF CLL BE EFFECTIVELY MODULATED USING METHYLATION INHIBITORS IN A SUSTAINABLE THERAPEUTIC FASHION? TO ANSWER THIS QUESTION OUR LABORATORY HAS STUDIED THE EFFECTS OF 5-AZA-2'-DEOXYCYTIDINE (5A2) IN HELPER AND CYTOTOXIC T LYMPHOCYTES FROM HEALTHY DONORS AND CLL PATIENTS IN WELL CHARACTERIZED MOLECULAR AND EPIGENETIC SIGNALING PATHWAYS INVOLVED IN EFFECTIVE POLARIZATION. MOREOVER, WE SOUGHT TO INVESTIGATE THE CONSEQUENCES OF METHYLATION INHIBITOR TREATMENT ON LYMPHOCYTE SURVIVAL, ACTIVATION INTENSITY, AND NAIVE CELL POLARIZATION. OUR DATA INDICATES THAT 5A2 TREATMENT CAN DEPOLARIZE TH2 CELLS TO EFFECTIVELY SECRETE INTERFERON GAMMA, SIGNAL VIA T-BET, AND ACHIEVE DEMETHYLATION OF CRITICAL TH1 SPECIFIC PROMOTERS. MOREOVER, WE DEMONSTRATE THAT 5A2 CAN FORCE TH1 POLARIZATION OF NAIVE T CELLS DESPITE A STRONG IL-4 STIMULI AND A LACK OF IL-12. IN CONCLUSION OUR DATA SEEKS TO DEFINE A MODALITY IN WHICH IMPROPER OR INEFFECTIVE T CELL POLARIZATION CAN BE ALTERED BY 5AZA AND COULD BE INCORPORATED IN FUTURE THERAPEUTIC INTERVENTIONS. 2011 10 3525 31 IL-1BETA, IL-8, AND MATRIX METALLOPROTEINASES-1, -2, AND -10 ARE ENRICHED UPON MONOCYTE-BREAST CANCER CELL COCULTIVATION IN A MATRIGEL-BASED THREE-DIMENSIONAL SYSTEM. BREAST CANCER REMAINS THE FIRST CANCER-RELATED CAUSE OF DEATH IN WOMEN WORLDWIDE, PARTICULARLY IN DEVELOPING COUNTRIES IN WHICH MOST CASES ARE DIAGNOSED IN LATE STAGES. ALTHOUGH MOST CANCER STUDIES ARE BASED IN THE GENETIC OR EPIGENETIC CHANGES OF THE TUMOR CELLS, IMMUNE CELLS WITHIN THE TUMOR STROMA OFTEN COOPERATE WITH CANCER PROGRESSION. PARTICULARLY, MONOCYTES ARE ATTRACTED TO THE TUMOR PRIMARY SITE IN WHICH THEY ARE DIFFERENTIATED INTO TUMOR-ASSOCIATED MACROPHAGES THAT FACILITATE TUMOR CELL INVASION AND METASTASIS. IN THIS STUDY, WE USED THREE-DIMENSIONAL CULTURES TO FORM ACINI-LIKE STRUCTURES TO ANALYZE THE INFLAMMATORY SECRETION PROFILE OF TUMOR CELLS INDIVIDUALLY OR IN CO-CULTURE WITH MONOCYTES. BREAST CANCER CELL LINES AND PRIMARY ISOLATES FROM EIGHT MEXICAN PATIENTS WITH BREAST CANCER WERE USED. WE FOUND HIGH LEVELS OF RANTES/CCL5, MCP-1/CCL2, AND G-CSF IN THE BREAST CANCER INDIVIDUAL CULTURES, SUPPORTING AN IMPORTANT RECRUITMENT CAPACITY OF MONOCYTES, BUT ALSO OF NEUTROPHILS. THE CO-CULTURES OF THE TUMOR CELLS AND MONOCYTES WERE SIGNIFICANTLY ENRICHED WITH THE POTENT PRO-INFLAMMATORY CYTOKINES INTERLEUKIN (IL)-1BETA AND IL-8, KNOWN TO SUPPORT MALIGNANT PROGRESSION. WE ALSO FOUND THAT THE INTERACTION OF TUMOR CELLS WITH MONOCYTES PROMOTED HIGH LEVELS OF MATRIX METALLOPROTEINASES (MMP)-1, MMP-2, AND MMP-10. OUR STUDY SUPPORTS THAT A KEY EVENT FOR MALIGNANT PROGRESSION IS THE RECRUITMENT OF DIFFERENT IMMUNE CELL POPULATIONS, WHICH HELP TO SUSTAIN AND ENHANCE A CHRONIC INFLAMMATORY MICROENVIRONMENT THAT HIGHLY FAVORS TUMOR MALIGNANCY. 2017 11 3193 32 HDAC INHIBITION REGULATES OXIDATIVE STRESS IN CD4(+)THELPER CELLS OF CHRONIC OBSTRUCTIVE PULMONARY DISEASE AND NON-SMALL CELL LUNG CANCER PATIENTS VIA MITOCHONDRIAL TRANSCRIPTION FACTOR A (MTTFA) MODULATING NF-KAPPAB/HIF1ALPHA AXIS. HISTONE DEACETYLASES (HDACS) PLAY A CRUCIAL ROLE IN THE EPIGENETIC REGULATION OF GENE EXPRESSION BY REMODELLING CHROMATIN. ISOENZYMES OF THE HDAC FAMILY EXHIBIT ABERRANT REGULATION IN A WIDE VARIETY OF CANCERS AS WELL AS SEVERAL INFLAMMATORY LUNG DISORDERS LIKE CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD). INHIBITION OF HDACS IS A POTENTIAL THERAPEUTIC STRATEGY THAT COULD BE USED TO REVERSE EPIGENETIC MODIFICATION. TRICHOSTATIN A (TSA), A POWERFUL HISTONE DEACETYLASE (HDAC) INHIBITOR, HAS ANTI-CANCER EFFECTS IN NUMEROUS CANCER TYPES. HOWEVER, IT IS NOT YET APPARENT HOW HDAC INHIBITORS AFFECT HUMAN NON-SMALL CELL LUNG CANCER CELLS (NSCLC) AND COPD. THIS STUDY AIMS TO INVESTIGATE TSA'S ROLE IN RESTORING MITOCHONDRIAL DYSFUNCTION AND ITS EFFECT ON HYPOXIA AND INFLAMMATION IN CD4(+)T CELLS OBTAINED FROM PATIENTS WITH COPD AND LUNG CANCER. AS A RESULT OF TREATMENT WITH TSA, THERE IS A REDUCTION IN THE EXPRESSION OF INFLAMMATORY CYTOKINES AND A DECREASED ENRICHMENT OF TRANSCRIPTIONAL FACTORS ASSOCIATED WITH INFLAMMATION AT VEGFA GENE LOCI. WE HAVE SEEN A SUBSTANTIAL DECREASE IN THE EXPRESSION OF NF-KAPPAB AND HIF1ALPHA, WHICH ARE THE CRITICAL MEDIATORS OF INFLAMMATION AND HYPOXIA, RESPECTIVELY. FOLLOWING TSA TREATMENT, MTTFA EXPRESSION WAS INCREASED, FACILITATING PATIENTS WITH COPD AND NSCLC IN THE RECOVERY OF THEIR DYSFUNCTIONAL MITOCHONDRIA. FURTHERMORE, WE HAVE DISCOVERED THAT TSA TREATMENT IN PATIENTS WITH COPD AND NSCLC MAY LEAD TO IMMUNOPROTECTIVE NESS BY INDUCING TH1NESS. OUR FINDING GIVES A NEW INSIGHT INTO THE EXISTING BODY OF KNOWLEDGE REGARDING TSA-BASED THERAPEUTIC METHODS AND HIGHLIGHTS THE NECESSITY OF EPIGENETIC THERAPY FOR THESE DEVASTATING LUNG DISORDERS. 2023 12 2228 27 EPIGENETIC MODIFICATIONS OF HISTONES IN PERIODONTAL DISEASE. PERIODONTITIS IS A CHRONIC INFECTIOUS DISEASE DRIVEN BY DYSBIOSIS, AN IMBALANCE BETWEEN COMMENSAL BACTERIA AND THE HOST ORGANISM. PERIODONTITIS IS A LEADING CAUSE OF TOOTH LOSS IN ADULTS AND OCCURS IN ABOUT 50% OF THE US POPULATION. IN ADDITION TO THE CLINICAL CHALLENGES ASSOCIATED WITH TREATING PERIODONTITIS, THE PROGRESSION AND CHRONIC NATURE OF THIS DISEASE SERIOUSLY AFFECT HUMAN HEALTH. EMERGING EVIDENCE SUGGESTS THAT PERIODONTITIS IS ASSOCIATED WITH MECHANISMS BEYOND BACTERIA-INDUCED PROTEIN AND TISSUE DEGRADATION. HERE, WE HYPOTHESIZE THAT BACTERIA ARE ABLE TO INDUCE EPIGENETIC MODIFICATIONS IN ORAL EPITHELIAL CELLS MEDIATED BY HISTONE MODIFICATIONS. IN THIS STUDY, WE FOUND THAT DYSBIOSIS IN VIVO LED TO EPIGENETIC MODIFICATIONS, INCLUDING ACETYLATION OF HISTONES AND DOWNREGULATION OF DNA METHYLTRANSFERASE 1. IN ADDITION, IN VITRO EXPOSURE OF ORAL EPITHELIAL CELLS TO LIPOPOLYSACCHARIDES RESULTED IN HISTONE MODIFICATIONS, ACTIVATION OF TRANSCRIPTIONAL COACTIVATORS, SUCH AS P300/CBP, AND ACCUMULATION OF NUCLEAR FACTOR-KAPPAB (NF-KAPPAB). GIVEN THAT ORAL EPITHELIAL CELLS ARE THE FIRST LINE OF DEFENSE FOR THE PERIODONTIUM AGAINST BACTERIA, WE ALSO EVALUATED WHETHER ACTIVATION OF PATHOGEN RECOGNITION RECEPTORS INDUCED HISTONE MODIFICATIONS. WE FOUND THAT ACTIVATION OF THE TOLL-LIKE RECEPTORS 1, 2, AND 4 AND THE NUCLEOTIDE-BINDING OLIGOMERIZATION DOMAIN PROTEIN 1 INDUCED HISTONE ACETYLATION IN ORAL EPITHELIAL CELLS. OUR FINDINGS CORROBORATE THE EMERGING CONCEPT THAT EPIGENETIC MODIFICATIONS PLAY A ROLE IN THE DEVELOPMENT OF PERIODONTITIS. 2016 13 5476 24 RESTORING T CELL TOLERANCE, EXPLORING THE POTENTIAL OF HISTONE DEACETYLASE INHIBITORS FOR THE TREATMENT OF JUVENILE IDIOPATHIC ARTHRITIS. JUVENILE IDIOPATHIC ARTHRITIS (JIA) IS CHARACTERIZED BY A LOSS OF IMMUNE TOLERANCE. HERE, THE BALANCE BETWEEN THE ACTIVITY OF EFFECTOR T (TEFF) CELLS AND REGULATORY T (TREG) CELLS IS DISTURBED RESULTING IN CHRONIC INFLAMMATION IN THE JOINTS. PRESENTLY, THERAPEUTIC STRATEGIES ARE PREDOMINANTLY AIMED AT SUPPRESSING IMMUNE ACTIVATION AND PRO-INFLAMMATORY EFFECTOR MECHANISMS, IGNORING THE OPPORTUNITY TO ALSO PROMOTE TOLERANCE BY BOOSTING THE REGULATORY SIDE OF THE IMMUNE BALANCE. HISTONE DEACETYLASES (HDACS) CAN DEACETYLATE BOTH HISTONE AND NON-HISTONE PROTEINS AND HAVE BEEN DEMONSTRATED TO MODULATE EPIGENETIC REGULATION AS WELL AS CELLULAR SIGNALING IN VARIOUS CELL TYPES. IMPORTANTLY, HDACS ARE POTENT REGULATORS OF BOTH TEFF CELL AND TREG CELL FUNCTION AND CAN THUS BE REGARDED AS ATTRACTIVE THERAPEUTIC TARGETS IN CHRONIC INFLAMMATORY ARTHRITIS. HDAC INHIBITORS (HDACI) HAVE PROVEN THERAPEUTIC POTENTIAL IN THE CANCER FIELD, AND ARE PRESENTLY BEING EXPLORED FOR THEIR POTENTIAL IN THE TREATMENT OF AUTOIMMUNE DISEASES. SPECIFIC HDACI HAVE ALREADY BEEN DEMONSTRATED TO REDUCE THE SECRETION OF PRO-INFLAMMATORY CYTOKINES BY TEFF CELLS, AND PROMOTE TREG NUMBERS AND SUPPRESSIVE CAPACITY IN VITRO AND IN VIVO. IN THIS REVIEW, WE OUTLINE THE ROLE OF THE DIFFERENT CLASSES OF HDACS IN BOTH TEFF CELL AND TREG CELL FUNCTION. FURTHERMORE, WE WILL REVIEW THE EFFECT OF DIFFERENT HDACI ON T CELL TOLERANCE AND EXPLORE THEIR POTENTIAL AS A THERAPEUTIC STRATEGY FOR THE TREATMENT OF OLIGOARTICULAR AND POLYARTICULAR JIA. 2019 14 2926 24 GENERATION OF AN EPIGENETIC SIGNATURE BY CHRONIC HYPOXIA IN PROSTATE CELLS. INCREASING LEVELS OF TISSUE HYPOXIA HAVE BEEN REPORTED AS A NATURAL FEATURE OF THE AGING PROSTATE GLAND AND MAY BE A RISK FACTOR FOR THE DEVELOPMENT OF PROSTATE CANCER. IN THIS STUDY, WE HAVE USED PWR-1E BENIGN PROSTATE EPITHELIAL CELLS AND AN EQUIVALENTLY AGED HYPOXIA-ADAPTED PWR-1E SUB-LINE TO IDENTIFY PHENOTYPIC AND EPIGENETIC CONSEQUENCES OF CHRONIC HYPOXIA IN PROSTATE CELLS. WE HAVE IDENTIFIED A SIGNIFICANTLY ALTERED CELLULAR PHENOTYPE IN RESPONSE TO CHRONIC HYPOXIA AS CHARACTERIZED BY INCREASED RECEPTOR-MEDIATED APOPTOTIC RESISTANCE, THE INDUCTION OF CELLULAR SENESCENCE, INCREASED INVASION AND THE INCREASED SECRETION OF IL-1 BETA, IL6, IL8 AND TNFALPHA CYTOKINES. IN ASSOCIATION WITH THESE PHENOTYPIC CHANGES AND THE ABSENCE OF HIF-1 ALPHA PROTEIN EXPRESSION, WE HAVE DEMONSTRATED SIGNIFICANT INCREASES IN GLOBAL LEVELS OF DNA METHYLATION AND H3K9 HISTONE ACETYLATION IN THESE CELLS, CONCOMITANT WITH THE INCREASED EXPRESSION OF DNA METHYLTRANSFERASE DMNT3B AND GENE-SPECIFIC CHANGES IN DNA METHYLATION AT KEY IMPRINTING LOCI. IN CONCLUSION, WE HAVE DEMONSTRATED A GENOME-WIDE ADJUSTMENT OF DNA METHYLATION AND HISTONE ACETYLATION UNDER CHRONIC HYPOXIC CONDITIONS IN THE PROSTATE. THESE EPIGENETIC SIGNATURES MAY REPRESENT AN ADDITIONAL MECHANISM TO PROMOTE AND MAINTAIN A HYPOXIC-ADAPTED CELLULAR PHENOTYPE WITH A POTENTIAL ROLE IN TUMOUR DEVELOPMENT. 2009 15 855 26 CHROMATIN ACCESSIBILITY LANDSCAPES OF IMMUNE CELLS IN RHEUMATOID ARTHRITIS NOMINATE MONOCYTES IN DISEASE PATHOGENESIS. BACKGROUND: RHEUMATOID ARTHRITIS (RA) IS A CHRONIC, SYSTEMIC AUTOIMMUNE DISEASE THAT INVOLVES A VARIETY OF CELL TYPES. HOWEVER, HOW THE EPIGENETIC DYSREGULATIONS OF PERIPHERAL IMMUNE CELLS CONTRIBUTE TO THE PATHOGENESIS OF RA STILL REMAINS LARGELY UNCLEAR. RESULTS: HERE, WE ANALYSED THE GENOME-WIDE ACTIVE DNA REGULATORY ELEMENTS OF FOUR MAJOR IMMUNE CELLS, NAMELY MONOCYTES, B CELLS, CD4(+) T CELLS AND CD8(+) T CELLS, IN PERIPHERAL BLOOD OF RA PATIENTS, OSTEOARTHRITIS (OA) PATIENTS AND HEALTHY DONORS USING ASSAY OF TRANSPOSASE ACCESSIBLE CHROMATIN WITH SEQUENCING (ATAC-SEQ). WE FOUND A STRONG RA-ASSOCIATED CHROMATIN DYSREGULATION SIGNATURE IN MONOCYTES, BUT NO OTHER EXAMINED CELL TYPES. MOREOVER, WE FOUND THAT SERUM C-REACTIVE PROTEIN (CRP) CAN INDUCE THE RA-ASSOCIATED CHROMATIN DYSREGULATION IN MONOCYTES VIA IN VITRO EXPERIMENTS. AND THE EXTENT OF THIS DYSREGULATION WAS REGULATED THROUGH THE TRANSCRIPTION FACTOR FRA2. CONCLUSIONS: TOGETHER, OUR STUDY REVEALED A CRP-INDUCED PATHOGENIC CHROMATIN DYSREGULATION SIGNATURE IN MONOCYTES FROM RA PATIENTS AND PREDICTED THE RESPONSIBLE SIGNALLING PATHWAY AS POTENTIAL THERAPEUTIC TARGETS FOR THE DISEASE. 2021 16 1594 31 DNA METHYLATION PROFILING REVEALS DIFFERENCES IN THE 3 HUMAN MONOCYTE SUBSETS AND IDENTIFIES UREMIA TO INDUCE DNA METHYLATION CHANGES DURING DIFFERENTIATION. HUMAN MONOCYTES ARE A HETEROGENEOUS CELL POPULATION CONSISTING OF 3 SUBSETS: CLASSICAL CD14++CD16-, INTERMEDIATE CD14++CD16+ AND NONCLASSICAL CD14+CD16++ MONOCYTES. VIA POORLY CHARACTERIZED MECHANISMS, INTERMEDIATE MONOCYTE COUNTS RISE IN CHRONIC INFLAMMATORY DISEASES, AMONG WHICH CHRONIC KIDNEY DISEASE IS OF PARTICULAR EPIDEMIOLOGIC IMPORTANCE. DNA METHYLATION IS A CENTRAL EPIGENETIC FEATURE THAT CONTROLS HEMATOPOIESIS. BY APPLYING NEXT-GENERATION METHYL-SEQUENCING WE NOW TESTED HOW FAR THE 3 MONOCYTE SUBSETS DIFFER IN THEIR DNA METHYLOME AND WHETHER UREMIA INDUCES DNA METHYLATION CHANGES IN DIFFERENTIATING MONOCYTES. WE FOUND THAT EACH MONOCYTE SUBSET DISPLAYS A UNIQUE PHENOTYPE WITH REGARDS TO DNA METHYLATION. GENES WITH DIFFERENTIALLY METHYLATED PROMOTER REGIONS IN INTERMEDIATE MONOCYTES WERE LINKED TO DISTINCT IMMUNOLOGICAL PROCESSES, WHICH IS IN LINE WITH RESULTS FROM RECENT GENE EXPRESSION ANALYSES. IN VITRO, UREMIA INDUCED DYSREGULATION OF DNA METHYLATION IN DIFFERENTIATING MONOCYTES, WHICH AFFECTED SEVERAL TRANSCRIPTION REGULATORS IMPORTANT FOR MONOCYTE DIFFERENTIATION (E.G., FLT3, HDAC1, MNT) AND LED TO ENHANCED GENERATION OF INTERMEDIATE MONOCYTES. AS POTENTIAL MEDIATOR, THE UREMIC TOXIN AND METHYLATION INHIBITOR S-ADENOSYLHOMOCYSTEINE INDUCED SHIFTS IN MONOCYTE SUBSETS IN VITRO, AND ASSOCIATED WITH MONOCYTE SUBSET COUNTS IN VIVO. OUR DATA SUPPORT THE CONCEPT OF MONOCYTE TRICHOTOMY AND THE DISTINCT ROLE OF INTERMEDIATE MONOCYTES IN HUMAN IMMUNITY. THE SHIFT IN MONOCYTE SUBSETS THAT OCCURS IN CHRONIC KIDNEY DISEASE, A PROINFLAMMATORY CONDITION OF SUBSTANTIAL EPIDEMIOLOGICAL IMPACT, MAY BE INDUCED BY ACCUMULATION OF UREMIC TOXINS THAT MEDIATE EPIGENETIC DYSREGULATION. 2016 17 5114 30 PORPHYROMONAS GINGIVALIS LIPOPOLYSACCHARIDE STIMULATION IN HUMAN PERIODONTAL LIGAMENT STEM CELLS: ROLE OF EPIGENETIC MODIFICATIONS TO THE INFLAMMATION. PERIODONTITIS IS A CHRONIC ORAL INFLAMMATORY DISEASE PRODUCED BY BACTERIA. GINGIVAL RETRACTION AND BONE AND CONNECTIVE TISSUES RESORPTION ARE THE HALLMARKS OF THIS DISEASE. CHRONIC PERIODONTITIS MAY CONTRIBUTE TO THE RISK OF ONSET OR PROGRESSION OF NEUROINFLAMMATORY PATHOLOGICAL CONDITIONS, SUCH AS ALZHEIMER'S DISEASE. THE MAIN GOAL OF THE PRESENT STUDY WAS TO INVESTIGATE IF THE ROLE OF EPIGENETIC MODULATIONS IS INVOLVED IN PERIODONTITIS USING HUMAN PERIODONTAL LIGAMENT STEM CELLS (HPDLSCS) AS AN IN VITRO MODEL SYSTEM. HPDLSCS WERE TREATED WITH LIPOPOLYSACCHARIDE OF PORPHYROMONAS GINGIVALIS AND THE EXPRESSION OF PROTEINS ASSOCIATED WITH DNA METHYLATION AND HISTONE ACETYLATION, SUCH AS DNMT1 AND P300, RESPECTIVELY, AND INFLAMMATORY TRANSCRIPTION FACTOR NF-KB, WERE EXAMINED. IMMUNOFLUORESCENCE, WESTERN BLOT AND NEXT GENERATION SEQUENCING RESULTS DEMONSTRATED THAT P. GINGIVALIS LIPOPOLYSACCHARIDE SIGNIFICANTLY REDUCED DNA METHYLASE DNMT1, WHILE IT MARKEDLY UPREGULATED THE LEVEL OF HISTONE ACETYLTRANSFERASE P300 AND NF-KB IN HPDLSCS. OUR RESULTS SHOWED THAT P. GINGIVALIS LIPOPOLYSACCHARIDE MARKEDLY REGULATE THE GENES INVOLVED IN EPIGENETIC MECHANISM, WHICH MAY RESULT IN INFLAMMATION INDUCTION. WE PROPOSE THAT P. GINGIVALIS LIPOPOLYSACCHARIDE-TREATED HPDLSCS COULD BE A POTENTIAL IN VITRO MODEL SYSTEM TO STUDY EPIGENETICS MODULATIONS ASSOCIATED WITH PERIODONTITIS, WHICH MIGHT BE HELPFUL TO IDENTIFY NOVEL BIOMARKERS LINKED TO THIS ORAL INFLAMMATORY DISEASE. 2017 18 3527 22 IL-6 ENHANCES THE NUCLEAR TRANSLOCATION OF DNA CYTOSINE-5-METHYLTRANSFERASE 1 (DNMT1) VIA PHOSPHORYLATION OF THE NUCLEAR LOCALIZATION SEQUENCE BY THE AKT KINASE. THE EPIGENETIC PROGRAMMING OF GENOMIC DNA IS ACCOMPLISHED, IN PART, BY SEVERAL DNA CYTOSINE-5-METHYLTRANSFERASES THAT ACT BY COVALENTLY MODIFYING CYTOSINES WITH THE ADDITION OF A METHYL GROUP. THIS COVALENT MODIFICATION IS MAINTAINED BY THE DNA CYTOSINE-5-METHYLTRANSFERASE-1 ENZYME (DNMT1), WHICH IS CAPABLE OF ACTING IN CONCERT WITH OTHER SIMILAR ENZYMES TO SILENCE IMPORTANT TUMOR SUPPRESSOR GENES. IL-6 IS A MULTIFUNCTIONAL MEDIATOR OF INFLAMMATION, ACTING THROUGH SEVERAL MAJOR SIGNALING CASCADES, INCLUDING THE PHOSPHATIDYLINOSITOL-3-KINASE PATHWAY (PI-3-K), WHICH ACTIVATES PROTEIN KINASE B (AKT/PKB) DOWNSTREAM. HERE, WE SHOW THAT THE SUBCELLULAR LOCALIZATION OF DNMT1 CAN BE ALTERED BY THE ADDITION OF IL-6, INCREASING THE RATE OF NUCLEAR TRANSLOCATION OF THE ENZYME FROM THE CYTOSOLIC COMPARTMENT. THE MECHANISM OF NUCLEAR TRANSLOCATION OF DNMT1 IS GREATLY ENHANCED BY PHOSPHORYLATION OF THE DNMT1 NUCLEAR LOCALIZATION SIGNAL (NLS) BY PKB/AKT KINASE. MUTAGENIC ALTERATION OF THE TWO AKT TARGET AMINO ACIDS WITHIN THE NLS RESULTS IN A MAJOR LOSS OF DNMT1 NUCLEAR TRANSLOCATION, WHILE THE CREATION OF A "PHOSPHO-MIMIC" AMINO ACID (MUTATION TO ACIDIC RESIDUES) RESTORES THIS COMPARTMENTATION ABILITY. THESE OBSERVATIONS SUGGEST AN INTERESTING HYPOTHESIS REGARDING HOW MEDIATORS OF CHRONIC INFLAMMATION MAY DISTURB THE DELICATE BALANCE OF CELLULAR COMPARTMENTALIZATION OF IMPORTANT PROTEINS, AND REVEALS A POTENTIAL MECHANISM FOR THE INDUCTION OR ENHANCEMENT OF TUMOR GROWTH VIA ALTERATION OF THE COMPONENTS INVOLVED IN THE EPIGENETIC PROGRAMMING OF A CELL. 2007 19 827 31 CHARACTERIZATION OF LONG NON-CODING RNAS IN SYSTEMIC SCLEROSIS MONOCYTES: A POTENTIAL ROLE FOR PSMB8-AS1 IN ALTERED CYTOKINE SECRETION. SYSTEMIC SCLEROSIS (SSC) IS A CHRONIC AUTOIMMUNE DISEASE MAINLY AFFECTING THE CONNECTIVE TISSUE. IN SSC PATIENTS, MONOCYTES ARE INCREASED IN CIRCULATION, INFILTRATE AFFECTED TISSUES, AND SHOW A PRO-INFLAMMATORY ACTIVATION STATUS, INCLUDING THE SO-CALLED INTERFERON (IFN) SIGNATURE. WE PREVIOUSLY DEMONSTRATED THAT THE DYSREGULATION OF THE IFN RESPONSE IN SSC MONOCYTES IS SUSTAINED BY ALTERED EPIGENETIC FACTORS AS WELL AS BY UPREGULATION OF THE LONG NON-CODING RNA (LNCRNA) NRIR. CONSIDERING THE ENORMOUSLY DIVERSE MOLECULAR FUNCTIONS OF LNCRNAS IN IMMUNE REGULATION, THE PRESENT STUDY INVESTIGATED THE GENOME-WIDE PROFILE OF LNCRNAS IN SSC MONOCYTES, WITH THE AIM TO FURTHER UNRAVEL THEIR POSSIBLE ROLE IN MONOCYTE DYSREGULATION AND DISEASE PATHOGENESIS. TRANSCRIPTOMIC DATA FROM TWO INDEPENDENT COHORTS OF SSC PATIENTS IDENTIFIED 886 LNCRNAS WITH AN ALTERED EXPRESSION IN SSC MONOCYTES. DIFFERENTIALLY EXPRESSED LNCRNAS WERE CORRELATED WITH NEIGHBORING PROTEIN CODING GENES IMPLICATED IN THE REGULATION OF IFN RESPONSES AND APOPTOTIC SIGNALING IN SSC MONOCYTES. IN PARALLEL, GENE CO-EXPRESSION NETWORK ANALYSIS IDENTIFIED THE LNCRNA PSMB8-AS1 AS A TOP-RANKING HUB GENE IN CO-EXPRESSION MODULES IMPLICATED IN CELL ACTIVATION AND RESPONSE TO VIRAL AND EXTERNAL STIMULI. FUNCTIONAL CHARACTERIZATION OF PSMB8-AS1 IN MONOCYTES DEMONSTRATED THAT THIS LNCRNA IS INVOLVED IN THE SECRETION OF IL-6 AND TNFALPHA, TWO PIVOTAL PRO-INFLAMMATORY CYTOKINES ALTERED IN THE CIRCULATION OF SSC PATIENTS AND ASSOCIATED WITH FIBROSIS AND DISEASE SEVERITY. COLLECTIVELY, OUR DATA SHOWED THAT LNCRNAS ARE LINKED TO MONOCYTE DYSREGULATION IN SSC, AND HIGHLIGHT THEIR POTENTIAL CONTRIBUTION TO DISEASE PATHOGENESIS. 2021 20 5292 25 PROSTATIC INFLAMMATION ENHANCES BASAL-TO-LUMINAL DIFFERENTIATION AND ACCELERATES INITIATION OF PROSTATE CANCER WITH A BASAL CELL ORIGIN. CHRONIC INFLAMMATION HAS BEEN SHOWN TO PROMOTE THE INITIATION AND PROGRESSION OF DIVERSE MALIGNANCIES BY INDUCING GENETIC AND EPIGENETIC ALTERATIONS. IN THIS STUDY, WE INVESTIGATE AN ALTERNATIVE MECHANISM THROUGH WHICH INFLAMMATION PROMOTES THE INITIATION OF PROSTATE CANCER. ADULT MURINE PROSTATE EPITHELIA ARE COMPOSED PREDOMINANTLY OF BASAL AND LUMINAL CELLS. PREVIOUS STUDIES REVEALED THAT THE TWO LINEAGES ARE LARGELY SELF-SUSTAINED WHEN RESIDING IN THEIR NATIVE MICROENVIRONMENT. TO INTERROGATE WHETHER TISSUE INFLAMMATION ALTERS THE DIFFERENTIATION PROGRAM OF BASAL CELLS, WE CONDUCTED LINEAGE TRACING OF BASAL CELLS USING A K14-CREER;MTMG MODEL IN CONCERT WITH A MURINE MODEL OF PROSTATITIS INDUCED BY INFECTION FROM THE UROPATHOGENIC BACTERIA CP9. WE SHOW THAT ACUTE PROSTATITIS CAUSES TISSUE DAMAGE AND CREATES A TISSUE MICROENVIRONMENT THAT INDUCES THE DIFFERENTIATION OF BASAL CELLS INTO LUMINAL CELLS, AN ALTERATION THAT RARELY OCCURS UNDER NORMAL PHYSIOLOGICAL CONDITIONS. PREVIOUSLY WE SHOWED THAT A MOUSE MODEL WITH PROSTATE BASAL CELL-SPECIFIC DELETION OF PHOSPHATASE AND TENSIN HOMOLOG (K14-CREER;PTEN(FL/FL)) DEVELOPS PROSTATE CANCER WITH A LONG LATENCY, BECAUSE DISEASE INITIATION IN THIS MODEL REQUIRES AND IS LIMITED BY THE DIFFERENTIATION OF TRANSFORMATION-RESISTANT BASAL CELLS INTO TRANSFORMATION-COMPETENT LUMINAL CELLS. HERE, WE SHOW THAT CP9-INDUCED PROSTATITIS SIGNIFICANTLY ACCELERATES THE INITIATION OF PROSTATIC INTRAEPITHELIAL NEOPLASIA IN THIS MODEL. OUR RESULTS DEMONSTRATE THAT INFLAMMATION RESULTS IN A TISSUE MICROENVIRONMENT THAT ALTERS THE NORMAL PROSTATE EPITHELIAL CELL DIFFERENTIATION PROGRAM AND THAT THROUGH THIS CELLULAR PROCESS INFLAMMATION ACCELERATES THE INITIATION OF PROSTATE CANCER WITH A BASAL CELL ORIGIN. 2014