1 2810 129 FGF23 AND FETUIN-A INTERACTION IN THE LIVER AND IN THE CIRCULATION. RECENTLY IT HAS BEEN DEMONSTRATED THAT FETUIN-A, AN ANTI-INFLAMMATORY PROTEIN SYNTHESIZED BY THE LIVER, IS PRODUCED ALSO IN BONE BY AN FGF23-REGULATED PATHWAY. FGF23 HAS BEEN ALSO DEMONSTRATED TO INDUCE INFLAMMATORY CYTOKINE PRODUCTION IN THE LIVER. THIS STUDY AIMED TO EXPLORE IF FGF23 PLAYS A ROLE IN THE FETUIN-A PRODUCTION IN THE LIVER CELLS TOO AND THE POSSIBLE RELATIONSHIPS WITH FGF23 PRO-INFLAMMATORY EFFECTS. FGF23 AND FETUIN-A WERE STUDIED IN LIVER, KIDNEY AND IN PLASMA WITH IMMUNOCHEMISTRY, IMMUNOPRECIPITATION, WESTERN BLOT, CHROMATIN IMMUNOPRECIPITATION, DUOLINK, ELISA, QRTPCR METHODOLOGY. FGF23 IS PRODUCED, BUT NOT SECRETED BY THE LIVER CELLS. IN HEPATOCYTES AND CIRCULATION, FGF23 WAS PRESENT ONLY STRICTLY LINKED TO FETUIN-A, WHILE FETUIN-A WAS FOUND ALSO IN UNBOUNDED FORM. NO LINK WAS OBSERVED IN THE KIDNEY. FGF23 UP TO 600 PG/ML STIMULATES, WHILE, AT HIGHER CONCENTRATIONS, REDUCES FETUIN-A EXPRESSION. NOTABLY, OVERALL THE RANGE OF CONCENTRATIONS, FGF23 STIMULATES FETUIN-A PROMOTER, TNFALPHA AND IL6 EXPRESSION. IN THE NUCLEUS, FGF23 SEEMS TO ACT AS A DIRECT TRANSCRIPTION FACTOR OF FETUIN-A PROMOTER. THESE RESULTS SUGGEST THAT FGF23 PLAYED A DIRECT REGULATORY ROLE IN FETUIN-A EXPRESSION IN LIVER CELLS WITH A BIPHASIC EFFECT: FETUIN-A PROGRESSIVELY INCREASES WHEN FGF23 INCREASES UP TO 400-600 PG/ML, AND DECLINES AT HIGHER FGF23 CONCENTRATIONS. THESE RESULTS LEAD US TO HYPOTHESIZE: A) A POSSIBLE EPIGENETIC POST-TRANSCRIPTIONAL REGULATION; B) A POSSIBLE COUNTER-REGULATORY EFFECT OF FGF23 INDUCED INFLAMMATORY CYTOKINES (TNFALPHA/ NF-KAPPAB MECHANISM). THIS STUDY COULD ADD AN ADDITIONAL KEY FOR THE INTERPRETATION OF THE POSSIBLE MECHANISMS LINKING FGF23, FETUIN-A AND INFLAMMATION IN CKD PATIENTS AND SUGGESTS A ROLE FOR FGF23 AS TRANSCRIPTION FACTOR. 2018 2 3437 32 HYPERGLYCEMIC MICROENVIRONMENT COMPROMISES THE HOMEOSTASIS OF COMMUNICATION BETWEEN THE BONE-BRAIN AXIS BY THE EPIGENETIC REPRESSION OF THE OSTEOCALCIN RECEPTOR, GPR158 IN THE HIPPOCAMPUS. DIABETES MELLITUS (DM) IS A CHRONIC METABOLIC DISEASE, MAINLY CHARACTERIZED BY INCREASED BLOOD GLUCOSE AND INSULIN DYSFUNCTION. IN RESPONSE TO THE PERSISTENT SYSTEMIC HYPERGLYCEMIC STATE, NUMEROUS METABOLIC AND PHYSIOLOGICAL COMPLICATIONS HAVE ALREADY BEEN WELL CHARACTERIZED. HOWEVER, ITS RELATIONSHIP TO BONE FRAGILITY, COGNITIVE DEFICITS AND INCREASED RISK OF DEMENTIA STILL NEEDS TO BE BETTER UNDERSTOOD. THE IMPACT OF CHRONIC HYPERGLYCEMIA ON BONE PHYSIOLOGY AND ARCHITECTURE WAS ASSESSED IN A MODEL OF CHRONIC HYPERGLYCEMIA INDUCED BY A SINGLE INTRAPERITONEAL ADMINISTRATION OF STREPTOZOTOCIN (STZ; 55 MG/KG) IN WISTAR RATS. IN ADDITION, THE BONE-TO-BRAIN COMMUNICATION WAS INVESTIGATED BY ANALYZING THE GENE EXPRESSION AND METHYLATION STATUS OF GENES THAT ENCODE THE MAIN OSTEOKINES RELEASED BY THE BONE [FGF23 (FIBROBLAST GROWTH FACTOR 23), BGLAP (BONE GAMMA-CARBOXYGLUTAMATE PROTEIN) AND LCN2 (LIPOCALIN 2) AND THEIR RECEPTORS IN BOTH, THE BONE AND THE BRAIN [FGFR1 (FIBROBLAST GROWTH FACTOR RECEPTOR 1), GPR6A (G-PROTEIN COUPLED RECEPTOR FAMILY C GROUP 6 MEMBER A), GPR158 (G PROTEIN-COUPLED RECEPTOR 158) AND SLC22A17 (SOLUTE CARRIER FAMILY 22 MEMBER 17)]. IT WAS OBSERVED THAT CHRONIC HYPERGLYCEMIA NEGATIVELY IMPACTED ON BONE BIOLOGY AND COMPROMISED THE BALANCE OF THE BONE-BRAIN ENDOCRINE AXIS. ULTRASTRUCTURAL DISORGANIZATION WAS ACCOMPANIED BY GLOBAL DNA HYPOMETHYLATION AND CHANGES IN GENE EXPRESSION OF DNA-MODIFYING ENZYMES THAT WERE ACCOMPANIED BY CHANGES IN THE METHYLATION STATUS OF THE OSTEOKINE PROMOTER REGION BGLAP AND LCN2 (LIPOCALIN 2) IN THE FEMUR. ADDITIONALLY, THE CHRONIC HYPERGLYCEMIC STATE WAS ACCOMPANIED BY MODULATION OF GENE EXPRESSION OF THE OSTEOKINES FGF23 (FIBROBLAST GROWTH FACTOR 23), BGLAP (BONE GAMMA-CARBOXYGLUTAMATE PROTEIN) AND LCN2 (LIPOCALIN 2) IN THE DIFFERENT BRAIN REGIONS. HOWEVER, TRANSCRIPTIONAL REGULATION MEDIATED BY DNA METHYLATION WAS OBSERVED ONLY FOR THE OSTEOKINE RECEPTORS, FGFR1(FIBROBLAST GROWTH FACTOR RECEPTOR 1) IN THE STRIATUM AND GPR158 (G PROTEIN-COUPLED RECEPTOR 158) IN THE HIPPOCAMPUS. THIS IS A PIONEER STUDY DEMONSTRATING THAT THE CHRONIC HYPERGLYCEMIC STATE COMPROMISES THE CROSSTALK BETWEEN BONE TISSUE AND THE BRAIN, MAINLY AFFECTING THE HIPPOCAMPUS, THROUGH TRANSCRIPTIONAL SILENCING OF THE BGLAP RECEPTOR BY HYPERMETHYLATION OF GPR158 GENE. 2023 3 3128 38 GIPC-REGULATED IGFBP-3 PROMOTES HSC MIGRATION IN VITRO AND PORTAL HYPERTENSION IN VIVO THROUGH A BETA1-INTEGRIN PATHWAY. BACKGROUND & AIMS: TRANSFORMING GROWTH FACTOR (TGF-BETA)-INDUCED ACTIVATION OF QUIESCENT HEPATIC STELLATE CELLS (HSCS) AND THEIR TRANSFORMATION TO MYOFIBROBLASTS IS A KEY EVENT IN LIVER FIBROSIS AND PORTAL HYPERTENSION. GIPC (ALSO REFERRED TO AS SYNECTIN) IS A DOWNSTREAM SIGNAL ACTIVATION MOLECULE OF TGF-BETA AND OTHER RECEPTORS. IN THIS STUDY, WE SOUGHT TO IDENTIFY NOVEL GENES TARGETED BY TGF-BETA AND GIPC AND ELUCIDATE IF AND HOW THEY MAY CONTRIBUTE TO LIVER FIBROSIS. METHODS: WE PERFORMED SEQUENTIAL MESSENGER RNA SEQUENCING ANALYSIS ON TGF-BETA-STIMULATED HSCS AND THEN ON TGF-BETA-STIMULATED HSCS IN THE PRESENCE AND ABSENCE OF GIPC ALSO REFERRED TO AS SYNECTIN (GIPC) KNOCKDOWN. INSULIN-LIKE GROWTH FACTOR BINDING PROTEIN-3 (IGFBP-3) TRANSPORT PROTEIN EMERGED AS A TOP ACTIVATION TARGET OF BOTH TGF-BETA AND GIPC. QUANTITATIVE POLYMERASE CHAIN REACTION, ENZYME-LINKED IMMUNOSORBENT ASSAY, TARGETED CHROMATIN IMMUNOPRECIPITATION, AND WESTERN BLOT ANALYSIS WERE DONE FOR FURTHER CONFIRMATION. RESULTS: IGFBP-3, AN INSULIN GROWTH FACTOR TRANSPORT PROTEIN, EMERGED AS A TOP ACTIVATION TARGET OF BOTH TGF-BETA AND GIPC, WHICH WAS CONFIRMED BY QUANTITATIVE POLYMERASE CHAIN REACTION, ENZYME-LINKED IMMUNOSORBENT ASSAY, AND WESTERN BLOT ANALYSIS. TARGETED CHROMATIN IMMUNOPRECIPITATION SHOWED THAT GIPC INCREASES THE HISTONE 3 LYSINE 27 (H3K27) ACETYLATION ACTIVATING MARK AND CONCURRENTLY DECREASES THE H3K27 INHIBITORY TRIMETHYLATION (H3K27M3) MARK, PROVIDING AN EPIGENETIC CORRELATE TO THE GENE REGULATION CHANGES. IN VIVO, GLOBAL KNOCKOUT OF IGFBP-3 MICE RESULTED IN ATTENUATION OF HSC ACTIVATION MARKERS AND ATTENUATION OF PORTAL PRESSURE IN RESPONSE TO CHRONIC LIVER INJURY MODELS. ANALYSIS OF SERUM LEVELS FROM CIRRHOTIC PATIENTS ALSO SHOWED AN IGFBP-3 INCREASE OF MORE THAN 2-FOLD COMPARED WITH HEALTHY CONTROLS. FINALLY, IN VITRO MECHANISM STUDIES SHOWED THAT IGFBP-3 PROMOTES HSC MIGRATION THROUGH INTEGRIN-DEPENDENT PHOSPHORYLATION OF PROTEIN KINASE B. CONCLUSIONS: TGF-BETA UP-REGULATES IGFBP-3 THROUGH GIPC, LEADING TO INCREASED HSC MIGRATION IN VITRO AND PROMOTES PORTAL HYPERTENSION IN VIVO. THESE STUDIES SUPPORT THE ROLE OF IGFBP-3 AS A POTENTIAL PATHOPHYSIOLOGIC TARGET OR BIOMARKER IN CHRONIC LIVER DISEASE. 2020 4 3049 30 GENOME-WIDE ANALYSIS REVEALS ZINC TRANSPORTER ZIP9 REGULATED BY DNA METHYLATION PROMOTES RADIATION-INDUCED SKIN FIBROSIS VIA THE TGF-BETA SIGNALING PATHWAY. RADIATION-INDUCED SKIN FIBROSIS IS A DETRIMENTAL AND CHRONIC DISORDER THAT OCCURS AFTER RADIATION EXPOSURE. DNA METHYLATION HAS BEEN CHARACTERIZED AS AN IMPORTANT REGULATORY MECHANISM OF MULTIPLE PATHOLOGICAL PROCESSES. IN THIS STUDY, WE COMPARED THE GENOME-WIDE DNA METHYLATION STATUS IN RADIATION-INDUCED FIBROTIC SKIN AND ADJACENT NORMAL TISSUES OF RATS BY METHYLATED DNA IMMUNOPRECIPITATION SEQUENCING. RADIATION-INDUCED FIBROTIC SKIN SHOWED DIFFERENTIALLY METHYLATED REGIONS ASSOCIATED WITH 3,650 PROTEIN-CODING GENES, 72 MICRORNAS, 5,836 LONG NONCODING RNAS AND 3 PIWI-INTERACTING RNAS. BY INTEGRATING THE MRNA AND METHYLATION PROFILES, THE ZINC TRANSPORTER SLC39A9/ZIP9 WAS INVESTIGATED IN GREATER DETAIL. THE PROTEIN LEVEL OF ZIP9 WAS INCREASED IN IRRADIATED SKIN TISSUES OF HUMANS, MONKEYS, AND RATS, ESPECIALLY IN RADIOGENIC FIBROTIC SKIN TISSUES. RADIATION INDUCED THE DEMETHYLATION OF A CPG DINUCLEOTIDE IN EXON 1 OF ZIP9 THAT RESULTED IN RECRUITMENT OF THE TRANSCRIPTIONAL FACTOR SP1 AND INCREASED ZIP9 EXPRESSION. OVEREXPRESSION OF ZIP9 RESULTED IN ACTIVATION OF THE PROFIBROTIC TRANSFORMING GROWTH FACTOR-BETA SIGNALING PATHWAY THROUGH PROTEIN KINASE B IN HUMAN FIBROBLASTS. IN ADDITION, RADIATION-INDUCED SKIN FIBROSIS WAS ASSOCIATED WITH INCREASED ZINC ACCUMULATION. THE ZINC CHELATOR N,N,N',N'-TETRAKIS(2-PYRIDYLMETHYL)-1,2-ETHYLENEDIAMINE ABROGATED ZIP9-INDUCED ACTIVATION OF THE TRANSFORMING GROWTH FACTOR-BETA SIGNALING PATHWAY AND ATTENUATED RADIATION-INDUCED SKIN FIBROSIS IN A RAT MODEL. IN SUMMARY, OUR FINDINGS ILLUSTRATE EPIGENETIC REGULATION OF ZIP9 AND ITS CRITICAL ROLE IN PROMOTING RADIATION-INDUCED SKIN FIBROSIS. 2020 5 6294 32 THE PROINFLAMMATORY CYTOKINE TNFALPHA INDUCES DNA DEMETHYLATION-DEPENDENT AND -INDEPENDENT ACTIVATION OF INTERLEUKIN-32 EXPRESSION. IL-32 IS A CYTOKINE INVOLVED IN PROINFLAMMATORY IMMUNE RESPONSES TO BACTERIAL AND VIRAL INFECTIONS. HOWEVER, THE ROLE OF EPIGENETIC EVENTS IN THE REGULATION OF IL-32 GENE EXPRESSION IS UNDERSTUDIED. HERE WE SHOW THAT IL-32 IS REPRESSED BY DNA METHYLATION IN HEK293 CELLS. USING CHIP SEQUENCING, LOCUS-SPECIFIC METHYLATION ANALYSIS, CRISPR/CAS9-MEDIATED GENOME EDITING, AND RT-QPCR (QUANTITATIVE RT-PCR) AND IMMUNOBLOT ASSAYS, WE FOUND THAT SHORT-TERM TREATMENT (A FEW HOURS) WITH THE PROINFLAMMATORY CYTOKINE TUMOR NECROSIS FACTOR ALPHA (TNFALPHA) ACTIVATES IL-32 IN A DNA DEMETHYLATION-INDEPENDENT MANNER. IN CONTRAST, PROLONGED TNFALPHA TREATMENT (SEVERAL DAYS) INDUCED DNA DEMETHYLATION AT THE PROMOTER AND A CPG ISLAND IN THE IL-32 GENE IN A TET (TEN-ELEVEN TRANSLOCATION) FAMILY ENZYME- AND NF-KAPPAB-DEPENDENT MANNER. NOTABLY, THE HYPOMETHYLATION STATUS OF TRANSCRIPTIONAL REGULATORY ELEMENTS IN IL-32 WAS MAINTAINED FOR A LONG TIME (SEVERAL WEEKS), CAUSING ELEVATED IL-32 EXPRESSION EVEN IN THE ABSENCE OF TNFALPHA. CONSIDERING THAT IL-32 CAN, IN TURN, INDUCE TNFALPHA EXPRESSION, WE SPECULATE THAT SUCH FEEDFORWARD EVENTS MAY CONTRIBUTE TO THE TRANSITION FROM AN ACUTE INFLAMMATORY RESPONSE TO CHRONIC INFLAMMATION. 2019 6 1335 33 DERMAL FIBROBLASTS CULTURED FROM DONORS WITH TYPE 2 DIABETES MELLITUS RETAIN AN EPIGENETIC MEMORY ASSOCIATED WITH POOR WOUND HEALING RESPONSES. THE PREVALENCE OF TYPE 2 DIABETES MELLITUS (T2DM) IS ESCALATING GLOBALLY. PATIENTS SUFFER FROM MULTIPLE COMPLICATIONS INCLUDING THE DEVELOPMENT OF CHRONIC WOUNDS THAT CAN LEAD TO AMPUTATION. THESE WOUNDS ARE CHARACTERISED BY AN INFLAMMATORY ENVIRONMENT INCLUDING ELEVATED TUMOUR NECROSIS FACTOR ALPHA (TNF-ALPHA). DERMAL FIBROBLASTS (DF) ARE CRITICAL FOR EFFECTIVE WOUND HEALING, SO WE SOUGHT TO ESTABLISH WHETHER THERE WERE ANY DIFFERENCES IN DF CULTURED FROM T2DM DONORS OR THOSE WITHOUT DIABETES (ND-DF). ND- AND T2DM-DF WHEN CULTURED SIMILARLY IN VITRO SECRETED COMPARABLE CONCENTRATIONS OF TNF-ALPHA. FUNCTIONALLY, PRE-TREATMENT WITH TNF-ALPHA REDUCED THE PROLIFERATION OF ND-DF AND TRANSIENTLY ALTERED ND-DF MORPHOLOGY; HOWEVER, T2DM-DF WERE RESISTANT TO THESE TNF-ALPHA INDUCED CHANGES. IN CONTRAST, TNF-ALPHA INHIBITED ND- AND T2DM-DF MIGRATION AND MATRIX METALLOPROTEASE EXPRESSION TO THE SAME DEGREE, ALTHOUGH T2DM-DF EXPRESSED SIGNIFICANTLY HIGHER LEVELS OF TISSUE INHIBITOR OF METALLOPROTEASES (TIMP)-2. FINALLY, TNF-ALPHA SIGNIFICANTLY INCREASED THE SECRETION OF PRO-INFLAMMATORY CYTOKINES (INCLUDING CCL2, CXCL1 AND SERPINE1) IN ND-DF, WHILST THIS EFFECT IN T2DM-DF WAS BLUNTED, PRESUMABLY DUE TO THE TENDENCY TO HIGHER BASELINE PRO-INFLAMMATORY CYTOKINE EXPRESSION OBSERVED IN THIS CELL TYPE. COLLECTIVELY, THESE DATA DEMONSTRATE THAT T2DM-DF EXHIBIT A SELECTIVE LOSS OF RESPONSIVENESS TO TNF-ALPHA, PARTICULARLY REGARDING PROLIFERATIVE AND SECRETORY FUNCTIONS. THIS HIGHLIGHTS IMPORTANT PHENOTYPIC CHANGES IN T2DM-DF THAT MAY EXPLAIN THE SUSCEPTIBILITY TO CHRONIC WOUNDS IN THESE PATIENTS. 2021 7 5636 38 SERELAXIN ALLEVIATES CARDIAC FIBROSIS THROUGH INHIBITING ENDOTHELIAL-TO-MESENCHYMAL TRANSITION VIA RXFP1. RATIONALE: CARDIAC FIBROSIS IS AN INTEGRAL CONSTITUENT OF EVERY FORM OF CHRONIC HEART DISEASE, AND PERSISTENCE OF FIBROSIS REDUCES TISSUE COMPLIANCE AND ACCELERATES THE PROGRESSION TO HEART FAILURE. RELAXIN-2 IS A HUMAN HORMONE, WHICH HAS VARIOUS PHYSIOLOGICAL FUNCTIONS SUCH AS MEDIATING RENAL VASODILATION IN PREGNANCY. ITS RECOMBINANT FORM SERELAXIN HAS RECENTLY BEEN TESTED IN CLINICAL TRIALS AS A THERAPY FOR ACUTE HEART FAILURE BUT DID NOT MEET ITS PRIMARY ENDPOINTS. THE AIM OF THIS STUDY IS TO EXAMINE WHETHER SERELAXIN HAS AN ANTI-FIBROTIC EFFECT IN THE HEART AND THEREFORE COULD BE BENEFICIAL IN CHRONIC HEART FAILURE. METHODS: WE UTILIZED TWO DIFFERENT CARDIAC FIBROSIS MOUSE MODELS (ASCENDING AORTIC CONSTRICTION (AAC) AND ANGIOTENSIN II (ATII) ADMINISTRATION VIA OSMOTIC MINIPUMPS) TO ASSESS THE ANTI-FIBROTIC POTENTIAL OF SERELAXIN. HISTOLOGICAL ANALYSIS, IMMUNOFLUORESCENCE STAINING AND MOLECULAR ANALYSIS WERE PERFORMED TO ASSESS THE FIBROSIS LEVEL AND INDICATE ENDOTHELIAL CELLS WHICH ARE UNDERGOING ENDMT. IN VITRO TGFBETA1-INDUCED ENDOTHELIAL-TO-MESENCHYMAL TRANSITION (ENDMT) ASSAYS WERE PERFORMED IN HUMAN CORONARY ARTERY ENDOTHELIAL CELLS AND MOUSE CARDIAC ENDOTHELIAL CELLS (MCECS) AND WERE EXAMINED USING MOLECULAR METHODS. CHROMATIN IMMUNOPRECIPITATION-QPCR ASSAY WAS UTILIZED TO IDENTIFY THE SERELAXIN EFFECT ON CHROMATIN REMODELING IN THE RXFP1 PROMOTER REGION IN MCECS. RESULTS: OUR RESULTS DEMONSTRATE A SIGNIFICANT AND DOSE-DEPENDENT ANTI-FIBROTIC EFFECT OF SERELAXIN IN THE HEART IN BOTH MODELS. WE FURTHER SHOW THAT SERELAXIN MEDIATES THIS EFFECT, AT LEAST IN PART, THROUGH INHIBITION OF ENDMT THROUGH THE ENDOTHELIAL RELAXIN FAMILY PEPTIDE RECEPTOR 1 (RXFP1). WE FURTHER DEMONSTRATE THAT SERELAXIN ADMINISTRATION IS ABLE TO INCREASE ITS OWN RECEPTOR EXPRESSION (RXFP1) THROUGH EPIGENETIC REGULATION IN FORM OF HISTONE MODIFICATIONS BY ATTENUATING TGFBETA-PSMAD2/3 SIGNALING IN ENDOTHELIAL CELLS. CONCLUSIONS: THIS STUDY IS THE FIRST TO IDENTIFY THAT SERELAXIN INCREASES THE EXPRESSION OF ITS OWN RECEPTOR RXFP1 AND THAT THIS MEDIATES THE INHIBITION OF ENDMT AND CARDIAC FIBROSIS, SUGGESTING THAT SERELAXIN MAY HAVE A BENEFICIAL EFFECT AS ANTI-FIBROTIC THERAPY IN CHRONIC HEART FAILURE. 2020 8 1966 38 EPIGENETIC ALTERATION OF PRKCDBP IN COLORECTAL CANCERS AND ITS IMPLICATION IN TUMOR CELL RESISTANCE TO TNFALPHA-INDUCED APOPTOSIS. PURPOSE: PRKCDBP IS A PUTATIVE TUMOR SUPPRESSOR IN WHICH ALTERATION HAS BEEN OBSERVED IN SEVERAL HUMAN CANCERS. WE INVESTIGATED EXPRESSION AND FUNCTION OF PRKCDBP IN COLORECTAL CELLS AND TISSUES TO EXPLORE ITS CANDIDACY AS A SUPPRESSOR IN COLORECTAL TUMORIGENESIS. EXPERIMENTAL DESIGN: EXPRESSION AND METHYLATION STATUS OF PRKCDBP AND ITS EFFECT ON TUMOR GROWTH WERE EVALUATED. TRANSCRIPTIONAL REGULATION BY NF-KAPPAB SIGNALING WAS DEFINED BY LUCIFERASE REPORTER AND CHROMATIN IMMUNOPRECIPITATION ASSAYS. RESULTS: PRKCDBP EXPRESSION WAS HARDLY DETECTABLE IN 29 OF 80 (36%) PRIMARY TUMORS AND 11 OF 19 (58%) CELL LINES, AND ITS ALTERATION CORRELATED WITH TUMOR STAGE AND GRADE. PROMOTER HYPERMETHYLATION WAS COMMONLY FOUND IN CANCERS. PRKCDBP EXPRESSION INDUCED THE G(1) CELL-CYCLE ARREST AND INCREASED CELLULAR SENSITIVITY TO VARIOUS APOPTOTIC STRESSES. PRKCDBP WAS INDUCED BY TNFALPHA, AND ITS LEVEL CORRELATED WITH TUMOR CELL SENSITIVITY TO TNFALPHA-INDUCED APOPTOSIS. PRKCDBP INDUCTION BY TNFALPHA WAS DISRUPTED BY BLOCKING NF-KAPPAB SIGNALING WHILE IT WAS ENHANCED BY RELA TRANSFECTION. THE PRKCDBP PROMOTER ACTIVITY WAS INCREASED IN RESPONSE TO TNFALPHA, AND THIS RESPONSE WAS ABOLISHED BY DISRUPTION OF A KAPPAB SITE IN THE PROMOTER. PRKCDBP DELAYED THE FORMATION AND GROWTH OF XENOGRAFT TUMORS AND IMPROVED TUMOR RESPONSE TO TNFALPHA-INDUCED APOPTOSIS. CONCLUSIONS: PRKCDBP IS A PROAPOPTOTIC TUMOR SUPPRESSOR WHICH IS COMMONLY ALTERED IN COLORECTAL CANCER BY PROMOTER HYPERMETHYLATION, AND ITS GENE TRANSCRIPTION IS DIRECTLY ACTIVATED BY NF-KAPPAB IN RESPONSE TO TNFALPHA. THIS SUGGESTS THAT PRKCDBP INACTIVATION MAY CONTRIBUTE TO TUMOR PROGRESSION BY REDUCING CELLULAR SENSITIVITY TO TNFALPHA AND OTHER STRESSES, PARTICULARLY UNDER CHRONIC INFLAMMATORY MICROENVIRONMENT. 2011 9 984 33 CHRONIC PSYCHOLOGICAL STRESS ALTERS GENE EXPRESSION IN RAT COLON EPITHELIAL CELLS PROMOTING CHROMATIN REMODELING, BARRIER DYSFUNCTION AND INFLAMMATION. CHRONIC STRESS IS COMMONLY ASSOCIATED WITH ENHANCED ABDOMINAL PAIN (VISCERAL HYPERSENSITIVITY), BUT THE CELLULAR MECHANISMS UNDERLYING HOW CHRONIC STRESS INDUCES VISCERAL HYPERSENSITIVITY ARE POORLY UNDERSTOOD. IN THIS STUDY, WE EXAMINED CHANGES IN GENE EXPRESSION IN COLON EPITHELIAL CELLS FROM A RAT MODEL USING RNA-SEQUENCING TO EXAMINE STRESS-INDUCED CHANGES TO THE TRANSCRIPTOME. FOLLOWING CHRONIC STRESS, THE MOST SIGNIFICANTLY UP-REGULATED GENES INCLUDED ATG16L1, COQ10B, DCAF13, NAT2, PTBP2, RRAS2, SPINK4 AND DOWN-REGULATED GENES INCLUDING ABAT, CITED2, CNNM2, DAB2IP, PLEKHM1, SCD2, AND TAB2. THE PRIMARY ALTERED BIOLOGICAL PROCESSES REVEALED BY NETWORK ENRICHMENT ANALYSIS WERE INFLAMMATION/IMMUNE RESPONSE, TISSUE MORPHOGENESIS AND DEVELOPMENT, AND NUCLEOSOME/CHROMATIN ASSEMBLY. THE MOST SIGNIFICANTLY DOWN-REGULATED PROCESS WAS THE DIGESTIVE SYSTEM DEVELOPMENT/FUNCTION, WHEREAS THE MOST SIGNIFICANTLY UP-REGULATED PROCESSES WERE INFLAMMATORY RESPONSE, ORGANISMAL INJURY, AND CHROMATIN REMODELING MEDIATED BY H3K9 METHYLATION. FURTHERMORE, A SUBPOPULATION OF STRESSED RATS DEMONSTRATED VERY SIGNIFICANTLY ALTERED GENE EXPRESSION AND TRANSCRIPT ISOFORMS, ENRICHED FOR THE DIFFERENTIAL EXPRESSION OF GENES INVOLVED IN THE INFLAMMATORY RESPONSE, INCLUDING UPREGULATION OF CYTOKINE AND CHEMOKINE RECEPTOR GENE EXPRESSION COUPLED WITH DOWNREGULATION OF EPITHELIAL ADHERENS AND TIGHT JUNCTION MRNAS. IN SUMMARY, THESE FINDINGS SUPPORT THAT CHRONIC STRESS IS ASSOCIATED WITH INCREASED LEVELS OF CYTOKINES AND CHEMOKINES, THEIR DOWNSTREAM SIGNALING PATHWAYS COUPLED TO DYSREGULATION OF INTESTINAL CELL DEVELOPMENT AND FUNCTION. EPIGENETIC REGULATION OF CHROMATIN REMODELING LIKELY PLAYS A PROMINENT ROLE IN THIS PROCESS. RESULTS ALSO SUGGEST THAT SUPER ENHANCERS PLAY A PRIMARY ROLE IN CHRONIC STRESS-ASSOCIATED INTESTINAL BARRIER DYSFUNCTION. 2022 10 5788 23 SREBP1 DRIVES KERATIN-80-DEPENDENT CYTOSKELETAL CHANGES AND INVASIVE BEHAVIOR IN ENDOCRINE-RESISTANT ERALPHA BREAST CANCER. APPROXIMATELY 30% OF ERALPHA BREAST CANCER PATIENTS RELAPSE WITH METASTATIC DISEASE FOLLOWING ADJUVANT ENDOCRINE THERAPIES. THE CONNECTION BETWEEN ACQUISITION OF DRUG RESISTANCE AND INVASIVE POTENTIAL IS POORLY UNDERSTOOD. IN THIS STUDY, WE DEMONSTRATE THAT THE TYPE II KERATIN TOPOLOGICAL ASSOCIATING DOMAIN UNDERGOES EPIGENETIC REPROGRAMMING IN AROMATASE INHIBITORS (AI)-RESISTANT CELLS, LEADING TO KERATIN-80 (KRT80) UPREGULATION. KRT80 EXPRESSION IS DRIVEN BY DE NOVO ENHANCER ACTIVATION BY STEROL REGULATORY ELEMENT-BINDING PROTEIN 1 (SREBP1). KRT80 UPREGULATION DIRECTLY PROMOTES CYTOSKELETAL REARRANGEMENTS AT THE LEADING EDGE, INCREASED FOCAL ADHESION AND CELLULAR STIFFENING, COLLECTIVELY PROMOTING CANCER CELL INVASION. SHEARWAVE ELASTICITY IMAGING PERFORMED ON PROSPECTIVELY RECRUITED PATIENTS CONFIRMS KRT80 LEVELS CORRELATE WITH STIFFER TUMORS. IMMUNOHISTOCHEMISTRY SHOWED INCREASED KRT80-POSITIVE CELLS AT RELAPSE AND, USING SEVERAL CLINICAL ENDPOINTS, KRT80 EXPRESSION ASSOCIATES WITH POOR SURVIVAL. COLLECTIVELY, OUR DATA UNCOVER AN UNPREDICTED AND POTENTIALLY TARGETABLE DIRECT LINK BETWEEN EPIGENETIC AND CYTOSKELETAL REPROGRAMMING PROMOTING CELL INVASION IN RESPONSE TO CHRONIC AI TREATMENT. 2019 11 1806 33 EFFECT OF TRANSCRIPTION INHIBITION AND GENERATION OF SUPPRESSIVE VIRAL NON-CODING RNAS. BACKGROUND: HIV-1 PATIENTS RECEIVING COMBINATION ANTIRETROVIRAL THERAPY (CART) SURVIVE INFECTION BUT REQUIRE LIFE-LONG ADHERENCE AT HIGH EXPENSE. IN CHRONIC CART-TREATED PATIENTS WITH UNDETECTABLE VIRAL TITERS, CELL-ASSOCIATED VIRAL RNA IS STILL DETECTABLE, POINTING TO LOW-LEVEL VIRAL TRANSCRIPTIONAL LEAKINESS. TO DATE, THERE ARE NO FDA-APPROVED DRUGS AGAINST HIV-1 TRANSCRIPTION. WE HAVE PREVIOUSLY SHOWN THAT F07#13, A THIRD GENERATION TAT PEPTIDE MIMETIC WITH COMPETITIVE ACTIVITY AGAINST CDK9/T1-TAT BINDING SITES, INHIBITS HIV-1 TRANSCRIPTION IN VITRO AND IN VIVO. RESULTS: HERE, WE DEMONSTRATE THAT INCREASING CONCENTRATIONS OF F07#13 (0.01, 0.1, 1 MICROM) CAUSE A DECREASE IN TAT LEVELS IN A DOSE-DEPENDENT MANNER BY INHIBITING THE CDK9/T1-TAT COMPLEX FORMATION AND SUBSEQUENT UBIQUITIN-MEDIATED TAT SEQUESTRATION AND DEGRADATION. OUR DATA INDICATE THAT COMPLEXES I AND IV CONTAIN DISTINCT PATTERNS OF UBIQUITINATED TAT AND THAT TRANSCRIPTIONAL INHIBITION INDUCED BY F07#13 CAUSES AN OVERALL REDUCTION IN TAT LEVELS. THIS REDUCTION MAY BE TRIGGERED BY F07#13 BUT ULTIMATELY IS MEDIATED BY TAR-GAG VIRAL RNAS THAT BIND SUPPRESSIVE TRANSCRIPTION FACTORS (SIMILAR TO 7SK, NRON, HOTAIR, AND XIST LNCRNAS) TO ENHANCE TRANSCRIPTIONAL GENE SILENCING AND LATENCY. THESE RNAS COMPLEX WITH PRC2, SIN3A, AND CUL4B, RESULTING IN EPIGENETIC MODIFICATIONS. FINALLY, WE OBSERVED AN F07#13-MEDIATED DECREASE OF VIRAL BURDEN BY TARGETING THE R REGION OF THE LONG TERMINAL REPEAT (HIV-1 PROMOTER REGION, LTR), PROMOTING BOTH PAUSED POLYMERASES AND INCREASED EFFICIENCY OF CRISPR/CAS9 EDITING IN INFECTED CELLS. THIS IMPLIES THAT GENE EDITING MAY BE BEST PERFORMED UNDER A REPRESSED TRANSCRIPTIONAL STATE. CONCLUSIONS: COLLECTIVELY, OUR RESULTS INDICATE THAT F07#13, WHICH CAN TERMINATE RNA POLYMERASE II AT DISTINCT SITES, CAN GENERATE SCAFFOLD RNAS, WHICH MAY ASSEMBLE INTO SPECIFIC SETS OF "RNA MACHINES" THAT CONTRIBUTE TO GENE REGULATION. IT REMAINS TO BE SEEN WHETHER THESE EFFECTS CAN ALSO BE SEEN IN VARIOUS CLADES THAT HAVE VARYING PROMOTER STRENGTH, MUTANT LTRS, AND IN PATIENT SAMPLES. 2019 12 3390 30 HOPX PLAYS A CRITICAL ROLE IN ANTIRETROVIRAL DRUGS INDUCED EPIGENETIC MODIFICATION AND CARDIAC HYPERTROPHY. PEOPLE LIVING WITH HIV (PLWH) HAVE TO TAKE AN ANTIRETROVIRAL THERAPY (ART) FOR LIFE AND SHOW NONCOMMUNICABLE ILLNESSES SUCH AS CHRONIC INFLAMMATION, IMMUNE ACTIVATION, AND MULTIORGAN DYSREGULATION. RECENT STUDIES SUGGEST THAT LONG-TERM USE OF ART INDUCES COMORBID CONDITIONS AND IS ONE OF THE LEADING CAUSES OF HEART FAILURE IN PLWH. HOWEVER, THE MOLECULAR MECHANISM OF ANTIRETROVIRAL DRUGS (ARVS) INDUCED HEART FAILURE IS UNCLEAR. TO DETERMINE THE MECHANISM OF ARVS INDUCED CARDIAC DYSFUNCTION, WE PERFORMED GLOBAL TRANSCRIPTOMIC PROFILING OF ARVS TREATED NEONATAL RAT VENTRICULAR CARDIOMYOCYTES IN CULTURE. DIFFERENTIALLY EXPRESSED GENES WERE IDENTIFIED BY RNA-SEQUENCING. OUR DATA SHOW THAT ARVS TREATMENT CAUSES UPREGULATION OF SEVERAL BIOLOGICAL FUNCTIONS ASSOCIATED WITH CARDIOTOXICITY, HYPERTROPHY, AND HEART FAILURE. GLOBAL GENE EXPRESSION DATA WERE VALIDATED IN CARDIAC TISSUE ISOLATED FROM HIV PATIENTS HAVING A HISTORY OF ART. INTERESTINGLY, WE FOUND THAT HOMEODOMAIN-ONLY PROTEIN HOMEOBOX (HOPX) EXPRESSION WAS SIGNIFICANTLY INCREASED IN CARDIOMYOCYTES TREATED WITH ARVS AND IN THE HEART TISSUE OF HIV PATIENTS. FURTHERMORE, WE FOUND THAT HOPX PLAYS A CRUCIAL ROLE IN ARVS MEDIATED CELLULAR HYPERTROPHY. MECHANISTICALLY, WE FOUND THAT HOPX PLAYS A CRITICAL ROLE IN EPIGENETIC REGULATION, THROUGH DEACETYLATION OF HISTONE, WHILE THE HDAC INHIBITOR, TRICHOSTATIN A, CAN RESTORE THE ACETYLATION LEVEL OF HISTONE 3 IN THE PRESENCE OF ARVS. 2021 13 3327 30 HISTONE DEACETYLASE 4 PROMOTES CHOLESTATIC LIVER INJURY IN THE ABSENCE OF PROHIBITIN-1. PROHIBITIN-1 (PHB1) IS AN EVOLUTIONARILY CONSERVED PLEIOTROPIC PROTEIN THAT PARTICIPATES IN DIVERSE PROCESSES DEPENDING ON ITS SUBCELLULAR LOCALIZATION AND INTERACTOME. RECENT DATA HAVE INDICATED A DIVERSE ROLE FOR PHB1 IN THE PATHOGENESIS OF OBESITY, CANCER, AND INFLAMMATORY BOWEL DISEASE, AMONG OTHERS. DATA PRESENTED HERE SUGGEST THAT PHB1 IS ALSO LINKED TO CHOLESTATIC LIVER DISEASE. EXPRESSION OF PHB1 IS MARKEDLY REDUCED IN PATIENTS WITH PRIMARY BILIARY CIRRHOSIS AND BILIARY ATRESIA OR WITH ALAGILLE SYNDROME, TWO MAJOR PEDIATRIC CHOLESTATIC CONDITIONS. IN THE EXPERIMENTAL MODEL OF BILE DUCT LIGATION, SILENCING OF PHB1 INDUCED LIVER FIBROSIS, REDUCED ANIMAL SURVIVAL, AND INDUCED BILE DUCT PROLIFERATION. IMPORTANTLY, THE MODULATORY EFFECT OF PHB1 IS NOT DEPENDENT ON ITS KNOWN MITOCHONDRIAL FUNCTION. ALSO, PHB1 INTERACTS WITH HISTONE DEACETYLASE 4 (HDAC4) IN THE PRESENCE OF BILE ACIDS. HENCE, PHB1 DEPLETION LEADS TO INCREASED NUCLEAR HDAC4 CONTENT AND ITS ASSOCIATED EPIGENETIC CHANGES. REMARKABLY, HDAC4 SILENCING AND THE ADMINISTRATION OF THE HDAC INHIBITOR PARTHENOLIDE DURING OBSTRUCTIVE CHOLESTASIS IN VIVO PROMOTE GENOMIC REPROGRAMMING, LEADING TO REGRESSION OF THE FIBROTIC PHENOTYPE IN LIVER-SPECIFIC PHB1 KNOCKOUT MICE. CONCLUSION: PHB1 IS AN IMPORTANT MEDIATOR OF CHOLESTATIC LIVER INJURY THAT REGULATES THE ACTIVITY OF HDAC4, WHICH CONTROLS SPECIFIC EPIGENETIC MARKERS; THESE RESULTS IDENTIFY POTENTIAL NOVEL STRATEGIES TO TREAT LIVER INJURY AND FIBROSIS, PARTICULARLY AS A CONSEQUENCE OF CHRONIC CHOLESTASIS. 2015 14 5153 25 PPP2R2B HYPERMETHYLATION CAUSES ACQUIRED APOPTOSIS DEFICIENCY IN SYSTEMIC AUTOIMMUNE DISEASES. CHRONIC INFLAMMATION CAUSES TARGET ORGAN DAMAGE IN PATIENTS WITH SYSTEMIC AUTOIMMUNE DISEASES. THE FACTORS THAT ALLOW THIS PROTRACTED RESPONSE ARE POORLY UNDERSTOOD. WE ANALYZED THE TRANSCRIPTIONAL REGULATION OF PPP2R2B (B55SS), A MOLECULE NECESSARY FOR THE TERMINATION OF THE IMMUNE RESPONSE, IN PATIENTS WITH AUTOIMMUNE DISEASES. ALTERED EXPRESSION OF B55SS CONDITIONED RESISTANCE TO CYTOKINE WITHDRAWAL-INDUCED DEATH (CWID) IN PATIENTS WITH AUTOIMMUNE DISEASES. THE IMPAIRED UPREGULATION OF B55SS WAS CAUSED BY INFLAMMATION-DRIVEN HYPERMETHYLATION OF SPECIFIC CYTOSINES LOCATED WITHIN A REGULATORY ELEMENT OF PPP2R2B PREVENTING CTCF BINDING. THIS PHENOTYPE COULD BE INDUCED IN HEALTHY T CELLS BY EXPOSURE TO TNF-ALPHA. OUR RESULTS REVEAL A GENE WHOSE EXPRESSION IS AFFECTED BY AN ACQUIRED DEFECT, THROUGH AN EPIGENETIC MECHANISM, IN THE SETTING OF SYSTEMIC AUTOIMMUNITY. BECAUSE FAILURE TO REMOVE ACTIVATED T CELLS THROUGH CWID COULD CONTRIBUTE TO AUTOIMMUNE PATHOLOGY, THIS MECHANISM ILLUSTRATES A VICIOUS CYCLE THROUGH WHICH AUTOIMMUNE INFLAMMATION CONTRIBUTES TO ITS OWN PERPETUATION. 2019 15 1008 27 CHRONIC VOLUNTARY ALCOHOL CONSUMPTION ALTERS PROMOTER METHYLATION AND EXPRESSION OF FGF-2 AND FGFR1. ALCOHOL ABUSE ACCOUNTS FOR 3.3 MILLION DEATHS ANNUALLY, RENDERING IT A GLOBAL HEALTH ISSUE. RECENTLY, FIBROBLAST GROWTH FACTOR 2 (FGF-2) AND ITS TARGET, FIBROBLAST GROWTH FACTOR RECEPTOR 1 (FGFR1), WERE DISCOVERED TO POSITIVELY REGULATE ALCOHOL-DRINKING BEHAVIORS IN MICE. WE TESTED WHETHER ALCOHOL INTAKE AND WITHDRAWAL ALTER DNA METHYLATION OF FGF-2 AND FGFR1 AND IF THERE IS A CORRELATION REGARDING MRNA EXPRESSION OF THESE GENES. BLOOD AND BRAIN TISSUES OF MICE RECEIVING ALCOHOL INTERMITTENTLY OVER A SIX-WEEK PERIOD WERE ANALYZED USING DIRECT BISULFITE SEQUENCING AND QRT-PCR ANALYSIS. ASSESSMENT OF FGF-2 AND FGFR1 PROMOTER METHYLATION REVEALED CHANGES IN THE METHYLATION OF CYTOSINES IN THE ALCOHOL GROUP COMPARED WITH THE CONTROL GROUP. MOREOVER, WE SHOWED THAT THE ALTERED CYTOSINES COINCIDED WITH BINDING MOTIVES OF SEVERAL TRANSCRIPTION FACTORS. WE ALSO FOUND THAT FGF-2 AND FGFR1 GENE EXPRESSION WAS SIGNIFICANTLY DECREASED IN ALCOHOL-RECEIVING MICE COMPARED WITH CONTROL LITTERMATES, AND THAT THIS EFFECT WAS SPECIFICALLY DETECTED IN THE DORSOMEDIAL STRIATUM, A BRAIN REGION INVOLVED IN THE CIRCUITRY OF THE REWARD SYSTEM. OVERALL, OUR DATA SHOWED ALCOHOL-INDUCED ALTERATIONS IN BOTH MRNA EXPRESSION AND METHYLATION PATTERN OF FGF-2 AND FGFR1. FURTHERMORE, THESE ALTERATIONS SHOWED A REWARD SYSTEM REGIONAL SPECIFICITY, THEREFORE, RESEMBLING POTENTIAL TARGETS FOR FUTURE PHARMACOLOGICAL INTERVENTIONS. 2023 16 2758 29 EXPRESSION OF HORMONAL CARCINOGENESIS GENES AND RELATED REGULATORY MICRORNAS IN UTERUS AND OVARIES OF DDT-TREATED FEMALE RATS. THE INSECTICIDE DICHLORODIPHENYLTRICHLOROETHANE (DDT) IS A NONMUTAGENIC XENOBIOTIC COMPOUND ABLE TO EXERT ESTROGEN-LIKE EFFECTS RESULTING IN ACTIVATION OF ESTROGEN RECEPTOR-ALPHA (ERALPHA) FOLLOWED BY CHANGED EXPRESSION OF ITS DOWNSTREAM TARGET GENES. IN ADDITION, STUDIES PERFORMED OVER RECENT YEARS SUGGEST THAT DDT MAY ALSO INFLUENCE EXPRESSION OF MICRORNAS. HOWEVER, AN IMPACT OF DDT ON EXPRESSION OF ER, MICRORNAS, AND RELATED TARGET GENES HAS NOT BEEN FULLY ELUCIDATED. HERE, USING REAL-TIME PCR, WE ASSESSED CHANGES IN EXPRESSION OF KEY GENES INVOLVED IN HORMONAL CARCINOGENESIS AS WELL AS POTENTIALLY RELATED REGULATORY ONCOGENIC/TUMOR SUPPRESSOR MICRORNAS AND THEIR TARGET GENES IN THE UTERUS AND OVARIES OF FEMALE WISTAR RATS DURING SINGLE AND CHRONIC MULTIPLE-DOSE DDT EXPOSURE. WE FOUND THAT APPLYING DDT RESULTS IN ALTERED EXPRESSION OF MICRORNAS-221, -222, -205, -126A, AND -429, THEIR TARGET GENES (PTEN, DICER1), AS WELL AS GENES INVOLVED IN HORMONAL CARCINOGENESIS (ESR1, PGR, CCND1, CYP19A1). NOTABLY, CYP19A1 EXPRESSION SEEMS TO BE ALSO REGULATED BY MICRORNAS-221, -222, AND -205. THE DATA SUGGEST THAT EPIGENETIC EFFECTS INDUCED BY DDT AS A POTENTIAL CARCINOGEN MAY BE BASED ON AT LEAST TWO MECHANISMS: (I) ACTIVATION OF ERALPHA FOLLOWED BY ALTERED EXPRESSION OF THE TARGET GENES ENCODING RECEPTOR PGR AND CCND1 AS WELL AS IMPAIRED EXPRESSION OF CYP19A1, AFFECTING, THEREBY, CELL HORMONE BALANCE; AND (II) CHANGED EXPRESSION OF MICRORNAS RESULTING IN IMPAIRED EXPRESSION OF RELATED TARGET GENES INCLUDING REDUCED LEVEL OF CYP19A1 MRNA. 2017 17 1334 30 DEREGULATION OF AIOLOS EXPRESSION IN CHRONIC LYMPHOCYTIC LEUKEMIA IS ASSOCIATED WITH EPIGENETIC MODIFICATIONS. CHRONIC LYMPHOCYTIC LEUKEMIA (CLL) IS CHARACTERIZED BY A CLONAL ACCUMULATION OF MATURE NEOPLASTIC B CELLS THAT ARE RESISTANT TO APOPTOSIS. AIOLOS, A MEMBER OF THE IKAROS FAMILY OF ZINC-FINGER TRANSCRIPTION FACTORS, PLAYS AN IMPORTANT ROLE IN THE CONTROL OF MATURE B LYMPHOCYTE DIFFERENTIATION AND MATURATION. IN THIS STUDY, WE SHOWED THAT AIOLOS EXPRESSION IS UP-REGULATED IN B-CLL CELLS. THIS OVEREXPRESSION DOES NOT IMPLICATE ISOFORM IMBALANCE OR DISTURB AIOLOS SUBCELLULAR LOCALIZATION. THE CHROMATIN STATUS AT THE AIOLOS PROMOTER IN CLL IS DEFINED BY THE DEMETHYLATION OF DNA AND AN ENRICHMENT OF EUCHROMATIN ASSOCIATED HISTONE MARKERS, SUCH AS THE DIMETHYLATION OF THE LYSINE 4 ON HISTONE H3. THESE EPIGENETIC MODIFICATIONS SHOULD ALLOW ITS UPSTREAM EFFECTORS, SUCH AS NUCLEAR FACTOR-KAPPAB, CONSTITUTIVELY ACTIVATED IN CLL, TO GAIN ACCESS TO PROMOTER, RESULTING UP-REGULATION OF AIOLOS. TO DETERMINE THE CONSEQUENCES OF AIOLOS DEREGULATION IN CLL, WE ANALYZED THE EFFECTS OF AIOLOS OVEREXPRESSION OR DOWN-REGULATION ON APOPTOSIS. AIOLOS IS INVOLVED IN CELL SURVIVAL BY REGULATING THE EXPRESSION OF SOME BCL-2 FAMILY MEMBERS. OUR RESULTS STRONGLY SUGGEST THAT AIOLOS DEREGULATION BY EPIGENETIC MODIFICATIONS MAY BE A HALLMARK OF CLL. 2011 18 4001 40 LOSS OF MEN1 LEADS TO RENAL FIBROSIS AND DECREASES HGF-ADAMTS5 PATHWAY ACTIVITY VIA AN EPIGENETIC MECHANISM. BACKGROUND: RENAL FIBROSIS IS A SERIOUS CONDITION THAT RESULTS IN THE DEVELOPMENT OF CHRONIC KIDNEY DISEASES. THE MEN1 GENE IS AN EPIGENETIC REGULATOR THAT ENCODES THE MENIN PROTEIN AND ITS ROLE IN KIDNEY TISSUE REMAINS UNCLEAR. METHODS: KIDNEY HISTOLOGY WAS EXAMINED ON PARAFFIN SECTIONS STAINED WITH HEMATOXYLIN-EOSIN STAINING. MASSON'S TRICHROME STAINING AND SIRIUS RED STAINING WERE USED TO ANALYZE RENAL FIBROSIS. GENE AND PROTEIN EXPRESSION WERE DETERMINED BY QUANTITATIVE REAL-TIME PCR (QPCR) AND WESTERN BLOT, RESPECTIVELY. IMMUNOHISTOCHEMISTRY STAINING IN THE KIDNEY TISSUES FROM MICE OR PATIENTS WAS USED TO EVALUATE PROTEIN LEVELS. FLOW CYTOMETRY WAS USED TO ANALYZE THE CELL CYCLE DISTRIBUTIONS AND APOPTOSIS. RNA-SEQUENCING WAS PERFORMED FOR DIFFERENTIAL EXPRESSION GENES IN THE KIDNEY TISSUES OF THE MEN1F/F AND MEN1?/? MICE. CHROMATIN IMMUNOPRECIPITATION SEQUENCING (CHIP-SEQ) WAS CARRIED OUT FOR IDENTIFICATION OF MENIN- AND H3K4ME3-ENRICHED REGIONS WITHIN THE WHOLE GENOME IN THE MOUSE KIDNEY TISSUE. CHIP-QPCR ASSAYS WERE PERFORMED FOR OCCUPANCY OF MENIN AND H3K4ME3 AT THE GENE PROMOTER REGIONS. LUCIFERASE REPORTER ASSAY WAS USED TO DETECT THE PROMOTER ACTIVITY. THE EXACERBATED UNILATERAL URETERAL OBSTRUCTION (UUO) MODELS IN THE MEN1F/F AND MEN1?/? MICE WERE USED TO ASSESS THE PHARMACOLOGICAL EFFECTS OF RH-HGF ON RENAL FIBROSIS. RESULTS: THE EXPRESSION OF MEN1 IS REDUCE IN KIDNEY TISSUES OF FIBROTIC MOUSE AND HUMAN DIABETIC PATIENTS AND TREATMENT WITH FIBROTIC FACTOR RESULTS IN THE DOWNREGULATION OF MEN1 EXPRESSION IN RENAL TUBULAR EPITHELIAL CELLS (RTECS). DISRUPTION OF MEN1 IN RTECS LEADS TO HIGH EXPRESSION OF ALPHA-SMA AND COLLAGEN 1, WHEREAS MEN1 OVEREXPRESSION RESTRAINS EPITHELIAL-TO-MESENCHYMAL TRANSITION (EMT) INDUCED BY TGF-BETA TREATMENT. CONDITIONAL KNOCKOUT OF MEN1 RESULTED IN CHRONIC RENAL FIBROSIS AND UUO-INDUCED TUBULOINTERSTITIAL FIBROSIS (TIF), WHICH IS ASSOCIATED WITH AN INCREASED INDUCTION OF EMT, G2/M ARREST AND JNK SIGNALING. MECHANISTICALLY, MENIN RECRUITS AND INCREASES H3K4ME3 AT THE PROMOTER REGIONS OF HEPATOCYTE GROWTH FACTOR (HGF) AND A DISINTEGRIN AND METALLOPROTEINASE WITH THROMBOSPONDIN MOTIFS 5 (ADAMTS5) GENES AND ENHANCES THEIR TRANSCRIPTIONAL ACTIVATION. IN THE UUO MICE MODEL, EXOGENOUS HGF RESTORED THE EXPRESSION OF ADAMTS5 AND AMELIORATED RENAL FIBROSIS INDUCED BY MEN1 DEFICIENCY. CONCLUSIONS: THESE FINDINGS DEMONSTRATE THAT MEN1 IS AN ESSENTIAL ANTIFIBROTIC FACTOR IN RENAL FIBROGENESIS AND COULD BE A POTENTIAL TARGET FOR ANTIFIBROTIC THERAPY. 2022 19 1461 36 DISRUPTION OF RCAN1.4 EXPRESSION MEDIATED BY YY1/HDAC2 MODULATES CHRONIC RENAL ALLOGRAFT INTERSTITIAL FIBROSIS. CHRONIC ALLOGRAFT DYSFUNCTION (CAD) IS A MAJOR FACTOR THAT HINDERS KIDNEY TRANSPLANT SURVIVAL IN THE LONG RUN. EPITHELIAL-MESENCHYMAL TRANSITION (EMT) HAS BEEN CONFIRMED TO SIGNIFICANTLY CONTRIBUTE TO INTERSTITIAL FIBROSIS/TUBULAR ATROPHY (IF/TA), WHICH IS THE MAIN HISTOPATHOLOGICAL FEATURE OF CAD. ABERRANT EXPRESSION OF THE REGULATOR OF CALCINEURIN 1 (RCAN1), RECOGNIZED AS AN ENDOGENOUS INHIBITOR OF THE CALCINEURIN PHOSPHATASE, HAS BEEN SHOWN TO BE EXTENSIVELY INVOLVED IN VARIOUS KIDNEY DISEASES. HOWEVER, IT REMAINS UNCLEAR HOW RCAN1.4 REGULATES IF/TA FORMATION IN CAD PATIENTS. HEREIN, AN IN VIVO MOUSE RENAL TRANSPLANTATION MODEL AND AN IN VITRO MODEL OF HUMAN RENAL TUBULAR EPITHELIAL CELLS (HK-2) TREATED WITH TUMOR NECROSIS FACTOR-ALPHA (TNF-ALPHA) WERE EMPLOYED. OUR RESULTS PROVED THAT RCAN1.4 EXPRESSION WAS DECREASED IN VIVO AND IN VITRO, IN ADDITION TO THE UP-REGULATION OF YIN YANG 1 (YY1), A TRANSCRIPTION FACTOR THAT HAS BEEN REPORTED TO CONVEY MULTIPLE FUNCTIONS IN CHRONIC KIDNEY DISEASE (CKD). KNOCKING IN OF RCAN1.4 EFFICIENTLY ATTENUATED CHRONIC RENAL ALLOGRAFT INTERSTITIAL FIBROSIS IN VIVO AND INHIBITED TNF-ALPHA-INDUCED EMT IN VITRO THROUGH REGULATING ANTI-OXIDATIVE STRESS AND THE CALCINEURIN/NUCLEAR FACTOR OF ACTIVATED T CELLS CYTOPLASMIC 1 (NFATC1) SIGNALING PATHWAY. IN ADDITION, SUPPRESSION OF YY1 MEDIATED BY SHRNA OR SIRNA ALLEVIATED TNF-ALPHA-INDUCED EMT THROUGH ABOLISHING REACTIVE SPECIES PARTLY IN AN RCAN1.4-DEPENDENT MANNER. NOTABLY, WE CONFIRMED THAT YY1 NEGATIVELY REGULATED RCAN1.4 TRANSCRIPTION BY DIRECTLY INTERACTING WITH THE RCAN1.4 PROMOTER. IN ADDITION, HISTONE DEACETYLASE 2 (HDAC2) INTERACTED WITH YY1 TO FORM A MULTI-MOLECULAR COMPLEX, WHICH WAS INVOLVED IN TNF-ALPHA-INDUCED RCAN1.4 TRANSCRIPTIONAL REPRESSION. THEREFORE, RCAN1.4 IS SUGGESTED TO BE MODULATED BY THE YY1/HDAC2 TRANSCRIPTION REPRESSOR COMPLEX IN AN EPIGENETIC MANNER, WHICH IS A MEDIATED NEPHROPROTECTIVE EFFECT PARTLY THROUGH MODULATING O2?- GENERATION AND THE CALCINEURIN/NFATC1 SIGNALING PATHWAY. THUS, THE YY1-RCAN1.4 AXIS CONSTITUTES AN INNOVATIVE TARGET FOR IF/TA TREATMENT IN CAD PATIENTS. 2023 20 272 34 AGE-DEPENDENT DECREASE IN THE INDUCTION OF REGULATORY T CELLS IS ASSOCIATED WITH DECREASED EXPRESSION OF RALDH2 IN MESENTERIC LYMPH NODE DENDRITIC CELLS. A DECLINE IN IMMUNE FUNCTION WITH AGING HAS BEEN REPORTED. REGULATORY T CELL (TREG) INDUCTION IS KNOWN TO DECREASE WITH AGE, AND ELUCIDATING THE UNDERLYING MECHANISM IS IMPORTANT FOR PREVENTING AGE-RELATED DISEASES DUE TO AGE-RELATED CHRONIC INFLAMMATION. IN THE INTESTINE, DENDRITIC CELLS (DCS) PLAY AN IMPORTANT ROLE IN INDUCING TREGS SPECIFIC TO ORAL ANTIGENS, AND THEY EFFICIENTLY INDUCE TREGS VIA PRODUCTION OF RETINOIC ACID (RA), A VITAMIN A METABOLITE, CATALYZED BY THE ENZYME RETINALDEHYDE DEHYDROGENASE 2 (RALDH2). WE HAVE PREVIOUSLY REPORTED THAT IN THE MESENTERIC LYMPH NODE (MLN), A SECONDARY LYMPHOID TISSUE IN WHICH IMMUNE RESPONSES TO ORAL ANTIGENS ARE INDUCED, FOUR DC SUBSETS EXPRESS DIFFERENT LEVELS OF CD11B, CD103, AND PD-L1, AND WE HAVE REPORTED THAT THE CD11B(-)CD103(+)PD-L1(HIGH) SUBSET EXPRESSES THE HIGHEST LEVELS OF THE RALDH2 GENE AND INDUCES TREGS IN VITRO. WE EXAMINED TREG INDUCTION IN YOUNG AND AGED MICE USING A TREG INDUCTION MODEL BY ADMINISTERING A FOOD ANTIGEN, AND WE FOUND THAT ANTIGEN-SPECIFIC TREG INDUCTION WAS DECREASED IN AGED MICE. WE FURTHER INVESTIGATED THE MLN DCS, AND A SIGNIFICANT DECREASE IN RALDH2 GENE EXPRESSION WAS OBSERVED IN MLN DCS FROM AGED MICE. AS FACTORS, WE FOUND THAT THE PROPORTION OF THE CD11B(-)CD103(+)PD-L1(HIGH) SUBSET WAS DECREASED IN AGED MICE COMPARED WITH THAT IN YOUNG MICE AND THAT RALDH ENZYME ACTIVITY WAS DECREASED IN THE CD11B(-)CD103(+)PD-L1(HIGH) AND CD11B(+)CD103(+)PD-L1(HIGH) SUBSETS. FURTHERMORE, ANALYSIS OF THE METHYLATION OF THE RALDH2 GENE PROMOTER REGION REVEALED THAT CPG MOTIFS WERE MORE METHYLATED IN THE MLN DCS OF AGED MICE, SUGGESTING THAT RALDH2 EXPRESSION WAS SUPPRESSED BY EPIGENETIC CHANGES. FINALLY, WE FOUND THAT RA TREATMENT TENDED TO INCREASE TREG INDUCTION. THESE RESULTS SUGGEST THAT THE REGULATION OF RA PRODUCTION MAY BE INVOLVED IN THE AGE-RELATED DECREASE IN ANTIGEN-SPECIFIC TREG INDUCTION. 2020