1 6297 157 THE PROTECTIVE EFFECT OF HBO1 ON CIGARETTE SMOKE EXTRACT-INDUCED APOPTOSIS IN AIRWAY EPITHELIAL CELLS. PURPOSE: EPIGENETIC MODIFICATION IS ONE OF MOST IMPORTANT MECHANISMS UNDERLYING THE PATHOGENESIS OF CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD). THE PURPOSE OF THIS STUDY WAS TO DETERMINE WHETHER HISTONE ACETYLTRANSFERASE BINDING TO ORC1 (HBO1) CAN PROTECT AGAINST CIGARETTE SMOKE (CS)-INDUCED CELL APOPTOSIS AND SUSTAIN NORMAL HISTONE ACETYLATION IN COPD. METHODS: HUMAN LUNG TISSUE SAMPLES WERE OBTAINED FROM PATIENTS WHO UNDERWENT LUNG RESECTION. THE EMPHYSEMA MOUSE MODEL AND HBO1 OVEREXPRESSING MICE WERE EACH ESTABLISHED BY INTRAPERITONEAL INJECTION WITH CIGARETTE SMOKE EXTRACT (CSE) OR INTRATRACHEAL LENTIVIRAL VECTORS INSTILLATION. TUNEL (TERMINAL DEOXYNUCLEOTIDYL TRANSFERASE DUTP NICK END LABELING) ASSAYS WERE USED TO ASSESS APOPTOTIC RATIO IN MICE. THE APOPTOSIS OF HUMAN BRONCHIAL EPITHELIAL CELLS (HBECS) WAS ASSAYED BY FLOW CYTOMETRY. HBO1, B-CELL LYMPHOMA-2 (BCL-2), AND H3K14AC PROTEIN EXPRESSION WERE DETECTED BY WESTERN BLOTTING. HBO1 MRNA EXPRESSION WAS MEASURED BY QUANTITATIVE REAL-TIME POLYMERASE CHAIN REACTION. RESULTS: PROTEIN EXPRESSION OF HBO1 WAS DECREASED SIGNIFICANTLY IN LUNG TISSUE FROM COPD PATIENTS AND CSE-TREATED EMPHYSEMA MOUSE MODELS. OVEREXPRESSION OF HBO1 ATTENUATED CSE-INDUCED EMPHYSEMATOUS CHANGES, AS WELL AS APOPTOSIS IN THE LUNGS OF COPD MICE. IN VITRO, THE HBO1 PROTEIN DEGRADED IN A TIME- AND DOSE-DEPENDENT COURSE WITH CSE TREATMENT. WITH FLOW CYTOMETRY, WE PROVED THAT HBO1 COULD REVERSE THE APOPTOSIS OF HBECS INDUCED BY CSE. FURTHERMORE, HBO1 OVEREXPRESSION PROMOTED THE EXPRESSION OF ANTI-APOPTOTIC BCL-2 PROTEIN AND ENHANCED H3K14 ACETYLATION IN AIRWAY EPITHELIAL CELLS. CONCLUSION: THESE FINDINGS DEMONSTRATE THAT THE KEY HISTONE MODULATOR HBO1 PLAYS A PROTECTIVE ROLE IN COPD PATHOGENESIS THAT MAY SHED LIGHT ON POTENTIAL THERAPEUTIC TARGETS TO INHIBIT THE PROGRESS OF COPD. 2020 2 3828 52 INVOLVEMENT OF B-CELL CLL/LYMPHOMA 2 PROMOTER METHYLATION IN CIGARETTE SMOKE EXTRACT-INDUCED EMPHYSEMA. ABNORMAL APOPTOTIC EVENTS PLAY AN IMPORTANT ROLE IN THE PATHOGENESIS OF EMPHYSEMA. THE B-CELL CLL/LYMPHOMA 2 (BCL-2) FAMILY PROTEINS ARE ESSENTIAL AND CRITICAL REGULATORS OF APOPTOSIS. WE DETERMINED WHETHER THE ANTI-APOPTOTIC BCL-2 PLAY A ROLE IN THE CIGARETTE SMOKE EXTRACT (CSE)-INDUCED EMPHYSEMA. FURTHERMORE, GIVEN THE INVOLVEMENT OF EPIGENETICS IN CHRONIC OBSTRUCTIVE PULMONARY DISEASE, WE HYPOTHESIZED THAT THE DEREGULATION OF BCL-2 MIGHT BE CAUSED BY GENE METHYLATION. THE EMPHYSEMA IN BALB/C MICE WAS ESTABLISHED BY INTRAPERITONEALLY INJECTION OF CSE. 5-AZA-2'-DEOXYCYTIDINE (AZA; A DEMETHYLATION REAGENT) AND PHOSPHATE-BUFFERED SALINE WERE ALSO ADMINISTERED INTRAPERITONEALLY AS CSE. TUNEL ASSAY WAS USED TO ASSESS APOPTOTIC INDEX OF PULMONARY CELLS. THE METHYLATION STATUS OF CPG DINUCLEOTIDES WITHIN THE BCL-2 PROMOTER WAS OBSERVED IN ALL GROUPS BY BISULFITE SEQUENCING PCR. PULMONARY EXPRESSION OF BCL-2, BAX, AND CYTOCHROME C WERE MEASURED AFTER FOUR WEEKS OF TREATMENT. THE APOPTOTIC INDEX OF PULMONARY CELLS IN CSE INJECTION GROUP WAS MUCH HIGHER THAN CONTROL ((25.88 +/- 7.55)% VS (6.28 +/- 2.96)%). COMPARED TO CONTROL MICE, DECREASED EXPRESSION OF BCL-2 AND HIGH METHYLATION OF BCL-2 PROMOTER WAS OBSERVED IN CSE INJECTED MICE (0.88 +/- 0.08 VS 0.49 +/- 0.11, (3.82 +/- 1.34)% VS (35.68 +/- 5.99)%, P < 0.01).CSE TREATMENT INDUCED LUNG CELL APOPTOSIS AND DECREASED LUNG FUNCTION. AZA TREATMENT INCREASED BCL-2 EXPRESSION WITH BCL-2 PROMOTER DEMETHYLATION. AZA ALSO ALLEVIATED THE LUNG CELL APOPTOSIS AND FUNCTION FAILURE CAUSED BY CSE TREATMENT. THE DECREASED EXPRESSION OF ANTI-APOPTOTIC BCL-2 MIGHT ACCOUNT FOR THE INCREASED APOPTOSIS IN CSE INDUCED-EMPHYSEMA. APPARENTLY, EPIGENETIC ALTERNATION PLAYED A ROLE IN THIS DEREGULATION OF BCL-2 EXPRESSION, AND IT MIGHT SUPPORT THE INVOLVEMENT OF EPIGENETIC EVENTS IN THE PATHOGENESIS OF EMPHYSEMA. 2016 3 4001 57 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 4 3128 48 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 5 1966 35 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 6 3468 52 HYPOXIA-INDUCED DNA HYPERMETHYLATION IN HUMAN PULMONARY FIBROBLASTS IS ASSOCIATED WITH THY-1 PROMOTER METHYLATION AND THE DEVELOPMENT OF A PRO-FIBROTIC PHENOTYPE. BACKGROUND: PULMONARY FIBROSIS IS A DEBILITATING AND LETHAL DISEASE WITH NO EFFECTIVE TREATMENT OPTIONS. UNDERSTANDING THE PATHOLOGICAL PROCESSES AT PLAY WILL DIRECT THE APPLICATION OF NOVEL THERAPEUTIC AVENUES. HYPOXIA HAS BEEN IMPLICATED IN THE PATHOGENESIS OF PULMONARY FIBROSIS YET THE PRECISE MECHANISM BY WHICH IT CONTRIBUTES TO DISEASE PROGRESSION REMAINS TO BE FULLY ELUCIDATED. IT HAS BEEN SHOWN THAT CHRONIC HYPOXIA CAN ALTER DNA METHYLATION PATTERNS IN TUMOUR-DERIVED CELL LINES. THIS EPIGENETIC ALTERATION CAN INDUCE CHANGES IN CELLULAR PHENOTYPE WITH PROMOTER METHYLATION BEING ASSOCIATED WITH GENE SILENCING. OF PARTICULAR RELEVANCE TO IDIOPATHIC PULMONARY FIBROSIS (IPF) IS THE OBSERVATION THAT THY-1 PROMOTER METHYLATION IS ASSOCIATED WITH A MYOFIBROBLAST PHENOTYPE WHERE LOSS OF THY-1 OCCURS ALONGSIDE INCREASED ALPHA SMOOTH MUSCLE ACTIN (ALPHA-SMA) EXPRESSION. THE INITIAL AIM OF THIS STUDY WAS TO DETERMINE WHETHER HYPOXIA REGULATES DNA METHYLATION IN NORMAL HUMAN LUNG FIBROBLASTS (CCD19LU). AS IT HAS BEEN REPORTED THAT HYPOXIA SUPPRESSES THY-1 EXPRESSION DURING LUNG DEVELOPMENT WE ALSO STUDIED THE EFFECT OF HYPOXIA ON THY-1 PROMOTER METHYLATION AND GENE EXPRESSION. METHODS: CCD19LU WERE GROWN FOR UP TO 8 DAYS IN HYPOXIA AND ASSESSED FOR GLOBAL CHANGES IN DNA METHYLATION USING FLOW CYTOMETRY. REAL-TIME PCR WAS USED TO QUANTIFY EXPRESSION OF THY-1, ALPHA-SMA, COLLAGEN I AND III. GENOMIC DNA WAS BISULPHITE TREATED AND METHYLATION SPECIFIC PCR (MSPCR) WAS USED TO EXAMINE THE METHYLATION STATUS OF THE THY-1 PROMOTER. RESULTS: SIGNIFICANT GLOBAL HYPERMETHYLATION WAS DETECTED IN HYPOXIC FIBROBLASTS RELATIVE TO NORMOXIC CONTROLS AND WAS ACCOMPANIED BY INCREASED EXPRESSION OF MYOFIBROBLAST MARKERS. THY-1 MRNA EXPRESSION WAS SUPPRESSED IN HYPOXIC CELLS, WHICH WAS RESTORED WITH THE DEMETHYLATING AGENT 5-AZA-2'-DEOXYCYTIDINE. MSPCR REVEALED THAT THY-1 BECAME METHYLATED FOLLOWING FIBROBLAST EXPOSURE TO 1% O2. CONCLUSION: THESE DATA SUGGEST THAT GLOBAL AND GENE-SPECIFIC CHANGES IN DNA METHYLATION MAY PLAY AN IMPORTANT ROLE IN FIBROBLAST FUNCTION IN HYPOXIA. 2012 7 3638 47 INCREASED EXPRESSION OF BETA-DEFENSIN 1 (DEFB1) IN CHRONIC OBSTRUCTIVE PULMONARY DISEASE. ON-GOING AIRWAY INFLAMMATION IS CHARACTERISTIC FOR THE PATHOPHYSIOLOGY OF CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD). HOWEVER, THE KEY FACTORS DETERMINING THE DECREASE IN LUNG FUNCTION, AN IMPORTANT CLINICAL PARAMETER OF COPD, ARE NOT CLEAR. GENOME-WIDE LINKAGE ANALYSES PROVIDE EVIDENCE FOR SIGNIFICANT LINKAGE TO AIRWAY OBSTRUCTION SUSCEPTIBILITY LOCI ON CHROMOSOME 8P23, THE LOCATION OF THE HUMAN DEFENSIN GENE CLUSTER. MOREOVER, A GENETIC VARIATION IN THE DEFENSIN BETA 1 (DEFB1) GENE WAS FOUND TO BE ASSOCIATED WITH COPD. THEREFORE, WE HYPOTHESIZED THAT DEFB1 IS DIFFERENTLY REGULATED AND EXPRESSED IN HUMAN LUNGS DURING COPD PROGRESSION. GENE EXPRESSION OF DEFB1 WAS ASSESSED IN BRONCHIAL EPITHELIUM AND BAL FLUID CELLS OF HEALTHY CONTROLS AND PATIENTS WITH COPD AND USING BISULFITE SEQUENCING AND CHIP ANALYSIS, THE EPIGENETIC CONTROL OF DEFB1 MRNA EXPRESSION WAS INVESTIGATED. WE CAN DEMONSTRATE THAT DEFB1 MRNA EXPRESSION WAS SIGNIFICANTLY INCREASED IN BRONCHOPULMONARY SPECIMEN OF PATIENTS WITH COPD (N = 34) VS. HEALTHY CONTROLS (N = 10) (P<0.0001). FURTHERMORE, A SIGNIFICANT CORRELATION COULD BE DETECTED BETWEEN DEFB1 AND FUNCTIONAL PARAMETERS SUCH AS FEV(1) (P = 0.0024) AND THE FEV(1)/VC RATIO (P = 0.0005). UPREGULATION OF DEFB1 MRNA WAS PARALLELED BY CHANGES IN HDAC1-3, HDAC5 AND HDAC8 MRNA EXPRESSION. WHEREAS BISULFITE SEQUENCING REVEALED NO DIFFERENCES IN THE METHYLATION STATE OF DEFB1 PROMOTER BETWEEN PATIENTS WITH COPD AND CONTROLS, CHIP ANALYSIS SHOWED THAT ENHANCED DEFB1 MRNA EXPRESSION WAS ASSOCIATED WITH THE ESTABLISHMENT OF AN ACTIVE HISTONE CODE. THUS, EXPRESSION OF HUMAN DEFB1 IS UPREGULATED AND RELATED TO THE DECREASE IN PULMONARY FUNCTION IN PATIENTS WITH COPD. 2011 8 3049 29 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 9 4023 42 LSD1-S112A EXACERBATES THE PATHOGENESIS OF CSE/LPS-INDUCED CHRONIC OBSTRUCTIVE PULMONARY DISEASE IN MICE. LYSINE-SPECIFIC DEMETHYLASE 1 (LSD1) IS AN EPIGENETIC REGULATOR THAT MODULATES THE CHROMATIN STATUS, CONTRIBUTING TO GENE ACTIVATION OR REPRESSION. THE POST-TRANSLATIONAL MODIFICATION OF LSD1 IS CRITICAL FOR THE REGULATION OF MANY OF ITS BIOLOGICAL PROCESSES. PHOSPHORYLATION OF SERINE 112 OF LSD1 BY PROTEIN KINASE C ALPHA (PKCALPHA) IS CRUCIAL FOR REGULATING INFLAMMATION, BUT ITS PHYSIOLOGICAL SIGNIFICANCE IS NOT FULLY UNDERSTOOD. THIS STUDY AIMED TO INVESTIGATE THE ROLE OF LSD1-S112A, A PHOSPHORYLATION DEFECTIVE MUTANT, IN THE CIGARETTE SMOKE EXTRACT/LPS-INDUCED CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) MODEL USING LSD1SA/SA MICE AND TO EXPLORE THE POTENTIAL MECHANISM UNDERPINNING THE DEVELOPMENT OF COPD. WE FOUND THAT LSD1SA/SA MICE EXHIBITED INCREASED SUSCEPTIBILITY TO CSE/LPS-INDUCED COPD, INCLUDING HIGH INFLAMMATORY CELL INFLUX INTO THE BRONCHOALVEOLAR LAVAGE FLUID AND AIRSPACE ENLARGEMENT. ADDITIONALLY, THE HIGH GENE EXPRESSION ASSOCIATED WITH THE INFLAMMATORY RESPONSE AND OXIDATIVE STRESS WAS OBSERVED IN CELLS AND MICE CONTAINING LSD1-S112A. SIMILAR RESULTS WERE OBTAINED FROM THE MOUSE EMBRYONIC FIBROBLASTS EXPOSED TO A PKCALPHA INHIBITOR, GO6976. THUS, THE LACK OF LSD1 PHOSPHORYLATION EXACERBATES CSE/LPS-INDUCED COPD BY ELEVATING INFLAMMATION AND OXIDATIVE STRESS. [BMB REPORTS 2021; 54(10): 522-527]. 2021 10 3718 40 INHIBITION OF BCL6B PROMOTES GASTRIC CANCER BY AMPLIFYING INFLAMMATION IN MICE. BACKGROUND: CHRONIC GASTRITIS HAS BEEN DEMONSTRATED TO BE A KEY CAUSE OF GASTRIC CANCER (GC), AND CONTROL OF GASTRIC INFLAMMATION IS REGARDED AS AN EFFECTIVE TREATMENT FOR THE CLINICAL PREVENTION OF GASTRIC CARCINOGENESIS. HOWEVER, THERE REMAINS AN UNMET NEED TO IDENTIFY THE DOMINANT REGULATORS OF GASTRIC ONCOGENESIS-ASSOCIATED INFLAMMATION IN VIVO. METHODS: THE MOUSE MODEL FOR THE STUDY OF INFLAMMATION-ASSOCIATED GC WAS INDUCED BY BENZO[A]PYRENE (BAP) INTRAGASTRIC ADMINISTRATION IN BCL6B(-/-) AND WILDTYPE MICE ON A C57BL/6 BACKGROUND. 5-AZA-2'-DEOXYCYTIDINE (5-AZA), THE DEMETHYLATION DRUG, WAS INTRAPERITONEALLY INJECTED TO RESTORE BCL6B EXPRESSION. HUMAN GC TISSUE ARRAY WAS USED TO ANALYSE PATIENT SURVIVAL BASED ON BCL6B AND CD3 PROTEIN EXPRESSION. RESULTS: BCL6B WAS GRADUALLY DOWNREGULATED BY ITS OWN PROMOTER HYPERMETHYLATION IN PARALLEL TO AN INCREASING INFLAMMATORY RESPONSE DURING THE PROGRESSION OF BAP-INDUCED GASTRIC CARCINOGENESIS IN MICE. MOREOVER, KNOCKOUT OF BCL6B DRAMATICALLY WORSENED THE SEVERITY OF GASTRIC CANCER AND AGGRAVATED THE INFLAMMATORY RESPONSE IN THE BAP-INDUCED MICE GC MODEL. RE-ACTIVATION OF BCL6B BY 5-AZA IMPEDED INFLAMMATORY AMPLIFICATION AND BAP-INDUCED GC DEVELOPMENT, PROLONGING SURVIVAL TIME IN WILDTYPE MICE, WHEREAS NO NOTABLE CURATIVE EFFECT OCCURRED IN BCL6B(-/-) MICE WITH 5-AZA TREATMENT. FINALLY, SIGNIFICANT NEGATIVE CORRELATIONS WERE DETECTED BETWEEN THE MRNA LEVELS OF BCL6B AND INFLAMMATORY CYTOKINES IN HUMAN GC TISSUES; PATIENTS HARBOURING BCL6B-NEGETIVE AND SEVERE-INFLAMMATION GC TUMOURS WERE FOUND TO EXHIBIT THE SHORTEST SURVIVAL TIME. CONCLUSIONS: EPIGENETIC INACTIVATION OF BCL6B PROMOTES GASTRIC CANCER THROUGH AMPLIFICATION OF THE GASTRIC INFLAMMATORY RESPONSE IN VIVO AND OFFERS A NEW APPROACH FOR GC TREATMENT AND REGENERATIVE MEDICINE. 2019 11 6294 26 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 12 197 42 ACINAR ATP8B1/LPC PATHWAY PROMOTES MACROPHAGE EFFEROCYTOSIS AND CLEARANCE OF INFLAMMATION DURING CHRONIC PANCREATITIS DEVELOPMENT. NONINFLAMMATORY CLEARANCE OF DYING CELLS BY PROFESSIONAL PHAGOCYTES, TERMED EFFEROCYTOSIS, IS FUNDAMENTAL IN BOTH HOMEOSTASIS AND INFLAMMATORY FIBROSIS DISEASE BUT HAS NOT BEEN CONFIRMED TO OCCUR IN CHRONIC PANCREATITIS (CP). HERE, WE INVESTIGATED WHETHER EFFEROCYTOSIS CONSTITUTES A NOVEL REGULATORY TARGET IN CP AND ITS MECHANISMS. PRSS1 TRANSGENIC (PRSS1(TG)) MICE WERE TREATED WITH CAERULEIN TO MIMIC CP DEVELOPMENT. PHOSPHOLIPID METABOLITE PROFILING AND EPIGENETIC ASSAYS WERE PERFORMED WITH PRSS1(TG) CP MODELS. THE POTENTIAL FUNCTIONS OF ATP8B1 IN CP MODEL WERE CLARIFIED USING ATP8B1-OVEREXPRESSING ADENO-ASSOCIATED VIRUS, IMMUNOFLUORESCENCE, ENZYME-LINKED IMMUNOSORBENT ASSAY(ELISA), AND LIPID METABOLOMIC APPROACHES. ATAC-SEQ COMBINED WITH RNA-SEQ WAS THEN USED TO IDENTIFY TRANSCRIPTION FACTORS BINDING TO THE ATP8B1 PROMOTER, AND CHIP-QPCR AND LUCIFERASE ASSAYS WERE USED TO CONFIRM THAT THE IDENTIFIED TRANSCRIPTION FACTOR BOUND TO THE ATP8B1 PROMOTER, AND TO IDENTIFY THE SPECIFIC BINDING SITE. FLOW CYTOMETRY WAS PERFORMED TO ANALYZE THE PROPORTION OF PANCREATIC MACROPHAGES. DECREASED EFFEROCYTOSIS WITH AGGRAVATED INFLAMMATION WAS IDENTIFIED IN CP. THE LYSOPHOSPHATIDYLCHOLINE (LPC) PATHWAY WAS THE MOST OBVIOUSLY DYSREGULATED PHOSPHOLIPID PATHWAY, AND LPC AND ATP8B1 EXPRESSION GRADUALLY DECREASED DURING CP DEVELOPMENT. H3K27ME3 CHIP-SEQ SHOWED THAT INCREASED ATP8B1 PROMOTER METHYLATION LED TO TRANSCRIPTIONAL INHIBITION. ATP8B1 COMPLEMENTATION SUBSTANTIALLY INCREASED THE LPC CONCENTRATION AND IMPROVED CP OUTCOMES. BHLHA15 WAS IDENTIFIED AS A TRANSCRIPTION FACTOR THAT BINDS TO THE ATP8B1 PROMOTER AND REGULATES PHOSPHOLIPID METABOLISM. OUR STUDY INDICATES THAT THE ACINAR ATP8B1/LPC PATHWAY ACTS AS AN IMPORTANT "FIND-ME" SIGNAL FOR MACROPHAGES AND PLAYS A PROTECTIVE ROLE IN CP, WITH ATP8B1 TRANSCRIPTION PROMOTED BY THE ACINAR CELL-SPECIFIC TRANSCRIPTION FACTOR BHLHA15. BHLHA15, ATP8B1, AND LPC COULD BE CLINICALLY TRANSLATED INTO VALUABLE THERAPEUTIC TARGETS TO OVERCOME THE LIMITATIONS OF CURRENT CP THERAPIES. 2022 13 2032 33 EPIGENETIC CHANGES IN P21 EXPRESSION IN RENAL CELLS AFTER EXPOSURE TO BROMATE. THIS STUDY TESTED THE HYPOTHESIS THAT BROMATE (KBRO3)-INDUCED RENAL CELL DEATH IS MEDIATED BY EPIGENETIC MECHANISMS. GLOBAL DNA METHYLATION, AS ASSESSED BY 5-METHYLCYTOSINE STAINING, WAS NOT CHANGED IN NORMAL RAT KIDNEY CELLS TREATED WITH ACUTE CYTOTOXIC DOSES OF KBRO3 (100 AND 200 PPM), AS COMPARED WITH CONTROLS. HOWEVER, KBRO3 TREATMENT DID INCREASE P38, P53 AND HISTONE 2AX (H2AX) PHOSPHORYLATION, AND P21 EXPRESSION. TREATMENT OF CELLS WITH INHIBITORS OF DNA METHYLTRANSFERASE (5-AZACYTIDINE OR 5-AZA) AND HISTONE DEACETYLASE (TRICHOSTATIN A OR TSA) IN ADDITION TO KBRO3 INCREASED CYTOTOXICITY, AS COMPARED WITH CELLS EXPOSED TO KBRO3 ALONE. 5-AZA AND TSA CO-TREATMENT DID NOT ALTER P38 OR P53 PHOSPHORYLATION, BUT SLIGHTLY DECREASED H2AX PHOSPHORYLATION AND SIGNIFICANTLY DECREASED P21 EXPRESSION. WE ALSO ASSESSED EPIGENETIC CHANGES IN CELLS TREATED UNDER SUB-CHRONIC CONDITIONS WITH ENVIRONMENTALLY RELEVANT CONCENTRATIONS OF KBRO3. UNDER THESE CONDITIONS (0-10PPM KBRO3 FOR UP TO 18 DAYS), WE DETECTED NO INCREASES IN CELL DEATH OR DNA DAMAGE. IN CONTRAST, SLIGHT ALTERATIONS WERE DETECTED IN THE PHOSPHORYLATION OF H2AX, P38, AND P53. SUB-CHRONIC LOW-DOSE KBRO3 TREATMENT ALSO INDUCED A BIPHASIC RESPONSE IN P21 EXPRESSION, WITH LOWER CONCENTRATIONS INCREASING EXPRESSION, BUT HIGHER CONCENTRATIONS DECREASING EXPRESSION. METHYLATION-SPECIFIC PCR DEMONSTRATED THAT SUB-CHRONIC KBRO3 TREATMENT ALTERED THE METHYLATION OF CYTOSINE BASES IN THE P21 GENE, AS COMPARED WITH CONTROLS, CORRELATING TO ALTERATIONS IN P21 PROTEIN EXPRESSION. COLLECTIVELY, THESE DATA SHOW THE NOVEL FINDING THAT KBRO3-INDUCED RENAL CELL DEATH IS ALTERED BY INHIBITORS OF EPIGENETIC MODIFYING ENZYMES AND THAT KBRO3 ITSELF INDUCES EPIGENETIC CHANGES IN THE P21 GENE. 2014 14 26 35 A 6-ALKYLSALICYLATE HISTONE ACETYLTRANSFERASE INHIBITOR INHIBITS HISTONE ACETYLATION AND PRO-INFLAMMATORY GENE EXPRESSION IN MURINE PRECISION-CUT LUNG SLICES. LYSINE ACETYLATIONS ARE POST-TRANSLATIONAL MODIFICATIONS OF CELLULAR PROTEINS, THAT ARE CRUCIAL IN THE REGULATION OF MANY CELLULAR PROCESSES. LYSINE ACETYLATIONS ON HISTONE PROTEINS ARE PART OF THE EPIGENETIC CODE REGULATING GENE EXPRESSION AND ARE INSTALLED BY HISTONE ACETYLTRANSFERASES. OBSERVATIONS THAT INFLAMMATORY LUNG DISEASES, SUCH AS ASTHMA AND CHRONIC OBSTRUCTIVE PULMONARY DISEASE, ARE CHARACTERIZED BY INCREASED HISTONE ACETYLTRANSFERASE ACTIVITY INDICATE THAT DEVELOPMENT OF SMALL MOLECULE INHIBITORS FOR THESE ENZYMES MIGHT BE A VALUABLE APPROACH TOWARDS NEW THERAPIES FOR THESE DISEASES. THE 6-ALKYLSALICYLATE MG149 IS A CANDIDATE TO EXPLORE THIS HYPOTHESIS BECAUSE IT HAS BEEN DEMONSTRATED TO INHIBIT THE MYST TYPE HISTONE ACETYLTRANSFERASES. IN THIS STUDY, WE DETERMINED THE K(I) VALUE FOR INHIBITION OF THE MYST TYPE HISTONE ACETYLTRANSFERASE KAT8 BY MG149 TO BE 39 +/- 7.7 MUM. UPON INVESTIGATING WHETHER THE INHIBITION OF HISTONE ACETYLTRANSFERASES BY MG149 CORRELATES WITH INHIBITION OF HISTONE ACETYLATION IN MURINE PRECISION-CUT LUNG SLICES, INHIBITION OF ACETYLATION WAS OBSERVED USING AN LC-MS/MS BASED ASSAY ON HISTONE H4 RES 4-17, WHICH CONTAINS THE TARGET LYSINE OF KAT8. FOLLOWING UP ON THIS, UPON TREATMENT WITH MG149, REDUCED PRO-INFLAMMATORY GENE EXPRESSION WAS OBSERVED IN LIPOPOLYSACCHARIDE AND INTERFERON GAMMA STIMULATED MURINE PRECISION-CUT LUNG SLICES. BASED ON THIS, WE PROPOSE THAT 6-ALKYLSALICYLATES SUCH AS MG149 HAVE POTENTIAL FOR DEVELOPMENT TOWARDS APPLICATIONS IN THE TREATMENT OF INFLAMMATORY LUNG DISEASES. 2017 15 4873 50 OVER-EXPRESSION OF PROTHYMOSIN-ALPHA ANTAGONIZES TGFBETA SIGNALLING TO PROMOTE THE DEVELOPMENT OF EMPHYSEMA. EMPHYSEMA, A MAJOR CONSEQUENCE OF CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD), IS CHARACTERIZED BY THE PERMANENT AIRFLOW RESTRICTION RESULTING FROM ENLARGEMENT OF ALVEOLAR AIRSPACE AND LOSS OF LUNG ELASTICITY. TRANSFORMING GROWTH FACTOR-BETA (TGFBETA) SIGNALLING REGULATES THE BALANCE OF MATRIX METALLOPROTEINASE (MMP)/TISSUE INHIBITOR OF MATRIX METALLOPROTEINASE (TIMP) TO CONTROL MATRIX HOMEOSTASIS. PATIENTS WITH COPD HAVE DYSREGULATED TGFBETA SIGNALLING AND REDUCED HISTONE DEACETYLASE (HDAC) ACTIVITY THROUGH EPIGENETIC UP-REGULATION OF HISTONE ACETYLATION IN THE PROMOTERS OF PRO-INFLAMMATORY GENES. HOWEVER, THE POTENTIAL LINK BETWEEN DECREASED HDAC ACTIVITY AND DYSREGULATED TGFBETA SIGNALLING IN EMPHYSEMA PATHOGENESIS REMAINS TO BE DETERMINED. PROTHYMOSIN ALPHA (PROT), A HIGHLY CONSERVED ACIDIC NUCLEAR PROTEIN, PLAYS A ROLE IN THE ACETYLATION OF HISTONE AND NON-HISTONE PROTEINS. THE AIM OF THIS STUDY WAS TO TEST THE HYPOTHESIS THAT PROT INHIBITS TGFBETA-SMAD SIGNALLING THROUGH SMAD7, THEREBY CONTRIBUTING TO EMPHYSEMA PATHOGENESIS. WE SHOW THAT PROT ENHANCES SMAD7 ACETYLATION BY DECREASING ITS ASSOCIATION WITH HDAC AND THEREBY DOWN-REGULATES TGFBETA-SMAD SIGNALLING. PROT CAUSED AN IMBALANCE BETWEEN MMP AND TIMP THROUGH ACETYLATED SMAD7 IN FAVOUR OF MMP EXPRESSION. IN ADDITION TO INTERFERING WITH R-SMAD ACTIVATION AND TARGETING RECEPTORS FOR DEGRADATION IN THE CYTOPLASM, ACETYLATED SMAD7 POTENTIATED BY PROT COMPETITIVELY ANTAGONIZED BINDING OF THE PSMAD2/3-SMAD4 COMPLEX TO THE TIMP-3 PROMOTER, RESULTING IN REDUCED TIMP-3 EXPRESSION. THESE EFFECTS WERE DETECTED IN PROT-OVER-EXPRESSING CELLS, LUNGS OF PROT TRANSGENIC MICE DISPLAYING AN EMPHYSEMA PHENOTYPE AND IN EMPHYSEMA PATIENTS. IMPORTANTLY, INCREASED SMAD7 AND REDUCED TIMP-3 WERE FOUND IN THE LUNGS OF EMPHYSEMA PATIENTS AND MICE WITH CIGARETTE SMOKE EXTRACT (CSE)-INDUCED EMPHYSEMA. SUCH EFFECTS COULD BE ABROGATED BY SILENCING ENDOGENOUS PROT EXPRESSION. COLLECTIVELY, OUR RESULTS UNCOVER ACETYLATED SMAD7 REGULATED BY PROT AS AN IMPORTANT DETERMINANT IN DYSREGULATED TGFBETA SIGNALLING THAT CONTRIBUTES TO EMPHYSEMA PATHOGENESIS. 2016 16 272 38 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 17 2453 30 EPIGENETIC SUPPRESSION OF THE IMMUNOREGULATOR MZB1 IS ASSOCIATED WITH THE MALIGNANT PHENOTYPE OF GASTRIC CANCER. PREDICTION OF TUMOR RECURRENCE AFTER CURATIVE RESECTION IS CRITICAL FOR DETERMINING THE PROGNOSIS OF PATIENTS WITH GASTRIC CANCER (GC). THE INITIATION AND PROGRESSION OF GC ARE ASSOCIATED WITH INAPPROPRIATE IMMUNE RESPONSES CAUSED BY CHRONIC INFLAMMATION OF THE GASTRIC MUCOSA. TO IDENTIFY IMMUNOREGULATORY MOLECULES INVOLVED IN GC PROGRESSION, GC CELL LINES AND 200 PAIRS OF TUMOR AND NORMAL TISSUES FROM PATIENTS WITH GC WERE ANALYZED FOR GENE EXPRESSION, AMPLIFICATION AND METHYLATION AS WELL AS FUNCTION OF A DIFFERENTIALLY EXPRESSED GENE. THE TRANSCRIPTOME ANALYSIS REVEALED THAT MARGINAL ZONE B AND B1 CELL SPECIFIC PROTEIN (MZB1) WAS EXPRESSED AT SIGNIFICANTLY DECREASED LEVELS IN PRIMARY GC TISSUES WHEN COMPARED WITH THE CORRESPONDING NORMAL GASTRIC MUCOSA. PCR ARRAY ANALYSIS EXPLORING GENES EXPRESSED COOPERATIVELY WITH MZB1 REVEALED THAT DIFFERENTIAL EXPRESSION OF MZB1 MRNA IN GC CELL LINES CORRELATED POSITIVELY WITH THE LEVELS OF THE MRNAS ENCODING ESTROGEN RECEPTOR 1 AND DESUMOYLATING ISOPEPTIDASE 1. HYPERMETHYLATION OF THE MZB1 PROMOTER WAS FREQUENT IN CELL LINES WITH DECREASED LEVELS OF MZB1 MRNA. SIRNA-MEDIATED KNOCKDOWN OF MZB1 SIGNIFICANTLY INCREASED PROLIFERATION, INVASION AND MIGRATION OF GC CELL LINES. LOW MZB1 EXPRESSION WAS AN INDEPENDENT PROGNOSTIC FACTOR FOR RECURRENCE AFTER CURATIVE GASTRECTOMY AND WAS ASSOCIATED SIGNIFICANTLY WITH INCREASED HEMATOGENOUS RECURRENCE. MZB1 ACTS AS A SUPPRESSOR OF GC. LOW MZB1 EXPRESSION IN THE PRIMARY GC TISSUE IS PREDICTIVE OF RECURRENCE AFTER CURATIVE RESECTION. 2016 18 2432 33 EPIGENETIC SILENCING OF MIR-708 ENHANCES NF-KAPPAB SIGNALING IN CHRONIC LYMPHOCYTIC LEUKEMIA. MICRORNAS (MIRNAS) ARE POST-TRANSCRIPTIONAL REGULATORS OF GENE EXPRESSION AND THEIR DEREGULATION IS INVOLVED IN TUMOR DEVELOPMENT. EPIGENETIC GENE SILENCING IN CANCER BY DNA METHYLATION CONTRIBUTES TO THE SILENCING OF TUMOR-SUPPRESSOR GENES, INCLUDING MIRNAS. WE HAVE RECENTLY SHOWN THAT THE PROMOTER OF MIR-708 IS ABERRANTLY METHYLATED IN CHRONIC LYMPHOCYTIC LEUKEMIA (CLL). TO CHARACTERIZE THE MOLECULAR SIGNALING NETWORKS THAT ARE INFLUENCED BY MIR-708, WE PERFORMED A LUCIFERASE-BASED SCREEN EVALUATING THE EFFECTS OF ECTOPIC MIR-708 EXPRESSION ON LEUKEMIA-RELEVANT SIGNALING PATHWAYS. WE FOUND THAT MIR-708 STRONGLY REPRESSED NF-KAPPAB SIGNALING, A PATHWAY KNOWN TO BE DEREGULATED IN CLL. AMONG THE PREDICTED MIR-708 TARGETS WAS IKKBETA (INHIBITOR OF KAPPA LIGHT POLYPEPTIDE GENE ENHANCER IN B CELLS, KINASE-BETA/IKBKB), A KEY KINASE FACILITATING NF-KAPPAB SIGNALING. WE VALIDATED THE INTERACTION OF MIR-708 WITH THE 3'-UNTRANSLATED REGION OF IKKBETA AND FOUND THAT MIR-708 OVEREXPRESSION REPRESSES ENDOGENOUS IKKBETA. PHOSPHORYLATION OF THE IKKBETA TARGET IKAPPABALPHA AND EXPRESSION OF KNOWN NF-KAPPAB TARGET GENES WERE IMPAIRED BY MIR-708. FURTHERMORE, WE IDENTIFIED AN ENHANCER REGION DOWNSTREAM OF THE MIR-708 PROMOTER THAT DISPLAYS A DISTINCT DNA METHYLATION STATUS IN CLL. HIGH ENHANCER METHYLATION IS SIGNIFICANTLY CORRELATED WITH LOWER MIR-708 EXPRESSION AND IS PREDOMINANTLY FOUND IN PATIENTS WITH POOR PROGNOSIS AND SHORTER TIME TO TREATMENT. THESE RESULTS DEMONSTRATE THAT MIR-708 REGULATES THE NF-KAPPAB PATHWAY BY TARGETING IKKBETA, AND THAT METHYLATION OF A KEY ENHANCER REGION CONTRIBUTES TO ITS SUPPRESSION IN CLL. 2015 19 1334 35 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 20 136 32 ABERRANT DNA HYPERMETHYLATION PATTERNS LEAD TO TRANSCRIPTIONAL SILENCING OF TUMOR SUPPRESSOR GENES IN UVB-EXPOSED SKIN AND UVB-INDUCED SKIN TUMORS OF MICE. OVEREXPOSURE OF THE HUMAN SKIN TO SOLAR ULTRAVIOLET (UV) RADIATION IS THE MAJOR ETIOLOGIC FACTOR FOR DEVELOPMENT OF SKIN CANCERS. HERE, WE REPORT THE RESULTS OF EPIGENETIC MODIFICATIONS IN UV-EXPOSED SKIN AND SKIN TUMORS IN A SYSTEMATIC MANNER. THE SKIN AND TUMOR SAMPLES WERE COLLECTED AFTER CHRONIC EXPOSURE OF THE SKIN OF SKH-1 HAIRLESS MICE TO UVB RADIATION USING A WELL-ESTABLISHED PHOTOCARCINOGENESIS PROTOCOL. WE FOUND A DISTINCT DNA HYPERMETHYLATION PATTERN IN THE UVB-EXPOSED EPIDERMAL SKIN AND UVB-INDUCED SKIN TUMORS THAT WAS ASSOCIATED WITH THE ELEVATED EXPRESSION AND ACTIVITY OF THE DNA METHYLTRANSFERASES (DNMT) 1, DNMT3A AND DNMT3B. TO EXPLORE THE ROLE OF HYPERMETHYLATION IN SKIN PHOTOCARCINOGENESIS, WE FOCUSED ON THE P16(INK4A) AND RASSF1A TUMOR SUPPRESSOR GENES, WHICH ARE TRANSCRIPTIONALLY SILENCED ON METHYLATION. WE ESTABLISHED THAT THE SILENCING OF THESE GENES IN UVB-EXPOSED EPIDERMIS AND UVB-INDUCED SKIN TUMORS IS ASSOCIATED WITH A NETWORK OF EPIGENETIC MODIFICATIONS, INCLUDING HYPOACETYLATION OF HISTONE H3 AND H4 AND INCREASED HISTONE DEACETYLATION, AS WELL AS RECRUITMENT OF METHYL-BINDING PROTEINS, INCLUDING MECP2 AND MBD1, TO THE METHYLATED CPGS. HIGHER LEVELS OF DNA METHYLATION AND DNMT ACTIVITY IN HUMAN SQUAMOUS CELL CARCINOMA SPECIMENS THAN IN NORMAL HUMAN SKIN SUGGEST THAT THE DATA ARE RELEVANT CLINICALLY. OUR DATA INDICATE FOR THE FIRST TIME THAT UVB-INDUCED DNA HYPERMETHYLATION, ENHANCED DNMT ACTIVITY AND HISTONE MODIFICATIONS OCCUR IN UVB-EXPOSED SKIN AND UVB-INDUCED SKIN TUMORS AND SUGGEST THAT THESE EVENTS ARE INVOLVED IN THE SILENCING OF TUMOR SUPPRESSOR GENES AND IN SKIN TUMOR DEVELOPMENT. 2011