1 4697 146 NF-KAPPAB UPREGULATION THROUGH EPIGENETIC SILENCING OF LDOC1 DRIVES TUMOR BIOLOGY AND SPECIFIC IMMUNOPHENOTYPE IN GROUP A EPENDYMOMA. BACKGROUND: INFLAMMATION HAS BEEN IDENTIFIED AS A HALLMARK OF HIGH-RISK GROUP A (GPA) EPENDYMOMA (EPN). CHRONIC INTERLEUKIN (IL)-6 SECRETION FROM GPA TUMORS DRIVES AN IMMUNE SUPPRESSIVE PHENOTYPE BY POLARIZING INFILTRATING MONOCYTES. THIS STUDY DETERMINES THE MECHANISM BY WHICH IL-6 IS DYSREGULATED IN GPA EPN. METHODS: TWENTY PEDIATRIC GPA AND 21 PEDIATRIC GROUP B (GPB) EPN HAD GENE SET ENRICHMENT ANALYSIS FOR MSIGDB HALLMARK GENE SETS PERFORMED. PROTEIN AND RNA FROM PATIENTS AND CELL LINES WERE USED TO VALIDATE TRANSCRIPTOMIC FINDINGS. GPA CELL LINES 811 AND 928 WERE USED FOR IN VITRO EXPERIMENTS PERFORMED IN THIS STUDY. RESULTS: THE NUCLEAR FACTOR-KAPPAB (NF-KAPPAB) PATHWAY IS A MASTER REGULATOR OF IL-6 AND A SIGNALING PATHWAY ENRICHED IN GPA COMPARED WITH GPB EPN. KNOCKDOWN OF NF-KAPPAB LED TO SIGNIFICANT DOWNREGULATION OF IL-6 IN 811 AND 928. NF-KAPPAB ACTIVATION WAS INDEPENDENT OF TUMOR NECROSIS FACTOR ALPHA (TNF-ALPHA) STIMULATION IN BOTH CELL LINES, SUGGESTING THAT NF-KAPPAB HYPERACTIVATION IS MEDIATED THROUGH AN ALTERNATIVE MECHANISM. LEUCINE ZIPPER DOWNREGULATED IN CANCER 1 (LDOC1) IS A KNOWN TRANSCRIPTIONAL REPRESSOR OF NF-KAPPAB. IN MANY CANCERS, LDOC1 PROMOTER IS METHYLATED, WHICH INHIBITS GENE TRANSCRIPTION. WE FOUND DECREASED LDOC1 GENE EXPRESSION IN GPA COMPARED WITH GPB EPN, AND IN OTHER PEDIATRIC BRAIN TUMORS. EPN CELLS TREATED WITH 5AZA-DC, DEMETHYLATED LDOC1 REGULATORY REGIONS, UPREGULATED LDOC1 EXPRESSION, AND CONCOMITANTLY DECREASED IL-6 SECRETION. STABLE KNOCKDOWN OF LDOC1 IN EPN CELL LINES RESULTED IN A SIGNIFICANT INCREASE IN GENE TRANSCRIPTION OF V-REL AVIAN RETICULOENDOTHELIOSIS VIRAL ONCOGENE HOMOLOG A, WHICH CORRELATED TO AN INCREASE IN NF-KAPPAB TARGET GENES. CONCLUSION: THESE RESULTS SUGGEST THAT EPIGENETIC SILENCING OF LDOC1 IN GPA EPN REGULATES TUMOR BIOLOGY AND DRIVES INFLAMMATORY IMMUNE PHENOTYPE. 2017 2 4696 36 NF-KAPPAB REPRESSES RETINOIC ACID RECEPTOR-MEDIATED GPRC5A TRANSACTIVATION IN LUNG EPITHELIAL CELLS TO PROMOTE NEOPLASIA. CHRONIC INFLAMMATION IS ASSOCIATED WITH LUNG TUMORIGENESIS, IN WHICH NF-KAPPAB-MEDIATED EPIGENETIC REGULATION PLAYS A CRITICAL ROLE. LUNG TUMOR SUPPRESSOR G PROTEIN-COUPLED RECEPTOR, FAMILY C, MEMBER 5A (GPRC5A), IS REPRESSED IN MOST NON-SMALL CELL LUNG CANCER (NSCLC); HOWEVER, THE MECHANISMS REMAIN UNCLEAR. HERE, WE SHOW THAT NF-KAPPAB ACTS AS A TRANSCRIPTIONAL REPRESSOR IN SUPPRESSION OF GPRC5A. NF-KAPPAB INDUCED GPRC5A REPRESSION BOTH IN VITRO AND IN VIVO. INTRIGUINGLY, TRANSACTIVATION OF NF-KAPPAB DOWNSTREAM TARGETS WAS NOT REQUIRED, BUT THE TRANSACTIVATION DOMAIN OF RELA/P65 WAS REQUIRED FOR GPRC5A REPRESSION. NF-KAPPAB DID NOT BIND TO ANY POTENTIAL CIS-ELEMENT IN THE GPRC5A PROMOTER. INSTEAD, P65 WAS COMPLEXED WITH RETINOIC ACID RECEPTOR ALPHA/BETA (RARALPHA/BETA) AND RECRUITED TO THE RA RESPONSE ELEMENT SITE AT THE GPRC5A PROMOTER, RESULTING IN DISRUPTED RNA POLYMERASE II COMPLEXING AND SUPPRESSED TRANSCRIPTION. NOTABLY, PHOSPHORYLATION ON SERINE 276 OF P65 WAS REQUIRED FOR INTERACTION WITH RARALPHA/BETA AND REPRESSION OF GPRC5A. MOREOVER, NF-KAPPAB-MEDIATED EPIGENETIC REPRESSION WAS THROUGH SUPPRESSION OF ACETYLATED HISTONE H3K9 (H3K9AC), BUT NOT DNA METHYLATION OF THE CPG ISLANDS, AT THE GPRC5A PROMOTER. CONSISTENTLY, A HISTONE DEACETYLASE INHIBITOR, BUT NOT DNA METHYLATION INHIBITOR, RESTORED GPRC5A EXPRESSION IN NSCLC CELLS. THUS, NF-KAPPAB INDUCES TRANSCRIPTIONAL REPRESSION OF GPRC5A VIA A COMPLEX WITH RARALPHA/BETA AND MEDIATES EPIGENETIC REPRESSION VIA SUPPRESSION OF H3K9AC. 2023 3 1950 36 EPIGENETIC ACTIVATION OF TENSIN 4 PROMOTES GASTRIC CANCER PROGRESSION. GASTRIC CANCER (GC) IS A COMPLEX DISEASE INFLUENCED BY MULTIPLE GENETIC AND EPIGENETIC FACTORS. CHRONIC INFLAMMATION CAUSED BY HELICOBACTER PYLORI INFECTION AND DIETARY RISK FACTORS CAN RESULT IN THE ACCUMULATION OF ABERRANT DNA METHYLATION IN GASTRIC MUCOSA, WHICH PROMOTES GC DEVELOPMENT. TENSIN 4 (TNS4), A MEMBER OF THE TENSIN FAMILY OF PROTEINS, IS LOCALIZED TO FOCAL ADHESION SITES, WHICH CONNECT THE EXTRACELLULAR MATRIX AND CYTOSKELETAL NETWORK. WE IDENTIFIED UPREGULATION OF TNS4 IN GC USING QUANTITATIVE REVERSE TRANSCRIPTION PCR WITH 174 PAIRED SAMPLES OF GC TUMORS AND ADJACENT NORMAL TISSUES. TRANSCRIPTIONAL ACTIVATION OF TNS4 OCCURRED EVEN DURING THE EARLY STAGE OF TUMOR DEVELOPMENT. TNS4 DEPLETION IN GC CELL LINES THAT EXPRESSED HIGH TO MODERATE LEVELS OF TNS4, I.E., SNU-601, KATO III, AND MKN74, REDUCED CELL PROLIFERATION AND MIGRATION, WHEREAS ECTOPIC EXPRESSION OF TNS4 IN THOSE LINES THAT EXPRESSED LOWER LEVELS OF TNS4, I.E., SNU-638, MKN1, AND MKN45 INCREASED COLONY FORMATION AND CELL MIGRATION. THE PROMOTER REGION OF TNS4 WAS HYPOMETHYLATED IN GC CELL LINES THAT SHOWED UPREGULATION OF TNS4. WE ALSO FOUND A SIGNIFICANT NEGATIVE CORRELATION BETWEEN TNS4 EXPRESSION AND CPG METHYLATION IN 250 GC TUMORS BASED ON THE CANCER GENOME ATLAS (TCGA) DATA. THIS STUDY ELUCIDATES THE EPIGENETIC MECHANISM OF TNS4 ACTIVATION AND FUNCTIONAL ROLES OF TNS4 IN GC DEVELOPMENT AND PROGRESSION AND SUGGESTS A POSSIBLE APPROACH FOR FUTURE GC TREATMENTS. 2023 4 3128 54 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 1067 44 CLINICAL UTILITY OF PDSS2 EXPRESSION TO STRATIFY PATIENTS AT RISK FOR RECURRENCE OF HEPATOCELLULAR CARCINOMA. IDENTIFICATION OF NOVEL GENETIC AND EPIGENETIC ALTERATIONS IS REQUIRED FOR OPTIMAL STRATIFICATION OF PATIENTS WITH HEPATOCELLULAR CARCINOMA (HCC) AT RISK FOR RECURRENCE AND ADVERSE PROGNOSIS. COENZYME Q10 (COQ10), WHICH MEDIATES APOPTOSIS, IS SYNTHESIZED BY PRENYL DIPHOSPHATE SYNTHASE SUBUNIT 2 (PDSS2). IN THE PRESENT STUDY WE EVALUATED THE CLINICAL SIGNIFICANCE AND REGULATORY MECHANISMS OF PDSS2 EXPRESSION IN HCC. PDSS2 EXPRESSION LEVELS AND THOSE OF GENES ENCODING POTENTIALLY INTERACTING PROTEINS AS WELL AS THE METHYLATION STATUS OF THE PDSS2 PROMOTER REGION WERE ANALYZED IN HCC CELL LINES. PDSS2 MRNA LEVELS IN 151 PAIRS OF RESECTED SPECIMENS WERE DETERMINED TO EVALUATE THE ASSOCIATION OF PDSS2 EXPRESSION AND CLINICOPATHOLOGICAL FACTORS. THE EXPRESSION AND DISTRIBUTION OF PDSS2 WERE DETERMINED USING IMMUNOHISTOCHEMISTRY. PDSS2 MRNA EXPRESSION WAS DECREASED IN SIX OF NINE HCC CELL LINES AND SIGNIFICANTLY CORRELATED WITH THOSE OF HEPATOCYTE NUCLEAR FACTOR 4ALPHA. PDSS2 TRANSCRIPTION IN HCC CELLS WITH DECREASED PDSS2 EXPRESSION ACCOMPANYING HYPERMETHYLATION WAS REACTIVATED AFTER TREATING THESE CELLS WITH A METHYLATION INHIBITOR. MEAN EXPRESSION LEVELS OF PDSS2 MRNA RELATIVE TO THAT OF UNINVOLVED LIVER DIMINISHED GRADUALLY IN THE ORDER OF CHRONIC HEPATITIS TO CIRRHOSIS, AND EACH WAS SIGNIFICANTLY HIGHER THAN THOSE OF HCCS. PDSS2 AND PDSS2 MRNA LEVELS WERE CONSISTENT. DECREASED PDSS2 MRNA LEVELS WERE DETECTED IN HCC TISSUES OF 56 PATIENTS, CORRELATED WITH SHORTER DISEASE-SPECIFIC SURVIVAL, AND WAS IDENTIFIED AS AN INDEPENDENT PROGNOSTIC FACTOR. PDSS2 IS A PUTATIVE TUMOR SUPPRESSOR, AND PROMOTER HYPERMETHYLATION IS A KEY REGULATORY MECHANISM IN HCC. DECREASED LEVELS OF PDSS2 MRNA EXPRESSION MAY REPRESENT A NOVEL BIOMARKER OF HCC. 2014 6 1843 38 EFFECTS OF TELOMERASE INHIBITOR ON EPIGENETIC CHROMATIN MODIFICATION ENZYMES IN MALIGNANCIES. TELOMERASE HAS A CRITICAL ROLE IN CELL PROLIFERATION, TUMOR MAINTAINING, AND THERAPY RESISTANCE, WHICH ACT BY MODIFYING MANY SIGNALING PATHWAYS. 2-[(E)-3-NAPHTALEN-2-YL-BUT-2-ENOYLAMINO]-BENZOIC ACID (BIBR1532) IS ONE OF THE MOST STUDIED TELOMERASE INHIBITORS, AND IT TARGETS TELOMERASE COMPONENTS TERC AND TERT. IN THIS NOVEL STUDY, WE AIMED TO INVESTIGATE THE EPIGENETIC EFFECTS OF BIBR1532 ON BOTH HEMATOLOGIC MALIGNANCIES AND SOLID TUMORS. K-562 HUMAN CHRONIC MYELOID LEUKEMIA CELL LINE AND U87MG GLIOBLASTOMA CELL LINE WERE COMPARED WITH CONTROL GROUPS WITHOUT BIBR1532 TREATMENT. CYTOTOXIC EFFECTS OF BIBR1532 WERE DETERMINED BY USING WST-1 ASSAY. APOPTOTIC EFFECTS OF BIBR1532 WERE DETECTED BY USING ANNEXIN V METHOD. TO ASSESS EXPRESSION CHANGES IN THE HUMAN EPIGENETIC CHROMATIN MODIFICATION ENZYME GENES, TOTAL RNA WAS ISOLATED FROM K-562 AND U87MG CELLS TREATED WITH BIBR1532 AND UNTREATED CONTROL CELLS. BIBR1532 INDUCED 2.41-FOLD APOPTOTIC CELL DEATH IN U87MG CELL LINES COMPARED WITH CONTROL GROUPS. APOPTOSIS WAS SLIGHTLY INDUCED IN K-562 CELLS WITH BIBR1532 TREATMENT COMPARED WITH CONTROL CELLS. WE OBSERVED THAT BIBR1532 ALSO REGULATES SIMILAR GENES IN BOTH CELL LINES, AND IT IS USEFUL ON EPIGENETIC MECHANISMS. AS A RESULT, TELOMERASE INHIBITOR BIBR1532 HAS A SIGNIFICANT EFFECT ON BOTH HEMATOLOGICAL MALIGNANCIES AND SOLID TUMORS. 2018 7 1298 36 DECREASED NUCLEAR RECEPTOR ACTIVITY AND EPIGENETIC MODULATION ASSOCIATES WITH DOWN-REGULATION OF HEPATIC DRUG-METABOLIZING ENZYMES IN CHRONIC KIDNEY DISEASE. PATIENTS WITH CHRONIC KIDNEY DISEASE (CKD) REQUIRE MANY MEDICATIONS. CYP2C AND CYP3A DRUG-METABOLIZING ENZYMES PLAY A CRITICAL ROLE IN DETERMINING THE PHARMACOKINETICS OF THE MAJORITY OF PRESCRIBED MEDICATIONS. THESE ENZYMES ARE TRANSCRIPTIONALLY REGULATED BY THE NUCLEAR RECEPTORS PREGNANE X RECEPTOR (PXR) AND HEPATIC NUCLEAR FACTOR 4ALPHA (HNF-4ALPHA). EXPRESSION OF CYP2C AND CYP3A IS DECREASED IN CKD; HOWEVER, THE MECHANISMS BY WHICH THIS OCCURS IS UNKNOWN. WE INDUCED CKD IN RATS BY 5/6 NEPHRECTOMY AND USED CHROMATIN IMMUNOPRECIPITATION (CHIP) TO DETERMINE NUCLEAR RECEPTOR- AND EPIGENETIC ALTERATION-MEDIATED DIFFERENCES IN THE PROMOTER REGION OF THE CYP2C AND CYP3A GENES. RNA POLYMERASE II AND HNF-4ALPHA BINDING WAS DECREASED 76 AND 57% IN THE CYP2C11 PROMOTOR AND 71 AND 77% IN THE CYP3A2 PROMOTER, RESPECTIVELY (P<0.05). CHIP ALSO REVEALED A 57% DECREASE IN PXR BINDING TO THE CYP3A2 PROMOTER IN CKD RATS (P<0.05). THE DECREASE IN PXR AND HNF-4ALPHA BINDING WAS ACCOMPANIED BY DIMINISHED HISTONE 4 ACETYLATION IN THE CYP3A2 PROMOTER (48%) AND HISTONE 3 ACETYLATION IN THE CYP2C11 (77%) AND CYP3A2 (77%) PROMOTER LOCI FOR NUCLEAR RECEPTOR ACTIVATION (P<0.05). THIS STUDY SUGGESTS THAT DECREASED NUCLEAR RECEPTOR BINDING AND HISTONE ACETYLATION MAY CONTRIBUTE TO THE MECHANISM OF DRUG-METABOLIZING ENZYME DOWN-REGULATION AND ALTERED PHARMACOKINETICS IN CKD. 2014 8 2080 38 EPIGENETIC DNA METHYLATION OF EBI3 MODULATES HUMAN INTERLEUKIN-35 FORMATION VIA NFKB SIGNALING: A PROMISING THERAPEUTIC OPTION IN ULCERATIVE COLITIS. ULCERATIVE COLITIS (UC), A SEVERE CHRONIC DISEASE WITH UNCLEAR ETIOLOGY THAT IS ASSOCIATED WITH INCREASED RISK FOR COLORECTAL CANCER, IS ACCOMPANIED BY DYSREGULATION OF CYTOKINES. EPSTEIN-BARR VIRUS-INDUCED GENE 3 (EBI3) ENCODES A SUBUNIT IN THE UNIQUE HETERODIMERIC IL-12 CYTOKINE FAMILY OF EITHER PRO- OR ANTI-INFLAMMATORY FUNCTION. AFTER HAVING RECENTLY DEMONSTRATED THAT UPREGULATION OF EBI3 BY HISTONE ACETYLATION ALLEVIATES DISEASE SYMPTOMS IN A DEXTRAN SULFATE SODIUM (DSS)-TREATED MOUSE MODEL OF CHRONIC COLITIS, WE NOW AIMED TO EXAMINE A POSSIBLE FURTHER EPIGENETIC REGULATION OF EBI3 BY DNA METHYLATION UNDER INFLAMMATORY CONDITIONS. TREATMENT WITH THE DNA METHYLTRANSFERASE INHIBITOR (DNMTI) DECITABINE (DAC) AND TNFALPHA LED TO SYNERGISTIC UPREGULATION OF EBI3 IN HUMAN COLON EPITHELIAL CELLS (HCEC). USE OF DIFFERENT SIGNALING PATHWAY INHIBITORS INDICATED NFKAPPAB SIGNALING WAS NECESSARY AND PROPORTIONAL TO THE SYNERGISTIC EBI3 INDUCTION. MALDI-TOF/MS AND HPLC-ESI-MS/MS ANALYSIS OF DAC/TNFALPHA-TREATED HCEC IDENTIFIED IL-12P35 AS THE MOST PROBABLE BINDING PARTNER TO FORM A FUNCTIONAL PROTEIN. EBI3/IL-12P35 HETERODIMERS (IL-35) INDUCE THEIR OWN GENE UPREGULATION, SOMETHING THAT WAS INDEED OBSERVED IN HCEC CULTURED WITH MEDIA FROM PREVIOUSLY DAC/TNFALPHA-TREATED HCEC. THESE RESULTS SUGGEST THAT UNDER INFLAMMATORY AND DEMETHYLATING CONDITIONS THE UPREGULATION OF EBI3 RESULTS IN THE FORMATION OF ANTI-INFLAMMATORY IL-35, WHICH MIGHT BE CONSIDERED AS A THERAPEUTIC TARGET IN COLITIS. 2021 9 197 41 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 10 5863 30 SUPPRESSION OF ALLERGIC ASTHMA BY LOSS OF FUNCTION OF MIZ1-MEDIATED TH1 SKEWING. ASTHMA IS THE MOST PREVALENT CHRONIC RESPIRATORY DISEASE WORLDWIDE. THERE IS CURRENTLY NO CURE, AND IT REMAINS AN IMPORTANT CAUSE OF MORBIDITY AND MORTALITY. HERE WE REPORT THAT LUNG-SPECIFIC LOSS OF FUNCTION OF THE TRANSCRIPTION FACTOR MIZ1 (C-MYC-INTERACTING ZINC FINGER PROTEIN-1) UPREGULATES THE PRO-T-HELPER CELL TYPE 1 CYTOKINE IL-12. UPREGULATION OF IL-12 IN TURN STIMULATES A TH1 RESPONSE, THEREBY COUNTERACTING T-HELPER CELL TYPE 2 RESPONSE AND PREVENTING THE ALLERGIC RESPONSE IN MOUSE MODELS OF HOUSE DUST MITE- AND OVA (OVALBUMIN)-INDUCED ASTHMA. USING TRANSGENIC MICE EXPRESSING CRE UNDER A CELL-SPECIFIC PROMOTER, WE DEMONSTRATE THAT MIZ1 ACTS IN LUNG EPITHELIAL CELLS AND DENDRITIC CELLS IN ASTHMA. CHROMATIN IMMUNOPRECIPITATION COUPLED WITH HIGH-THROUGHPUT DNA SEQUENCING OR QUANTITATIVE PCR REVEALS THE BINDING OF MIZ1 ON THE IL12 PROMOTER INDICATING DIRECT REPRESSION OF IL-12 BY MIZ1. IN ADDITION, HDAC1 (HISTONE DEACETYLASE 1) IS RECRUITED TO THE IL12 PROMOTER IN A MIZ1-DEPDENENT MANNER, SUGGESTING EPIGENETIC REPRESSION OF IL12 BY MIZ1. FURTHERMORE, MIZ1 IS UPREGULATED IN THE LUNGS OF ASTHMATIC MICE. OUR DATA TOGETHER SUGGEST THAT MIZ1 IS UPREGULATED DURING ASTHMA, WHICH IN TURN PROMOTES ASTHMA PATHOGENESIS BY PREVENTING TH1 SKEWING THROUGH THE TRANSCRIPTIONAL REPRESSION OF IL-12. 2022 11 6593 43 TUMOR-ASSOCIATED MACROPHAGES PROMOTE EPIGENETIC SILENCING OF GELSOLIN THROUGH DNA METHYLTRANSFERASE 1 IN GASTRIC CANCER CELLS. EPIGENETIC REPRESSION OF THE TUMOR SUPPRESSOR GELSOLIN (GSN) IS FREQUENTLY OBSERVED IN CANCERS. CHRONIC INFLAMMATION CAN PROMOTE TUMOR PROGRESSION VIA ABERRANT DNA METHYLATION. IN THIS STUDY, WE INVESTIGATED THE ROLE OF TUMOR-ASSOCIATED MACROPHAGES (TAMS) IN DNA METHYLATION OF THE GSN GENE DURING GASTRIC CANCER PROGRESSION. IMMUNOFLUORESCENCE STAINING OF 121 GASTRIC CANCER TISSUES SHOWED ABERRANT LOCALIZATION OF GSN AND DNA METHYLTRANSFERASE 1 (DNMT1) AND JUXTAPOSITION OF DNMT1 AND M2 TAMS. DECREASED GSN PROTEIN AND MRNA EXPRESSION AND INCREASED DNA METHYLATION IN THE GSN PROMOTER WERE OBSERVED IN GASTRIC CANCER CELL LINES AND CLINICAL SPECIMENS. TO EXAMINE THE EFFECT OF TAMS ON DNA METHYLATION IN GASTRIC CANCER CELLS, WE PERFORMED IN VITRO COCULTURE ASSAYS AND FOUND INCREASED DNMT1 EXPRESSION BUT DECREASED GSN EXPRESSION IN GASTRIC CANCER CELLS AFTER COCULTURE WITH U937 CELLS. KNOCKDOWN OF DNMT1 EXPRESSION IN GASTRIC CANCER CELLS COULD ABORT U937 COCULTURE-MEDIATED GSN DOWNREGULATION. MEANWHILE, CCL5 WAS THE MAIN CHEMOKINE UPREGULATED IN COCULTURE MEDIUM. TREATMENT WITH CCL5 COULD INDUCE DNMT1 EXPRESSION IN GASTRIC CANCER CELLS VIA STAT3 SIGNALING. INHIBITING DNMT1 ACTIVITY WITH PROCAINAMIDE, INHIBITING DNA METHYLATION WITH 5-AZA, OR INHIBITING CCL5/CCR5 SIGNALING WITH MARAVIROC REDUCED TUMOR GROWTH IN VIVO IN CONCLUSION, UPREGULATION OF DNMT1 BY CCL5/CCR5/STAT3 SIGNALING IS CRITICAL FOR TAM-MEDIATED GSN SILENCING IN GASTRIC CANCER. THIS STUDY IDENTIFIED POTENTIAL TARGETS FOR GASTRIC CANCER THERAPY. CANCER IMMUNOL RES; 5(10); 885-97. (C)2017 AACR. 2017 12 1622 37 DNA METHYLTRANSFERASES IN MALAR MELASMA AND THEIR MODIFICATION BY SUNSCREEN IN COMBINATION WITH 4% NIACINAMIDE, 0.05% RETINOIC ACID, OR PLACEBO. BACKGROUND: MALAR MELASMA HAS A CHRONIC AND RECURRENT CHARACTER THAT MAY BE RELATED TO EPIGENETIC CHANGES. OBJECTIVE: TO RECOGNIZE THE EXPRESSION AND DNA METHYLATION OF DNA METHYLTRANSFERASES (DNMTS) IN MALAR MELASMA AND PERILESIONAL SKIN, AS WELL AS THE CHANGES IN DNMTS AFTER THEIR TREATMENT WITH SUNSCREEN IN COMBINATION WITH 4% NIACINAMIDE, 0.05% RETINOIC ACID, OR PLACEBO. METHODS: THIRTY FEMALE PATIENTS WERE CLINICALLY EVALUATED FOR THE EXPRESSION OF DNMT1 AND DNMT3B USING REAL-TIME PCR AND IMMUNOFLUORESCENCE. THESE INITIAL RESULTS WERE COMPARED TO RESULTS AFTER EIGHT WEEKS OF TREATMENT WITH SUNSCREEN IN COMBINATION WITH NIACINAMIDE, RETINOIC ACID, OR PLACEBO. RESULTS: THE RELATIVE EXPRESSION OF DNMT1 WAS SIGNIFICANTLY ELEVATED IN MELASMA COMPARED WITH UNAFFECTED SKIN IN ALL SUBJECTS, INDICATING DNA HYPERMETHYLATION. AFTER TREATMENT, IT WAS DECREASED IN ALL GROUPS: NIACINAMIDE (7 VERSUS 1; P<0.01), RETINOIC ACID (7 VERSUS 2; P<0.05), AND PLACEBO (7 VERSUS 3; P<0.05), WHICH CORRELATES WITH CLINICAL IMPROVEMENT. DNMT3B WAS NOT OVEREXPRESSED IN LESIONAL SKIN BUT REDUCED IN ALL GROUPS. CONCLUSIONS: WE FOUND DNA HYPERMETHYLATION IN MELASMA LESIONS. ENVIRONMENTAL FACTORS SUCH AS SOLAR RADIATION MAY INDUCE CELLULAR CHANGES THAT TRIGGER HYPERPIGMENTATION THROUGH THE ACTIVATION OF PATHWAYS REGULATED BY EPIGENETIC MODIFICATIONS. HOWEVER, LIMITING OR DECREASING DNA METHYLATION THROUGH SUNSCREEN, NIACINAMIDE, AND RETINOIC ACID TREATMENTS THAT PROVIDE PHOTOPROTECTION AND GENETIC TRANSCRIPTION CAN COUNTERACT THIS. 2019 13 5601 32 RORALPHA IS CRUCIAL FOR ATTENUATED INFLAMMATORY RESPONSE TO MAINTAIN INTESTINAL HOMEOSTASIS. RETINOIC ACID-RELATED ORPHAN RECEPTOR ALPHA (RORALPHA) FUNCTIONS AS A TRANSCRIPTION FACTOR FOR VARIOUS BIOLOGICAL PROCESSES, INCLUDING CIRCADIAN RHYTHM, CANCER, AND METABOLISM. HERE, WE GENERATE INTESTINAL EPITHELIAL CELL (IEC)-SPECIFIC RORALPHA-DEFICIENT (RORALPHA(DELTAIEC)) MICE AND FIND THAT RORALPHA IS CRUCIAL FOR MAINTAINING INTESTINAL HOMEOSTASIS BY ATTENUATING NUCLEAR FACTOR KAPPAB (NF-KAPPAB) TRANSCRIPTIONAL ACTIVITY. RORALPHA(DELTAIEC) MICE EXHIBIT EXCESSIVE INTESTINAL INFLAMMATION AND HIGHLY ACTIVATED INFLAMMATORY RESPONSES IN THE DEXTRAN SULFATE SODIUM (DSS) MOUSE COLITIS MODEL. TRANSCRIPTOME ANALYSIS REVEALS THAT DELETION OF RORALPHA LEADS TO UP-REGULATION OF NF-KAPPAB TARGET GENES IN IECS. CHROMATIN IMMUNOPRECIPITATION ANALYSIS REVEALS CORECRUITMENT OF RORALPHA AND HISTONE DEACETYLASE 3 (HDAC3) ON NF-KAPPAB TARGET PROMOTERS AND SUBSEQUENT DISMISSAL OF CREB BINDING PROTEIN (CBP) AND BROMODOMAIN-CONTAINING PROTEIN 4 (BRD4) FOR TRANSCRIPTIONAL REPRESSION. TOGETHER, WE DEMONSTRATE THAT RORALPHA/HDAC3-MEDIATED ATTENUATION OF NF-KAPPAB SIGNALING CONTROLS THE BALANCE OF INFLAMMATORY RESPONSES, AND THERAPEUTIC STRATEGIES TARGETING THIS EPIGENETIC REGULATION COULD BE BENEFICIAL TO THE TREATMENT OF CHRONIC INFLAMMATORY DISEASES, INCLUDING INFLAMMATORY BOWEL DISEASE (IBD). 2019 14 1777 43 EDIBLE BLUE-GREEN ALGAE REDUCE THE PRODUCTION OF PRO-INFLAMMATORY CYTOKINES BY INHIBITING NF-KAPPAB PATHWAY IN MACROPHAGES AND SPLENOCYTES. BACKGROUND: CHRONIC INFLAMMATION CONTRIBUTES TO THE DEVELOPMENT OF PATHOLOGICAL DISORDERS INCLUDING INSULIN RESISTANCE AND ATHEROSCLEROSIS. IDENTIFICATION OF ANTI-INFLAMMATORY NATURAL PRODUCTS CAN PREVENT THE INFLAMMATORY DISEASES. METHODS: ANTI-INFLAMMATORY EFFECTS OF BLUE-GREEN ALGAE (BGA), I.E., NOSTOC COMMUNE VAR. SPHAEROIDES KUTZING (NO) AND SPIRULINA PLATENSIS (SP), WERE COMPARED IN RAW 264.7 AND MOUSE BONE MARROW-DERIVED MACROPHAGES (BMM) AS WELL AS SPLENOCYTES FROM APOLIPOPROTEIN E KNOCKOUT (APOE(-/-)) MICE FED BGA. RESULTS: WHEN MACROPHAGES PRETREATED WITH 100MUG/ML NO LIPID EXTRACT (NOE) OR SP LIPID EXTRACT (SPE) WERE ACTIVATED BY LIPOPOLYSACCHARIDE (LPS), EXPRESSION AND SECRETION OF PRO-INFLAMMATORY CYTOKINES, SUCH AS TUMOR NECROSIS FACTOR ALPHA (TNFALPHA), INTERLEUKIN 1BETA (IL-1BETA), AND IL-6, WERE SIGNIFICANTLY REPRESSED. NOE AND SPE ALSO SIGNIFICANTLY REPRESSED THE EXPRESSION OF TNFALPHA AND IL-1BETA IN BMM. LPS-INDUCED SECRETION OF IL-6 WAS LOWER IN SPLENOCYTES FROM APOE(-/-) FED AN ATHEROGENIC DIET CONTAINING 5% NO OR SP FOR 12WEEKS. IN RAW 264.7 MACROPHAGES, NOE AND SPE MARKEDLY DECREASED NUCLEAR TRANSLOCATION OF NF-KAPPAB. THE DEGREE OF REPRESSION OF PRO-INFLAMMATORY GENE EXPRESSION BY ALGAL EXTRACTS WAS MUCH STRONGER THAN THAT OF SN50, AN INHIBITOR OF NF-KAPPAB NUCLEAR TRANSLOCATION. TRICHOSTATIN A, A PAN HISTONE DEACETYLASE INHIBITOR, INCREASED BASAL EXPRESSION OF IL-1BETA AND ATTENUATED THE REPRESSION OF THE GENE EXPRESSION BY SPE. SPE SIGNIFICANTLY DOWN-REGULATED MRNA ABUNDANCE OF 11 HDAC ISOFORMS, CONSEQUENTLY INCREASING ACETYLATED HISTONE 3 LEVELS. CONCLUSION: NOE AND SPE REPRESS PRO-INFLAMMATORY CYTOKINE EXPRESSION AND SECRETION IN MACROPHAGES AND SPLENOCYTES VIA INHIBITION OF NF-KAPPAB PATHWAY. HISTONE ACETYLATION STATE IS LIKELY INVOLVED IN THE INHIBITION. GENERAL SIGNIFICANCE: THIS STUDY UNDERSCORES NATURAL PRODUCTS CAN EXERT ANTI-INFLAMMATORY EFFECTS BY EPIGENETIC MODIFICATIONS SUCH AS HISTONE ACETYLATION. 2013 15 1668 45 DOWNREGULATION OF SOCS1 INCREASES INTERFERON-INDUCED ISGYLATION DURING DIFFERENTIATION OF INDUCED-PLURIPOTENT STEM CELLS TO HEPATOCYTES. BACKGROUND & AIMS: INCREASED EXPRESSION OF IFN-STIMULATED GENE 15 (ISG15) AND SUBSEQUENTLY INCREASED ISGYLATION ARE KEY FACTORS IN THE HOST RESPONSE TO VIRAL INFECTION. IN THIS STUDY, WE SOUGHT TO CHARACTERIZE THE EXPRESSION OF ISG15, ISGYLATION, AND ASSOCIATED ENZYMES AT EACH STAGE OF DIFFERENTIATION FROM INDUCED PLURIPOTENT STEM CELLS (IPSCS) TO HEPATOCYTES. METHODS: TO STUDY THE REGULATION OF ISGYLATION, WE UTILIZED PATIENT SAMPLES AND IN VITRO CELL CULTURE MODELS INCLUDING IPSCS, HEPATOCYTES-LIKE CELLS, IMMORTALIZED CELL LINES, AND PRIMARY HUMAN HEPATOCYTES. PROTEIN/MRNA EXPRESSION WERE MEASURED FOLLOWING TREATMENT WITH POLY(I:C), IFNALPHA AND HCV INFECTION. RESULTS: WHEN COMPARED TO HLCS, WE OBSERVED SEVERAL NOVEL ASPECTS OF THE ISGYLATION PATHWAY IN IPSCS. THESE INCLUDE A LOWER BASELINE EXPRESSION OF THE ISGYLATION-ACTIVATING ENZYME, UBE1L, A LACK OF IFN-INDUCED EXPRESSION OF THE ISGYLATION-CONJUGATION ENZYME UBE2L6, AN ATTENUATED ACTIVATION OF THE TRANSCRIPTION FACTOR STAT1 AND CONSTITUTIVE EXPRESSION OF SOCS1. ISGYLATION WAS OBSERVED IN IPSCS FOLLOWING DOWNREGULATION OF SOCS1, WHICH FACILITATED STAT1 ACTIVATION AND SUBSEQUENTLY INCREASED EXPRESSION OF UBE2L6. INTRIGUINGLY, HCV PERMISSIVE TRANSFORMED HEPATOMA CELL LINES DEMONSTRATED HIGHER INTRINSIC EXPRESSION OF SOCS1 AND WEAKER ISGYLATION FOLLOWING IFN TREATMENT. SOCS1 DOWNREGULATION IN HCV-INFECTED HUH 7.5.1 CELLS LED TO INCREASED ISGYLATION. CONCLUSIONS: HEREIN, WE SHOW THAT HIGH BASAL LEVELS OF SOCS1 INHIBIT STAT1 ACTIVATION AND SUBSEQUENTLY IFN-INDUCED UBE2L6 AND ISGYLATION IN IPSCS. FURTHERMORE, AS IPSCS DIFFERENTIATE INTO HEPATOCYTES, EPIGENETIC MECHANISMS REGULATE ISGYLATION BY MODIFYING UBE1L AND SOCS1 EXPRESSION LEVELS. OVERALL, THIS STUDY DEMONSTRATES THAT THE DEVELOPMENT OF CELL-INTRINSIC INNATE IMMUNITY DURING THE DIFFERENTIATION OF IPSCS TO HEPATOCYTES PROVIDES INSIGHT INTO CELL TYPE-SPECIFIC REGULATION OF HOST DEFENSE RESPONSES AND RELATED ONCOGENIC PROCESSES. IMPACT AND IMPLICATIONS: TO ELUCIDATE THE MECHANISM UNDERLYING REGULATION OF ISGYLATION, A KEY PROCESS IN THE INNATE IMMUNE RESPONSE, WE STUDIED CHANGES IN ISGYLATION-ASSOCIATED GENES AT THE DIFFERENT STAGES OF DIFFERENTIATION FROM IPSCS TO HEPATOCYTES. WE FOUND THAT HIGH BASAL LEVELS OF SOCS1 INHIBIT STAT1 ACTIVATION AND SUBSEQUENTLY IFN-INDUCED UBE2L6 AND ISGYLATION IN IPSCS. IMPORTANTLY, EPIGENETIC REGULATION OF SOCS1 AND SUBSEQUENTLY ISGYLATION MAY BE IMPORTANT FACTORS IN THE DEVELOPMENT OF CELL TYPE-SPECIFIC HOST DEFENSE RESPONSES IN HEPATOCYTES THAT SHOULD BE CONSIDERED WHEN STUDYING CHRONIC INFECTIONS AND ONCOGENIC PROCESSES IN THE LIVER. 2022 16 6243 41 THE MECHANISM OF APOLIPROTEIN A1 DOWN-REGULATED BY HEPATITIS B VIRUS. BACKGROUND: HEPATITIS B VIRUS (HBV) INFECTION CORRELATED WITH THE DEVELOPMENT OF CIRRHOSIS, LIVER FAILURE AND HEPATOCELLULAR CARCINOMA (HCC), POSES A HUGE HEALTH BURDEN ON THE GLOBAL COMMUNITY. HOWEVER, THE PATHOGENESIS OF CHRONIC HEPATITIS B (CHB) REMAINS UNCLEAR. APOLIPOPROTEIN A1 (APOA1) MAINLY SECRETED BY HEPATOCYTES, REPRESENTS THE MAJOR PROTEIN COMPONENT OF HIGH-DENSITY LIPOPROTEIN. APOA1 SECRETION MAY BE DISRUPTED BY HBV INFECTION. IN THIS STUDY, WE MAINLY INVESTIGATED THE MOLECULAR MECHANISM OF APOA1 DOWN REGULATED BY HBV FOR REVEALING THE PATHOGENESIS OF CHB. METHODS: APOA1 EXPRESSION IN LIVERS OF CHB PATIENTS AS WELL AS HEALTHY CONTROLS WERE PERFORMED BY REAL-TIME PCR (RT-PCR) AND WESTERN BLOT. THE SERUM APOA1 LEVELS WERE MEASURED BY ENZYMED-LINKED IMMUNOSORBENT ASSAY (ELISA). EXPRESSION OF APOA1 MRNA AND PROTEIN LEVELS WERE PERFORMED BY RT-PCR AND WESTERN BLOT IN HUMAN HEPATOMA HEPG2 CELLS AND SUBLINE HEPG2.2.15 CELLS. HBV EXPRESSION CONSTRUCT, PHBV1.3 WERE TRANSFECTED INTO HEPG2, THE CHANGES OF APOA1 MRNA AND PROTEIN EXPRESSION WERE DETECTED BY RT-PCR AND WESTERN BLOT. TO FURTHER STUDY THE MECHANISM OF APOA1 DOWN REGULATION BY HBV, 11 CPG ISLANDS IN APOA1 PROMOTOR WERE TESTED FOR DNA METHYLATION STATUS BY MSP. HEPG2.2.15 CELL LINES WERE TREATED WITH DNA METHYLTRANSFERASE INHIBITOR 5-AZA-DEOXYCYTIDINE (5-AZA-DC), THEN, EXPRESSION OF APOA1 MRNA AND HBV PARTICLES IN THE SUPERNATANT, AS WELL AS APOA1 PROTEIN LEVELS WERE DETECTED BY RT-PCR AND WESTERN BLOT. SECRETION OF HBSAG AND HBEAG IN HEPG2 CELLS COTRANSFECTED WITH PAPOA1 AND PHBV1.3 CONSTRUCTS WAS TESTED BY ELISA. MEANWHILE, SECRETION OF HBSAG AND HBEAG IN THE SUPERNATANT WERE QUANTIFIED BY ELISA IN THE HEPG2.2.15 CELLS TREATED WITH 5-AZA-DC PLUS APOA1 SIRNA. RESULTS: EXPRESSION OF APOA1 MRNA AND PROTEIN LEVELS, AS WELL AS SERUM APOA1 LEVELS IN CHB PATIENTS WERE DECREASED CORRESPONDING HEALTHY CONTROLS IN VIVO. IN ADDITION, THE EXPRESSION OF APOA1 MRNA AND PROTEIN LEVELS WERE DOWN REGULATED IN HEPG2.2.15 CELLS CORREPONDING HEPG2 CELLS, 11 CPG ISLANDS IN APOA1 PROMOTER WERE TESTED FOR METHYLATION STATUS BY MSP IN HEPG2.2.15 CELLS COMPARED TO HEPG2 CELLS, WHILE TWO CPG ISLANDS WERE FOUND HYPERMETHYLATED. EXPRESSION OF APOA1 MRNA AND PROTEIN LEVELS WERE INCREASED IN HEPG2.2.15 CELLS TREATED WITH DNA METHYLTRANSFERASE INHIBITOR 5-AZA-DC. FURTHERMORE, OVEREXPRESSION OF APOA1 CAN ENHANCE HBV EXPRESSION IN HEPG2 CELLS WHILE THE INHIBITORY EFFECT OF 5-AZA-DC ON HBV EXPRESSION WAS COMPLETELY ABOLISHED BY BLOCKING 5-AZA-DC-INDUCED UP-REGULATION OF APOA1 USING RNAI. CONCLUSIONS: EPIGENETIC SILENCING OF APOA1 GENE EXPRESSION BY CPG ISLAND DNA HYPERMETHYLATION INDUCED BY HBV MAY CONTRIBUTE TO THE PATHOGENESIS OF CHB. 2016 17 368 38 AMYLOID BETA-MEDIATED EPIGENETIC ALTERATION OF INSULIN-LIKE GROWTH FACTOR BINDING PROTEIN 3 CONTROLS CELL SURVIVAL IN ALZHEIMER'S DISEASE. SWEDISH DOUBLE MUTATION (KM670/671NL) OF AMYLOID PRECURSOR PROTEIN (APP) IS REPORTED TO INCREASE TOXIC AMYLOID BETA (ABETA) PRODUCTION VIA ABERRANT CLEAVAGE AT THE BETA-SECRETASE SITE AND THEREBY CAUSE EARLY-ONSET ALZHEIMER'S DISEASE (AD). HOWEVER, THE UNDERLYING MOLECULAR MECHANISMS LEADING TO AD PATHOGENESIS REMAINS LARGELY UNKNOWN. PREVIOUSLY, OUR TRANSCRIPTOME SEQUENCE ANALYSES REVEALED GLOBAL EXPRESSIONAL MODIFICATIONS OF OVER 600 GENES IN APP-SWEDISH MUTANT-EXPRESSING H4 (H4-SW) CELLS COMPARED TO WILD TYPE H4 CELLS. INSULIN-LIKE GROWTH FACTOR BINDING PROTEIN 3 (IGFBP3) IS ONE GENE THAT SHOWED SIGNIFICANTLY DECREASED MRNA EXPRESSION IN H4-SW CELLS. IN THIS STUDY, WE INVESTIGATED THE FUNCTIONAL ROLE OF IGFBP3 IN AD PATHOGENESIS AND ELUCIDATED THE MECHANISMS REGULATING ITS EXPRESSION. WE OBSERVED DECREASED IGFBP3 EXPRESSION IN THE H4-SW CELL LINE AS WELL AS THE HIPPOCAMPUS OF AD MODEL TRANSGENIC MICE. TREATMENT WITH EXOGENOUS IGFBP3 PROTEIN INHIBITED ABETA1-42- INDUCED CELL DEATH AND CASPASE-3 ACTIVITY, WHEREAS SIRNA-MEDIATED SUPPRESSION OF IGFBP3 EXPRESSION INDUCED CELL DEATH AND CASPASE-3 CLEAVAGE. IN PRIMARY HIPPOCAMPAL NEURONS, ADMINISTRATION OF IGFBP3 PROTEIN BLOCKED APOPTOTIC CELL DEATH DUE TO ABETA1-42 TOXICITY. THESE DATA IMPLICATE A PROTECTIVE ROLE FOR IGFBP3 AGAINST ABETA1-42-MEDIATED APOPTOSIS. NEXT, WE INVESTIGATED THE REGULATORY MECHANISMS OF IGFBP3 EXPRESSION IN AD PATHOGENESIS. WE OBSERVED ABNORMAL IGFBP3 HYPERMETHYLATION WITHIN THE PROMOTER CPG ISLAND IN H4-SW CELLS. TREATMENT WITH THE DNA METHYLTRANSFERASE INHIBITOR 5-AZA-2'-DEOXYCYTIDINE RESTORED IGFBP3 EXPRESSION AT BOTH THE MRNA AND PROTEIN LEVELS. CHRONIC EXPOSURE TO ABETA1-42 INDUCED IGFBP3 HYPERMETHYLATION AT CPGS, PARTICULARLY AT LOCI -164 AND -173, AND SUBSEQUENTLY SUPPRESSED IGFBP3 EXPRESSION. THEREFORE, WE DEMONSTRATE THAT EXPRESSION OF ANTI-APOPTOTIC IGFBP3 IS REGULATED BY EPIGENETIC DNA METHYLATION, SUGGESTING A MECHANISM THAT CONTRIBUTES TO AD PATHOGENESIS. 2014 18 2763 37 EXPRESSION OF THE LEUKEMIC PROGNOSTIC MARKER CD7 IS LINKED TO EPIGENETIC MODIFICATIONS IN CHRONIC MYELOID LEUKEMIA. BACKGROUND: EXPRESSION LEVELS OF THE CELL SURFACE GLYCOPROTEIN, CD7, AND THE SERINE PROTEASE, ELASTASE 2 (ELA2), IN THE LEUKEMIC CELLS OF PATIENTS WITH CHRONIC MYELOID LEUKEMIA (CML) HAVE BEEN ASSOCIATED WITH CLINICAL OUTCOME. HOWEVER, LITTLE IS KNOWN ABOUT THE MECHANISMS THAT UNDERLIE THE VARIABLE EXPRESSION OF THESE GENES IN THE LEUKEMIC CELLS. RESULTS: TO ADDRESS THIS QUESTION, WE COMPARED THE LEVEL OF THEIR EXPRESSION WITH THE DNA METHYLATION AND HISTONE ACETYLATION STATUS OF 5' SEQUENCES OF BOTH GENES IN LEUKEMIC CELL LINES AND PRIMITIVE (LIN-CD34+) LEUKEMIC CELLS FROM CHRONIC PHASE CML PATIENTS. DNA METHYLATION OF THE ELA2 GENE PROMOTER DID NOT CORRELATE WITH ITS EXPRESSION PATTERN IN LIN-CD34+ CELLS FROM CHRONIC PHASE CML PATIENT SAMPLES EVEN THOUGH THERE WAS CLEAR DIFFERENTIAL DNA METHYLATION OF THIS LOCUS IN ELA2-EXPRESSING AND NON-EXPRESSING CELL LINES. IN CONTRAST, WE FOUND A STRONG RELATION BETWEEN CD7 EXPRESSION AND TRANSCRIPTION-PERMISSIVE CHROMATIN MODIFICATIONS, BOTH AT THE LEVEL OF DNA METHYLATION AND HISTONE ACETYLATION WITH EVIDENCE OF HYPOMETHYLATION OF THE CD7 PROMOTER REGION IN THE LIN-CD34+ CELLS FROM CML PATIENTS WITH HIGH CD7 EXPRESSION. CONCLUSION: THESE FINDINGS INDICATE A LINK BETWEEN EPIGENETIC MODIFICATIONS AND CD7 EXPRESSION IN PRIMITIVE CML CELLS. 2010 19 2432 44 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 20 3161 38 GRAINYHEAD-LIKE 2 (GRHL2) INHIBITS KERATINOCYTE DIFFERENTIATION THROUGH EPIGENETIC MECHANISM. WE RECENTLY IDENTIFIED GRAINYHEAD-LIKE 2 (GRHL2), A MAMMALIAN HOMOLOG OF GRAINYHEAD IN DROSOPHILA, TO BE A NOVEL TRANSCRIPTION FACTOR THAT REGULATES HTERT GENE EXPRESSION AND ENHANCES PROLIFERATION OF NORMAL HUMAN EPIDERMAL KERATINOCYTES (NHEK). IN THE CURRENT STUDY, WE SHOW THAT GRHL2 IMPAIRS KERATINOCYTE DIFFERENTIATION THROUGH TRANSCRIPTIONAL INHIBITION OF THE GENES CLUSTERED AT THE EPIDERMAL DIFFERENTIATION COMPLEX (EDC), LOCATED AT CHROMOSOME 1Q21. GENE EXPRESSION PROFILING AND SUBSEQUENT IN VITRO ASSAYS REVEALED CONSISTENT DOWNREGULATION OF EDC GENES, FOR EXAMPLE, IVL, KRT1, FLG, LCES, AND SPRRS, IN NHEK EXPRESSING EXOGENOUS GRHL2. IN VIVO BINDING ASSAY BY CHROMATIN IMMUNOPRECIPITATION REVEALED GRHL2 ASSOCIATION AT THE PROMOTER REGIONS OF ITS TARGET GENES, MANY OF WHICH BELONG TO EDC. EXOGENOUS GRHL2 EXPRESSION ALSO INHIBITED RECRUITMENT OF HISTONE DEMETHYLASE JMJD3 TO THE EDC GENE PROMOTERS AND ENHANCED THE LEVEL OF HISTONE 3 LYS 27 TRIMETHYLATION ENRICHMENT AT THESE PROMOTERS. SURVEY OF GRHL2 EXPRESSION IN HUMAN SKIN TISSUES DEMONSTRATED ENHANCED PROTEIN AND MRNA LEVELS IN CHRONIC SKIN LESIONS WITH IMPAIRED KERATINOCYTE DIFFERENTIATION, FOR EXAMPLE, ATOPIC DERMATITIS AND PSORIASIS, COMPARED WITH NORMAL EPIDERMIS. THESE DATA INDICATE THAT GRHL2 IMPAIRS EPIDERMAL DIFFERENTIATION BY INHIBITING EDC GENE EXPRESSION THROUGH EPIGENETIC MECHANISMS AND SUPPORT ITS ROLE IN THE HYPERPROLIFERATIVE SKIN DISEASES. 2012