1 1338 160 DESIGN, SYNTHESIS AND BIOLOGICAL EVALUATION OF A PHENYL BUTYRIC ACID DERIVATIVE, N-(4-CHLOROPHENYL)-4-PHENYLBUTANAMIDE: A HDAC6 INHIBITOR WITH ANTI-PROLIFERATIVE ACTIVITY ON CERVIX CANCER AND LEUKEMIA CELLS. BACKGROUND: THE EPIGENETIC REGULATION OF GENES IN CANCER COULD BE TARGETED BY INHIBITING HISTONE DEACETYLASE 6 (HDAC6), AN ENZYME INVOLVED IN SEVERAL TYPES OF CANCER SUCH AS LYMPHOMA, LEUKEMIA, OVARIAN CANCER, ETC. OBJECTIVE: THROUGH IN SILICO METHODS, A SET OF PHENYL BUTYRIC ACID DERIVATIVES WITH POSSIBLE HDAC6 INHIBITORY ACTIVITY WERE DESIGNED, RENDERING MONOPHENYLAMIDES AND BIPHENYLAMIDES USING TUBACIN (HDAC6 SELECTIVE INHIBITOR) AS REFERENCE. METHOD: THE TARGET COMPOUNDS WERE SUBMITTED TO THEORETICAL ADMET ANALYSES AND THEIR BINDING PROPERTIES ON DIFFERENT HDAC6 CONFORMERS WERE EVALUATED THROUGH DOCKING CALCULATIONS. RESULTS: THESE IN SILICO STUDIES ALLOWED US TO IDENTIFY A COMPOUND NAMED B-R2B. IN ORDER TO HAVE MORE INFORMATION ABOUT THE B-R2B BINDING RECOGNITION PROPERTIES ON HDAC6, THE B-R2B-HDAC6 COMPLEX WAS SUBMITTED THROUGH 100 NS-LONG MOLECULAR DYNAMICS (MD) SIMULATION COUPLED TO MMGBSA APPROACH, REVEALING THAT B-R2B IS LOCATED AT THE ENTRANCE OF HDAC6 ACTIVE POCKET, BLOCKING THE PASSAGE OF THE SUBSTRATE WITHOUT REACHING THE HDAC6 BINDING SITE. BASED ON THESE RESULTS, B-R2B WAS SYNTHESIZED, CHARACTERIZED AND BIOLOGICALLY TESTED. THE HDAC6 FLUOROMETRIC DRUG DISCOVERY KIT FLUOR-DE-LYS (ENZO LIFE SCIENCES INC.) WAS USED TO DETERMINE THE HDAC6 HUMAN INHIBITORY ACTIVITY (IC50 VALUE) OF B-R2B COMPOUND. IN ADDITION, B-R2B SHOW IC50 VALUES ON CANCER CELL LINES (HELA; IC50 = 72.6 MICROM), ACUTE MYELOID LEUKEMIA (THP-1; IC50 = 16.5 MICROM), HUMAN MAST LEUKEMIA (HMC; IC50 = 79.29 MICROM) AND CHRONIC MYELOGENOUS LEUKEMIA (KASUMI; IC50 = 101 MICROM). CONCLUSION: THESE RESULTS SHOW THAT B-R2B IS A HDAC6 INHIBITOR, SPECIFICALLY A NON-COMPETITIVE TYPE IN A SIMILAR WAY THAT TUBACIN DOES, ACCORDING TO MD SIMULATIONS. 2017 2 1358 31 DEVELOPMENT OF RATIOMETRIC ELECTROCHEMICAL MOLECULAR SWITCHES TO ASSAY ENDOGENOUS FORMALDEHYDE IN LIVE CELLS, WHOLE BLOOD AND CREATININE IN SALIVA. FORMALDEHYDE IS A REACTIVE CARBONYL SPECIES (RCS) THAT IS PRODUCED NATURALLY IN THE HUMAN BODY VIA METABOLIC AND EPIGENETIC BIOCHEMICAL PROCESSES, YET IN HIGH CONCENTRATIONS IS HIGHLY TOXIC TO THE ENVIRONMENT AS WELL AS TO LIVING ORGANISMS. THEREFORE, WE DESIGNED TWO RATIOMETRIC ELECTROCHEMICAL MOLECULAR REDOX PROBES, FORMALDEHYDE OXIDATIVE LATENT PROBE (FOLP) AND DIHYDROXY-FORMALDEHYDE OXIDATIVE LATENT PROBE (HFOLP), FOR THE SELECTIVE PROFILING OF ENDOGENOUS FORMALDEHYDE. FOLP AND HFOLP EACH UNDERWENT THE AZA-COPE REACTION WITH FORMALDEHYDE FOLLOWED BY HYDROLYSIS TO ELIMINATE UNMASK REDOX REPORTER N-ALKYLATED AMINOFERROCENE (AAF) TO MONITOR THEIR RESPONSE CURRENT. THE FOLP AND HFOLP SENSORS SHOWED BROAD DYNAMIC RANGES OF 0.12-1000 MUM AND 0.09-3 MM FOR FORMALDEHYDE WITH DETECTION LIMITS OF 48.2 NM AND 31.6 MUM, RESPECTIVELY. ALSO, SINCE FORMALDEHYDE IS THE BYPRODUCT OF BIOCHEMICAL REACTIONS FOR DETECTING CREATININE AND CREATININE IS AN IMPORTANT BIOMARKER FOR CHRONIC KIDNEY DISEASE (CKD), WE TESTED THE FOLP PROBE FOR ITS ABILITY TO MONITOR CREATININE. IT SUCCESSFULLY DID SO, AND THIS ABILITY WAS USED TO DEVELOP AN ELECTROCHEMICAL PLATFORM FOR THE QUANTIFICATION OF CREATININE; IT SHOWED A DYNAMIC RANGE OF 3.25-200 MUM AND A LIMIT OF DETECTION (1.3 MUM). IN ADDITION, THE FOLP-BASED ASSAY PLATFORM DELIVERED A RELIABLE ANALYTICAL PERFORMANCE FOR THE QUANTIFICATION OF FORMALDEHYDE IN HUMAN WHOLE BLOOD AND OF CREATININE IN SALIVA, AND ALSO FOR THE REAL-TIME MONITORING OF ENDOGENOUS FORMALDEHYDE SECRETION IN HELA CELLS. MOREOVER, THE CONCENTRATIONS DETERMINED USING OUR METHOD WERE FOUND TO BE CONSISTENT WITH THOSE DETERMINED USING FORMALDEHYDE AND CREATININE FLUOROMETRIC ASSAY KITS. 2021 3 4267 25 MICROARRAY DATASET OF TRANSIENT AND PERMANENT DNA METHYLATION CHANGES IN HELA CELLS UNDERGOING INORGANIC ARSENIC-MEDIATED EPITHELIAL-TO-MESENCHYMAL TRANSITION. THE NOVEL DATASET PRESENTED HERE REPRESENTS THE RESULTS OF THE CHANGING PATTERN OF DNA METHYLATION PROFILES IN HELA CELLS EXPOSED TO CHRONIC LOW DOSE (0.5 MICROM) SODIUM ARSENITE, RESULTING IN EPITHELIAL-TO-MESENCHYMAL TRANSITION, AS WELL AS DNA METHYLATION PATTERNS IN CELLS WHERE INORGANIC ARSENIC HAS BEEN REMOVED. INORGANIC ARSENIC IS A KNOWN CARCINOGEN, THOUGH NOT MUTAGENIC. SEVERAL MECHANISMS HAVE BEEN PROPOSED AS TO HOW INORGANIC ARSENIC DRIVES CARCINOGENESIS SUCH AS REGULATION OF THE CELL?S REDOX POTENTIAL AND/OR EPIGENETICS. IN FACT, THERE ARE GENE SPECIFIC STUDIES AND LIMITED GENOME-WIDE STUDIES THAT HAVE IMPLICATED EPIGENETIC FACTORS SUCH AS DNA METHYLATION IN INORGANIC ARSENIC-MEDIATED EPITHELIAL-TO-MESENCHYMAL TRANSITION (EMT). HOWEVER, GENOME-WIDE STUDIES ABOUT THE IMPACT OF 1) CHRONIC, LOW-DOSE INORGANIC ARSENIC EXPOSURE ON DNA METHYLATION PATTERNS DURING INORGANIC ARSENIC-INDUCED EPITHELIAL-TO-MESENCHYMAL TRANSITION, AND 2) THE REMOVAL INORGANIC ARSENIC (REVERSAL) ON DNA METHYLATION PATTERNS, IS LACKING. FOR THIS DATASET, TWO REPLICATES WERE PERFORMED WITH EACH OF THE SAMPLES - NON-TREATED, INORGANIC ARSENIC-TREATED, AND REVERSE-TREATED CELLS. WE PROVIDE NORMALIZED AND PROCESSED DATA, AND LOG2 FOLD CHANGE IN DNA METHYLATION. THE RAW MICROARRAY DATA ARE AVAILABLE THROUGH NCBI GEO, ACCESSION NUMBER GSE95232 AND A RELATED RESEARCH PAPER HAS BEEN ACCEPTED FOR PUBLISHED IN TOXICOLOGY AND APPLIED PHARMACOLOGY (ECKSTEIN ET AL., 2017) [1]. 2017 4 908 26 CHRONIC EXPOSURE TO ENVIRONMENTALLY RELEVANT CONCENTRATION OF FLUORIDE IMPAIRS OSTEOBLAST'S COLLAGEN SYNTHESIS AND MATRIX MINERALIZATION: INVOLVEMENT OF EPIGENETIC REGULATION IN SKELETAL FLUOROSIS. GLOBALLY, 200 MILLION PEOPLE ARE SUFFERING FROM TOXIC MANIFESTATIONS OF FLUORIDE(F), DENTAL AND SKELETAL FLUOROSIS; UNFORTUNATELY, THERE IS NO TREATMENT. TO UNRAVEL THE PATHOGENESIS OF SKELETAL FLUOROSIS, WE ESTABLISHED FLUOROSIS MICE BY TREATING ENVIRONMENTALLY RELEVANT CONCENTRATION OF F (15 PPM NAF) THROUGH DRINKING WATER FOR 4 MONTHS. AS IN SKELETAL FLUOROSIS, LOCOMOTOR DISABILITY, CRIPPLING DEFORMITIES OCCUR AND THUS, OUR HYPOTHESIS WAS F MIGHT ADVERSELY AFFECTS COLLAGEN WHICH GIVES THE BONE TENSILE STRENGTH. THIS WORK INEVITABLY HAD TO BE CARRIED OUT ON OSTEOBLAST CELLS, RESPONSIBLE FOR SYNTHESIS, DEPOSITION, AND MINERALIZATION OF BONE MATRIX. ISOLATED OSTEOBLAST CELLS WERE CONFIRMED BY ALP ACTIVITY AND MINERALIZED NODULES FORMATION. EXPRESSION OF COLLAGEN COL1A1, COL1A2, COL1A1 WAS SIGNIFICANTLY REDUCED IN TREATED MICE. FURTHER, A STUDY REVEALED THE INVOLVEMENT OF EPIGENETIC REGULATION BY PROMOTER HYPERMETHYLATION OF COL1A1; EXPRESSIONAL ALTERATIONS OF TRANSCRIPTION FACTORS, CALCIUM CHANNELS AND OTHER GENES E.G., CBFA-1, TGF-BETA1, BMP1, SP1, SP7, NF-(K)B P65, BMP-2, BGLAP, GPRC6A AND CAV(1.2) ARE ASSOCIATED WITH IMPAIRMENT OF COLLAGEN SYNTHESIS, DEPOSITION AND DECREASED MINERALIZATION THUS, ENFEEBLING BONE HEALTH. THIS STUDY INDICATES THE POSSIBLE ASSOCIATION OF EPIGENETIC REGULATION IN SKELETAL FLUOROSIS. HOWEVER, NO ASSOCIATION WAS FOUND BETWEEN POLYMORPHISMS IN THE COL1A1 (RSAI, HINDIII) AND COL1A2 (RSAI, HINDIII) GENES WITH FLUOROSIS IN MICE. 2023 5 5556 27 ROLE OF FLUORIDE INDUCED HISTONE TRIMETHYLATION IN DEVELOPMENT OF SKELETAL FLUOROSIS. CHRONIC EXPOSURE TO FLUORIDE HAS BEEN ASSOCIATED WITH THE DEVELOPMENT OF SKELETAL FLUOROSIS. LIMITED REPORTS ARE AVAILABLE ON FLUORIDE INDUCED HISTONE MODIFICATION. HOWEVER, THE ROLE OF HISTONE MODIFICATION IN THE PATHOGENESIS OF SKELETAL FLUOROSIS IS NOT INVESTIGATED. IN THE PRESENT STUDY, WE HAVE INVESTIGATED THE ROLE OF FLUORIDE INDUCED HISTONE MODIFICATION ON FLUOROSIS DEVELOPMENT USING HUMAN OSTEOSARCOMA (HOS) CELL LINE. THE EXPRESSION OF HISTONE METHYLTRANSFERASES (EHMT1 AND EHZ2) AND LEVEL OF GLOBAL HISTONE TRIMETHYLATION (H3K9 AND H3K27) HAVE BEEN ASSESSED AND OBSERVED TO BE INCREASED SIGNIFICANTLY AFTER FLUORIDE EXPOSURE (8 MG/L). EPITECT CHROMATIN IMMUNOPRECIPITATION (CHIP) QPCR ARRAY (HUMAN TGFBETA/BMP SIGNALING PATHWAY) WAS PERFORMED TO ASSESS THE H3K9 TRIMETHYLATION AT PROMOTER REGIONS OF PATHWAY-SPECIFIC GENES. H3K9 CHIP PCR ARRAY ANALYSIS IDENTIFIED HYPER H3K9 TRIMETHYLATION IN PROMOTER REGIONS OF TGFBR2 AND SMAD3. QPCR AND STRING ANALYSIS WAS CARRIED OUT TO DETERMINE THE REPRESSIVE EPIGENETIC EFFECT OF H3K9 TRIMETHYLATION ON EXPRESSION PATTERN AND FUNCTIONAL ASSOCIATION OF IDENTIFIED GENES. IDENTIFIED GENES (TGFBR2 AND SMAD3) SHOWED DOWN-REGULATION WHICH CONFIRMS THE REPRESSIVE EPIGENETIC EFFECT OF PROMOTER H3K9 HYPER TRIMETHYLATION. EXPRESSION OF TWO OTHER VITAL GENES COL1A1 AND MMP13 INVOLVED IN TGFBR2-SMAD SIGNALING PATHWAY WAS ALSO FOUND TO BE DOWN-REGULATED WITH A DECREASE IN EXPRESSION OF TGFBR2 AND SMAD3. STRING ANALYSIS REVEALED FUNCTIONAL ASSOCIATION AND INVOLVEMENT OF IDENTIFIED GENES TGFBR2, SMAD3, COL1A1 AND MMP13 IN THE COLLAGEN AND CARTILAGE DEVELOPMENT/MORPHOGENESIS, CONNECTIVE TISSUE FORMATION, BIO-MINERAL TISSUE DEVELOPMENT, ENDOCHONDRAL BONE FORMATION, BONE AND SKELETAL MORPHOGENESIS. IN CONCLUSION, PRESENT INVESTIGATION IS A FIRST ATTEMPT TO LINK FLUORIDE INDUCED HYPER H3K9 TRI-METHYLATION MEDIATED REPRESSION OF TGFBR2 AND SMAD3 WITH THE DEVELOPMENT OF SKELETAL FLUOROSIS. 2018 6 6586 32 TUBASTATIN, A SELECTIVE HISTONE DEACETYLASE 6 INHIBITOR SHOWS ANTI-INFLAMMATORY AND ANTI-RHEUMATIC EFFECTS. EPIGENETIC MODIFICATIONS REPRESENT A PROMISING NEW APPROACH TO MODULATE CELL FUNCTIONS AS OBSERVED IN AUTOIMMUNE DISEASES. EMERGING EVIDENCE SUGGESTS THE UTILITY OF HDAC INHIBITORS IN THE TREATMENT OF CHRONIC IMMUNE AND INFLAMMATORY DISORDERS. HOWEVER, CLASS AND ISOFORM SELECTIVE INHIBITION OF HDAC IS CURRENTLY FAVORED AS IT LIMITS THE TOXICITY THAT HAS BEEN OBSERVED WITH PAN-HDAC INHIBITORS. HDAC6, A MEMBER OF THE HDAC FAMILY, WHOSE MAJOR SUBSTRATE IS ALPHA-TUBULIN, IS BEING INCREASINGLY IMPLICATED IN THE PATHOGENESIS OF INFLAMMATORY DISORDERS. THE PRESENT STUDY WAS CARRIED OUT TO STUDY THE POTENTIAL ANTI-INFLAMMATORY AND ANTI-RHEUMATIC EFFECTS OF HDAC6 SELECTIVE INHIBITOR TUBASTATIN. TUBASTATIN, A POTENT HUMAN HDAC6 INHIBITOR WITH AN IC50 OF 11 NM SHOWED SIGNIFICANT INHIBITION OF TNF-ALPHA AND IL-6 IN LPS STIMULATED HUMAN THP-1 MACROPHAGES WITH AN IC50 OF 272 NM AND 712 NM RESPECTIVELY. ADDITIONALLY, TUBASTATIN INHIBITED NITRIC OXIDE (NO) SECRETION IN MURINE RAW 264.7 MACROPHAGES DOSE DEPENDENTLY WITH AN IC50 OF 4.2 MUM AND INDUCED ALPHA-TUBULIN HYPERACETYLATION CORRESPONDING TO HDAC6 INHIBITION IN THP-1 CELLS WITHOUT AFFECTING THE CELL VIABILITY. TUBASTATIN SHOWED SIGNIFICANT INHIBITION OF PAW VOLUME AT 30 MG/KG I.P. IN A FREUND'S COMPLETE ADJUVANT (FCA) INDUCED ANIMAL MODEL OF INFLAMMATION. THE DISEASE MODIFYING ACTIVITY OF TUBASTATIN WAS ALSO EVIDENT IN COLLAGEN INDUCED ARTHRITIS DBA1 MOUSE MODEL AT 30 MG/KG I.P. THE SIGNIFICANT ATTENUATION OF CLINICAL SCORES (~70%) BY TUBASTATIN WAS CONFIRMED HISTOPATHOLOGICALLY AND WAS FOUND COMPARABLE TO DEXAMETHASONE (~90% INHIBITION OF CLINICAL SCORES). TUBASTATIN SHOWED SIGNIFICANT INHIBITION OF IL-6 IN PAW TISSUES OF ARTHRITIC MICE. THE PRESENT WORK HAS DEMONSTRATED ANTI-INFLAMMATORY AND ANTIRHEUMATIC EFFECTS OF A SELECTIVE HDAC6 INHIBITOR TUBASTATIN. 2013 7 2838 29 FORMALDEHYDE CARCINOGENICITY RESEARCH: 30 YEARS AND COUNTING FOR MODE OF ACTION, EPIDEMIOLOGY, AND CANCER RISK ASSESSMENT. FORMALDEHYDE IS A WIDELY USED HIGH PRODUCTION CHEMICAL THAT IS ALSO RELEASED AS A BYPRODUCT OF COMBUSTION, OFF-GASSING OF VARIOUS BUILDING PRODUCTS, AND AS A FIXATIVE FOR PATHOLOGISTS AND EMBALMERS. WHAT IS NOT OFTEN REALIZED IS THAT FORMALDEHYDE IS ALSO PRODUCED AS A NORMAL PHYSIOLOGIC CHEMICAL IN ALL LIVING CELLS. IN 1980, CHRONIC INHALATION OF HIGH CONCENTRATIONS OF FORMALDEHYDE WAS SHOWN TO BE CARCINOGENIC, INDUCING A HIGH INCIDENCE OF NASAL SQUAMOUS CELL CARCINOMAS IN RATS. SOME EPIDEMIOLOGIC STUDIES HAVE ALSO FOUND INCREASED NUMBERS OF NASOPHARYNGEAL CARCINOMA AND LEUKEMIA IN HUMANS EXPOSED TO FORMALDEHYDE THAT RESULTED IN FORMALDEHYDE BEING CONSIDERED A KNOWN HUMAN CARCINOGEN. THIS ARTICLE REVIEWS THE DATA FOR RODENT AND HUMAN CARCINOGENICITY, EARLY MODE OF ACTION STUDIES, MORE RECENT MOLECULAR STUDIES OF BOTH ENDOGENOUS AND EXOGENOUS DNA ADDUCTS, AND EPIGENETIC STUDIES. IT GOES ON TO DEMONSTRATE THE POWER OF THESE RESEARCH STUDIES TO PROVIDE CRITICAL DATA TO IMPROVE OUR ABILITY TO DEVELOP SCIENCE-BASED CANCER RISK ASSESSMENTS, INSTEAD OF DEFAULT APPROACHES. THE COMPLEXITY OF CONSTANT PHYSIOLOGIC EXPOSURE TO A KNOWN CARCINOGEN REQUIRES THAT NEW WAYS OF THINKING BE INCORPORATED INTO DETERMINATIONS OF CANCER RISK ASSESSMENT FOR FORMALDEHYDE, OTHER ENDOGENOUS CARCINOGENS, AND THE ROLE OF BACKGROUND ENDOGENOUS DNA DAMAGE AND MUTAGENESIS. 2013 8 4341 31 MIGRATION TEST OF BISPHENOL A FROM POLYCARBONATE CUPS USING EXCITATION-EMISSION FLUORESCENCE DATA WITH PARALLEL FACTOR ANALYSIS. BISPHENOL A (BPA) IS ONE OF THE MOST LARGELY PRODUCED CHEMICAL IN THE WORLD; IT IS USED TO MAKE PLASTICS AND EPOXY RESINS. THE ENDOCRINE DISRUPTOR POTENTIAL OF BPA IS WELL KNOWN, BUT RECENT RESEARCHES SUGGEST A RELATIONSHIP BETWEEN CHRONIC EXPOSURE TO BPA, GENOTOXIC ACTIVITY AND EPIGENETIC MODIFICATIONS. THE MAIN SOURCE OF EXPOSURE TO BPA INCLUDES FOOD CONTACT MATERIALS (FCM). THUS SIMPLE AND ROBUST TEST METHODS ARE NEEDED TO IMPROVE THE MIGRATION TEST OF BPA. IN THIS WORK, A NON-SEPARATIVE, EASY, FAST AND INEXPENSIVE SPECTROFLUORIMETRIC METHOD BASED ON THE SECOND ORDER CALIBRATION OF EXCITATION-EMISSION FLUORESCENCE MATRICES (EEMS) WAS PROPOSED FOR THE DETERMINATION OF BPA. FOR THE FIRST TIME, MOLECULAR FLUORESCENCE WAS USED TO IDENTIFY UNEQUIVOCALLY AND QUANTIFY BPA. TRILINEARITY OF THE DATA TENSOR GUARANTEES THE UNIQUENESS OF THE SOLUTION OBTAINED THROUGH PARALLEL FACTOR ANALYSIS (PARAFAC), SO ONE FACTOR OF THE DECOMPOSITION MATCHES UP WITH BPA EVEN IF OTHER FLUOROPHORES ARE IN THE TEST SAMPLE. THE EFFECT OF FOUR EXPERIMENTAL FACTORS OF THE PROCEDURE ON THE FIGURES OF MERIT AND THE UNEQUIVOCALLY IDENTIFICATION WAS INVESTIGATED BY MEANS OF A D-OPTIMAL DESIGN AND PARAFAC CALIBRATION. THE METHOD IS LINEAR AND ACCURATE IN THE RANGE 0-720MICROGL(-1). THE DECISION LIMIT CCALPHA AND DETECTION CAPABILITY CCBETA ARE 6.63MICROGL(-1) AND 18.85MICROGL(-1) RESPECTIVELY (WITH PROBABILITIES OF FALSE POSITIVE AND FALSE NEGATIVE FIXED AT 0.05). FINALLY THE PROPOSED METHOD WAS APPLIED TO CARRY OUT A MIGRATION TEST FROM TWO POLYCARBONATE CUPS, USING 3% (W/V) ACETIC ACID IN AQUEOUS SOLUTION AS FOOD SIMULANT. THE MIGRATED AMOUNT OF BPA WAS FOUND TO BE 688.7MICROGL(-1) (N=5) FOR THE FIRST CUP AND 710.5MICROGL(-1) (N=4) FOR THE SECOND ONE, ABOVE THE SPECIFIC MIGRATION LIMIT SET BY EFSA (EUROPEAN FOOD SAFETY AUTHORITY). 2017 9 1470 33 DISTINCT GENE EXPRESSION PROFILES IN IMMORTALIZED HUMAN UROTHELIAL CELLS EXPOSED TO INORGANIC ARSENITE AND ITS METHYLATED TRIVALENT METABOLITES. INORGANIC ARSENIC IS AN ENVIRONMENTAL CARCINOGEN. THE GENERATION OF TOXIC TRIVALENT METHYLATED METABOLITES COMPLICATES THE STUDY OF ARSENIC-MEDIATED CARCINOGENESIS. THIS STUDY SYSTEMATICALLY EVALUATED THE EFFECT OF CHRONIC TREATMENT WITH SODIUM ARSENITE (IAS(III)), MONOMETHYLARSONOUS ACID (MMA(III)), AND DIMETHYLARSINOUS ACID (DMA(III)) ON IMMORTALIZED HUMAN UROEPITHELIAL CELLS (SV-HUC-1 CELLS) USING CDNA MICROARRAY. AFTER EXPOSURE FOR 25 PASSAGES TO IAS(III) (0.5 MICROM), MMA(III) (0.05, 0.1, OR 0.2 MICROM), OR DMA(III) (0.2 OR 0.5 MICROM), SIGNIFICANT COMPOUND-SPECIFIC MORPHOLOGIC CHANGES WERE OBSERVED. A SET OF 114 GENES (5.7% OF THE EXAMINED GENES) WAS DIFFERENTIALLY EXPRESSED IN ONE OR MORE SETS OF ARSENICAL-TREATED CELLS COMPARED WITH UNTREATED CONTROLS. EXPRESSION ANALYSIS SHOWED THAT EXPOSURE OF CELLS TO DMA(III) RESULTED IN A GENE PROFILE DIFFERENT FROM THAT IN CELLS EXPOSED TO IAS(III) OR MMA(III), AND THAT THE IAS(III)-INDUCED GENE PROFILE WAS CLOSEST TO THAT IN THE TUMORIGENIC HUC-1-DERIVED 3-METHYLCHOLANTHRENE-INDUCED TUMORIGENIC CELL LINE MC-SV-HUC T2, WHICH WAS DERIVED FROM SV-HUC-1 CELLS BY METHYLCHOLANTHRENE TREATMENT. OF THE GENES AFFECTED BY ALL THREE ARSENICALS, ONLY ONE, THAT CODING FOR INTERLEUKIN-1 RECEPTOR, TYPE II, SHOWED ENHANCED EXPRESSION, A FINDING CONFIRMED BY THE REDUCED INCREASE IN NF-KAPPAB (NUCLEAR FACTOR KAPPA B) ACTIVITY SEEN IN RESPONSE TO INTERLEUKIN-1BETA IN IAS(III)-EXPOSED CELLS. THE EXPRESSION OF 11 GENES WAS SUPPRESSED BY ALL THREE ARSENICALS. 5-AZA-DEOXYCYTIDINE PARTIALLY RESTORED THE TRANSCRIPTION OF SEVERAL SUPPRESSED GENES, SHOWING THAT EPIGENETIC DNA METHYLATION WAS PROBABLY INVOLVED IN ARSENICAL-INDUCED GENE REPRESSION. OUR DATA DEMONSTRATE THAT CHRONIC EXPOSURE TO IAS(III), MMA(III), OR DMA(III) HAS DIFFERENT EPIGENETIC EFFECTS ON UROTHELIAL CELLS AND REPRESSES NF-KAPPAB ACTIVITY. 2006 10 5555 26 ROLE OF FLUORIDE INDUCED EPIGENETIC ALTERATIONS IN THE DEVELOPMENT OF SKELETAL FLUOROSIS. FLUORIDE IS AN ESSENTIAL TRACE ELEMENT REQUIRED FOR PROPER BONE AND TOOTH DEVELOPMENT. SYSTEMIC HIGH EXPOSURE TO FLUORIDE THROUGH ENVIRONMENTAL EXPOSURE (DRINKING WATER AND FOOD) MAY RESULT IN TOXICITY CAUSING A DISORDER CALLED FLUOROSIS. IN THE PRESENT STUDY, WE INVESTIGATED THE ALTERATION IN DNA METHYLATION PROFILE WITH CHRONIC EXPOSURE (30 DAYS) TO FLUORIDE (8 MG/L) AND ITS RELEVANCE IN THE DEVELOPMENT OF FLUOROSIS. WHOLE GENOME BISULFITE SEQUENCING (WGBS) WAS CARRIED OUT IN HUMAN OSTEOSARCOMA CELLS (HOS) EXPOSED TO FLUORIDE. WHOLE GENOME BISULFITE SEQUENCING (WGBS) AND FUNCTIONAL ANNOTATION OF DIFFERENTIALLY METHYLATED GENES INDICATE ALTERATIONS IN METHYLATION STATUS OF GENES INVOLVED IN BIOLOGICAL PROCESSES ASSOCIATED WITH BONE DEVELOPMENT PATHWAYS. COMBINED ANALYSIS OF PROMOTER DNA HYPER METHYLATION, STRING: FUNCTIONAL PROTEIN ASSOCIATION NETWORKS AND GENE EXPRESSION ANALYSIS REVEALED EPIGENETIC ALTERATIONS IN BMP1, METAP2, MMP11 AND BACH1 GENES, WHICH PLAYS A ROLE IN THE EXTRACELLULAR MATRIX DISASSEMBLY, COLLAGEN CATABOLIC/ORGANIZATION PROCESS, SKELETAL MORPHOGENESIS/DEVELOPMENT, OSSIFICATION AND OSTEOBLAST DEVELOPMENT. THE PRESENT STUDY SHOWS THAT FLUORIDE CAUSES PROMOTER DNA HYPERMETHYLATION IN BMP1, METAP2, MMP11 AND BACH1 GENES WITH SUBSEQUENT DOWN-REGULATION IN THEIR EXPRESSION LEVEL (RNA LEVEL). THE RESULTS IMPLIES THAT FLUORIDE INDUCED DNA HYPERMETHYLATION OF THESE GENES MAY HAMPER EXTRACELLULAR MATRIX DEPOSITION, CARTILAGE FORMATION, ANGIOGENESIS, VASCULAR SYSTEM DEVELOPMENT AND POROSITY OF BONE, THUS PROMOTE SKELETAL FLUOROSIS. 2019 11 1572 24 DNA METHYLATION PATTERNS IN JUVENILE SYSTEMIC SCLEROSIS AND LOCALIZED SCLERODERMA. SCLERODERMA REFERS TO A GROUP OF CHRONIC FIBROTIC IMMUNE-MEDIATED DISEASES OF UNKNOWN ETIOLOGY. CHARACTERIZING EPIGENETIC CHANGES IN CHILDHOOD-ONSET SCLERODERMA, SYSTEMIC SCLEROSIS OR LOCALIZED SCLERODERMA, HAS NOT BEEN PREVIOUSLY PERFORMED. THE AIM OF THIS STUDY WAS TO ASSESS DNA METHYLATION DIFFERENCES AND SIMILARITIES BETWEEN JUVENILE SYSTEMIC SCLEROSIS (JSSC) AND JUVENILE LOCALIZED SCLERODERMA (JLS) COMPARED TO MATCHED HEALTHY CONTROLS. GENOME-WIDE DNA METHYLATION CHANGES IN PERIPHERAL BLOOD MONONUCLEAR CELL SAMPLES WERE ASSESSED USING THE METHYLATIONEPIC ARRAY FOLLOWED BY BIOINFORMATIC ANALYSIS AND LIMITED FUNCTIONAL ASSESSMENT. WE IDENTIFIED A TOTAL OF 105 AND 144 DIFFERENTIALLY METHYLATED SITES COMPARED TO HEALTHY CONTROLS IN JSSC AND JLS, RESPECTIVELY. THE MAJORITY OF DIFFERENTIALLY METHYLATED SITES AND GENES REPRESENTED WERE UNIQUE TO EITHER JSSC OR JLS SUGGESTING A DIFFERENT UNDERLYING EPIGENETIC PATTERN IN BOTH DISEASES. AMONG SHARED DIFFERENTIALLY METHYLATED GENES, METHYLATION LEVELS IN A CPG SITE IN FGFR2 CAN DISTINGUISH BETWEEN LS AND HEALTHY PBMCS WITH A HIGH ACCURACY. CANONICAL PATHWAY ANALYSIS REVEALED THAT INFLAMMATORY PATHWAYS WERE ENRICHED IN GENES DIFFERENTIALLY METHYLATED IN JSSC, INCLUDING STAT3, NF-KAPPAB, AND IL-15 PATHWAYS. IN CONTRAST, THE HIPPO SIGNALING PATHWAY WAS ENRICHED IN JLS. OUR DATA ALSO SUGGEST A POTENTIAL ROLE FOR NOTCH3 IN BOTH JSSC AND JLS, AND REVEALED A NUMBER OF TRANSCRIPTION FACTORS UNIQUE TO EACH OF THE TWO DISEASES. IN SUMMARY, OUR DATA REVEALED IMPORTANT INSIGHTS INTO JSSC AND JLS AND SUGGEST A POTENTIALLY NOVEL EPIGENETIC DIAGNOSTIC BIOMARKER FOR LS. 2021 12 1592 29 DNA METHYLATION PROFILING OF GENOMIC DNA ISOLATED FROM URINE IN DIABETIC CHRONIC KIDNEY DISEASE: A PILOT STUDY. AIM: TO CHARACTERISE THE GENOMIC DNA (GDNA) YIELD FROM URINE AND QUALITY OF DERIVED METHYLATION DATA GENERATED FROM THE WIDELY USED ILLUMINIA INFINIUM METHYLATIONEPIC (HM850K) PLATFORM AND COMPARE THIS WITH BUFFY COAT SAMPLES. BACKGROUND: DNA METHYLATION IS THE MOST WIDELY STUDIED EPIGENETIC MARK AND VARIATIONS IN DNA METHYLATION PROFILE HAVE BEEN IMPLICATED IN DIABETES WHICH AFFECTS APPROXIMATELY 415 MILLION PEOPLE WORLDWIDE. METHODS: QIAAMP VIRAL RNA MINI KIT AND QIAAMP DNA MICRO KIT WERE USED TO EXTRACT DNA FROM FROZEN AND FRESH URINE SAMPLES AS WELL AS INCREASING VOLUMES OF FRESH URINE. MATCHED BUFFY COATS TO THE FROZEN URINE WERE ALSO OBTAINED AND DNA WAS EXTRACTED FROM THE BUFFY COATS USING THE QIAAMP DNA MINI KIT. GENOMIC DNA OF GREATER CONCENTRATION THAN 20MUG/ML WERE USED FOR METHYLATION ANALYSIS USING THE HM850K ARRAY. RESULTS: IRRESPECTIVE OF EXTRACTION TECHNIQUE OR THE USE OF FRESH VERSUS FROZEN URINE SAMPLES, LIMITED GENOMIC DNA WAS OBTAINED USING A STARTING SAMPLE VOLUME OF 5ML (0-0.86MUG/ML). IN ORDER TO OPTIMIZE THE YIELD, WE INCREASED STARTING VOLUMES TO 50ML FRESH URINE, WHICH YIELDED ONLY 0-9.66MUG/ML A DIFFERENT KIT, QIAAMP DNA MICRO KIT, WAS TRIALLED IN SIX FRESH URINE SAMPLES AND TEN FROZEN URINE SAMPLES WITH INADEQUATE DNA YIELDS FROM 0-17.7MUG/ML AND 0-1.6MUG/ML RESPECTIVELY. SUFFICIENT GENOMIC DNA WAS OBTAINED FROM ONLY 4 OF THE INITIAL 41 FROZEN URINE SAMPLES (10%) FOR DNA METHYLATION PROFILING. IN COMPARISON, ALL FOUR BUFFY COAT SAMPLES (100%) PROVIDED SUFFICIENT GENOMIC DNA. CONCLUSION: HIGH QUALITY DATA CAN BE OBTAINED PROVIDED A SUFFICIENT YIELD OF GENOMIC DNA IS ISOLATED. DESPITE OPTIMIZING VARIOUS EXTRACTION METHODOLOGIES, THE MODEST AMOUNT OF GENOMIC DNA DERIVED FROM URINE, MAY LIMIT THE GENERALISABILITY OF THIS APPROACH FOR THE IDENTIFICATION OF DNA METHYLATION BIOMARKERS OF CHRONIC DIABETIC KIDNEY DISEASE. 2018 13 4203 32 METABOLISM OF DOXORUBICIN TO THE CARDIOTOXIC METABOLITE DOXORUBICINOL IS INCREASED IN A MOUSE MODEL OF CHRONIC GLUTATHIONE DEFICIENCY: A POTENTIAL ROLE FOR CARBONYL REDUCTASE 3. DOXORUBICIN IS HIGHLY EFFECTIVE AT INDUCING DNA DOUBLE-STRAND BREAKS IN RAPIDLY DIVIDING CELLS, WHICH HAS LED TO IT BEING A WIDELY USED CANCER CHEMOTHERAPEUTIC. HOWEVER, CLINICAL ADMINISTRATION OF DOXORUBICIN IS LIMITED BY OFF-TARGET CARDIOTOXICITY, WHICH IS THOUGHT TO BE MEDIATED BY DOXORUBICINOL, THE PRIMARY ALCOHOL METABOLITE OF DOXORUBICIN. CARBONYL REDUCTASE 1 (CBR1), A WELL-CHARACTERIZED MONOMERIC ENZYME PRESENT AT HIGH BASAL LEVELS IN THE LIVER, IS KNOWN TO EXHIBIT ACTIVITY TOWARD DOXORUBICIN. LITTLE IS KNOWN ABOUT A CLOSELY RELATED ENZYME, CARBONYL REDUCTASE 3 (CBR3), WHICH IS PRESENT IN THE LIVER AT LOW BASAL LEVELS BUT IS HIGHLY INDUCIBLE BY THE TRANSCRIPTION FACTOR NRF2. GENETIC POLYMORPHISMS IN CBR3, BUT NOT CBR1, ARE ASSOCIATED WITH DIFFERENTIAL CARDIAC OUTCOMES IN DOXORUBICIN TREATED PEDIATRIC PATIENTS. CBR3 MRNA AND CBR3 PROTEIN ARE HIGHLY EXPRESSED IN THE LIVERS OF GCLM-/- MICE (A MOUSE MODEL OF GLUTATHIONE DEFICIENCY) RELATIVE TO WILD TYPE MICE. IN THE PRESENT STUDY, WE FIRST INVESTIGATED THE ABILITY OF CBR3 TO METABOLIZE DOXORUBICIN. INCUBATIONS OF DOXORUBICIN AND PURIFIED RECOMBINANT MURINE CBR3 (MCBR3) WERE ANALYZED FOR DOXORUBICINOL FORMATION USING HPLC, REVEALING FOR THE FIRST TIME THAT DOXORUBICIN IS A SUBSTRATE OF MCBR3. MOREOVER, HEPATOCYTES FROM GCLM-/- MICE PRODUCED MORE DOXORUBICINOL THAN GCLM+/+ HEPATOCYTES. IN ADDITION, DIFFERENTIATED RAT MYOBLASTS (C2C12 CELLS) CO-CULTURED WITH PRIMARY GCLM-/- MURINE HEPATOCYTES WERE MORE SENSITIVE TO DOXORUBICIN-INDUCED CYTOSTASIS/CYTOTOXICITY THAN INCUBATIONS WITH GCLM+/+ HEPATOCYTES. OUR RESULTS INDICATE A POTENTIALLY IMPORTANT ROLE FOR CBR3 IN DOXORUBICIN-INDUCED CARDIOTOXICITY. BECAUSE THERE IS LIKELY TO BE VARIABILITY IN HEPATIC CBR3 ACTIVITY IN HUMANS (DUE TO EITHER GENETIC OR EPIGENETIC INFLUENCES ON ITS EXPRESSION), THESE DATA ALSO SUGGEST THAT INHIBITION OF CBR3 MAY PROVIDE PROTECTION FROM DOXORUBICINOL CARDIOTOXICITY. 2015 14 1471 32 DISTINCT GLOBAL DNA METHYLATION STATUS IN B-CELL LYMPHOMAS: IMMUNOHISTOCHEMICAL STUDY OF 5-METHYLCYTOSINE AND 5-HYDROXYMETHYLCYTOSINE. LYMPHOMAS ARE MALIGNANT NEOPLASMS COMPOSED OF LYMPHOID CELLS AT VARIOUS DEVELOPMENTAL STAGES AND LINEAGES. RECENT ADVANCES IN COMPREHENSIVE GENOMIC ANALYSES IN ACUTE MYELOID LEUKEMIA HAVE REVEALED PREVALENT MUTATIONS IN REGULATORS OF EPIGENETIC PHENOMENA INCLUDING GLOBAL DNA METHYLATION STATUS. THE EXAMPLES INCLUDE MUTATIONS IN ISOCITRATE DEHYDROGENASE 1 (IDH1), IDH2, AND TEN-ELEVEN TRANSLOCATION 2. THESE MUTATIONS ARE PROPOSED TO INHIBIT CONVERSION OF 5-METHYLCYTOSINE (5 MC) TO 5-HYDROXYMETHYLCYTOSINE (5 HMC), LEADING TO GLOBAL ACCUMULATION OF 5 MC. THESE CHANGES IN GLOBAL DNA METHYLATION STATUS CAN BE VISUALIZED IMMUNOHISTOCHEMICALLY USING SPECIFIC ANTIBODIES AGAINST 5 MC AND 5 HMC. WE EXAMINED THE GLOBAL DNA METHYLATION STATUS OF B-CELL LYMPHOMAS AND THAT OF THEIR NORMAL COUNTERPARTS BY IMMUNOHISTOCHEMISTRY FOR 5 MC AND 5 HMC. NON-TUMOR LYMPHOID CELLS INSIDE GERMINAL CENTERS (GC) IN REACTIVE LYMPHOID HYPERPLASIA (RLH) WERE STAINED POSITIVE FOR 5 MC, BUT THEY WERE NEGATIVE FOR 5 HMC. SIMILARLY, FOLLICULAR LYMPHOMAS, WHOSE POSTULATED NORMAL COUNTERPARTS ARE CENTROCYTES IN GCS, WERE 5 MC-POSITIVE BUT 5 HMC-NEGATIVE BY IMMUNOHISTOCHEMISTRY. THIS IMMUNOSTAINING PATTERN WAS ALSO OBSERVED IN BURKITT LYMPHOMA. IN CONTRAST, NON-TUMOR LYMPHOID CELLS IN MANTLE ZONES WERE STAINED POSITIVE FOR 5 MC AS WELL AS FOR 5 HMC. LIKEWISE, MOST MANTLE CELL LYMPHOMAS, WHOSE POSTULATED NORMAL COUNTERPARTS ARE MANTLE ZONE B CELLS IN RLH, WERE STAINED POSITIVE FOR 5 MC AS WELL AS FOR 5 HMC. THIS IMMUNOSTAINING PATTERN WAS ALSO OBSERVED IN CHRONIC LYMPHOCYTIC LEUKEMIA/SMALL LYMPHOCYTIC LYMPHOMA. THESE RESULTS SUGGEST THAT, IN TERMS OF 5 MC/5 HMC IMMUNOHISTOCHEMISTRY, B-CELL LYMPHOMAS WITH DIFFERENT HISTOLOGICAL SUBTYPES ARE ASSOCIATED WITH DISTINCT GLOBAL DNA METHYLATION STATUSES THAT RESEMBLE THOSE OF THEIR POSTULATED NORMAL COUNTERPARTS. 2014 15 1065 30 CLINICAL SIGNIFICANCE OF SERUM DRAM1 MRNA, ARSA MRNA, HSA-MIR-2053 AND LNCRNA-RP1-86D1.3 AXIS EXPRESSION IN MALIGNANT PLEURAL MESOTHELIOMA. AIM AND BACKGROUND: MALIGNANT PLEURAL MESOTHELIOMA (MPM) IS A LETHAL CANCER MAINLY CAUSED BY CHRONIC EXPOSURE OF ASBESTOS. IN THIS PILOT STUDY, WE AIMED TO ASSESS THE EXPRESSION OF SERUM RNA-BASED BIOMARKER PANEL EXPLORING THEIR CLINICAL UTILITY AS DIAGNOSTIC AND PROGNOSTIC BIOMARKERS FOR MPM. METHODS: WE HAVE SELECTED AN MPM-SPECIFIC RNA-BASED BIOMARKER PANEL THROUGH BIOINFORMATICS ANALYSIS BASED ON THE INTEGRATION OF DNA DAMAGE REGULATED AUTOPHAGY MODULATOR 1 (DRAM1) AND ARYLSULFATASE A ( ARSA) GENE EXPRESSION WITH THEIR EPIGENETIC REGULATORS MICRORNA ( MIR-2053) AND LONG NONCODING RNA ( LNCRNA-RP1-86D1.3). THEN, QUANTITATIVE REAL-TIME POLYMERASE CHAIN REACTION (QPCR) VALIDATION IN SERA OF 60 MPM PATIENTS, 20 CHRONIC ASBESTOS EXPOSURE PATIENTS, AND 20 HEALTHY VOLUNTEERS WAS DONE. LASTLY, THE PROGNOSTIC POWER OF THE SELECTED PANEL WAS ASSESSED. RESULTS: THE EXPRESSION OF SERUM DRAM1 MESSENGER RNA (MRNA), ARSA MRNA, HSA-MIR-2053 AND LNCRNA-RP1-86D1.3 WERE POSITIVE IN 78.3%, 90%, 85%, AND 83.3% OF MPM PATIENTS, RESPECTIVELY. THE RNA-BASED BIOMARKER PANEL WAS ABLE TO DISCRIMINATE BETWEEN MPM PATIENTS AND CONTROLS WITH HIGH ACCURACY AND THEIR COMBINED SENSITIVITY REACHED 100% FOR THE DIAGNOSIS OF MPM. KAPLAN-MEIER ANALYSIS SHOWED THAT HSA-MIR-2053 IS AN INDEPENDENT PROGNOSTIC FACTOR OF MPM. CONCLUSION: OUR PRELIMINARY DATA REVEALED THAT THE CHOSEN RNAS PLAY AN IMPORTANT ROLE IN DRIVING MPM DEVELOPMENT AND PROGRESSION. 2019 16 3552 18 IMMUNOSUPPRESSION BY CHRONIC EXPOSURE TO N-NITROSODIMETHYLAMINE (NDMA) IN MICE. IMMUNOSUPPRESSION OF HUMORAL AND CELLULAR RESPONSES FOLLOWING CHRONIC ORAL EXPOSURE TO 1, 5, 10, AND 20 PPM N-NITROSODIMETHYLAMINE (NDMA) WAS EXAMINED IN CD-1 MICE. MONITORING OF CUMULATIVE MORTALITY AND THE INCIDENCE OF PERITONEAL ASCITES IN ANIMALS SHOWED AN NDMA DOSE-RELATED MORTALITY AND HEPATOTOXICITY. NO VISIBLE CHANGES IN IMMUNOLOGICAL PARAMETERS WERE NOTED AT THE 1 PPM NDMA DOSE. IMMUNOSUPPRESSION OF IMMUNOGLOBULIN M (IGM) ANTIBODY RESPONSE BY NDMA TO SHEEP RED BLOOD CELLS (SRBC) WAS TIME-RELATED, DOSE-RELATED, AND COULD BE REVERSED WITHIN 30 D BY REMOVAL OF THE CHEMICAL FROM THE DRINKING WATER. CELLULAR IMMUNE RESPONSE, MONITORED BY ALLOGENEIC STIMULATION OF CELLS IN MIXED LYMPHOCYTE REACTION (MLR), WAS MARKEDLY SUPPRESSED BY 10 AND 20 PPM NDMA. THUS, CHRONIC EXPOSURE TO NDMA, EXCEPT FOR THE LOW-HEPATOTOXIC DOSES OF NITROSAMINE, RESULTED IN A MARKED AND PERSISTENT IMMUNOSUPPRESSION OF CELLULAR AND HUMORAL RESPONSES IN CD-1 MICE. IN CONCLUSION, CHRONIC EXPOSURE TO THE HEPATOTOXIC (ASCITE-INDUCING) DOSES OF NDMA SUPPRESSED HUMORAL AND CELLULAR IMMUNITY. THE PERSISTENT IMMUNOSUPPRESSION COULD BE REVERSED AFTER THE REMOVAL OF NDMA FROM THE DRINKING WATER. ALTHOUGH NO DIRECT NDMA-RELATED CANCER WAS REPORTED IN HUMANS, OUR DATA POINT TO A POTENTIAL EPIGENETIC CARCINOGENICITY OF NITROSAMINES DUE TO CHRONIC IMMUNOSUPPRESSION. 1992 17 2311 33 EPIGENETIC REGULATION OF CYTOSOLIC PHOSPHOLIPASE A2 IN SH-SY5Y HUMAN NEUROBLASTOMA CELLS. GROUP IVA CYTOSOLIC PHOSPHOLIPASE A2 (CPLA2 OR PLA2G4A) IS A KEY ENZYME THAT CONTRIBUTES TO INFLAMMATION VIA THE GENERATION OF ARACHIDONIC ACID AND EICOSANOIDS. WHILE MUCH IS KNOWN ABOUT REGULATION OF CPLA2 BY POSTTRANSLATIONAL MODIFICATION SUCH AS PHOSPHORYLATION, LITTLE IS KNOWN ABOUT ITS EPIGENETIC REGULATION. IN THIS STUDY, TREATMENT WITH HISTONE DEACETYLASE (HDAC) INHIBITORS, TRICHOSTATIN A (TSA), VALPROIC ACID, TUBACIN AND THE CLASS I HDAC INHIBITOR, MS-275, WERE FOUND TO INCREASE CPLA2ALPHA MESSENGER RNA (MRNA) EXPRESSION IN SH-SY5Y HUMAN NEUROBLASTOMA CELLS. CO-TREATMENT OF THE HISTONE ACETYLTRANSFERASE (HAT) INHIBITOR, ANACARDIC ACID, MODULATED UPREGULATION OF CPLA2ALPHA INDUCED BY TSA. SPECIFIC INVOLVEMENT OF CLASS I HDACS AND HAT IN CPLA2ALPHA REGULATION WAS FURTHER SHOWN, AND A TIP60-SPECIFIC HAT INHIBITOR, NU9056, MODULATED THE UPREGULATION OF CPLA2ALPHA INDUCED BY MS-275. IN ADDITION, CO-TREATMENT OF WITH HISTONE METHYLTRANSFERASE (HMT) INHIBITOR, 5'-DEOXY-5'-METHYLTHIOADENOSINE (MTA) SUPPRESSED TSA-INDUCED CPLA2ALPHA UPREGULATION. THE ABOVE CHANGES IN CPLA2 MRNA EXPRESSION WERE REFLECTED AT THE PROTEIN LEVEL BY WESTERN BLOTS AND IMMUNOCYTOCHEMISTRY. CHROMATIN IMMUNOPRECIPITATION (CHIP) SHOWED TSA INCREASED BINDING OF TRIMETHYLATED H3K4 TO THE PROXIMAL PROMOTER REGION OF THE CPLA2ALPHA GENE. CELL INJURY AFTER TSA TREATMENT AS INDICATED BY LACTATE DEHYDROGENASE (LDH) RELEASE WAS MODULATED BY ANACARDIC ACID, AND A ROLE OF CPLA2 IN MEDIATING TSA-INDUCED INJURY SHOWN, AFTER CO-INCUBATION WITH THE CPLA2 SELECTIVE INHIBITOR, ARACHIDONOYL TRIFLUOROMETHYL KETONE (AACOCF3). TOGETHER, RESULTS INDICATE EPIGENETIC REGULATION OF CPLA2 AND THE POTENTIAL OF SUCH REGULATION FOR TREATMENT OF CHRONIC INFLAMMATION. 2016 18 192 30 ACETYLATED H4K16 BY MYST1 PROTECTS UROTSA CELLS FROM ARSENIC TOXICITY AND IS DECREASED FOLLOWING CHRONIC ARSENIC EXPOSURE. ARSENIC, A HUMAN CARCINOGEN THAT IS ASSOCIATED WITH AN INCREASED RISK OF BLADDER CANCER, IS COMMONLY FOUND IN DRINKING WATER. AN IMPORTANT MECHANISM BY WHICH ARSENIC IS THOUGHT TO BE CARCINOGENIC IS THROUGH THE INDUCTION OF EPIGENETIC CHANGES THAT LEAD TO ABERRANT GENE EXPRESSION. PREVIOUSLY, WE REPORTED THAT THE SAS2 GENE IS REQUIRED FOR OPTIMAL GROWTH OF YEAST IN THE PRESENCE OF ARSENITE (AS(III)). YEAST SAS2P IS ORTHOLOGOUS TO HUMAN MYST1, A HISTONE 4 LYSINE 16 (H4K16) ACETYLTRANSFERASE. HERE, WE SHOW THAT H4K16 ACETYLATION IS NECESSARY FOR THE RESISTANCE OF YEAST TO AS(III) THROUGH THE MODULATION OF CHROMATIN STATE. WE FURTHER EXPLORED THE ROLE OF MYST1 AND H4K16 ACETYLATION IN ARSENIC TOXICITY AND CARCINOGENESIS IN HUMAN BLADDER EPITHELIAL CELLS. THE EXPRESSION OF MYST1 WAS KNOCKED DOWN IN UROTSA CELLS, A MODEL OF BLADDER EPITHELIUM THAT HAS BEEN USED TO STUDY ARSENIC-INDUCED CARCINOGENESIS. SILENCING OF MYST1 REDUCED ACETYLATION OF H4K16 AND INDUCED SENSITIVITY TO AS(III) AND TO ITS MORE TOXIC METABOLITE MONOMETHYLARSONOUS ACID (MMA(III)) AT DOSES RELEVANT TO HIGH ENVIRONMENTAL HUMAN EXPOSURES. IN ADDITION, BOTH AS(III) AND MMA(III) TREATMENTS DECREASED GLOBAL H4K16 ACETYLATION LEVELS IN A DOSE- AND TIME-DEPENDENT MANNER. THIS INDICATES THAT ACETYLATED H4K16 IS REQUIRED FOR RESISTANCE TO ARSENIC AND THAT A REDUCTION IN ITS LEVELS AS A CONSEQUENCE OF ARSENIC EXPOSURE MAY CONTRIBUTE TO TOXICITY IN UROTSA CELLS. BASED ON THESE FINDINGS, WE PROPOSE A NOVEL ROLE FOR THE MYST1 GENE IN HUMAN SENSITIVITY TO ARSENIC. 2009 19 2464 33 EPIGENETIC THERAPY USING BELINOSTAT FOR PATIENTS WITH UNRESECTABLE HEPATOCELLULAR CARCINOMA: A MULTICENTER PHASE I/II STUDY WITH BIOMARKER AND PHARMACOKINETIC ANALYSIS OF TUMORS FROM PATIENTS IN THE MAYO PHASE II CONSORTIUM AND THE CANCER THERAPEUTICS RESEARCH GROUP. PURPOSE: EPIGENETIC ABERRATIONS HAVE BEEN REPORTED IN HEPATOCELLULAR CARCINOMA (HCC). IN THIS STUDY OF PATIENTS WITH UNRESECTABLE HCC AND CHRONIC LIVER DISEASE, EPIGENETIC THERAPY WITH THE HISTONE DEACETYLASE INHIBITOR BELINOSTAT WAS ASSESSED. THE OBJECTIVES WERE TO DETERMINE DOSE-LIMITING TOXICITY AND MAXIMUM-TOLERATED DOSE (MTD), TO ASSESS PHARMACOKINETICS IN PHASE I, AND TO ASSESS ACTIVITY OF AND EXPLORE POTENTIAL BIOMARKERS FOR RESPONSE IN PHASE II. PATIENTS AND METHODS: MAJOR ELIGIBILITY CRITERIA INCLUDED HISTOLOGICALLY CONFIRMED UNRESECTABLE HCC, EUROPEAN COOPERATIVE ONCOLOGY GROUP PERFORMANCE SCORE