1 813 157 CHANGES IN POLY(ADP-RIBOSYL)ATION PATTERNS IN WORKERS EXPOSED TO BTX. OCCUPATIONAL EXPOSURE TO (BENZENE, TOLUENE AND XYLENE, BTX IS COMMON IN THE CHINESE WORKPLACE. CHRONIC OCCUPATIONAL EXPOSURE TO BENZENE IS ASSOCIATED WITH AN INCREASED RISK OF HEMATOLOGICAL MALIGNANCIES SUCH AS ACUTE MYELOID LEUKEMIA (AML), BUT THE UNDERLYING MECHANISMS ARE STILL UNCLEAR. THIS STUDY INVESTIGATES CHANGES IN POLY(ADP-RIBOSYL)ATION AND DNA METHYLATION IN SUBJECTS OCCUPATIONALLY EXPOSED TO A BTX. BLOOD DNA SAMPLES AND EXPOSURE DATA WERE OBTAINED FROM SUBJECTS WITH DIFFERENT LEVELS OF EXPOSURE, INCLUDING 132 DECORATORS, 129 PAINTERS, AND 130 UNEXPOSED REFERENTS IN A CONTAINER-MANUFACTURING FACTORY IN SHENZHEN, CHINA. OCCUPATIONAL EXPOSURE ASSESSMENT INCLUDED PERSONAL MONITORING OF AIRBORNE BENZENE, TOLUENE AND XYLENE. HEMATOLOGICAL PARAMETERS WERE MEASURED AND THE CYTOKINESIS-BLOCK MICRONUCLEUS (CBMN) ASSAY WAS USED TO DETECT DNA DAMAGE IN PERIPHERAL LYMPHOCYTES. QUANTITATIVE REAL-TIME PCR WAS USED TO DETECT THE MRNA EXPRESSION OF POLY(ADP-RIBOSE) POLYMERASE 1 (PARP1) AND POLY(ADP-RIBOSE) GLYCOHYDROLASE (PARG), DNA METHYLTRANSFERASES (DNMTS) INCLUDING DNMT1, DNMT3A AND DNMT3B, METHYL-CPG-BINDING DOMAIN PROTEIN 2(MBD2). PARP1 ASSAY WAS USED TO MEASURE PARP ACTIVITY. AIRBORNE LEVELS OF BENZENE, TOLUENE AND XYLENE IN THE TWO EXPOSED GROUPS WERE SIGNIFICANTLY HIGHER THAN THOSE OF CONTROLS (P<0.001). THE TWO EXPOSED GROUPS (DECORATORS, PAINTERS) SHOWED DECREASED PARP1, DNMTS AND MBD2 EXPRESSION RELATIVE TO CONTROLS (P<0.05), AND PARP ACTIVITY WAS ALSO DECREASED (P<0.05). DECREASED PARP1, DNMT1, DNMT3A, DNMT3B AND MBD2 MRNA EXPRESSION WAS CORRELATED WITH INCREASED AIRBORNE BTX (PEARSON'S R: -0.587, -0.314, -0.636, -0.567 AND -0.592 RESPECTIVELY, P<0.001). NO SIGNIFICANT DIFFERENCES IN HEMATOLOGICAL PARAMETERS AND CBMN WERE FOUND AMONG THE THREE GROUPS. TOGETHER, THESE RESULTS SUGGEST THAT DECREASED DNMTS, MBD2 AND PARP1 MIGHT BE INVOLVED IN THE GLOBAL HYPOMETHYLATION ASSOCIATED WITH BTX EXPOSURE, AND THE IMBALANCE OF PARP/PARG MIGHT PARTICIPATE IN THE DOWN-REGULATION OF DNMTS. THIS IS THE FIRST HUMAN STUDY TO LINK ALTERED POLY(ADP-RIBOSYL)ATION PATTERNS, WHICH REPRODUCE THE ABERRANT EPIGENETIC PATTERNS FOUND IN BENZENE-TREATED CELLS, TO CHRONIC OCCUPATIONAL EXPOSURE TO BTX. 2014 2 3441 48 HYPERMETHYLATION IN GENE PROMOTERS ARE INDUCED BY CHRONIC EXPOSURE TO BENZENE, TOLUENE, ETHYLBENZENE AND XYLENES. BACKGROUND AND OBJECTIVE: GAS STATION ATTENDANTS ARE OCCUPATIONALLY EXPOSED TO BENZENE, TOLUENE, ETHYLBENZENE AND XYLENE (BTEX) COMPOUNDS AND THUS MORE SUSCEPTIBLE TO THE BIOLOGICAL EFFECTS OF THIS MIXTURE PRESENT IN GASOLINE, ESPECIALLY DUE TO THE CARCINOGENICITY OF BENZENE. FURTHERMORE, THE HARMFUL EFFECTS OF BTEX EXPOSURE MAY BE POTENTIATED BY GENETIC AND EPIGENETIC INACTIVATION OF CRITICAL GENES. THE OBJECTIVE WAS TO EVALUATE SUCH GENE-BTEX INTERACTIONS ACCESSING THE PROMOTER METHYLATION STATUS OF P14ARF, P16INK4A AND GSTP1 IN PERIPHERAL BLOOD LEUKOCYTE SAMPLES. MATERIALS AND METHODS: THE 59 EXPOSED AND 68 UNEXPOSED PARTICIPANTS FROM RIO DE JANEIRO, BRAZIL, WERE INCLUDED. THE PROMOTER METHYLATION STATUS WAS ACCESSED BY METHYLATION-SPECIFIC PCR (MSP) AND GSTP1 ILE105VAL POLYMORPHISM WAS INVESTIGATED BY PCR-RESTRICTION FRAGMENT LENGTH POLYMORPHISM (PCR-RFLP) TECHNIQUE. RESULTS: BOTH P14ARF AND P16INK4A WERE SIGNIFICANTLY HYPERMETHYLATED IN EXPOSED SUBJECTS COMPARED TO UNEXPOSED (P = 0.004 AND P<0.001, RESPECTIVELY). ADDITIONALLY, P16INK4A HYPERMETHYLATION IN THE EXPOSED GROUP WAS CORRELATED WITH CHROMOSOMAL ABNORMALITIES (CAS) (P = 0.018), THUS HIGHLIGHTING THE INFLUENCE OF THE GENE-ENVIRONMENT INTERACTIONS ON GENOME INSTABILITY. NOTEWORTHY, P16INK4A METHYLATION WAS SIGNIFICANTLY ASSOCIATED WITH MISCARRIAGE AMONG FEMALE ATTENDANTS (P = 0.047), IN WHICH THOSE WHO REPORTED MISCARRIAGE EXHIBITED HYPERMETHYLATION IN AT LEAST 2 OF THE 3 GENES ANALYZED. THE GSTP1 HETEROZYGOTE GENOTYPE, WHICH COULD AFFECT THE METABOLISM OF BENZENE DETOXIFICATION, WAS FOUND IN BOTH GROUPS BUT WAS MORE FREQUENT IN THOSE OCCUPATIONALLY EXPOSED. NO SIGNIFICANT ASSOCIATION WAS OBSERVED BETWEEN GSTP1 GENOTYPES AND METHYLATION STATUS. CONCLUSION: TOGETHER, THESE FINDINGS INDICATE THAT GAS STATION ATTENDANTS WITH THE AFOREMENTIONED EPIGENETIC AND GENETIC PROFILES MAY BE AT GREATER RISK OF OCCUPATIONAL BTEX EXPOSURE-INDUCED GENOME INSTABILITY, WHICH COULD REQUIRE CONCERTED EFFORTS TO ESTABLISH MORE PREVENTIVE ACTIONS AND CONSTANT BIOMONITORING IN GAS STATION ATTENDANTS. 2020 3 5683 45 SHORTER TELOMERE LENGTH IN PERIPHERAL BLOOD LYMPHOCYTES OF WORKERS EXPOSED TO POLYCYCLIC AROMATIC HYDROCARBONS. SHORTER TELOMERE LENGTH (TL) IN PERIPHERAL BLOOD LYMPHOCYTES (PBLS) IS PREDICTIVE OF LUNG CANCER RISK. POLYCYCLIC AROMATIC HYDROCARBONS (PAHS) ARE ESTABLISHED LUNG CARCINOGENS THAT CAUSE CHROMOSOME INSTABILITY. WHETHER PAH EXPOSURE AND ITS MOLECULAR EFFECTS ARE LINKED WITH SHORTER TL HAS NEVER BEEN EVALUATED. IN THE PRESENT STUDY, WE INVESTIGATED THE EFFECT OF CHRONIC EXPOSURE TO PAHS ON TL MEASURED IN PBLS OF POLISH MALE NON-CURRENT SMOKING COKEOVEN WORKERS AND MATCHED CONTROLS. PAH EXPOSURE AND MOLECULAR EFFECTS WERE CHARACTERIZED USING MEASURES OF INTERNAL DOSE (URINARY 1-PYRENOL), EFFECTIVE DOSE [ANTI-BENZO[A]PYRENE DIOLEPOXIDE (ANTI-BPDE)-DNA ADDUCT], GENETIC INSTABILITY (MICRONUCLEI, MN) AND DNA METHYLATION [P53 PROMOTER AND ALU AND LONG INTERSPERSED NUCLEAR ELEMENT-1 (LINE-1) REPETITIVE ELEMENTS, AS SURROGATE MEASURES OF GLOBAL METHYLATION] IN PBLS. TL WAS MEASURED BY REAL-TIME POLYMERASE CHAIN REACTION. COKEOVEN WORKERS WERE HEAVILY EXPOSED TO PAHS (79% EXCEEDED THE URINARY 1-PYRENOL BIOLOGICAL EXPOSURE INDEX) AND EXHIBITED LOWER TL (P = 0.038) THAN CONTROLS, AS WELL AS HIGHER LEVELS OF GENETIC AND CHROMOSOMAL ALTERATIONS [I.E. ANTI-BPDE-DNA ADDUCT AND MN (P < 0.0001)] AND EPIGENETIC CHANGES [I.E. P53 GENE-SPECIFIC PROMOTER AND GLOBAL METHYLATION (P /=65%), PRF1 EXPRESSION WAS SIGNIFICANTLY LOWER IN CFS THAN NF SUBJECTS IMMEDIATELY FOLLOWING TSST. THESE FINDINGS SUGGEST METHYLATION COULD BE AN IMPORTANT EPIGENETIC DETERMINANT OF INTER-INDIVIDUAL DIFFERENCES IN PRF1 EXPRESSION AND THAT THE DIFFERENCES IN PRF1 EXPRESSION AND METHYLATION BETWEEN CFS AND NF IN THE ACUTE STRESS RESPONSE REQUIRE FURTHER INVESTIGATION. 2013 9 4378 38 MITOCHONDRIAL DNA COPY NUMBER AND EXPOSURE TO POLYCYCLIC AROMATIC HYDROCARBONS. BACKGROUND: INCREASED MITOCHONDRIAL DNA COPY NUMBER (MTDNACN) IS A BIOLOGIC RESPONSE TO MTDNA DAMAGE AND DYSFUNCTION, PREDICTIVE OF LUNG CANCER RISK. POLYCYCLIC AROMATIC HYDROCARBONS (PAHS) ARE ESTABLISHED LUNG CARCINOGENS AND MAY CAUSE MITOCHONDRIAL TOXICITY. WHETHER PAH EXPOSURE AND PAH-RELATED NUCLEAR DNA (NDNA) GENOTOXIC EFFECTS ARE LINKED WITH INCREASED MTDNACN HAS NEVER BEEN EVALUATED. METHODS: WE INVESTIGATED THE EFFECT OF CHRONIC EXPOSURE TO PAHS ON MTDNACN IN PERIPHERAL BLOOD LYMPHOCYTES (PBLS) OF 46 POLISH MALE NONCURRENT SMOKING COKE-OVEN WORKERS AND 44 MATCHED CONTROLS, WHO WERE PART OF A GROUP OF 94 STUDY INDIVIDUALS EXAMINED IN OUR PREVIOUS WORK. SUBJECTS' PAH EXPOSURE AND GENETIC ALTERATIONS WERE CHARACTERIZED THROUGH MEASURES OF INTERNAL DOSE (URINARY 1-PYRENOL), TARGET DOSE [ANTI-BENZO[A]PYRENE DIOLEPOXIDE (ANTI-BPDE)-DNA ADDUCT], GENETIC INSTABILITY (MICRONUCLEI AND TELOMERE LENGTH), AND DNA METHYLATION (P53 PROMOTER) IN PBLS. MTDNACN (MT/S) WAS MEASURED USING A VALIDATED REAL-TIME PCR METHOD. RESULTS: WORKERS WITH PAH EXPOSURE ABOVE THE MEDIAN VALUE (>3 MUMOL 1-PYRENOL/MOL CREATININE) SHOWED HIGHER MTDNACN [GEOMETRIC MEANS (GM) OF 1.06 (UNADJUSTED) AND 1.07 (AGE-ADJUSTED)] COMPARED WITH CONTROLS [GM 0.89 (UNADJUSTED); 0.89 (AGE-ADJUSTED); (P = 0.029 AND 0.016)], AS WELL AS HIGHER LEVELS OF GENETIC AND CHROMOSOMAL [I.E., ANTI-BPDE-DNA ADDUCTS (P < 0.001), MICRONUCLEI (P < 0.001), AND TELOMERE LENGTH (P = 0.053)] AND EPIGENETIC [I.E., P53 GENE-SPECIFIC PROMOTER METHYLATION (P < 0.001)] ALTERATIONS IN THE NDNA. IN THE WHOLE STUDY POPULATION, UNADJUSTED AND AGE-ADJUSTED MTDNACN WAS POSITIVELY CORRELATED WITH 1-PYRENOL (P = 0.043 AND 0.032) AND ANTI-BPDE-DNA ADDUCTS (P = 0.046 AND 0.049). CONCLUSIONS: PAH EXPOSURE AND PAH-RELATED NDNA GENOTOXICITY ARE ASSOCIATED WITH INCREASED MTDNACN. IMPACT: THE PRESENT STUDY IS SUGGESTIVE OF POTENTIAL ROLES OF MTDNACN IN PAH-INDUCED CARCINOGENESIS. 2013 10 1264 45 CYP2E1 EPIGENETIC REGULATION IN CHRONIC, LOW-LEVEL TOLUENE EXPOSURE: RELATIONSHIP WITH OXIDATIVE STRESS AND SMOKING HABIT. BACKGROUND: CYP2E1 IS A VERSATILE PHASE I DRUG-METABOLIZING ENZYME RESPONSIBLE FOR THE BIOTRANSFORMATION OF MOST VOLATILE ORGANIC COMPOUNDS, INCLUDING TOLUENE. HUMAN TOLUENE EXPOSURE INCREASES CYP2E1 MRNA AND MODIFIES ITS ACTIVITY IN LEUCOCYTES; HOWEVER, EPIGENETIC IMPLICATIONS OF THIS INTERACTION HAVE NOT BEEN INVESTIGATED. GOAL: TO DETERMINE PROMOTER METHYLATION OF CYP2E1 AND OTHER GENES KNOWN TO BE AFFECTED BY TOLUENE EXPOSURE. METHODS: WE OBTAINED VENOUS BLOOD FROM 24 TANNERY WORKERS EXPOSED TO TOLUENE (MEAN LEVELS: 10.86+/-7MG/M(3)) AND 24 ADMINISTRATIVE WORKERS (REFERENCE GROUP, MEAN LEVELS 0.21+/-0.02MG/M(3)) ALL OF THEM FROM THE CITY OF LEON, GUANAJUATO, MEXICO. AFTER DNA EXTRACTION AND BISULFITE TREATMENT, WE PERFORMED PCR-PYROSEQUENCING IN ORDER TO MEASURE METHYLATION LEVELS AT PROMOTER REGION OF 13 GENES. RESULTS: IN EXPOSED GROUP WE FOUND SIGNIFICANT CORRELATIONS BETWEEN TOLUENE AIRBORNE LEVELS AND CYP2E1 PROMOTER METHYLATION (R=-.36, P<0.05), AS WELL AS FOR IL6 PROMOTER METHYLATION LEVELS (R=.44, P<0.05). MOREOVER, CYP2E1 PROMOTER METHYLATION LEVELS WHERE HIGHER IN TOLUENE-EXPOSED SMOKERS COMPARED TO NONSMOKERS (P=0.009). WE ALSO OBSERVED SIGNIFICANT CORRELATIONS FOR CYP2E1 PROMOTER METHYLATION WITH GSTP1 AND SOD1 PROMOTER METHYLATION LEVELS (R=-.37, P<0.05 AND R=-.34, P<0.05 RESPECTIVELY). CONCLUSION: THESE RESULTS HIGHLIGHT THE IMPORTANCE OF CONSIDERING CYP2E1 EPIGENETIC MODIFICATIONS, AS WELL AS ITS INTERACTIONS WITH OTHER GENES, AS KEY FACTORS FOR UNRAVELING THE SUB CELLULAR MECHANISMS OF TOXICITY EXERTED BY OXIDATIVE STRESS, WHICH CAN INITIATE DISEASE PROCESS IN CHRONIC, LOW-LEVEL TOLUENE EXPOSURE. PEOPLE CO-EXPOSED TO TOLUENE AND TOBACCO SMOKE ARE IN HIGHER RISK DUE TO A POSSIBLE CYP2E1 REPRESSION. 2015 11 6492 42 TRAFFIC-RELATED AIR POLLUTION AND GROUND-LEVEL OZONE ASSOCIATED GLOBAL DNA HYPOMETHYLATION AND BULKY DNA ADDUCT FORMATION. STUDIES HAVE INDICATED THAT AIR POLLUTION, INCLUDING SURFACE-LEVEL OZONE (O(3)), CAN SIGNIFICANTLY INFLUENCE THE RISK OF CHRONIC DISEASES. TO BETTER UNDERSTAND THE CARCINOGENIC MECHANISMS OF AIR POLLUTANTS AND IDENTIFY PREDICTIVE DISEASE BIOMARKERS, WE EXAMINED THE ASSOCIATION BETWEEN TRAFFIC-RELATED POLLUTANTS WITH DNA METHYLATION ALTERATIONS AND BULKY DNA ADDUCTS, TWO BIOMARKERS OF CARCINOGEN EXPOSURE AND CANCER RISK, IN THE PERIPHERAL BLOOD OF 140 VOLUNTEERS-95 TRAFFIC POLICE OFFICERS, AND 45 UNEXPOSED SUBJECTS. THE DNA METHYLATION AND ADDUCT MEASUREMENTS WERE PERFORMED BY BISULFITE-PCR AND PYROSEQUENCING AND (32)P-POSTLABELING ASSAY. AIRBORNE LEVELS OF BENZO(A)PYRENE [B(A)P], CARBON MONOXIDE, AND TROPOSPHERIC O(3) WERE DETERMINED BY PERSONAL EXPOSURE BIOMONITORING OR BY FIXED MONITORING STATIONS. OVERALL, AIR POLLUTION EXPOSURE WAS ASSOCIATED WITH A SIGNIFICANT REDUCTION (1.41 UNITS) IN GLOBAL DNA METHYLATION (95% C.I. -2.65-0.04, P = 0.026). THE DECREMENT IN ALU REPETITIVE ELEMENTS WAS GREATEST IN THE POLICEMEN WORKING DOWNTOWN (95% C.I. -3.23--0.49, P = 0.008). THE DNA ADDUCTS WERE FOUND TO BE SIGNIFICANTLY INCREASED (0.45 UNITS) IN THE MUNICIPAL OFFICERS WITH RESPECT TO UNEXPOSED SUBJECTS (95% C.I. 0.02-0.88, P = 0.039), MAINLY IN THOSE WHO WERE CONTROLLING TRAFFIC IN DOWNTOWN AREAS (95% C.I. 0.39-1.29, P < 0.001). REGRESSION MODELS INDICATED AN INCREMENT OF ALU METHYLATION AT HIGHER B(A)P CONCENTRATIONS (95% C.I. 0.03-0.60, P = 0.032). MOREOVER, STATISTICAL MODELS SHOWED A DECREMENT IN ALU METHYLATION AND AN INCREMENT OF DNA DAMAGE ONLY ABOVE THE CUT-OFF VALUE OF 30 MICROG/M(3) O(3). A SIGNIFICANT INCREMENT OF 0.73 UNITS OF IL-6 GENE METHYLATION WAS ALSO FOUND IN SMOKERS WITH RESPECT TO NON-SMOKERS. OUR RESULTS HIGHLIGHTED THE ROLE OF AIR POLLUTION ON EPIGENETIC ALTERATIONS AND GENOTOXIC EFFECTS, ESPECIALLY ABOVE THE TARGET VALUE OF 30 MICROG/M(3) SURFACE-LEVEL O(3), SUPPORTING THE NECESSITY FOR DEVELOPING PUBLIC HEALTH STRATEGIES AIMED TO REDUCE TRAFFIC-RELATED AIR POLLUTION MOLECULAR ALTERATIONS. 2023 12 6415 39 THE STUDY OF P16 AND P15 GENE METHYLATION IN HEAD AND NECK SQUAMOUS CELL CARCINOMA AND THEIR QUANTITATIVE EVALUATION IN PLASMA BY REAL-TIME PCR. EPIGENETIC SILENCING OF THE P16 AND P15 GENES BY PROMOTER METHYLATION ARE COMMONLY OBSERVED IN HUMAN EPITHELIAL MALIGNANCIES, INCLUDING HEAD AND NECK SQUAMOUS CELL CARCINOMAS (HNSCC). IN THIS STUDY, A METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION (MSP) WAS USED TO EVALUATE THE METHYLATION STATUS OF THE P16 AND P15 GENES IN 73 HNSCC SURGICAL SPECIMENS. P16 AND P15 GENE METHYLATION WAS ALSO EXAMINED IN 29 PAIRED METASTATIC LYMPH NODES AND 29 PAIRED HISTOLOGICALLY, NORMAL RESECTION MARGIN MUCOSAE. THE QUANTITY OF CELL-FREE METHYLATED P16 AND P15 DNA IN THE PLASMA SAMPLES OF 20 HNSCC PATIENTS AND 24 HEALTHY CONTROLS WAS ALSO EXAMINED USING A FLUORESCENCE-BASED REAL-TIME PCR ASSAY. THE FREQUENCIES OF P16 AND P15 METHYLATION IN THE PRIMARY TUMOUR WERE 49% AND 60%, RESPECTIVELY. CONCORDANT METHYLATION OF P16 AND P15 IN TUMOUR SAMPLES AND METASTATIC LYMPH NODES WAS FOUND IN 59 AND 38% OF CASES, RESPECTIVELY. A SIGNIFICANTLY HIGHER PREVALENCE OF P15 METHYLATION WAS FOUND IN HISTOLOGICALLY-NORMAL SURGICAL MARGIN EPITHELIA OF HNSCC PATIENTS WITH CHRONIC SMOKING AND DRINKING HABITS COMPARED WITH NON-SMOKERS AND NON-DRINKERS. IN ADDITION, METHYLATED P16 AND P15 DNA LEVELS WERE SIGNIFICANTLY HIGHER IN THE PLASMA OF HNSCC PATIENTS (MEAN 56 COPIES/ML PLASMA AND 65 COPIES/ML PLASMA, RESPECTIVELY) COMPARED WITH NORMAL CONTROLS (MEAN 6 COPIES/ML PLASMA AND 16 COPIES/ML PLASMA, RESPECTIVELY). IN CONCLUSION, PROMOTER METHYLATION OF THE P16 AND P15 GENES IS INVOLVED IN THE PATHOGENESIS OF HNSCC AND MAY BE RELATED TO CHRONIC SMOKING AND DRINKING. THE DIFFERENTIAL LEVELS OF METHYLATED P16 AND P15 DNA IN PLASMA MIGHT BE POTENTIAL USEFUL MARKERS IN SCREENING HIGH-RISK POPULATIONS FOR EARLY HNSCC AND MONITORING THEIR TREATMENT RESPONSE. 2003 13 4601 41 NDRG2 MRNA LEVELS AND MIR-28-5P AND MIR-650 ACTIVITY IN CHRONIC LYMPHOCYTIC LEUKEMIA. BACKGROUND: NDRG2 IS IDENTIFIED AS A TUMOR SUPPRESSOR GENE IN MANY TUMORS, AND FUNCTIONS IN CELL PROLIFERATION, DIFFERENTIATION AND APOPTOSIS. RECENT DATA INDICATE THAT NDRG2 EXPRESSION IS UP-REGULATED BY TP53. MOREOVER, PROPOSED MECHANISMS OF NDRG2 INACTIVATION INCLUDE EPIGENETIC SILENCING OF THE NDRG2 PROMOTER AND DOWN-REGULATION BY MICRORNAS (MIRNAS). HOWEVER, FEW STUDIES HAVE EVER BEEN DONE ON THE ROLE OF NDRG2 AND THE NDRG2-REGULATING MIRNAS INTERFERENCE IN CHRONIC LYMPHOCYTIC LEUKEMIA (CLL). METHODS: NDRG2 AND MICRORNAS MRNA LEVELS IN CLL SUBJECTS WERE ASSESSED BY QUANTITATIVE REAL-TIME POLYMERASE CHAIN REACTION (QRT-PCR). THE DUAL-LUCIFERASE REPORTER ASSAY WAS PERFORMED TO DETERMINE NDRG2-RELATED MIRNAS. LOW EXPRESSION OF MATURE EXOGENOUS MIRNAS IN CLL CELLS WAS ESTABLISHED BY TRANSIENT TRANSFECTION. NDRG2 PROTEIN LEVELS IN CLL CELLS WERE DETECTED BY WESTERN BLOT. IN ADDITION, FLOW CYTOMETRY WAS CONDUCTED TO EXAMINE THE APOPTOSIS OF CLL CELLS. RESULTS: LOWER EXPRESSION OF NDRG2 WAS FOUND IN THE B-CELLS FROM 102 CLL PATIENTS COMPARED THE 40 NORMAL SUBJECTS (P < 0.001). PATIENTS WITH ADVANCED BINET STAGE (P = 0.001), HIGH LACTATE DEHYDROGENASE (LDH) LEVEL (P = 0.036), UN-MUTATED IMMUNOGLOBULIN HEAVY CHAIN VARIABLE REGION GENE (IGHV) (P = 0.004) AND THOSE WITH P53 ABERRATIONS (P < 0.001) HAD A MARKEDLY LOWER LEVELS OF NDRG2 MRNA. THIS DECREASE WAS ASSOCIATED WITH BRIEFER TIME-TO-TREATMENT (P = 0.001) AND POORER SURVIVAL (P < 0.001). HIGH EXPRESSION OF MIR-28-5P AND MIR-650 WAS ASSOCIATED WITH BINET B/C STAGE (P = 0.044) AND IGHV UN-MUTATED (P = 0.011), AS WELL AS BINET B/C STAGE (P = 0.013) AND P53 ABERRATIONS (P = 0.037), RESPECTIVELY. INHIBITION OF MIR-28-5P OR MIR-650 COULD INDUCE MORE APOPTOSIS IN CLL CELLS WITH GERMLINE TP53. CONCLUSIONS: NDRG2 MRNA LEVELS MIGHT BE A USEFUL PROGNOSTIC VARIABLE FOR PATIENTS OF CLL AND UP-REGULATING NDRG2 TRANSCRIPTION MAY BE A THERAPY APPROACH IN CLL WITHOUT P53 ABERRATIONS. 2018 14 2759 44 EXPRESSION OF IL-17 AND ITS GENE PROMOTER METHYLATION STATUS ARE ASSOCIATED WITH THE PROGRESSION OF CHRONIC HEPATITIS B VIRUS INFECTION. TO EXPLORE INTERLEUKIN-17 (IL-17) AND ITS EPIGENETIC REGULATION DURING THE PROGRESSION OF CHRONIC HEPATITIS B VIRUS (HBV) INFECTION.A TOTAL OF 162 PATIENTS WITH CHRONIC HBV INFECTION, INCLUDING 75 WITH CHRONIC HEPATITIS B (CHB), 54 WITH HEPATITIS B-ASSOCIATED LIVER CIRRHOSIS AND 33 WITH HEPATITIS B-ASSOCIATED HEPATOCELLULAR CARCINOMA (HBV-HCC), WERE ENROLLED IN THIS STUDY. THIRTY HEALTHY ADULTS OF THE SAME ETHNICITY WERE ENROLLED IN THE CONTROL GROUP. WHOLE VENOUS BLOOD WAS OBTAINED FROM THE PATIENTS AND NORMAL CONTROLS (N = 30). CLINICAL AND LABORATORY PARAMETERS WERE ASSESSED, AND WE PERFORMED ENZYME-LINKED IMMUNOSORBENT ASSAY AND QUANTITATIVE REAL-TIME PCR TO MEASURE THE SERUM LEVELS AND RELATIVE MRNA EXPRESSION OF IL-17, RESPECTIVELY. IL-17 PROMOTER METHYLATION IN PERIPHERAL BLOOD MONONUCLEAR CELLS WAS ASSESSED BY METHYLATION-SPECIFIC PCR. WE ANALYZED THE SERUM AND MRNA LEVELS OF IL-17 AND IL-17 PROMOTER METHYLATION IN THE 4 GROUPS AS WELL AS THE EFFECT OF METHYLATION ON SERUM IL-17 LEVELS. CORRELATIONS BETWEEN THE IL-17 PROMOTER METHYLATION STATUS AND CLINICAL PARAMETERS WERE ANALYZED BY SPEARMAN CORRELATION ANALYSIS.COMPARED TO THE NORMAL CONTROL GROUP, THE PATIENT GROUPS EXHIBITED SIGNIFICANTLY HIGHER SERUM AND RELATIVE MRNA LEVELS OF IL-17. THE METHYLATION DISTRIBUTION AMONG THE PATIENTS WAS SIGNIFICANTLY LOWER THAN THAT AMONG THE NORMAL CONTROLS (P < .05), WITH THE HBV-HCC GROUP SHOWING THE LOWEST IL-17 GENE METHYLATION FREQUENCY. THE AVERAGE IL-17 PROMOTER CG METHYLATION LEVEL WAS NEGATIVELY CORRELATED WITH IL-17 MRNA EXPRESSION (R = -0.39, P = .03), AND NEGATIVE CORRELATIONS BETWEEN IL-17 PROMOTER METHYLATION AND PROTHROMBIN TIME ACTIVITY (R = -0.585, P = .035), ALANINE AMINOTRANSFERASE (R = -0.522, P < .01), ASPARTATE AMINOTRANSFERASE (R = -0.315, P < .05), AND THE MODEL FOR END-STAGE LIVER DISEASE SCORE (R = -0.461, P < .05) WERE OBSERVED. IL-17 SERUM LEVELS IN THE METHYLATED-PROMOTER GROUPS WERE SIGNIFICANTLY LOWER THAN THOSE IN THE UNMETHYLATED-PROMOTER GROUPS.IL-17 EXPRESSION AND PROMOTER METHYLATION WERE ASSOCIATED WITH CHRONIC HBV INFECTION PROGRESSION, ESPECIALLY IN THE HBV-HCC GROUP. THE IL-17 PROMOTER STATUS MAY HELP CLINICIANS INITIATE THE CORRECT TREATMENT STRATEGY AT THE CHB STAGE. 2019 15 4245 45 METHYLATION STATUS OF DDIT3 GENE IN CHRONIC MYELOID LEUKEMIA. BACKGROUND: DNA-DAMAGE-INDUCIBLE TRANSCRIPT 3 (DDIT3), A CANDIDATE TUMOR SUPPRESSOR GENE (TSG), HAS BEEN FOUND INVOLVED IN THE REGULATION OF CELLULAR GROWTH AND DIFFERENTIATION. THE EPIGENETIC CHANGES OF TSGS ARE RECENTLY RECOGNIZED AS AN ABNORMAL MECHANISM CONTRIBUTING TO THE DEVELOPMENT OF CHRONIC MYELOID LEUKEMIA (CML). THE AIM OF THIS STUDY WAS TO INVESTIGATE THE METHYLATION STATUS OF DDIT3 GENE IN CML PATIENTS. METHODS: THE METHYLATION STATUS OF DDIT3 PROMOTER WAS DETECTED IN THE BONE MARROW MONONUCLEAR CELLS FROM 53 PATIENTS WITH CML USING METHYLATION-SPECIFIC PCR (MSP). THE EXPRESSION LEVELS OF DDIT3 AND BCR/ABL TRANSCRIPT WERE DETERMINED BY REAL-TIME QUANTITATIVE PCR (RQ-PCR). CLINICAL DATA OF THESE PATIENTS WERE COLLECTED AND ANALYZED. RESULTS: THE ABERRANT METHYLATION OF DDIT3 GENE PROMOTER WAS FOUND IN 35 OF 53 (66%) CML CASES. CORRELATION WAS NOT FOUND BETWEEN DDIT3 PROMOTER HYPERMETHYLATION AND THE AGE, SEX, HEMOGLOBIN CONCENTRATION, PLATELET COUNTS, CHROMOSOMAL ABNORMALITIES, BCR/ABL TRANSCRIPT, AND STAGING OF CML PATIENTS (P > 0.05), BUT FOUND BETWEEN DDIT3 PROMOTER HYPERMETHYLATION AND WBC COUNTS OF CML CASES (R = 0.781, P < 0.001). THE LEVEL OF DDIT3 TRANSCRIPT IN CML PATIENTS WAS SIGNIFICANTLY LOWER THAN THAT IN CONTROLS (MEDIAN 3.28 VS 19.69, P < 0.001), HOWEVER, THERE WAS NO DIFFERENCE IN THE LEVEL OF DDIT3 TRANSCRIPT BETWEEN METHYLATION-POSITIVE CML CASES (0.05-65.32, MEDIAN 2.13) AND METHYLATION- NEGATIVE CML CASES (0.12-126.04, MEDIAN 3.92) (P > 0.05). CONCLUSION: OUR RESULTS DEMONSTRATE THAT ABERRANT METHYLATION OF DDIT3 OCCURS IN CML FREQUENTLY. 2010 16 2031 31 EPIGENETIC CHANGES IN LYMPHOCYTES OF SOLVENT-EXPOSED INDIVIDUALS. AIM: WE INVESTIGATED GLOBAL DNA METHYLATION ALTERATIONS IN LYMPHOCYTES OF SOLVENT WORKERS AND CHRONIC TOXIC ENCEPHALOPATHY (CTE) PATIENTS AND EXPLORED POTENTIAL GENE-ENVIRONMENT INTERACTIONS FOR GST. POPULATION & METHODS: A CROSS-SECTIONAL STUDY WAS SET UP IN 41 REFERENTS, 128 SOLVENT WORKERS AND 23 CTE PATIENTS. RESULTS: WE FOUND A GLOBAL DNA HYPERMETHYLATION IN THE SOLVENT-EXPOSED POPULATION COMPARED WITH THE REFERENTS (P = 0.001, R = -0.544). GLOBAL DNA METHYLATION WAS NEGATIVELY ASSOCIATED WITH EXPOSURE. FURTHERMORE, GSTP1 GENOTYPIC POLYMORPHISM WAS FOUND TO BE SIGNIFICANTLY ASSOCIATED (P = 0.033) WITH GLOBAL DNA HYPOMETHYLATION, WHICH INDICATES A POTENTIAL ROLE FOR GENE-ENVIRONMENT INTERACTION IN THE ETIOLOGY OF SOLVENT-INDUCED NEUROBEHAVIORAL DISORDERS. CONCLUSION: THIS STUDY INDICATES THAT SOLVENT-INDUCED DNA METHYLATION ALTERATIONS HAVE AN IMPACT ON NEUROTOXICITY AND DEVELOPMENT OF CTE. 2012 17 1495 27 DNA HYPERMETHYLATION OF CELL CYCLE (P15 AND P16) AND APOPTOTIC (P14, P53, DAPK AND TMS1) GENES IN PERIPHERAL BLOOD OF LEUKEMIA PATIENTS. ABERRANT DNA METHYLATION OF TUMOR SUPPRESSOR GENES HAS BEEN REPORTED IN ALL MAJOR TYPES OF LEUKEMIA WITH POTENTIAL INVOLVEMENT IN THE INACTIVATION OF REGULATORY CELL CYCLE AND APOPTOSIS GENES. HOWEVER, MOST OF THE PREVIOUS REPORTS DID NOT SHOW THE EXTENT OF CONCURRENT METHYLATION OF MULTIPLE GENES IN THE FOUR LEUKEMIA TYPES. HERE, WE ANALYZED SIX KEY GENES (P14, P15, P16, P53, DAPK AND TMS1) FOR DNA METHYLATION USING METHYLATION SPECIFIC PCR TO ANALYZE PERIPHERAL BLOOD OF 78 LEUKEMIA PATIENTS (24 CML, 25 CLL, 12 AML, AND 17 ALL) AND 24 HEALTHY VOLUNTEERS. IN CML, METHYLATION WAS DETECTED FOR P15 (11%), P16 (9%), P53 (23%) AND DAPK (23%), IN CLL, P14 (25%), P15 (19%), P16 (12%), P53 (17%) AND DAPK (36%), IN AML, P14 (8%), P15 (45%), P53 (9%) AND DAPK (17%) AND IN ALL, P15 (14%), P16 (8%), AND P53 (8%). THIS STUDY HIGHLIGHTED AN ESSENTIAL ROLE OF DAPK METHYLATION IN CHRONIC LEUKEMIA IN CONTRAST TO P15 METHYLATION IN THE ACUTE CASES, WHEREAS TMS1 HYPERMETHYLATION WAS ABSENT IN ALL CASES. FURTHERMORE, HYPERMETHYLATION OF MULTIPLE GENES PER PATIENT WAS OBSERVED, WITH OBVIOUS SELECTIVENESS IN THE 9P21 CHROMOSOMAL REGION GENES (P14, P15 AND P16). INTERESTINGLY, METHYLATION OF P15 INCREASED THE RISK OF METHYLATION IN P53, AND VICE VERSA, BY FIVE FOLDS (P=0.03) INDICATING POSSIBLE SYNERGISTIC EPIGENETIC DISRUPTION OF DIFFERENT PHASES OF THE CELL CYCLE OR BETWEEN THE CELL CYCLE AND APOPTOSIS. THE INVESTIGATION OF MULTIPLE RELATIONSHIPS BETWEEN METHYLATED GENES MIGHT SHED LIGHT ON TUMOR SPECIFIC INACTIVATION OF THE CELL CYCLE AND APOPTOTIC PATHWAYS. 2014 18 1107 39 COMBINING CYTOGENETIC AND EPIGENETIC APPROACHES IN CHRONIC LYMPHOCYTIC LEUKEMIA IMPROVES PROGNOSIS PREDICTION FOR PATIENTS WITH ISOLATED 13Q DELETION. BACKGROUND: BOTH DEFECTIVE DNA METHYLATION AND ACTIVE DNA DEMETHYLATION PROCESSES ARE EMERGING AS IMPORTANT RISK FACTORS IN CHRONIC LYMPHOCYTIC LEUKEMIA (CLL). HOWEVER, ASSOCIATIONS BETWEEN 5-CYTOSINE EPIGENETIC MARKERS AND THE MOST FREQUENT CHROMOSOMAL ABNORMALITIES DETECTED IN CLL REMAIN TO BE ESTABLISHED. METHODS: CLL PATIENTS WERE RETROSPECTIVELY CLASSIFIED INTO A CYTOGENETIC LOW-RISK GROUP (ISOLATED 13Q DELETION), AN INTERMEDIATE-RISK GROUP (NORMAL KARYOTYPE OR TRISOMY 12), AND A HIGH-RISK GROUP (11Q DELETION, 17P DELETION, OR COMPLEX KARYOTYPE [>/= 3 BREAKPOINTS]). THE TWO 5-CYTOSINE DERIVATIVES, 5-METHYLCYTOSINE (5-MCYT) AND 5-HYDROXYMETHYLCYTOSINE (5-HMCYT), WERE TESTED BY ELISA (N = 60), WHILE REAL-TIME QUANTITATIVE PCR WAS USED FOR DETERMINING TRANSCRIPTIONAL EXPRESSION LEVELS OF DNMT AND TET (N = 24). RESULTS: BY USING GLOBAL DNA METHYLATION/DEMETHYLATION LEVELS, IN THE LOW-RISK DISEASE GROUP, TWO SUBGROUPS WITH SIGNIFICANTLY DIFFERENT CLINICAL OUTCOMES HAVE BEEN IDENTIFIED (MEDIAN TREATMENT-FREE SURVIVAL [TFS] 45 VERSUS > 120 MONTHS FOR 5-MCYT, P = 0.0008, AND 63 VERSUS > 120 MONTHS FOR 5-HMCYT, P = 0.04). A DEFECTIVE 5-MCYT STATUS WAS FURTHER ASSOCIATED WITH A HIGHER PERCENTAGE OF 13Q DELETED NUCLEI (> 80%), THUS SUGGESTING AN ACQUIRED PROCESS. WHEN CONSIDERING THE CYTOGENETIC INTERMEDIATE/HIGH-RISK DISEASE GROUPS, AN ASSOCIATION OF 5-MCYT STATUS WITH LYMPHOCYTOSIS (P = 0.0008) AND THE LYMPHOCYTE DOUBLING TIME (P = 0.04) BUT NOT WITH TFS WAS OBSERVED, AS WELL AS A REDUCTION OF DNMT3A, TET1, AND TET2 TRANSCRIPTS. CONCLUSIONS: COMBINING CYTOGENETIC STUDIES WITH 5-MCYT ASSESSMENT ADDS ACCURACY TO CLL PATIENTS' PROGNOSES AND PARTICULARLY FOR THOSE WITH 13Q DELETION AS A SOLE CYTOGENETIC ABNORMALITY. 2017 19 6898 19 [THE ADVANCE OF MODEL OF ACTION IN LOW-DOSE CHRONIC BENZENE EXPOSURE INDUCED HEMATOTOXICITY]. BENZENE IS CLASSIFIED AS GROUP 1 CARCINOGEN BY IARC. IT HAS BEEN FOUND THAT BENZENE INDUCES HEMATOTOXICITY EVEN IN LOW DOSE EXPOSURE. THE IDENTIFICATION OF KEY EVENTS DURING BENZENE INDUCED HEMATOTOXICTY LEADS TO ADJUSTMENT OF OCCUPATIONAL EXPOSURE LIMITS OF BENZENE. IN THIS REVIEW, WE FOCUS ON THE EXPOSURE, METABOLISM, TARGET ORGANS, KEY EPIGENETIC CHANGES, TOXICTY EFFECTS AND END POINTS OF LOW-DOSE CHRONIC BENZENE EXPOSURE INDUCED HEMATOTOXICITY AND FINALLY DISCUSS THE PERSPECTIVES ON THE FUTURE STUDY OF THIS AREA. 2015 20 3448 38 HYPERMETHYLATION OF THE N-MYC DOWNSTREAM-REGULATED GENE 2 PROMOTER IN PERIPHERAL BLOOD MONONUCLEAR CELLS IS ASSOCIATED WITH LIVER FIBROSIS IN CHRONIC HEPATITIS B. DNA METHYLATION IS A FUNDAMENTAL EPIGENETIC MODIFICATION TO REGULATE GENE EXPRESSION. N-MYC DOWNSTREAM-REGULATED GENE (NDRG) 2 IS A CYTOPLASMIC PROTEIN AND PARTICIPATES IN THE PATHOGENESIS OF LIVER FIBROSIS. IN THIS STUDY, THE MRNA EXPRESSION AND METHYLATION STATUS OF NDRG2 WAS EVALUATED IN PATIENTS WITH CHRONIC HEPATITIS B (CHB). THE STUDY INCLUDED 143 CHB PATIENTS AND 65 NORMAL CONTROLS (NC). THE MRNA EXPRESSION OF NDRG2 IN PERIPHERAL BLOOD MONONUCLEAR CELLS (PBMCS) WAS DETECTED BY QUANTITATIVE REAL-TIME POLYMERASE CHAIN REACTION. THE METHYLATION STATUS OF THE NDRG2 PROMOTER IN PBMCS WAS DETECTED BY METHYLATION-SPECIFIC POLYMERASE CHAIN REACTION. THE NDRG2 MRNA LEVEL WAS LOWER IN THE CHB GROUP THAN IN THE NC GROUP (P < 0.001). METHYLATION FREQUENCY OF THE NDRG2 PROMOTER WAS SIGNIFICANTLY HIGHER IN CHB PATIENTS THAN IN THE NC GROUP (52.44% VS. 26.15%, P < 0.001). IMPORTANTLY, THE RELATIVE EXPRESSION LEVELS OF NDRG2 MRNA WERE SIGNIFICANTLY LOWER IN THE METHYLATED GROUP THAN IN THE UNMETHYLATED GROUP IN BOTH CHB PATIENTS AND NC (P < 0.001). FURTHERMORE, A LOWER MRNA LEVEL AND HYPERMETHYLATION OF NDRG2 WERE ASSOCIATED WITH LIVER FIBROSIS AND INFLAMMATION GRADE IN CHB. THE ASPARTATE AMINOTRANSFERASE-TO-PLATELET RATIO INDEX (APRI) SCORE IS WIDELY USED TO PREDICT LIVER FIBROSIS. THE MRNA EXPRESSION LEVELS AND METHYLATION STATUS OF NDRG2 SHOWED A BETTER SCORE COMPARED TO APRI FOR DISCRIMINATING THE SEVERITY OF LIVER FIBROSIS. IN CONCLUSION, HYPERMETHYLATION OF NDRG2 IN PBMCS WAS CORRELATED WITH DECREASED MRNA EXPRESSION AND WITH LIVER FIBROSIS. THE METHYLATION STATUS OF THE NDRG2 PROMOTER IN PBMCS IS A POTENTIAL NONINVASIVE BIOMARKER TO PREDICT THE SEVERITY OF LIVER FIBROSIS. 2017