1 6492 162 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 2 3441 37 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 3 228 44 ADAPTATION OF THE HUMAN POPULATION TO THE ENVIRONMENT: CURRENT KNOWLEDGE, CLUES FROM CZECH CYTOGENETIC AND "OMICS" BIOMONITORING STUDIES AND POSSIBLE MECHANISMS. THE HUMAN POPULATION IS CONTINUALLY EXPOSED TO NUMEROUS HARMFUL ENVIRONMENTAL STRESSORS, CAUSING NEGATIVE HEALTH EFFECTS AND/OR DEREGULATION OF BIOMARKER LEVELS. HOWEVER, STUDIES REPORTING NO OR EVEN POSITIVE IMPACTS OF SOME STRESSORS ON HUMANS ARE ALSO SOMETIMES PUBLISHED. THE MAIN AIM OF THIS REVIEW IS TO PROVIDE A COMPREHENSIVE OVERVIEW OF THE LAST DECADE OF CZECH BIOMONITORING RESEARCH, CONCERNING THE EFFECT OF VARIOUS LEVELS OF AIR POLLUTION (BENZO[A]PYRENE) AND RADIATION (URANIUM, X-RAY EXAMINATION AND NATURAL RADON BACKGROUND), ON THE DIFFERENTLY EXPOSED POPULATION GROUPS. BECAUSE SOME RESULTS OBTAINED FROM CYTOGENETIC STUDIES WERE OPPOSITE THAN HYPOTHESIZED, WE HAVE SEARCHED FOR A MEANINGFUL INTERPRETATION IN GENOMIC/EPIGENETIC STUDIES. A DETAILED ANALYSIS OF OUR DATA SUPPORTED BY THE STUDIES OF OTHERS AND CURRENT EPIGENETIC KNOWLEDGE, LEADS TO A HYPOTHESIS OF THE VERSATILE MECHANISM OF ADAPTATION TO ENVIRONMENTAL STRESSORS VIA DNA METHYLATION SETTINGS WHICH MAY EVEN ORIGINATE IN PRENATAL DEVELOPMENT, AND HELP TO REDUCE THE RESULTING DNA DAMAGE LEVELS. THIS HYPOTHESIS IS FULLY IN AGREEMENT WITH UNEXPECTED DATA FROM OUR STUDIES (E.G. LOWER LEVELS OF DNA DAMAGE IN SUBJECTS FROM HIGHLY POLLUTED REGIONS THAN IN CONTROLS OR IN SUBJECTS EXPOSED REPEATEDLY TO A POLLUTANT THAN IN THOSE WITHOUT PREVIOUS EXPOSURE), AND IS ALSO SUPPORTED BY DIFFERENCES IN DNA METHYLATION PATTERNS IN GROUPS FROM REGIONS WITH VARIOUS LEVELS OF POLLUTION. IN LIGHT OF THE ADAPTATION HYPOTHESIS, THE FOLLOWING POINTS MAY BE SUGGESTED FOR FUTURE RESEARCH: (I) THE CHRONIC AND ACUTE EXPOSURE OF STUDY SUBJECTS SHOULD BE DISTINGUISHED; (II) THE EXPOSURE HISTORY SHOULD BE MAPPED INCLUDING PLACE OF RESIDENCE DURING THE LIFE AND PRENATAL DEVELOPMENT; (III) CHANGES OF EPIGENETIC MARKERS SHOULD BE MONITORED OVER TIME. IN SUMMARY, INVESTIGATION OF HUMAN ADAPTATION TO THE ENVIRONMENT, ONE OF THE MOST IMPORTANT PROCESSES OF SURVIVAL, IS A NEW CHALLENGE FOR FUTURE RESEARCH IN THE FIELD OF HUMAN BIOMONITORING THAT MAY CHANGE OUR VIEW ON THE RESULTS OF BIOMARKER ANALYSES AND POTENTIAL NEGATIVE HEALTH IMPACTS OF THE ENVIRONMENT. 2017 4 5683 47 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