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Epidemiological and laboratory studies have shown significant associations between PAH exposure and subsequent development of cancer in various organs. Molecular dosimetry of DNA adduct formation typically involves tissue DNA extraction followed by DNA adduct analysis using techniques incapable of observing specific cells within a complex tissue. Here we report localization and semi-quantitation of PAH-DNA adducts in paraffin-embedded sections of human cervix, vulva, placenta and prostate utilizing IHC with an antibody generated against DNA modified with (+/-)-7β,8α-dihydroxy-9α,10α-epoxy-7,8,9,10-tetrahydrobenzo[a]pyrene (BPDE). Serial sections were stained with hematoxylin (to identify nuclei), specific anti-BPDE-DNA antiserum (to visualize adducts) or immunogen-absorbed anti-BPDE-DNA serum (for background). Semi-quantitation was achieved by comparison of test sample nuclear color intensity with a standard curve of human keratinocytes exposed to increasing concentrations of BPDE and analyzed for BPDE-DNA adducts by both IHC/ACIS and quantitative BPDE-DNA immunoassay. A survey of cervix from 75 individuals, placenta from 14 individuals, vulva from 19 individuals and prostate from 5 individuals has revealed large inter-individual variability in PAH-DNA adduct levels in these reproductive organ tissues. The highest concentrations of PAH-DNA adducts were observed in the basal epithelial cells of human cervix and vulva, in the cytotrophoblast cells lining the chorionic villi of the placenta and in the endothelial cells lining the ducts of the prostate. Comparison with the standard curve revealed PAH-DNA adduct concentrations ranging from ∼12 (limit of detection) to approximately 190 adducts/108 nucleotides. The study shows that many if not most individuals have PAH-DNA adducts in cervical, vulvar and prostate tissue that could reflect short- or long-term PAH exposures, while the placental PAH-DNA adducts clearly represent short-term exposures. The non-destructive DNA a

Epidemiological and laboratory studies have shown significant associations between PAH exposure and subsequent development of cancer in various organs. Molecular dosimetry of DNA adduct formation typically involves tissue DNA extraction followed by DNA adduct analysis using techniques incapable of observing specific cells within a complex tissue. Here we report localization and semi-quantitation of PAH-DNA adducts in paraffin-embedded sections of human cervix, vulva, placenta and prostate utilizing IHC with an antibody generated against DNA modified with (+/-)-7β,8α-dihydroxy-9α,10α-epoxy-7,8,9,10-tetrahydrobenzo[a]pyrene (BPDE). Serial sections were stained with hematoxylin (to identify nuclei), specific anti-BPDE-DNA antiserum (to visualize adducts) or immunogen-absorbed anti-BPDE-DNA serum (for background). Semi-quantitation was achieved by comparison of test sample nuclear color intensity with a standard curve of human keratinocytes exposed to increasing concentrations of BPDE and analyzed for BPDE-DNA adducts by both IHC/ACIS and quantitative BPDE-DNA immunoassay. A survey of cervix from 75 individuals, placenta from 14 individuals, vulva from 19 individuals and prostate from 5 individuals has revealed large inter-individual variability in PAH-DNA adduct levels in these reproductive organ tissues. The highest concentrations of PAH-DNA adducts were observed in the basal epithelial cells of human cervix and vulva, in the cytotrophoblast cells lining the chorionic villi of the placenta and in the endothelial cells lining the ducts of the prostate. Comparison with the standard curve revealed PAH-DNA adduct concentrations ranging from ∼12 (limit of detection) to approximately 190 adducts/108 nucleotides. The study shows that many if not most individuals have PAH-DNA adducts in cervical, vulvar and prostate tissue that could reflect short- or long-term PAH exposures, while the placental PAH-DNA adducts clearly represent short-term exposures. The non-destructive DNA a

Udgivelsesdato: 2006-Aug-30, The Teplice area in the Czech Republic is a mining district where elevated levels of air pollution including airborne carcinogens, have been demonstrated, especially during winter time. This environmental exposure can impact human health; in particular children may be more vulnerable. To study the impact of air pollution in children at the transcriptional level, peripheral blood cells were subjected to whole genome response analysis, in order to identify significantly modulated biological pathways and processes as a result of exposure. Using genome-wide oligonucleotide microarrays, we investigated differential gene expression in children from the Teplice area (n=23) and compared them with children from the rural control area of Prachatice (n=24). In an additional approach, individual gene expressions were correlated with individual peripheral blood lymphocyte micronuclei frequencies, in order to evaluate the linkage of individual gene expressions with an established biomarker of effect that is representative for increased genotoxic risk. Children from the Teplice area showed a significantly higher average micronuclei frequency than Prachatice children (p=0.023). For considerable numbers of genes, the expression differed significantly between the children from the two areas. Amongst these genes, considerable numbers of genes were observed to correlate significantly with the frequencies of micronuclei. The main biological process that appeared significantly affected overall was nucleosome assembly. This suggests an effect of air pollution on the primary structural unit of the condensed DNA. In addition, several other pathways were modulated. Based on the results of this study, we suggest that transcriptomic analysis represents a promising biomarker for environmental carcinogenesis.

Udgivelsesdato: 2006-Aug-30, The Teplice area in the Czech Republic is a mining district where elevated levels of air pollution including airborne carcinogens, have been demonstrated, especially during winter time. This environmental exposure can impact human health; in particular children may be more vulnerable. To study the impact of air pollution in children at the transcriptional level, peripheral blood cells were subjected to whole genome response analysis, in order to identify significantly modulated biological pathways and processes as a result of exposure. Using genome-wide oligonucleotide microarrays, we investigated differential gene expression in children from the Teplice area (n=23) and compared them with children from the rural control area of Prachatice (n=24). In an additional approach, individual gene expressions were correlated with individual peripheral blood lymphocyte micronuclei frequencies, in order to evaluate the linkage of individual gene expressions with an established biomarker of effect that is representative for increased genotoxic risk. Children from the Teplice area showed a significantly higher average micronuclei frequency than Prachatice children (p=0.023). For considerable numbers of genes, the expression differed significantly between the children from the two areas. Amongst these genes, considerable numbers of genes were observed to correlate significantly with the frequencies of micronuclei. The main biological process that appeared significantly affected overall was nucleosome assembly. This suggests an effect of air pollution on the primary structural unit of the condensed DNA. In addition, several other pathways were modulated. Based on the results of this study, we suggest that transcriptomic analysis represents a promising biomarker for environmental carcinogenesis.

Udgivelsesdato: 2006-Aug-30, The Teplice area in the Czech Republic is a mining district where elevated levels of air pollution including airborne carcinogens, have been demonstrated, especially during winter time. This environmental exposure can impact human health; in particular children may be more vulnerable. To study the impact of air pollution in children at the transcriptional level, peripheral blood cells were subjected to whole genome response analysis, in order to identify significantly modulated biological pathways and processes as a result of exposure. Using genome-wide oligonucleotide microarrays, we investigated differential gene expression in children from the Teplice area (n=23) and compared them with children from the rural control area of Prachatice (n=24). In an additional approach, individual gene expressions were correlated with individual peripheral blood lymphocyte micronuclei frequencies, in order to evaluate the linkage of individual gene expressions with an established biomarker of effect that is representative for increased genotoxic risk. Children from the Teplice area showed a significantly higher average micronuclei frequency than Prachatice children (p=0.023). For considerable numbers of genes, the expression differed significantly between the children from the two areas. Amongst these genes, considerable numbers of genes were observed to correlate significantly with the frequencies of micronuclei. The main biological process that appeared significantly affected overall was nucleosome assembly. This suggests an effect of air pollution on the primary structural unit of the condensed DNA. In addition, several other pathways were modulated. Based on the results of this study, we suggest that transcriptomic analysis represents a promising biomarker for environmental carcinogenesis.

Acrylonitrile (AN) is an important intermediary for the synthesis of a variety of organic products, such as artificial fibres, household articles and resins. Although acute effects are the primary concern for an exposure to AN, potential genotoxic, carcinogenic and teratogenic risks of AN have to be taken seriously in view of the large number of workers employed in such industries and the world-wide population using products containing and possibly liberating AN. An understanding of the effect of acrylonitrile must be based on a characterization of its metabolism as well as of the resulting products and their genotoxic properties. Tests for mutagenicity in bacteria have in general been positive, those in plants and on unscheduled DNA synthesis doubtful, and those on chromosome aberrations in vivo negative. Wherever positive results had been obtained, metabolic activation of AN appeared to be a prerequisite. The extent to which such mutagenic effects are significant in man depends, however, also on the conditions of exposure. It appears from the limited data that the ultimate mutagenic factor(s), such as 2-cyanoethylene oxide, may have little opportunity to act under conditions where people are exposed because it is formed only in small amounts and is rapidly degraded. The carcinogenic action of AN has been evaluated by various agencies and ranged from 'reasonably be anticipated to be a human carcinogen' to 'cannot be excluded', the most recent evaluation being 'possibly carcinogenic to humans'. Animal data that confirm the carcinogenic potential of AN have certain limitations with respect to the choice of species, type of tumors and length of follow up. Epidemiological studies which sometimes, but not always, yielded positive results, encounter the usual difficulties of confounding factors in chemical industries. Exposure of workers to AN should continue to be carefully monitored, but AN would not have to be considered a cancer risk to the population provided limita