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  • DKFZ Publication Database  (34)
  • 1
    Keywords: MOUSE ; FUNCTIONAL GENOMICS ; DRUG ; genomic ; E ; BIOACTIVATION ; anticancer drug ; ellipticine ; genomics ; cytochrome P450 ; hepatic
    Type of Publication: Book chapter
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  • 2
    Keywords: CANCER ; CELLS ; EXPRESSION ; IN-VIVO ; LUNG-CANCER ; DNA adducts ; RISK ; GENE ; LINES ; ACTIVATION ; DNA ; 3-aminobenzanthrone ; 3-nitrobenzanthrone ; AIR ; CARCINOGENESIS ; CYP1A2 ; CYTO-TOXIC METABOLITES ; DIESEL EXHAUST ; DNA ADDUCT FORMATION ; ENVIRONMENTAL CONTAMINANT 3-NITROBENZANTHRONE ; GENETIC POLYMORPHISMS ; HETEROCYCLIC AMINES ; HETEROLOGOUS EXPRESSION ; HUMAN CYTOSOLIC SULFOTRANSFERASES ; IONS ; metabolic activation ; NAT : SULT ; nitro-PAH ; P-32- postlabeling ; PHENOL SULFOTRANSFERASES ; POSTLABELING ANALYSIS
    Abstract: 3-Nitrobenzanthrone (3-NBA) is a potent mutagen and suspected human carcinogen identified in diesel exhaust and ambient air pollution. 3-Aminobenzanthrone (3-ABA), 3- acetylaminobenzanthrone (3-Ac-ABA) and N-acetyl-N-hydroxy-3- aminobenzanthrone (N-Ac-N-OH-ABA) have been identified as 3-NBA metabolites. Recently we found that 3-NBA and its metabolites (3-ABA, 3-Ac-ABA and N-Ac-N-OH-ABA) form the same DNA adducts in vivo in rats. In order to investigate whether human cytochrome P450 (CYP) enzymes (i.e., CYPIA2), human N,O- acetyltransferases (NATs) and sulfotransferases (SULTs) contribute to the metabolic activation of 3-NBA and its metabolites we developed a panel of Chinese hamster V79MZ-hIA2 derived cell lines expressing human CYPIA2 in conjunction with human NATI, NAT2, SULTIAI or SULTIA2, respectively. Cells were treated with 0.01, 0.1 or I muM 3-NBA, or its metabolites (3- ABA, 3-Ac-ABA and N-Ac-N-OH-ABA). Using both enrichment versions of the P-32-postlabeling assay, nuclease P I digestion and butanol extraction, essentially 4 major and 2 minor DNA adducts were detected in the appropriate cell lines with all 4 compounds. The major ones were identical to those detected in rat tissue; the adducts lack an N-acetyl group. Human CYPIA2 was required for the metabolic activation of 3-ABA and 3-Ac-ABA (probably via N-oxidation) and enhanced the activity of 3-NBA (probably via nitroreduction). The lack of acetylated adducts suggests N-deacetylation of 3-Ac-ABA and N-Ac-N-OH-ABA. Thus, N-hydroxy-3-aminobenzanthrone (N-OH-ABA) appears to be a common intermediate for the formation of the electrophilic arylnitrenium ions capable of reacting with DNA. Human NAT I and NAT2 as well as human SULTIAI and SULTIA2 strongly contributed to the high genotoxicity of 3-NBA and its metabolites. Moreover, N,O-acetyltransfer reactions catalyzed by human NATs leading to the corresponding N-acetoxyester may be important in the bioactivation of N-Ac-N-OH-ABA. As human exposure to 3-NBA is likely to occur primarily via the respiratory tract, expression of CYPs, NATs and SULTs in respiratory tissues may contribute significantly and specifically to the metabolic activation of 3-NBA and its metabolites. Consequently, polymorphisms in these genes could be important determinants of lung cancer risk from 3-NBA
    Type of Publication: Journal article published
    PubMed ID: 12740904
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  • 3
    Keywords: BLOOD ; Germany ; LUNG ; DNA adducts ; EXPOSURE ; liver ; TISSUE ; HEART ; DNA ; kidney ; 3-nitrobenzanthrone ; DIESEL EXHAUST ; DNA ADDUCT FORMATION ; POSTLABELING ANALYSIS ; RAT ; BIOMARKERS ; CONTAMINANT 3-NITROBENZANTHRONE ; ENRICHMENT ; HPLC ; RATS ; METABOLITES ; HUMANS ; URINARY-BLADDER ; HUMAN ACETYLTRANSFERASES ; METABOLIC-ACTIVATION ; NUCLEOTIDES ; POLLUTANT 3-NITROBENZANTHRONE ; ADDUCTS ; PERFORMANCE LIQUID-CHROMATOGRAPHY ; DNA-ADDUCTS ; SURFACE SOIL ; V79 CELLS ; SINGLE ; RE ; EMISSIONS ; CARCINOGEN ; ADDUCT ; biomarker ; MUTAGEN 3-NITROBENZANTHRONE ; DNA ADDUCT ; intratracheal instillation ; P-32-postlabeling
    Abstract: 3-Nitrobenzanthrone (3-NBA) is an environmental pollutant and suspected human carcinogen found in emissions from diesel and gasoline engines and on the surface of ambient air particulate matter; human exposure to 3-NBA is likely to occur primarily via the respiratory tract. In our study female Sprague Dawley rats were treated by intratracheal instillation with a single dose of 0.2 or 2 mg/kg body weight of 3-NBA. Using the butanol enrichment version of the P-32-postlabeling method, DNA adduct formation by 3-NBA 48 hr after intratracheal administration in different organs (lung, pancreas, kidney, urinary bladder, heart, small intestine and liver) and in blood was investigated. The same adduct pattern consisting of up to 5 DNA adduct spots was detected by thin layer chromatography in all tissues and blood and at both doses. Highest total adduct levels were found in lung and pancreas (350 +/- 139 and 620 +/- 370 adducts per 10(8) nucleotides for the high dose and 39 +/- 18 and 55 +/- 34 adducts per 10(8) nucleotides for the low dose, respectively) followed by kidney, urinary bladder, heart, small intestine and liver. Adduct levels were dose-dependent in all organs (approximately 10-fold difference between doses). It was demonstrated by high performance liquid chromatography (HPLC) that all 5 3-NBA-derived DNA adducts formed in rats after intratracheal instillation are identical to those formed by other routes of application and are, as previously shown, formed from reductive metabolites bound to purine bases. Although total adduct levels in the blood were much lower (41 +/- 27 and 9.5 +/- 1.9 adducts per 10(8) nucleotides for the high and low dose, respectively) than those found in the lung, they were related to dose and to the levels found in lung. These results show that uptake of 3-NBA by the lung induces high levels of specific DNA adducts in several organs of the rat and an identical adduct pattern in DNA from blood. Therefore, 3-NBA-DNA adducts present in the blood are useful biomarkers for exposure to 3-NBA and may help to assess the effective biological dose in humans exposed to it. (C) 2005 Wiley-Liss, Inc
    Type of Publication: Journal article published
    PubMed ID: 15856450
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  • 4
    Keywords: SPECTRA ; CANCER ; CELLS ; CELL ; human ; DNA adducts ; EXPOSURE ; RISK ; GENE ; TISSUE ; PATIENT ; DNA ; MECHANISM ; CARCINOGENESIS ; DNA ADDUCT FORMATION ; RATS ; tumour ; ASSOCIATION ; ACID ; NUMBER ; MUTATION ; p53 ; MUTATIONS ; ADDUCTS ; INDIVIDUALS ; NEPHROPATHY ; mutagenesis ; CONSUMPTION ; aristolochic acid ; CHINESE HERBS NEPHROPATHY ; DNA-ADDUCTS ; RENAL-FAILURE ; molecular ; FEATURES ; ONCOLOGY ; MOLECULAR-MECHANISM ; RE ; PATTERN ; P53 GENE ; RAS GENE ; ADDUCT FORMATION ; development ; analysis ; DNA ADDUCT ; p53 mutation ; RISK-FACTOR ; SPECTRUM ; PREDICT ; aetiology ; COVALENT DNA ADDUCTION ; HUMAN P53 GENE ; OCHRATOXIN-A
    Abstract: Balkan endemic nephropathy (BEN) is found in certain rural areas of the Balkans and affects at least 25 000 inhabitants. Of the many hypotheses on BEN, the Aristolochia hypothesis has recently gained ground substantiated by the investigations on aristolochic acid nephropathy (AAN). On both clinical and morphological grounds, AAN is very similar to BEN. That exposure to aristolochic acid (AA) of individuals living in endemic areas through consumption of bread made with flour contaminated with seeds of Aristolochia clematitis is responsible for BEN is an old hypothesis, but one which is fully consistent with the unique epidemiologic features of BEN. Here, we propose an approach to investigate AA-induced mutagenesis in BEN that can provide molecular clues to the aetiology of its associated urothelial cancer. The molecular mechanism of AA-induced carcinogenesis demonstrates a strong association between DNA adduct formation, mutation pattern and tumour development. A clear link between urothelial tumours, p53 mutations and AA exposure should emerge as more tumour DNA from BEN patients from different endemic areas becomes available for mutation analysis. We predict that the observed p53 mutation spectrum will be dominated by AT -〉 TA transversion mutations as has already been demonstrated in the human p53 gene of immortalized cells after exposure to AAI and urothelial tumours from BEN patients in Croatia. Moreover, the detection of AA-specific DNA adducts in renal tissue of a number of BEN patients and individuals living in areas endemic for BEN in Croatia provides new evidence that chronic exposure to AA is a risk factor for BEN and its associated cancer
    Type of Publication: Journal article published
    PubMed ID: 17434925
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  • 5
    Keywords: EXPRESSION ; human ; liver ; ENZYMES ; PROTEIN ; TIME ; ACTIVATION ; DNA ; 3-aminobenzanthrone ; 3-nitrobenzanthrone ; DIESEL EXHAUST ; DNA ADDUCT FORMATION ; AIR-POLLUTION ; INDUCTION ; LIVER-MICROSOMES ; RAT ; SUDAN-I ; CONTAMINANT 3-NITROBENZANTHRONE ; RATS ; RAT-LIVER ; HUMAN ACETYLTRANSFERASES ; BODY ; air pollution ; INCREASE ; WEIGHT ; LEVEL ; ENZYME ; P-32-postlabeling ; reductive activation ; P-32-POSTLABELING ANALYSIS ; BIOTRANSFORMATION ENZYMES ; NAD(P)H-QUINONE OXIDOREDUCTASE ; NITROPOLYCYCLIC AROMATIC-HYDROCARBONS
    Abstract: 3-Nitrobenzanthrone (3-NBA), a suspected human carcinogen occurring in diesel exhaust and air pollution, and its human metabolite 3-aminobenzanthrone (3-ABA) were investigated for their ability to induce biotransformation enzymes in rat liver and the influence of such induction on DNA adduct formation by the compounds. Rats were treated (i.p.) with 0.4, 4, or 40 mg/kg body weight 3-NBA or 3-ABA. When hepatic cytosolic fractions from rats treated with 40 mg/kg body weight 3-NBA or 3-ABA were incubated with 3-NBA, DNA adduct formation, measured by P-32-postlabeling analysis, was 10-fold higher in incubations with cytosols from pretreated rats than with controls. The increase in 3-NBAderived DNA adduct formation corresponded to a dose-dependent increase in protein levels and enzymatic activity of NAD(P) H: quinone oxidoreductase (NQO1). NQO1 is the major enzyme reducing 3-NBA in human and rat livers. Incubations of 3-ABA with hepatic microsomes of rats treated with 3-NBA or 3-ABA (40 mg/ kg body weight) led to as much as a 12-fold increase in 3-ABA-derived DNA adduct formation compared with controls. The observed stimulation of DNA adduct formation by both compounds was attributed to their potential to induce protein expression and enzymatic activity of cytochromes P450 1A1 and/ or -1A2 (CYP1A1/2), the major enzymes responsible for 3-ABA activation in human and rat livers. Collectively, these results demonstrate for the first time, to our knowledge, that by inducing hepatic NQO1 and CYP1A1/2, both 3-NBA and 3-ABA increase the enzymatic activation of these two compounds to reactive DNA adduct-forming species, thereby enhancing their own genotoxic potential
    Type of Publication: Journal article published
    PubMed ID: 16714372
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  • 6
    Keywords: IN-VITRO ; human ; IN-VIVO ; LUNG ; MODEL ; VITRO ; DNA adducts ; liver ; ENZYMES ; METABOLISM ; MICE ; ACTIVATION ; DNA ; kidney ; DNA ADDUCT FORMATION ; LIVER-MICROSOMES ; RAT ; P-32-postlabelling ; BINDING ; MOUSE ; PATTERNS ; DNA-BINDING ; METABOLIC-ACTIVATION ; OXIDATION ; cytochrome P450 ; AGENT ; BODIES ; PATTERN ; WEIGHT ; LEVEL ; pharmacology ; USA ; LOSSES ; PROSTAGLANDIN-H SYNTHASE ; anticancer drug ; ellipticine ; ENVIRONMENTAL-POLLUTANT 3-NITROBENZANTHRONE ; peroxidase ; DETERMINES SUSCEPTIBILITY ; XENOBIOTIC-METABOLISM
    Abstract: Ellipticine is an antineoplastic agent, which forms covalent DNA adducts mediated by cytochromes P450 (CYP) and peroxidases. We evaluated the role of hepatic versus extra-hepatic metabolism of ellipticine, using the HRN (Hepatic Cytochrome P450 Reductase Null) mouse model, in which cytochrome P450 oxidoreductase (POR) is deleted in hepatocytes, resulting in the loss of essentially all hepatic CYP function. HRN and wild-type (WT) mice were treated i.p. with 1 and 10 mg/kg body weight of ellipticine. Multiple ellipticine-DNA adducts detected by P-32-postlabelling were observed in organs from both mouse strains. Highest total DNA binding levels were found in liver, followed by lung, kidney, urinary bladder, colon and spleen. Ellipticine-DNA adduct levels in the liver of HRN mice were up to 65% lower relative to WT mice, confirming the importance of CYP enzymes for the activation of ellipticine in livers, recently shown in vitro with human and rat hepatic microsomes. When hepatic microsomes of both mouse strains were incubated with ellipticine, ellipticine-DNA adduct levels with WT microsomes were up to 2.9-fold higher than with those from HRN mice. The ratios of ellipticine-DNA adducts in extra-hepatic organs between HRN and WT mice of up to 4.7 suggest that these organs can activate ellipticine and that more ellipticine is available in the circulation. These results and the DNA adduct patterns found in vitro and in vivo demonstrate that both CYP1A or 3A and peroxidases participate in activation of ellipticine to reactive species forming DNA adducts in the mouse model used in this study. (c) 2007 Elsevier Inc. All rights reserved
    Type of Publication: Journal article published
    PubMed ID: 17976674
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  • 7
    Keywords: CANCER ; BLOOD ; LUNG ; FOLLOW-UP ; lung cancer ; LUNG-CANCER ; DNA adducts ; EXPOSURE ; RISK ; SAMPLE ; SAMPLES ; DNA ; CARCINOGENESIS ; AIR-POLLUTION ; BIOMARKERS ; ASSOCIATION ; NO ; HUMANS ; DIFFERENCE ; REPAIR ; meta-analysis ; BLADDER ; bladder cancer ; BLADDER-CANCER ; cancer risk ; DAMAGE ; LYMPHOCYTES ; DNA-DAMAGE ; ADDUCTS ; CARCINOGENS ; case-control studies ; HEALTHY ; SMOKERS ; WHITE BLOOD-CELLS ; ALVEOLAR MACROPHAGES ; DNA-ADDUCTS ; ONCOLOGY ; case-control study ; INCREASE ; CARCINOGEN ; prospective studies ; LIFE ; METAANALYSIS ; LEVEL ; biomarker ; analysis ; DNA damage ; pooled analysis ; prospective ; prospective study ; ONSET ; COMPOUND ; CANCERS ; CANCER-RISK ; ENGLAND ; PREDICT ; POOLED-ANALYSIS ; HEAVY SMOKERS
    Abstract: Bulky DNA adducts are biomarkers of exposure to aromatic compounds and of the ability of the individual to metabolically activate carcinogens and to repair DNA damage. Their ability to predict cancer onset is uncertain. We have performed a pooled analysis of three prospective studies on cancer risk in which bulky DNA adducts have been measured in blood samples collected from healthy subjects (N = 1947; average follow-up 51-137 months). In addition, we have performed a meta-analysis by identifying all articles on the same subject published up to the end of 2006, including case-control studies. In the pooled analysis, a weakly statistically significant increase in the risk of lung cancer was apparent (14% per unit standard deviation change in adduct levels, 95% confidence interval 1-28%; using the weighted mean difference method, 0.15 SD, units higher adducts in cases than in controls). The association was evident only in current smokers and was absent in former smokers. Also the meta-analysis, which included both lung and bladder cancers, showed a statistically significant association in current smokers, whereas the results in never smokers were equivocal; in former smokers, no association was detected. The results of our pooled and meta-analyses suggest that bulky DNA adducts are associated with lung cancer arising in current smokers after a follow-up of several years
    Type of Publication: Journal article published
    PubMed ID: 18343884
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  • 8
    Keywords: 3-nitrobenzanthrone, 7,12-Dimethylbenz[a]anthracene, ADDUCTS, air pollution, Application, CANCER, CA
    Abstract: 3-Nitrobenzanthrone (3-NBA), a genotoxic mutagen found in diesel exhaust and ambient air pollution and its active metabolite N-hydroxy-3-aminobenzanthrone (N-OH-3-ABA) were tested for initiating and complete carcinogenic activity in the NMRI mouse skin carcinogenesis model. Both compounds were found to be inactive as either tumour initiators or complete carcinogens in mouse skin over a dose range of 25-400 nmol. Topical application of 3-NBA and N-OH-3-ABA produced DNA adduct patterns in epidermis, detected by P-32-postlabelling, similar to those found previously in other organs of rats and mice. 24 h after a single treatment of 100 nmol DNA adduct levels produced by 3-NBA (18 +/- 4 adducts/10(8) nucleotides) were 6 times lower than those by 7,12-dimethylbenz[a]anthracene (DMBA; 114 +/- 37 adducts/10(8) nucleotides). In contrast, identical treatment with N-OH-3-ABA resulted in adduct levels in the same range as with DMBA (136 +/- 25 adducts/10(8) nucleotides), indicating that initial DNA adduct levels do not parallel tumour initiating activity. When compounds were tested for tumour initiating activity by a single treatment followed by twice-weekly applications of TPA. DNA adducts formed by DMBA, but not by 3-NBA or N-OH-3-ABA, were still detectable 40 weeks after treatment. When tested for activity as complete carcinogens by twice-weekly topical application, 3-NBA and N-OH-3-ABA produced identical DNA adduct profiles in mouse skin, with adducts still detectable after 40 weeks. Only 3-NBA produced detectable adducts in other organs. (C) 2009 Elsevier Ireland Ltd. All rights reserved
    Type of Publication: Journal article published
    PubMed ID: 19442433
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  • 9
    Keywords: 3-aminobenzanthrone, 3-nitrobenzanthrone, ACTIVATION, ADDUCTS, animals, Benz(a)Anthracenes, biotrans
    Abstract: 3-aminobenzanthrone (3-ABA) is the metabolite of the carcinogenic air pollutant 3-nitrobenzanthrone (3-NBA). 3-ABA was investigated for its ability to induce cytochrome P450 1A1 (CYP1A1) and NAD(P)H:quinone oxidoreductase (NQO1) in kidney and lung of rats, and for the influence of such induction on DNA adduct formation by 3-ABA and 3-NBA. NQO1 is the enzyme that reduces 3-NBA to N-hydroxy-3-aminobenzanthrone (N-OH-3-ABA) and CYP1A enzymes oxidize 3-ABA to the same intermediate. When activated by cytosolic and and/or microsomal fractions isolated from rat lung, the target organ for 3-NBA carcinogenicity, and kidney, both compounds generated the same DNA-adduct pattern, consisting of five adducts. When pulmonary cytosols isolated from rats that had been treated i.p. with 40 mg/kg bw of 3-ABA were incubated with 3-NBA, DNA adduct formation was up to 1.7-fold higher than in incubations with cytosols from control animals. This increase corresponded to an increase in protein level and enzymatic activity of NQO1. In contrast, no induction of NQO1 expression by 3-ABA treatment was found in the kidney. Incubations of 3-ABA with renal and pulmonary microsomes of 3-ABA-treated rats led to an increase of up to a 4.5-fold in DNA-adduct formation relative to controls. The stimulation of DNA-adduct formation correlated with a higher protein expression and activity of CYP1A1 induced by 3-ABA. These results show that by inducing lung and kidney CYP1A1 and NQO1, 3-ABA increases its own enzymatic activation as well as that of the environmental pollutant, 3-NBA, thereby enhancing the genotoxic and carcinogenic potential of both compounds
    Type of Publication: Journal article published
    PubMed ID: 19398038
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  • 10
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