title: The effect of benzo(a)pyrene on porcine urinary bladder epithelial cells analyzed for the expression of selected genes and cellular toxicological endpoints.
abstract: Consumption of tobacco products is the most relevant risk factor for the development of bladder cancer beside occupational contributions. In order to investigate mechanisms of tobacco smoke components in bladder carcinogenesis we have introduced a primary epithelial cell culture system derived from porcine urinary bladder as a suitable representative for the corresponding human tissue under physiological conditions. Two independent readouts were selected as markers for genotoxic events. Changes in the expression level of several toxicologically relevant genes should serve as indicators for early response, while classical genotoxic endpoints monitored manifested damages. Here, we present the first results of our study with benzo(a)pyrene (BaP) as a member of polycyclic aromatic hydrocarbons (PAHs) found in tobacco smoke. Cells treated with BaP show a dramatic increase in the expression of CYP1A1 that appears to be both indicator of and contributor for BaP toxicity. Genes coding for other proteins relevant in xenobiotic metabolism, signal transduction or tumor suppression show moderate effects or no enhancement of their expression levels. Comet assay and micronucleus test did show a significant, dose-dependent increase in DNA damages or aberrations after cell division. While these effects are conforming to the response at the mRNA expression level, they are less pronounced and require rather higher dosages of the chemical.
authors.affiliation: Max-Planck-Institut für Molekulare Physiologie, Abteilung Strukturelle Biologie, Otto-Hahn-Strasse 11, 44227 Dortmund, Germany.
authors.forename: Alexander
authors.initials: A
authors.lastname: Wolf
authors.forename: Alexandra
authors.initials: A
authors.lastname: Kutz
authors.forename: Sabine
authors.initials: S
authors.lastname: Plöttner
authors.forename: Claudia
authors.initials: C
authors.lastname: Behm
authors.forename: Herrmann M
authors.initials: HM
authors.lastname: Bolt
authors.forename: Wolfram
authors.initials: W
authors.lastname: Föllmann
authors.forename: Jürgen
authors.initials: J
authors.lastname: Kuhlmann
mesh_terms: D000393:Air Pollutants / Q000633:toxicity*; D000818:Animals; D001564:Benzo(a)pyrene / Q000633:toxicity*; D002273:Carcinogens / Q000633:toxicity*; D002478:Cells, Cultured; D020552:Comet Assay; D019363:Cytochrome P-450 CYP1A1 / Q000096:biosynthesis* / Q000235:genetics; D004249:DNA Damage; D004305:Dose-Response Relationship, Drug; D004847:Epithelial Cells / Q000187:drug effects* / Q000201:enzymology; D015971:Gene Expression Regulation, Enzymologic; D015162:Micronucleus Tests; D012907:Smoking; D013552:Swine; D001743:Urinary Bladder / Q000187:drug effects* / Q000201:enzymology
chemical_list: D000393:Air Pollutants; D002273:Carcinogens; D001564:Benzo(a)pyrene; D019363:Cytochrome P-450 CYP1A1