title: Genotoxicity evaluation of individual cigarette smoke toxicants using the in vitro γH2AX assay by high content screening.
abstract: Cigarette smoke is a complex mixture consisting of more than 5600 identified chemical constituents of which approximately 150 have been identified so far as "tobacco smoke toxicants". Proposals made by the World Health Organisation Framework Convention on Tobacco Control mandate the lowering of nine tobacco smoke priority toxicants, including 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), N-nitrosonornicotine (NNN), and benzo[a]pyrene (B[a]P) and monitoring the levels of a further nine including cadmium. Here, we evaluated the genotoxic potential in human bronchial epithelial BEAS-2B cells of four cigarette smoke toxicants; NNK, NNN, B[a]P and cadmium using the novel in vitro γH2AX assay by High Content Screening (HCS). We also examined the genotoxicity of binary mixtures of NNK and NNN reporting their relative contribution to the genotoxic end-point. The results of this preliminary assessment showed that the in vitro γH2AX assay by HCS could be used as a pre-screening tool to detect and quantify the genotoxicity effect of cigarette smoke toxicants individually and in binary mixture. Moreover, the data produced could contribute to the prioritisation of toxicant reduction research in modified tobacco products.
authors.affiliation: British American Tobacco, Group Research and Development, Regents Park Road, Southampton, Hampshire SO15 8TL, United Kingdom; Department of Toxicology and Pharmacology, Universidad Complutense de Madrid, Madrid, Spain. Electronic address: Carolina_Garcia-Canton@bat.com.
authors.forename: Carolina
authors.initials: C
authors.lastname: Garcia-Canton
authors.forename: Arturo
authors.initials: A
authors.lastname: Anadon
authors.forename: Clive
authors.initials: C
authors.lastname: Meredith
mesh_terms: D001564:Benzo(a)pyrene / Q000633:toxicity*; D001980:Bronchi / Q000166:cytology / Q000187:drug effects; D002104:Cadmium / Q000633:toxicity*; D002460:Cell Line; D004847:Epithelial Cells / Q000187:drug effects; D006657:Histones; D006801:Humans; D009152:Mutagenicity Tests / Q000379:methods; D009602:Nitrosamines / Q000633:toxicity*; D012906:Smoke / Q000009:adverse effects / Q000032:analysis*; D062789:Tobacco Products
chemical_list: C468783:H2AX protein, human; D006657:Histones; D009602:Nitrosamines; D012906:Smoke; D002104:Cadmium; D001564:Benzo(a)pyrene; C016583:4-(N-methyl-N-nitrosamino)-1-(3-pyridyl)-1-butanone; C008655:N'-nitrosonornicotine
keywords: Cigarette smoke; Genotoxicity; In vitro; Tobacco regulation; γH2AX