title: Genotoxic potential of selected cytostatic drugs in human and zebrafish cells.
abstract: Due to their increasing use, the residues of anti-neoplastic drugs have become emerging pollutants in aquatic environments. Most of them directly or indirectly interfere with the cell's genome, which classifies them into a group of particularly dangerous compounds. The aim of the present study was to conduct a comparative in vitro toxicological characterisation of three commonly used cytostatics with different mechanisms of action (5-fluorouracil [5-FU], cisplatin [CDDP] and etoposide [ET]) towards zebrafish liver (ZFL) cell line, human hepatoma (HepG2) cells and human peripheral blood lymphocytes (HPBLs). Cytotoxicity was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and acridine orange/ethidium bromide staining. All three drugs induced time- and dose-dependent decreases in cell viability. The sensitivity of ZFL and HepG2 cells towards the cytotoxicity of 5-FU was comparable (half maximal inhibitory concentration (IC50) 5.3 to 10.4 μg/mL). ZFL cells were more sensitive towards ET- (IC50 0.4 μg/mL) and HepG2 towards CDDP- (IC50 1.4 μg/mL) induced cytotoxicity. Genotoxicity was determined by comet assay and cytokinesis block micronucleus (CBMN) assay. ZFL cells were the most sensitive, and HPBLs were the least sensitive. In ZFL cells, induction of DNA strand breaks was a more sensitive genotoxicity endpoint than micronuclei (MNi) induction; the lowest effective concentration (LOEC) for DNA strand break induction was 0.001 μg/mL for ET, 0.01 μg/mL for 5-FU and 0.1 μg/mL for CDDP. In HepG2 cells, MNi induction was a more sensitive genotoxicity endpoint. The LOEC values were 0.01 μg/mL for ET, 0.1 μg/mL for 5-FU and 1 μg/mL for CDDP. The higher sensitivity of ZFL cells to cytostatic drugs raises the question of the impact of such compounds in aquatic ecosystem. Since little is known on the effect of such drugs on aquatic organisms, our results demonstrate that ZFL cells provide a relevant and sensitive tool to screen genotoxic potential of environmental pollutant in the frame of hazard assessment.
authors.affiliation: Mutagenesis Unit, Institute for Medical Research and Occupational Health, Ksaverska cesta 2, 10000, Zagreb, Croatia.
authors.forename: Goran
authors.initials: G
authors.lastname: Gajski
authors.affiliation: Mutagenesis Unit, Institute for Medical Research and Occupational Health, Ksaverska cesta 2, 10000, Zagreb, Croatia.
authors.forename: Marko
authors.initials: M
authors.lastname: Gerić
authors.affiliation: Department of Genetic Toxicology and Cancer Biology, National Institute of Biology, Večna pot 111, 1000, Ljubljana, Slovenia.
authors.forename: Bojana
authors.initials: B
authors.lastname: Žegura
authors.affiliation: Department of Genetic Toxicology and Cancer Biology, National Institute of Biology, Večna pot 111, 1000, Ljubljana, Slovenia.|Ecological Engineering Institute, Ljubljanska ulica 9, 2000, Maribor, Slovenia.
authors.forename: Matjaž
authors.initials: M
authors.lastname: Novak
authors.affiliation: Department of Genetic Toxicology and Cancer Biology, National Institute of Biology, Večna pot 111, 1000, Ljubljana, Slovenia.
authors.forename: Jana
authors.initials: J
authors.lastname: Nunić
authors.affiliation: Department of Genetic Toxicology and Cancer Biology, National Institute of Biology, Večna pot 111, 1000, Ljubljana, Slovenia.
authors.forename: Džejla
authors.initials: D
authors.lastname: Bajrektarević
authors.affiliation: Mutagenesis Unit, Institute for Medical Research and Occupational Health, Ksaverska cesta 2, 10000, Zagreb, Croatia.
authors.forename: Vera
authors.initials: V
authors.lastname: Garaj-Vrhovac
authors.affiliation: Department of Genetic Toxicology and Cancer Biology, National Institute of Biology, Večna pot 111, 1000, Ljubljana, Slovenia. metka.filipic@nib.si.
authors.forename: Metka
authors.initials: M
authors.lastname: Filipič
mesh_terms: D000165:Acridine Orange; D000818:Animals; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D002945:Cisplatin / Q000633:toxicity*; D054697:Cytostatic Agents / Q000633:toxicity*; D004996:Ethidium; D005047:Etoposide / Q000633:toxicity*; D005472:Fluorouracil / Q000633:toxicity*; D056945:Hep G2 Cells; D006801:Humans; D008214:Lymphocytes / Q000187:drug effects; D013778:Tetrazolium Salts; D013844:Thiazoles; D015027:Zebrafish
chemical_list: D054697:Cytostatic Agents; D013778:Tetrazolium Salts; D013844:Thiazoles; D005047:Etoposide; D004996:Ethidium; C022616:thiazolyl blue; D000165:Acridine Orange; D002945:Cisplatin; D005472:Fluorouracil
keywords: Cytostatic drugs; Environmental concentrations; Genotoxicity; HepG2 cells; Human lymphocytes; Zebrafish liver cells