title: Cytotoxicity determination without photochemical artifacts.
abstract: A study was performed to improve cytotoxicity determinations by eliminating flavin-mediated photosensitization from tests with KB cells, NCI-H69 cells, P-glycoprotein expressing KBC5-8 cells, MRP1-expressing H69AR cells, and A240286S human lung adenocarcinoma cells. Growth inhibition by cis-platin, doxorubicin, etoposide, gemcitabine, taxol, vincristine, vinblastine, and vinorelbine was determined under flavin-protecting conditions using flavin-free culture media with fetal bovine serum as the only source of flavins. As compared to conventional tests, the IC50 values determined under flavin-protecting conditions reflected increased apparent drug cytotoxicities, and were flawlessly reproducible. Flavin-mediated photosensitization should, therefore, be strictly eliminated from in vitro experiments involving cytotoxic and other drugs.
authors.affiliation: Abteilung Molekulare Toxikologie (E080), Deutsches Krebsforschungszentrum, Im Neuenheimer Feld 280, D-69120 Heidelberg, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Heuser
authors.forename: Marijana
authors.initials: M
authors.lastname: Kopun
authors.forename: Werner
authors.initials: W
authors.lastname: Rittgen
authors.forename: Christof
authors.initials: C
authors.lastname: Granzow
mesh_terms: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000032:analysis; D049109:Cell Proliferation / Q000187:drug effects; D018432:Drug Resistance, Multiple; D019008:Drug Resistance, Neoplasm; D004354:Drug Screening Assays, Antitumor / Q000379:methods*; D006801:Humans; D007624:KB Cells; D010777:Photochemistry; D012256:Riboflavin / Q000737:chemistry*; D059005:Topoisomerase II Inhibitors
chemical_list: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D059005:Topoisomerase II Inhibitors; D012256:Riboflavin