title: Cellular response of X-ray sensitive hamster mutant cell lines to gemcitabine, cisplatin and 5-fluorouracil.
abstract: Five mutant Chinese hamster cell lines deficient in DNA repair with the corresponding parental cell lines were used to determine their sensitivity to cisplatin, 5-fluorouracil and gemcitabine. The mutations in the cell lines led to defective single strand break repair (EM-C11), defective recombination mediated repair (irs1SF), defective double strand break repair (XR-V15B, a Ku-80 mutant and CR-C1, a DNA-PKcs mutant) and an AT-like mutation (VC-4). All mutant cell lines had an impaired doubling time during exponential growth and an increased sensitivity to X-irradiation. We may conclude that for cisplatin-induced cytotoxicity the homologous recombination-associated DNA repair plays an important role in the repair of the cisplatin induced lesions, confirming previous results. In 5-FU and gemcitabine induced toxicity to cells, repair processes involved with radiation-induced damage were not implicated. This is in striking contrast to the role of cisplatin in radiosensitization where inhibition of the NHEJ pathway is implicated, and to the role of gemcitabine in sensitization where specific interference with the HR pathway is implicated.
authors.affiliation: Department of Radiotherapy, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands. j.haveman@amc.uva.nl
authors.forename: J
authors.initials: J
authors.lastname: Haveman
authors.forename: N
authors.initials: N
authors.lastname: Castro Kreder
authors.forename: H M
authors.initials: HM
authors.lastname: Rodermond
authors.forename: C
authors.initials: C
authors.lastname: van Bree
authors.forename: N A P
authors.initials: NA
authors.lastname: Franken
authors.forename: L J A
authors.initials: LJ
authors.lastname: Stalpers
authors.forename: M Z
authors.initials: MZ
authors.lastname: Zdzienicka
authors.forename: G J
authors.initials: GJ
authors.lastname: Peters
mesh_terms: D000818:Animals; D000964:Antimetabolites, Antineoplastic / Q000633:toxicity; D016466:CHO Cells; D002455:Cell Division / Q000187:drug effects / Q000528:radiation effects; D002460:Cell Line; D002945:Cisplatin / Q000633:toxicity*; D006224:Cricetinae; D004247:DNA / Q000235:genetics; D004260:DNA Repair / Q000187:drug effects* / Q000528:radiation effects*; D003841:Deoxycytidine / Q000031:analogs & derivatives* / Q000633:toxicity*; D004305:Dose-Response Relationship, Drug; D005472:Fluorouracil / Q000633:toxicity*; D014965:X-Rays; D000093542:Gemcitabine
chemical_list: D000964:Antimetabolites, Antineoplastic; D003841:Deoxycytidine; D004247:DNA; D002945:Cisplatin; D005472:Fluorouracil; D000093542:Gemcitabine