title: Characterization of a clonal isolate of an oxaliplatin resistant ovarian carcinoma cell line A2780/C10.
abstract: A single cell clonal sub-line A2780/C10B that is 18-fold resistant to oxaliplatin and approximately threefold cross-resistant to cisplatin and exhibiting a metastasis associated cellular phenotype was characterized for mechanisms of resistance. The cell line exhibited a 50% reduction in the accumulation of both oxaliplatin and cisplatin relative to the parent line, while extensive decline in Pt-DNA adduct levels occurred only following oxaliplatin treatment. The basal GSH levels were fivefold higher in A2780/C10B compared to A2780 and had a fivefold elevation in gamma-GT suggesting this may be the mechanism involved in GSH elevation. The basal levels of ERCC-1, XPA and MRP-2 mRNA levels in A2780/C10B were not higher than those in A2780. The highly reduced Pt-DNA adduct formation only for oxaliplatin, but not cisplatin may be a reflection of the fact that at equimolar concentrations oxaliplatin makes fewer Pt-DNA adducts than cisplatin. The data indicate that multiple lesions occur in a single cell to produce the resistant phenotype.
authors.affiliation: Department of Medicine, Roswell Park Cancer Institute, Elm and Carlton Streets, Buffalo, NY 14263, USA.
authors.forename: Suzanne
authors.initials: S
authors.lastname: Hector
authors.forename: Maria Enriqueta
authors.initials: ME
authors.lastname: Nava
authors.forename: Kimberly
authors.initials: K
authors.lastname: Clark
authors.forename: Michael
authors.initials: M
authors.lastname: Murphy
authors.forename: Lakshmi
authors.initials: L
authors.lastname: Pendyala
mesh_terms: D000970:Antineoplastic Agents / Q000378:metabolism / Q000494:pharmacology; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D002945:Cisplatin / Q000378:metabolism / Q000494:pharmacology; D002999:Clone Cells / Q000187:drug effects / Q000378:metabolism; D018736:DNA Adducts / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics; D004305:Dose-Response Relationship, Drug; D018432:Drug Resistance, Multiple; D019008:Drug Resistance, Neoplasm; D004720:Endonucleases / Q000235:genetics; D005260:Female; D005721:Glutamate-Cysteine Ligase / Q000235:genetics / Q000378:metabolism; D005978:Glutathione / Q000378:metabolism; D006801:Humans; D026901:Membrane Transport Proteins / Q000235:genetics; D000089762:Multidrug Resistance-Associated Protein 2; D027425:ATP-Binding Cassette, Sub-Family C Proteins / Q000235:genetics; D009944:Organoplatinum Compounds / Q000378:metabolism / Q000494:pharmacology*; D010051:Ovarian Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D000077150:Oxaliplatin; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D051760:Xeroderma Pigmentosum Group A Protein / Q000235:genetics; D005723:gamma-Glutamyltransferase / Q000235:genetics / Q000378:metabolism
chemical_list: D000970:Antineoplastic Agents; D002945:Cisplatin; D018736:DNA Adducts; D004268:DNA-Binding Proteins; D004720:Endonucleases; D005721:Glutamate-Cysteine Ligase; D005978:Glutathione; D026901:Membrane Transport Proteins; D000089762:Multidrug Resistance-Associated Protein 2; D027425:ATP-Binding Cassette, Sub-Family C Proteins; D009944:Organoplatinum Compounds; D000077150:Oxaliplatin; D012333:RNA, Messenger; D051760:Xeroderma Pigmentosum Group A Protein; D005723:gamma-Glutamyltransferase; C000715087:ABCC2 protein, human; C497314:XPA protein, human; C071447:ERCC1 protein, human