title: Cellular determinants of oxaliplatin sensitivity in colon cancer cell lines.
abstract: Oxaliplatin (L-OHP) is a new platinum analogue that has shown antitumour activity against colon cancer both in vitro and in vivo and is now used in the chemotherapeutic treatment of metastatic colon and rectal cancer. L-OHP like cisplatin (CDDP), is detoxified by glutathione (GSH)-related enzymes and forms platinum (Pt)-DNA adducts lesions that are repaired by the nucleotide excision repair system (NER). We investigated the cytotoxicity and the pharmacology of L-OHP and CDDP on a panel of six colon cell lines in vitro. We showed that GSH and glutathione S-transferase (GST) activity were not correlated to oxaliplatin cytotoxicity. Pt-DNA adducts formation and repair were correlated with CDDP, but not with L-OHP cytotoxicity. The determination of ERCC1 and XPA expression, two enzymes of the NER pathway, by reverse transcriptase-polymerase chain reaction (RT-PCR), demonstrated that ERCC1 expression was predictive of L-OHP sensitivity (r(2)=0.67, P=0.02) and XPA level after oxaliplatin exposure was also correlated to L-OHP IC(50) (r(2)=0.5; P=0.04). The knowledge of such correlations could help predict the sensitivity of patients with colon cancer to L-OHP.
authors.affiliation: Groupe de Pharmacologie clinique et expérimentale (EA 3035), Institut Claudius Regaud, 20-24, rue du pont St Pierre, 31052 cedex, Toulouse, France.
authors.forename: S
authors.initials: S
authors.lastname: Arnould
authors.forename: I
authors.initials: I
authors.lastname: Hennebelle
authors.forename: P
authors.initials: P
authors.lastname: Canal
authors.forename: R
authors.initials: R
authors.lastname: Bugat
authors.forename: S
authors.initials: S
authors.lastname: Guichard
mesh_terms: D000970:Antineoplastic Agents / Q000627:therapeutic use*; D002945:Cisplatin / Q000627:therapeutic use*; D003110:Colonic Neoplasms / Q000188:drug therapy* / Q000201:enzymology; D018736:DNA Adducts / Q000378:metabolism; D004273:DNA, Neoplasm / Q000378:metabolism; D005978:Glutathione / Q000378:metabolism; D005982:Glutathione Transferase / Q000378:metabolism; D006801:Humans; D007928:Lethal Dose 50; D009944:Organoplatinum Compounds / Q000627:therapeutic use*; D000077150:Oxaliplatin; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods; D014407:Tumor Cells, Cultured / Q000187:drug effects
chemical_list: D000970:Antineoplastic Agents; D018736:DNA Adducts; D004273:DNA, Neoplasm; D009944:Organoplatinum Compounds; D012333:RNA, Messenger; D000077150:Oxaliplatin; D005982:Glutathione Transferase; D005978:Glutathione; D002945:Cisplatin