Anti-proliferative actions of N0-desmethylsorafenib in human breast cancer cells
- Publication Type:
- Journal Article
- Biochemical Pharmacology, 2013, 86 (3), pp. 419 - 427
- Issue Date:
The multi-kinase inhibitor sorafenib is used for the treatment of renal and hepatic carcinomas and is undergoing evaluation for treatment of breast cancer in combination with other agents. Cytochrome P450 (CYP) 3A4 converts sorafenib to multiple metabolites that have been detected in patient plasma. However, recent clinical findings suggest that combination therapy may elicit inhibitory pharmacoki-netic interactions involving sorafenib that increase toxicity. While sorafenib N-oxide is an active metabolite, information on the anti-tumor actions of other metabolites is unavailable. The present study evaluated the actions of sorafenib and its five major metabolites in human breast cancer cell lines. All agents, with the exception of N0-hydroxymethylsorafenib N-oxide, decreased ATP formation in four breast cancer cell lines (MDA-MB-231, MDA-MB-468, MCF-7 and T-47D). Prolonged treatment of MDA-MB-231 cells with N0-desmethylsorafenib, N0-desmethylsorafenib N-oxide and sorafenib (10 mM, 72 h) produced small increases in caspase-3 activity to 128-139% of control. Sorafenib and its metabolites, again with the exception of N0-hydroxymethylsorafenib N-oxide, impaired MEK/ERK signaling in MDA-MB-231 cells and modulated the expression of cyclin D1 and myeloid cell leukemia sequence-1, which regulate cell viability. When coadministered with doxorubicin (0.5 or 1 mM), sorafenib and N0-desmethylsorafenib (25 mM) produced greater effects on ATP production than either treatment alone. Thus, it emerges that, by targeting the MEK/ERK pathway, multiple sorafenib metabolites may contribute to the actions of sorafenib in breast cancer. Because N0-desmethylsorafenib is not extensively metabolized and does not inhibit major hepatic CYPs, this metabolite may have a lower propensity to precipitate pharmacokinetic drug interactions than sorafenib. © 2013 Elsevier Inc. All rights reserved.
Please use this identifier to cite or link to this item: