Inactivation of transforming growth factor-β-activated kinase 1 promotes taxol efficacy in ovarian cancer cells.

Resistance to taxol represents a major obstacle for long-term remission in ovarian cancer. Transforming Growth Factor-β-Activated Kinase 1 (TAK1) is a critical component in immune response pathway. However, the role of TAK1 in the development of chemoresistance in ovarian cancer remains unknown. Here, we showed that in vitro, taxol-resistant cells expressed higher TAK1, and the ratio of p-TAK1/TAK1 positively associated with taxol resistance in ovarian cancer cells. Inactivation of TAK1 by inhibitor 5Z-7-oxozeaenol or gene knockdown sensitized taxol cytotoxicity in vitro, promoting cell apoptosis and mitosis arrest. Moreover, resistant cells were much more sensitive to the combined TAK1 inhibitor and taxol treatment than their parental counterparts. Using xenograft mouse model, we found that 5Z-7-oxozeaenol significantly enhanced taxol efficacy in vivo. Thus, targeting TAK1 pathway is a promising strategy to enhance taxol response in ovarian cancer treatment.