Methods and compositions are provided for treatment of cancer, including prostate cancer. In one aspect, the present invention provides a composition comprising a taxane and a drug that reduces efflux of the taxane from a cell. The drug that reduces efflux of the taxane can be an inhibitor of ABCB1 efflux activity. In some cases, the inhibitor of ABCB1 efflux activity is an inhibitor of ABCB1 ATPase activity selected from the group consisting of enzalutamide and bicalutamide.