[OA] [Mice] testosterone Diminishes Cabazitaxel Efficacy and Intratumoral Accumulation in a Prostate Cancer Xenograft Model http://www.ebiomedicine.com/article/S2352-3964(17)30505-4/fulltext Highlights • Cabazitaxel is highly effective in a castrate setting, while tumor growth inhibition is completely abolished with high AR pathway activity. • Intratumoral cabazitaxel levels were 3.5 times higher in tumors from castrated mice as compared to tumors from androgen-supplemented animals. We studied the efficacy of the chemotherapeutic cabazitaxel in castrate mice and mice receiving testosterone. While cabazitaxel was highly effective in castrate mice, it was ineffective in mice receiving testosterone. This was likely caused by higher cabazitaxel levels, as chemotherapeutic levels in tumors from castrate mice were about 3.5 fold higher. Our study shows that cabazitaxel efficacy might be impacted by androgens and cabazitaxel efficacy is improved in combination with androgen deprivation therapy and possibly androgen receptor targeted therapy.