CYP3A4 and prostate cancer: To confirm this conclusion, castrated male nude mice were xenografted with the castrate resistant CWR-22RH human prostate cancer tissue and the animals immediately randomized into groups (n=10) which were: 1) left untreated as controls; 2) given daily oral treatment with tasquinimod alone via the drinking water (10mg/kg/day); 3) given oral ketoconazole alone via oral gavage at a daily dose which inhibits cytochrome P450 3A4 (i.e., 25 mg/kg/day) [32]; or 4) given a combination of the two drugs.