CYP3A4 and prostate cancer: Although there is comparative histologic evidence of the decreased expression of CYP3A4 measured with staining immunoreactivity in prostate cancer subjects compared to 93% for benign epithelium, versus 75% of prostate tumors that express CYP3A4, there are many interindividual variations in CYP3A4 in the liver (>100-fold) and extra-hepatic tissues, depending on genetic factors [62].