More recently, we have shown that RTV blocked docetaxel-induced expression of cytochrome P450 3A4 (CYP3A4) and enhanced antitumour effects of docetaxel against DU145 human prostate cancer cells in vitro and in vivo (Ikezoe et al, 2004a). The gene discussed is CYP3A4; the disease is Familial prostate cancer.