To study the mechanisms of the progression of hormone refractory prostate cancer, we established an AI prostate cancer cell line derived from AD LNCaP cells and demonstrated that Al cells are resistant to apoptosis and are deficient in expression of p21, which at least in part is due to the overexpressed AR (Gao et al, 1999; Wang et al, 2001). The gene discussed is AR; the disease is prostate carcinoma.