Other agents that induce G1 arrest of prostate carcinoma lines, such as 12-O-tetra-decanoylphorbol-13-acetate, indole-3-carbinol and inositol hexaphosphate, also upregulate p21waf1 and p27Kip1, leading to decreases in cyclin-dependent kinase activities (Chinni et al, 2001; Sugibayashi et al, 2002; Singh et al, 2003). The gene discussed is CDKN1B; the disease is prostate carcinoma.