To further determine which cell cycle signaling pathway(s) are required for the proliferation and invasion of PRAD cells, we determined the expressions of Cyclin D1, CDK4, CDK6, p21 (Fig. S6), and p53 proteins of TOR1 AIP1 stably overexpressed cells by western blotting assays. The gene discussed is CDK4; the disease is prostate adenocarcinoma.