CCNA2 and posterior cortical atrophy: According to the fact that expression and activity of Skp2 is regulated by Cdk2 and cyclin A in PCa cells and that Skp2, Cdk2, and cyclin A coordinately regulate the cellular proliferation in PCa cells, we hypothesized that gene expression level of Skp2 (SKP2), Cdk2 (CDK2), and cyclin A (CCNA2) may show good positive correlation in PCa tumors.