Several literature studies showed that miR-221/miR-222 are increased in prostate cancer and that they could increase S-phase kinase associated protein 2 (Skp2), cyclin A and cyclin D1 via targeting p27Kip1 suppression, leading to cell cycle progression at G1- to -S phase, increased clonogenicity in vitro and enhanced tumorigenicity in vivo [78–80]. Here, SKP2 is linked to prostate cancer.