Interference of Skp2 effectively inhibits the development and metastasis of colon carcinoma

Colon cancer is a common type of malignancy in the digestive system. The aim of the present study was to investigate the role of S-phase kinase-associated protein 2 (Skp2) in colon carcinoma and to identify whether depletion of Skp2 by Skp2-RNA interference (RNAi) attenuates the proliferation and migration of colon carcinoma. Three pairs of small interfering (si)RNA were designed based on the Skp2 gene sequence and the most effective one was used to silence the Skp2 gene in SW620 cells. Subsequent to the interference, quantitative polymerase chain reaction and western blot analysis were used for detecting the expression of Skp-2 mRNA and protein, respectively. The data demonstrated that the Skp2-siRNA effectively inhibited proliferation (P<0.01), increased the levels of apoptosis and induced G(0)/G(1) phase arrest of the SW620 cells (P<0.01). Transfection of the Skp2 siRNA into SW620 cells effectively reduced Skp2 protein levels, while p27 protein levels increased, In the in vivo experiments, a lentiviral vector of the Skp2-RNAi transfected into SW620 cells markedly inhibited Skp2 expression, as detected by immunohistochemical analysis of nude mice. Additionally, tumorigenicity experiments showed that inhibition of Skp2 significantly increased the survival rate of nude mice. Thus, the in vitro and in vivo results demonstrated that interference of Skp2 expression significantly inhibited the proliferation and induced the apoptosis of SW620 cells. This suggests that Skp2 protein has an important role in the progression of colon cancer. Therefore, Skp2 may enable the early diagnosis of colon cancer and provide new insights into molecular targets for cancer therapy.