Knockdown of NF-kB1 by shRNA Inhibits the Growth of Renal Cell Carcinoma In Vitro and In Vivo

ABSTRACT

Renal cell carcinoma (RCC) accounts for approximately 2%-3% of human malignancies and is the most aggressive among urologic tumors. Biological heterogeneity, drug resistance, and chemotherapy side effects are the biggest obstacles to the effective treatment of RCC. The NF-kappa B transcription factor is one of several molecules identified to be responsible for the aggressive phenotype of this tumor. In the past decade, several studies have demonstrated the activation of NF-kappa B in RCC, and many have implicated NF-kappa B1 (p50) as an important molecule in tumor progression and metastasis. In the present study, a lentivirus was used to deliver shRNA targeting NF-kappa B1 into mouse RCC (Renca) cells. It was determined that the knockdown of the NF-kappa B1 gene led to a reduction in cell proliferation and late apoptosis/necrosis in vitro. Flow cytometry analysis demonstrated G(2)/M arrest in the cells. In addition, immunoblotting analysis revealed a significant increase in cyclin B1 and Bax. In vivo experiments showed that Renca-shRNA-NF-kappa B1 cells have significantly diminished tumori genicity. Moreover, immunohistochemical analysis revealed an increase in necrotic areas of Renca-shRNA-NF-kappa B1 tumors. Thus, this study indicates that downregulation of NF-kappa B1 can suppress RCC tumorigenesis by inducing late apoptosis/necrosis. Therefore, NF-kappa B1 may be a potential therapeutic target for RCC.