Signaling inhibitors in metastatic renal cell carcinoma.

Renal cell carcinoma has made considerable progress in the past years, and new emerging strategies are coming almost every year since 2005. Development of targeted therapies in renal cell cancer is largely due to the fact that Von Hippel Lindau gene is often mutated in sporadic renal cell cancer. Von Hippel Lindau protein abnormalities lead to accumulation of hypoxia inducible factor-alpha, and activation of a series of gene, including vascular endothelial growth factor, and thus induce angiogenesis. Results from many recent studies with new agents, blocking the vascular endothelial growth factor pathway or the mammalian target of rapamycin pathway, have been recently reported and offer new strategic options for the patients with metastatic renal cell carcinoma. Sunitinib, sorafenib, and combination of bevacizumab and interferon improves progression free survival in either first or second line treatment of renal cell cancer and have been approved. Temsirolimus, a mammalian target of rapamycin inhibitor regulating hypoxia inducible factor-alpha, improves survival in renal cancer with poor risk features. Finally, everolimus improves progression free survival in patients who fail tyrosine kinase inhibitors. Overall, treatment of metastatic renal cell carcinoma is currently moving from the cytokine era to the targeted agent era. However, many questions still remain on the efficacy of combination treatments and on the best way to get complete remission, which is probably the best way to lead to cure of metastatic renal cell cancer in the future.