Immune Escape Mechanisms of Renal Cell Carcinoma

Renal cell carcinoma (RCC) represents a chemotherapy- and radiation-resistant tumor with a generally poor prognosis and a 5-yr survival rate of patients of <10%. Although immunotherapy is an alternative intervention leading to clinical responses in a subset of patients with RCC, this tumor has developed different strategies to escape from immunosurveillance. This could be due to alterations in the tumor itself resulting in its impaired recognition by the immune system, by the tumor microenvironment, and by the dysfunction of immune cells of patients with RCC. This review summarizes the diverse immune escape mechanisms of RCC and discusses current and future strategies to circumvent these defects. This knowledge together with the identification of novel, more universal antigens will contribute to an improved design of RCC-specific immunotherapies.