CTLA4 and renal cell carcinoma: In addition to the VEGF pathway, the AKT/mTOR pathway has also been identified as a promising therapeutic target for the treatment of advanced RCC, and 2 mTOR inhibitors, everolimus and sirolimus, have received market approval.[46] Immune checkpoint (PD‐1/PD‐L1/CTLA4) inhibitors have recently emerged as effective treatments for advanced RCC that prevent tumor cell immune escape.