CTLA4 and clear cell renal carcinoma: In clear cell renal cell carcinoma (KIRC), a prognostic model based on KIF4A and related genes (UBE2C, OTX1, PPP2R2C) has shown that the risk score not only predicts patient outcomes but also positively correlates with the expression of immune checkpoints (e.g., PD-1, CTLA-4) and potential benefits from immunotherapy, indicating its utility in guiding treatment decisions for KIRC patients [119].