RB1 and nonpapillary renal cell carcinoma: Mass-spectrometry-based proteomic data obtained from the National Cancer Institute’s Clinical Proteomic Tumor Analysis Consortium (CPTAC) [88, 89] confirmed that pRb protein abundance is higher in ccRCC primary tumors (n = 110) compared to normal tissue (n = 84) (Fig. 4A), with high pRb levels linked to reduced progression-free survival in ccRCC patients, indicating some prognostic value [90].