PIK3CB and nonpapillary renal cell carcinoma: Data from TCGA on a ccRCC study in 2013 demonstrated genetic alterations in components of each level of the PI3K/Akt signaling pathway cascade (PIK3CA, PIK3R1, PIK3R2, PTEN, PDPK1, AKT1, AKT2, AKT3, FOXO1, FOXO3, MTOR, RICTOR, TSC1, TSC2, RHEB, AKT1S1, and PRTOR), mainly including GNB2L1 amplification (6%), PI3KCA amplifications or mutations (5%), PTEN deletions or mutations (5%) or MTOR mutations (6%).