COXFA4L2 and nonpapillary renal cell carcinoma: NDUFA4L2 and its binding partners were involved in multiple types of ccRCC-related signaling pathways, such as the insulin-like growth factor 1 (IGF-1) signaling pathway, the mammalian target of Rapamycin (mTOR) signaling pathway, and the phosphoinositide 3 kinase serine/threonine protein kinase (PI3K/AKT) signaling pathway (Fig. 3D).