FGF1 and nonpapillary renal cell carcinoma: Given the result of our function module analysis which indicated that FGF1 gene involved PI3K-AKT signaling shall be in the core position of the DEGs PPI network, it’s of potential clinical value to further investigate the detailed function and the mechanism behind FGF1 related PI3K-AKT signaling pathways in the regulation of ccRCC development.