To predict the infiltration of immune cells in ccRCC by the TIMER algorithm, we assessed the correlations between the expression levels of the KGs and the levels of infiltration of six immune cells (CD8+ T cell, B cell, CD4+ T cell, dendritic cell, neutrophil, and macrophage) (S1 Fig in S1 File). This evidence concerns the gene CD4 and nonpapillary renal cell carcinoma.