In the univariate Cox analysis, age (HR = 1.039, p <0.001), grade (HR = 1.391, p <0.001), stage (HR = 1.780, p <0.001) and CDC6 expression (HR = 1.266, p <0.001) were independent factors related to OS in ccRCC patients (Figure 4A). This evidence concerns the gene CDC6 and nonpapillary renal cell carcinoma.