CDK1 and breast cancer: The correlation analysis based on TCGA demonstrated that the expression of EZH2 was positively correlated with the expression of MKI67 (R = 0.64, P = 0, Figure 4F) and CDK1 (R = 0.51, P = 0, Figure 4G) and negatively correlated with the expression of CASP9 (R = −0.15, P = 1.5 × 10−6, Figure 4H) in BC.