Univariate Cox proportional hazard analyses of the data for DFS showed that higher CK1ε expression is associated with an increase in DFS in BC patients with negative (wild type) p53 (HR = 0.32, 95% CI, 0.12 to 0.86, P = 0.018; Table 2), poor histologic differentiation (HR = 0.36, 95% CI, 0.13 to 0.98, P = 0.039), Ki67 ≥median (HR = 0.36, 95% CI, 0.13 to 1.03, P = 0.047), or a triple-negative subtype (HR = 0.42, 95% CI, 0.16 to 1.08, P = 0.018) (Figure 5). This evidence concerns the gene MKI67 and breast cancer.