In the combined cohort as described previously16, patients whose breast cancer expressed a low level of Cdc6 had a significantly longer survival than those patients whose tumors expressed Cdc6 at a high level (Wilcoxon-Gehan test, p < 0.001; Univariate Cox regression, hazard ratio = 1.409, 95% confidence interval = 1.192–1.666, p < 0.001; Fig. 3A). Here, CDC6 is linked to breast cancer.