E2F1 and breast cancer: To validate the molecular signature from the regulatory core in breast cancer, we used data from the TRANSBIG network (GEO id: GSE7390; n = 198) generated by Desmedt et al.22 Similar to bladder cancer patients, we observed that the progression-free survival probability of breast cancer patients was low for high expression of E2F1, EGFR, and TGFBR2 in different combinations (Fig. 7d–f).