MYC and breast carcinoma: Confirming our previous observation in mouse ES cells [20], MYC occupancy was observed at the proximal promoter of ZNF148 in both MCF7 (ER positive, luminal subtype) and MCF10A (normal-like) breast cancer cells (Fig. 1A), and this region harbored several canonical and non-canonical E-box sequences (Supplemental Fig. 1A).