The expression of EZH2 and G9a was considerably higher in breast cancer cells (MCF7, BT549, and MDA-MB-231) than in the noncancerous mammary epithelial cell (MCF10A), especially in the highly metastatic cells of the MDA-MB-231 cell line (Figure 1A,B, left). Here, EZH2 is linked to breast carcinoma.