Although mounting evidence suggests that EZH2 was aberrantly elevated in a subset of aggressive solid tumors including breast cancer [43], melanoma [44], bladder cancer [45], gastric cancer [46] and other cancers [47], recent studies in myeloid malignancies and lymphomas show that EZH2 has a tumor suppressor role [48], suggesting that the role of EZH2 in cancer development varies with different types of cancer [49]. This evidence concerns the gene EZH2 and breast cancer.