SETDB1 and breast cancer: Among the eight most frequently amplified HMTs (totaling more than 5% of 958 samples), the frequencies of ASH1L, SETDB1, and SMYD3 amplification were dramatically higher in basal-like breast cancer, with more than 25% of tumors exhibiting high-level amplification compared with the other three subtypes (Figure 1A and Supplementary Table S1).