NOTCH1 and breast cancer: Interestingly, EZH2, the histone lysine methyltransferase component of the PRC2 complex, had the largest inverse correlation with PTEN expression in a large cohort of breast cancer cases, and the transcriptional regulator NOTCH1 was also inversely correlated with PTEN expression (Fig. 1d, Supplementary Data 2 for all genes).