NOTCH1 and acute lymphoblastic leukemia: Despite the key role of EZH2 in repressing Notch signaling in T-ALL, a positive correlation between EZH2 and Notch was found in glioblastoma and breast cancer in which EZH2 directly binds Notch1 promoter, upregulating Notch1 expression without any change in H3K27me3 levels [298,299].