NOTCH1 and acute lymphoblastic leukemia: Chromatin immunoprecipitation sequencing (ChIP-seq) revealed a notable loss of H3K27me3 on NOTCH1 target genes that overlapped with regions of NOTCH1 binding within the target gene transcriptional start sites.66 This implies that NOTCH1 signalling is normally associated with reduced PRC2 complex activity.66 These observations further support a functional association between the PRC2 complex and NOTCH1 signalling, highlighting that co-operation between PRC2 loss and NOTCH1-activating mutations can lead to enhanced tumorigenic potential in T-ALL cases.