PROM1 and acute lymphoblastic leukemia: Cluster 4 is specific to AML and ALL data sets with low activity across all FBM cell types (Supplemental Fig. S3D) and includes MAZ and PROM1. Cluster 5 is inactive in all of the data sets, and pathway enrichment implies this represents an immortalized cell program (e.g., cell junction organization) (Supplemental Fig. S3C).