NP23 pro–B-1 ALL gene signature is enriched in pediatric ALL with CRLF2 rearrangements. (A) Hierarchical clustering of RNA-seq samples showing that NP23 pro–B-1 ALL expression profile is distinct from that of murine pre–B-2 ALL (taken from Eμ-RET and E2A-PBX mice). (B) GSEA plot showing enrichment of NP23 pro–B-1 ALL gene signature in pediatric ALL carrying CRLF2 rearrangements (GSE26281). The gene signature was generated by comparing NP23 pro–B-1 ALL with mouse pre–B-2 ALL (FPKM FC>2).