Lmo2 and LYL1 are coexpressed in ETP-ALL, and LYL1 is required for maintenance of ETP-ALL lines. (A) Gene set enrichment analysis of Lmo2-upregulated genes in ETP vs non-ETP T-ALL. Lmo2-upregulated genes10 were compared with microarray data from patient samples of ETP and non-ETP T-ALL.8 The enrichment plot (left) shows skewing to the left, indicating association with the ETP subclass of T-ALL. The heat map (right) shows the “leading edge” genes that are most associated with ETP-ALL. Arrowheads indicate LMO2 and LYL1. FDR, false discovery rate; NES, normalized enrichment score. (B) Real-time PCR showing expression of LYL1 in the indicated cell lines. (C) Growth curves of the indicated cell lines infected with the indicated LYL1 knockdown lentiviral vectors and selected in Puromycin. (D) Real-time PCR showing expression of LYL1 in K562 cells infected with the indicated LYL1-knockdown lentiviral vectors and selected in Puromycin.