Consistently, immunoblot analysis of a panel of MCL cell lines revealed that FOXO1, along with EBF1, IRF4, and PAX5, was highly expressed in MCL cells, in contrast to AML cells, which barely expressed any of the 4 MCL lineage-survival TFs (Supplemental Figure 4A and Supplemental Figure 5B). Here, PAX5 is linked to mantle cell lymphoma.