FOXO1 and mantle cell lymphoma: Of the total 1,427 TFs, we identified 4 TFs — EBF1, FOXO1, IRF4, and PAX5 — as the top MCL-selective hits whose sgRNA-mediated targeting had a minimal impact on HEL cell proliferation but caused a severe growth arrest phenotype in all 5 MCL lines (Figure 1, B and C, and Supplemental Figure 1B).