Possible involvement of Bahcc1 in myeloid immortalization by conditional expression of MLL-ENL. (A) Initial screening strategy of candidate genes involved in differential modes of myeloid immortalization using induced ST-HSCs and MPP2 cells by RNA seq. (B) Numbers of differential expression genes (DEGs) screened by RNA seq in comparisons 1 (log2 FC>1 in induced ST-HSCs and log2 FC >0 in induced MPP2 cells, with adjusted P values <.05) and 2 (log2 FC >1 in induced MPP2 cells and log2 FC >0 in induced ST-HSCs, with adjusted P values <.05). Genes abundantly detected (count per million [CPM] >10 in induced ST-HSCs and MPP2 cells, and their respective controls) were focused on. (C) Refinement of focused genes based on exclusive enhancement in CD34 (−) KSL cells conditionally expressing MLL-ENL in the previous study.⁹ Bahcc1 and Pik3r6 were selected from the focused genes among DEGs. Overlap of the focused genes in comparisons 1 and 2 is also shown. (D) Representative FACS plots and quantification of HSPCs based on CD150/CD48 expression in CD34(−) and CD34(+) KSL cells. (E) RT-qPCR of Bahcc1 in myeloid immortalization assays using the same samples as shown in Figure 1E. Colors and patterns of bars are the same as shown in Figure 1E. Bar graphs show the mean with SD of at least 3 independent experiments. ^∗P < .05; ^∗∗P < .01; ns, not significant (ANOVA followed by Tukey-Kramer multiple comparisons and unpaired Welch t test for panel E).