DT2216 alone or in combination with AZA can effectively reduce the colony-formation ability of JAK2-mut AML CD34⁺ primary leukemia cells. (A) Viability of CD34⁺ AML cells isolated from patients with post-MPN AML treated with the indicated concentrations of DT2216 for 24 hours. Note: Patient 7’s samples included total leukemia cells. (B) BH3 profiling of cells from 2 patients with post-MPN AML and MOLM13 cells (as a control). (C) Colony formation for CD34⁺ AML cells isolated from patients with JAK2-mut AML and treated with DT2216 (50 nM) and/or AZA (100 nM) in methylcellulose for 10 to 14 days. Colonies were counted using the EVOS imaging system (Thermo Fisher Scientific, Bothell, WA) and significance determined by t test. ∗∗P < .01; ∗∗∗P < .001; ∗∗∗∗P < .0001. (D) Western blot analysis confirmed that DT2216 alone or in combination with AZA can effectively target and degrade BCL-xL in cells collected from methylcellulose. α-tubulin was used as the loading control for the western blot. ns, nonsignificant; Pt, patient.