(A) Cells from TKI-resistant BC CML patients (Table 1, n = 6) were treated with ABT-199, nilotinib, or both. Apoptosis in bulk, CD34+CD38−, and CD34+CD38+ cells was assessed after 48 hours. (B) Normal BM cells were treated with ABT-199, nilotinib, or both. Apoptosis in CD34+ cells was assessed after 48 hours. (C) Cells from TKI-resistant BC CML patients were treated with ABT-199, nilotinib, or both for 24 hours. Protein expression in the cells was examined using immunoblot, and mRNA expression using real-time RT-PCR analysis. (D) Cells from TKI-resistant BC CML patients were treated with siRNAs against Bcl-XL, Mcl-1, or both for 24 hours and then with ABT-199 for 48 hours. Cell death was then assessed. CON, control; Nil, nilotinib; AnnV, annexin V.