HOXA9 and MN1-TEL cooperatively cause acute myeloid leukemia (AML) in mice. (A) Expression of HOXA9 in AML patient samples with MN1-TEL. A quantitative RT-PCR result is shown. NBM indicates control normal BM (n = 3); and Pt, patient samples (n = 2). (B) Retroviral transduction of MN1-TEL⁺ BM cells. Sorted MN1-TEL⁺ or MN1-TEL^- Lin^- BM cells were transduced with pSRα-HOXA9-IRES-YFP (HOXA9) or pSRα-IRES-YFP (vector) retrovirus. The FCM analysis of GFP/YFP expression in MN1-TEL⁺ BM cells transduced with HOXA9 virus is shown on the right. Control indicates uninfected WT BM cells. (C) Survival analysis. Retrovirally transduced BM cells (MN1-TEL⁺/HOXA9⁺, MN1-TEL⁺/Vector, MN1-TEL^-/HOXA9⁺, MN1-TEL^-/Vector) were transplanted into lethally irradiated syngeneic recipients (n = 10 in each group). Survival curves were generated by the Kaplan-Meier method. ○ indicates AML; and •, T-lymphoid leukemia.