Deletion of the AML1 gene after MLL-ENL induction accelerates the onset of leukemia in transplanted mice. (A) BM cells from Aml1^f/f; Mx-Cre (+) or Aml1^f/f; Mx-Cre (−) were transduced with MLL-ENL and transplanted into congenic mice. Injection with pIpC was performed 3 to 4 weeks after transplantation, so that the Aml1 gene was excised in transplanted Aml1^f/f; Mx-Cre (+) cells (Aml1^Δ/Δ). (B) Survival curves of the recipient mice. Data from 10 mice for each group are shown. Arrowheads indicate pIpC injection. Comparison of survival curve was performed using log-rank test.