Decreased expression of cell cycle– and apoptosis-related genes in Aml1-excised leukemia cell. (A) Expression analyses of p19^ARF, p53, Bax, and p21^CIP1 by quantitative real-time PCR. The expression of each mRNA, normalized to that of Gapdh, is shown as the ratio to that of the normal BM mononuclear cells. (B) Intracellular staining of p53 in MLL-ENL leukemic cells was detected by flow cytometry. Representative histograms are shown. (Left) Staining with AlexaFluor-647–conjugated IgG1 isotype control antibodies. (Right) Staining with AlexaFluor-647–conjugated anti-p53 antibodies. Expression analyses of (C) Meis1 and Hoxa genes and (D) Bmi1 and p16^INK4A by quantitative real-time PCR. Error bars represent SD. *P < .05. We performed 3 independent experiments and confirmed that similar results were reproduced. Statistical significance was evaluated by unpaired t test.