Stabilization of p27 in the nucleus attenuates BCR-ABL1–induced leukemia. (A) BM cells from p27^+/+ and p27^T187A mice were transduced with BCR-ABL1 retrovirus, sorted by FACS for GFP⁺/Lin⁻ cells, and plated in methylcellulose in the presence or absence of cytokines. Myeloid colony formation of BCR-ABL1–transduced cells was assessed after 8 days. (B) p27^+/+ mice were transplanted with BCR-ABL1–transduced BM cells from p27^+/+ and p27^T187A mice and survival was analyzed using Kaplan-Meier statistics. (C) WBC and PLT counts and (D) spleen and liver weights of leukemic mice were compared according to genotype. (E) Lineage distributions of GFP⁺ cells in the bone marrow and spleen of leukemic mice: granulocytes (Gr1⁺CD11b⁺), B cells (CD19⁺), T cells (CD3⁺), and LKS cells (Lin⁻c-Kit⁺Sca1⁺). Error bars represent standard deviation. (F) Representative histological sections of BM, liver, lung, and spleen from mice transplanted with BCR-ABL1–transduced BM cells from p27^+/+ and p27^T187A mice. Scale bars represent 100 μm. In the above experiments, *P < .050, **P < .010. PLT, platelet.