Fig. 6
MPT0G211 sensitized MOLT-4 cells to vincristine-mediated mitotic arrest. a Cell cycle distributions of cells exposed to MPT0G211, tubastatin A (TBA), vincristine (VCR), or the indicated combination therapy for 24 h. A statistical analysis of the proportions of cells in the G2/M phase is shown in the right panel. b The levels of the apoptotic proteins caspase 3 and poly-ADP ribose polymerase (PARP) and the pro-survival proteins BCL-XL, BCL-2, and survivin were determined in cells treated with MPT0G211 (3 μM) or TBA (3 μM) in combination with VCR (1 nM) for 24 h. c The protein levels of cyclin B1, aurora B, p-CDC2, p-PLK, p-Histone 3, and MPM2 were evaluated following treatment with a combination of MPT0G211 or TBA with VCR for 24 h. d Cells were co-treated with MPT0G211 or TBA with VCR for 24 h and incubated with an α-tubulin antibody or DAPI. Microtubule dynamics were evaluated using a ZEISS LS 510META confocal microscope (magnification × 630). Scale bar = 20 μM. e Antitumor activity of MPT0G211 plus vincristine in a MOLT-4 xenograft model. When the tumor size reached 200 mm3, mice were injected with vehicle, vincristine (1 mg/kg, i.p., qwk), and MPT0G211 (30 mg/kg, i.p., qd) alone or a combination of both. The curves of tumor growth volume were expressed as mean ± SEM. f Changes of body weight after treatment. Data are shown as means ± standard errors of the means. *p < 0.05, **p < 0.01, and ***p < 0.001 versus the control group