Fig. 3

SAHA-sensitized MOLT-4 cells to vincristine-mediated mitotic arrest. a Tubulin assembly was determined by an in vitro tubulin polymerization kit and then detected by spectrophotometry. Paclitaxel (10 μM) and vincristine (10 μM) were used as positive controls. Paclitaxel is a polymerizing agent and vincristine is a depolymerizing agent. S 5 represents SAHA 5 μM, and S 50 + V 3 represents SAHA 50 μM combined with vincristine 3 μM. This experiment was examined in a cell-free condition. b MOLT-4 cells were treated with SAHA and vincristine alone or co-treatment for 24 h and then stained with β-tubulin and DAPI. The immunofluorescence images were captured by the ZEISS LSM 510 META confocal microscope. All images were under × 400 microscopic magnification. a control, b 500 nM SAHA, c 3 nM vincristine, d SAHA combined with vincristine, e 30 nM vincristine, f 30 nM paclitaxel. c Cells were treated with vincristine (0.3, 1, and 3 nM) alone or co-treated with SAHA (500 nM) for 24 h. Then, total cell lysates were obtained to evaluate the G₂/M phase regulatory protein expression and the tubulin acetylation. Data are expressed as mean values ± SD of at least three separate determinations. S SAHA, V vincristine