Fig. 2

Droxinostat induced apoptosis in colon cancer cells. a and b – HT-29 cells were treated with droxinostat for 12 and 24 h. Cellular apoptosis was measured with annexin V and PI staining. The percentages of positive cells in the upper right and lower right quadrants represent later and early apoptotic cells, respectively. Data are expressed as the means ± SD of three independent experiments. **p < 0.01 vs vehicle. c – HT-29 cells were treated with 10 μM Z-VAD-FMK followed by 21 μM droxinostat treatment for 24 h. Cellular apoptosis was measured using annexin V and PI staining. Apoptotic data are expressed as the means ± SD of three independent experiments. *p < 0.05 vs. vehicle, **p < 0.01 vs. vehicle, ^##p < 0.01 vs droxinostat. d – HT-29 cells were treated with 10 μM Z-VAD-FMK followed by 21 μM droxinostat treatment for 24 h. The activity of caspase-3 was measured at 405 nm and expressed as optical density (OD). e and f – HT-29 cells were incubated with droxinostat for 24 h. Expressions of pro- and anti-apoptotic related genes were measured using RT-PCR. **p < 0.01, ***p < 0.001 vs Veh; ^#p < 0.05, ^###p < 0.001 vs droxinostat