Annexin V/PI double staining assay.

<p>Cells were exposed to either 0.2% DMSO (vehicle control), 5.0 µM paclitaxel (positive control), or α-tomatine for the indicated time. The treated cells were stained with Annexin V and PI and then subjected to FACS analysis. The percentages of early apoptotic cells (Annexin V positive, PI negative) and late apoptotic cells (Annexin V and PI positive) observed at different incubation time with α-tomatine are shown. Results are presented as the mean ± SD of three independent experiments. * <i>P</i><0.05, ** <i>P</i><0.01, *** <i>P</i><0.001 <i>vs</i> vehicle control.