Fig. 9

G-4 (10 μM) induced apoptosis and suppressed cell colony formation, migration and invasion. a Flow cytometric analysis for apoptosis. HCT8/Tax and HCT15/Tax cells were treated with G-4 for 48 h. Taxol-treated cells were used in parallel as a control. b Effect of G-4 on cell colony formation. HCT15/Tax cells were seeded into 6-well plates and 9 days later, the colonies were stained with crystal violet, photographed (upper panel) and counted (lower panel). Scale bar: 5 mm. c Effect of G-4 on cell migration in HCT15/Tax cells. Cells were seeded into 6-well plates at 70–80% confluence. Cell migration was monitored by optical inspection for 24 h using a microscope and pictures were taken at 0 and 24 h (upper panel) and quantified (lower panel). d Effect of G-4 on cell invasion in HCT15/Tax cells. Invasion assay was conducted utilizing transwell chambers. The invaded cells were photographed (upper panel) and quantified (lower panel). Data are representative of at least three independent experiments. Error bars represent SD. **P < 0.01 compared with Taxol. G-4 and Taxol was applied at10 and 1 μM respectively. HCT8/Tax and HCT15/Tax:Taxol- resistant HCT8 and HCT15 cell lines. G-4: GCCSysm-4, Tax:Taxol