Fig. 4.

Dose-dependent proapoptotic effects of genistein on HT29 cells, as determined by RT-PCR and flow cytometry. The relative gene expression of caspase-3 in HT29 cells upon exposure to 0, 30, 50 and 70 µM genistein was examined by RT-PCR. Caspase-3 gene expression was increased by increasing genistein concentrations compared with 18S rRNA gene expression (top). Genistein also induced significant apoptosis in HT29 cells by increasing caspase-3 protein compared to untreated cells, as determined by flow cytometry (bottom). One-Way-ANOVA analysis was performed to compare differences between groups. (*) and (**) indicate significant difference at P< 0.05 and P< 0.01 levels compared with untreated cells, respectively