Figure 5

Ectopic expression of FOXO3a in estrogen-dependent breast cancer cells suppresses cell proliferation in cell culture. (a) Growth of forkhead box class O (FOXO)3a over-expressing MCF7-FO (MCF7-FO10, MCF7-FO33, and MCF7-FO41) cells and control (MCF7-C4, MCF7-C5, and MCF7-C12) cells in the absence of 17β-estradiol (E2) was determined by counting trypan-blue stained cells with a hemocytometer. Growth curves are the means of the three MCF7-FO cell lines (MCF7-FO10, MCF7-FO33, and MCF7-FO41) and the three control cell lines (MCF7-C4, MCF7-C5, and MCF7-C12); error bars indicate standard deviation from three experiments. (b) Growth of the same sets of cells in the presence of E2 (1 nmol/l). Growth curves are the means of the three MCF7-FO cell lines (designated MCF7-FO average) and the three control cell lines (designated MCF7-C average); error bars indicate standard deviaton from three experiments. *P < 0.05 between control MCF7-C group versus MCF7-FO group.