Figure 4
Estrogen suppresses induction of apoptosis by phosphatidylinositol-3-kinase pathway inhibitors. (a) Estradiol suppresses induction of apoptosis by BGT226. Cells cultured without or with 10 nmol/l 17β-estradiol (E2) were treated with 10 nmol/l BGT226, and apoptosis was measured after 4 days of treatment. Results are from at least three replicates for each treatment condition per cell line. Significant suppression of apoptosis by E2 is indicated (*P < 0.05). Suppression of phosphatidylinositol-3-kinase inhibitor-induced apoptosis by E2is dose dependent. Cells cultured without or with 10 nmol/l E2 were treated with the indicated concentrations of (b) BGT226 or (c) BKM120 and apoptosis was measured after 4 days of treatment. Results are from at least three replicates for each treatment condition per cell line. Significant induction of apoptosis in estrogen-deprived cells is indicated (*P < 0.05). Suppression of apoptosis by E2 in drug-treated and nontreated cells is indicated (#P < 0.05).