The effect of exemestane on apoptosis of H23 and A549 cells. A: Flow cytometry analysis of H23 and A549 following exposure to exemestane. A representative image from three independent experiments is shown. H23 cells. C: Control and E 50 μM: Exemestane 50 μM. A549 cells. C: Control and E 20 μM: Exemestane 20 μM. B: Results are expressed as the % percentage of Annexin+ cells ± SEM compared to untreated cells from at least three independent experiments. Asterisks denote a statistically significant difference (unpaired t-test) compared to untreated cells (C). ** P < 0.01 and *** P < 0.001.