Fig. 2

Flavone, apigenin, and luteolin induced cell cycle arrest and apoptosis in human breast cancer cells. a MCF-7, b Hs578T, and c MDA-MB-231 cells were treated with the IC₅₀ concentrations (Table 1) of flavone, apigenin, and luteolin for 24 h prior to cell cycle analysis by propidium iodide staining. The percentage of cells in each phase of the cell cycle (sub G1, G0/G1, G2/-M and S) is indicated. d The effects of flavone, apigenin, and luteolin on cyclin B and cyclin D1 protein expression. Western blot analyses were performed on cell lysates form MCF-7 cells treated with the IC₅₀ concentrations (Table 1) of flavone, apigenin, and luteolin for 24 h. e Flavone, apigenin, and luteolin induced apoptosis in MCF-7, Hs578T and MDA-MB-231 breast cancer cells as detected by Hoechst 33342 staining. The breast cancer cells were treated with the IC₅₀ concentrations (Table 1) of flavone, apigenin. and luteolin. f Quantification of Hoechst 33342 staining of untreated MCF-7, Hs578T and MDA-MB-231 cells (control) and cells treated with flavone, apigenin, and luteolin. g Western blot analyses for cleaved-PARP, tumor p53, and cytochrome c in MCF-7 cells treated with the IC₅₀ concentrations (Table 1) of the flavone, apigenin and luteolin from 24 h. Results are the mean ± standard deviation of three independent experiments. P < 0.05 is considered as statistically significant. Symbols: *: P < 0.05; #: P < 0.01; ★: P < 0.001