Effect of apigenin and cisplatin on proliferative inhibition of different cancer cell lines, determined by MTT assay. MCF-7, A549, HeLa, HCT 116, or H1299 cells were treated with 30 µM apigenin for 2 h, followed by different concentrations (0, 2.5, 5 or 10 µM) of cisplatin for a further 48 h. The bars represent mean + standard deviation of results obtained from three independent experiments.