Fig. 1

Effects of SK, 4-OHT, and the combination on cell proliferation. a The proliferation inhibition rate of MCF-7 cells treated with SK (2, 3, 4 μM), 4-OHT (15, 17.5, 20 μM), or the combination at 24 h. Q < 0.85 suggests antagonism between the two drugs, 0.85 ≤ Q<1.15 addition of their effect, and Q ≥ 1.15 synergism between them. b The proliferation inhibition rate of MDA-MB-435S cells treated with SK (2, 3, 4 μM), 4-OHT (15, 17.5, 20 μM), or the combination at 24 h. Data are representative of three independent experiments. Each value represents the mean ± S.E.M (n = 3)