Fig. 1.

Effect of PLE on growth of human colon and lung cancer cells. HCT116 and H1299 cells were treated with PLE at the concentrations of 0, 87.5, 175, and 350 µg/ml for 72 h and 96 h. Viable cells were quantified by the MTT assay, and data are shown as mean ± SE of 4-8 determinations. Different letters (a-d) indicate statistical differences among different concentrations of PLE at a specific time point by Tukey's test (P < 0.05).