FIGURE 5.

PE induces S cell cycle arrest via ER stress in SMMC-7721 cells. (A) S cell cycle arrest in PE-treated SMMC-7721 cells. Cells were incubated with indicated concentrations of PE for 24 h. Propidium iodide staining and flow cytometry were used to determine the proportion of cells in various phases of the cell cycle. (B) Representative immunoblots against Cyclin A2, CDK2, and β-actin from SMMC-7721 cell lysates after treated with PE (0, 3, 10, and 30 μM) for 24 h. β-Actin was taken as control. Blots are representative of three independent experiments. Values were expressed as mean ± SD of three independent experiments. ^∗P < 0.05, ^∗∗P < 0.01 versus control cells cultured with 0.1% DMSO by one-way ANOVA and post hoc tests. (C) The effects of CHOP knockdown on cell cycle arrest. SMMC-7721 cells were transfected with Luc siRNA or CHOP siRNA for 24 h, followed by incubation with 30 μM of PE for another 24 h. (D) Representative immunoblots against Cyclin A2, CDK2, and β-actin from cell lysates of Hep G2 treated with PE (0, 3, 10, and 30 μM) for 24 h. β-Actin was taken as control. Blots are representative of three independent experiments. Values were expressed as mean ± SD of three independent experiments. ^∗P < 0.05, ^∗∗P < 0.01 versus control cells cultured with 0.1% DMSO by one-way ANOVA and post hoc tests.