Figure 6

Genetic inhibition of autophagy reduces metformin-mediated apoptotic cell death. (A) Western blot analysis of Beclin1 expression in siBeclin1 and control Ishikawa cells. (B) Beclin1 expression was blocked in Ishikawa cells by Beclin1 siRNA; cells were incubated with the indicated concentrations of metformin for 48 h. Cells were then harvested and analyzed by flow cytometry. *p < 0.05 and **p < 0.01 vs. Control siRNA cells. (C) Beclin1 siRNA Ishikawa cells were incubated with the indicated concentrations of metformin for 48 h. Cells were then lysed to measure caspase-3/7 activity. *p < 0.05 and **p < 0.01 vs. Control siRNA cells. (D) Beclin1, LC3B, p62, and cleaved PARP expression were examined in siBeclin1-treated and control cells. Actin expression was used as a loading control.