Polyphyllin VII Promotes Apoptosis and Autophagic Cell Death via ROS-Inhibited AKT Activity, and Sensitizes Glioma Cells to Temozolomide

Figure 4

Autophagy is involved in the antiglioma effect of PP7. (a–c) Western blots and corresponding quantification analysis show the effect of 3-MA in respect to increased SQSTM1 (p62), decreased LC3II protein levels, and the decrease in LC3 II/LC3 I ratio in U87-MG cells and (d–f) in U251 cells. U87-MG and U251 cells were subsequently treated with 3 μM PP7 and 3 μM PP7, respectively, and with 5 mM 3-MA. 3-MA was added 3 h after adding PP7, while the overall treatment lasted 8 h. (g–i) Representative images and quantification analysis display decrease in LC3 puncta after PP7 and 3-MA combined treatment in U251 and U87-MG cells. Ctr represents cells treated only with solvent. (j, k) Cytotoxic effect induced by PP7 was partly rescued by 3-MA treatment in U87-MG and U251 cells. U87-MG and U251 cells were treated with 6 μM and 4 μM PP7, respectively, alone or in combination with 3-MA (5 mM) for 24 h. (l, m) Cytotoxic effect induced by PP7 was partly rescued by Baf-A1 treatment in U87-MG and U251 cells. U251 and U87-MG cells were treated with 4 μM and 6 μM PP7, respectively, alone or in combination with bafilomycin A1 (10 nM) for 24 h. stands for the repetition of experiments. , , .

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