Figure 6
Inhibition of autophagy enhances chemotherapy sensitivity. (a) Representative confocal images of GFP-LC3 staining on cells under cisplatin treatment and quantitation of the GFP-LC3-positive cells with the GFP-LC3 dots in the two cell lines. Cells treated with cisplatin or cisplatin combined with 3-MA for 12 h in normal culture condition were observed with the confocal fluorescent microscope. (b) Western blot analysis of LC3 expression on cells with chemotherapy treatment. The QBC and RBE cells were treated with doxorubicin (10 μg/ml) or cisplatin (6 μg/ml) for indicated time. Then the whole-cell lysates were harvested and subjected to western blotting analysis. (c, d) Inhibition of autophagy enhances chemotherapy sensitivity. QBC and RBE cells were seeded at 5 × 103 cells per well (0.2 ml) in 96-well plates and incubated overnight at 37 °C. After exposure to cisplatin (6 μg/ml) or cisplatin combined with 3-MA (10 mmol/l) or wortmannin (5 μmol/l) for 12–72 h, cell viability was assessed at indicated time by Cell Counting kit-8. (e) Knockdown beclin 1 suppressed QBC939 cells proliferation and increased cell sensitivity to cisplatin. QBC cells were infected with AdSi-beclin or AdSi-blank virus for 12 h, treated with or without cisplatin, and then the cells proliferation was determined by CCK-8 for up to 60 h. (f) Deletion beclin 1 induced G2/M phase arrest of QBC cells treated with cisplatin. (g) QBC cells were infected as mentioned above, and then were treated with cisplatin (6 μg/ml) for 48 h. The cells were stained and apoptosis was assessed by flow cytometry. *P<0.05; **P<0.01 (n=3).
