EGFR Tyrosine Kinase Inhibitors Activate Autophagy as a Cytoprotective Response in Human Lung Cancer Cells
Figure 1
EGFR-TKIs dose- and time-dependently induced the formation of LC3-II, and formation of autolysosomes in lung cancer cells.
A and B, lung cancer cells were incubated with varying concentrations of gefitinib or erlotinib for 24 hours or incubated with 25 µM gefitinib or erlotinib for appropriate intervals. The switch of LC3-I to LC3-II was detected by immunoblotting. C, A549 or NCI-H1299 cells were treated with DMSO or 25 µM gefitinib for 24 h. Cells were labeled with fluorescence and imaged by confocal microscope. Red, lyso tracker-labeled lysosomes; Green, FITC-labeled LC3; Blue, DAPI-labeled nucleus. The overlay was shown in the right column. The orange-stained cells indicated LC3 co-located with lysosomes.