Fig. 1

HER2 down-regulation induces autophagy in primary tumor cells in vitro. (A-E) MTB/TAN primary tumor cells subjected to doxycycline withdrawal for 24 h. Treatment with 50 µM chloroquine (CQ) for 24 h was used as a positive control for the induction of autophagy. (A) HER2 levels and conversion of LC3-I to LC3-II determined by western blotting. β-tubulin is shown as a loading control. (B) Representative images of double­membraned autophagosomes (arrows) visualized by electron microscopy. Bar = 500 nm. (C) Quantification of autophagosomes per cell in (B). (D) Representative images of subcellular localization of EGFP-LC3 visualized by fluorescence microscopy. Original magnification, x400. (E) Quantification of average EGFP-LC3 punctae per cell in (D). Data represent mean ± SEM **P < 0.001, ***P < 0.0001