EGFR and cancer: In different cancer cells, we observed that lysosomal functions are stimulated by docetaxel treatment, as evidenced by (i) an increase in lysosomal acidification (reduced lysosomal PH) (Fig. 1c−e and SF. 1a), (ii) enhanced lysosomal cathepsin B activity (SF. 1b and 1c); and (iii) increased lysosomal degradative activity with EGFR degradation (Fig. 1f).