Fig. 5

Effects of EGF on EGFR expression and distribution in gastric cancer cells with knockdown of CD24. a SGC-7901 b BGC-823 and c AGS-1 cells transfected with control siRNA or siCD24 were in serum-free media overnight and incubated with EGF 20 ng/mL for indicated times, and then proteins extracted from the lysates were subjected to Western blotting assays to detect the expression of EGFR. GAPDH is used for control. d SGC-7901 and e AGS-1 cells transfected with control siRNA or siCD24 were in serum-free media overnight and incubated with EGF 20 ng/mL for 15 min, and representative microscopy images of SGC-7901 and AGS-1 cells stained for EGFR are shown. Cell nuclei were labeled with DAPI. Scale bar 10 μm. f SGC-7901 cells transfected with control siRNA or siCD24 were in serum-free media overnight. In addition to its protein synthesis blocked with cycloheximide (CHX, 10 μg/mL), the cells were then stimulated with EGF (20 ng/mL) for the indicated times. Then, the cells were lysed and EGFR level was determined by Western blotting assays. EGFR bands were quantified and normalized against GAPDH (graph on the right). Asterisk P < 0.05 in the siCD24 cells relative to siRNA control cells