Figure 4

SEM ×4000 (bar 2 μm). HT-29 and inserts (×8000) (bar 1 μm). a. untreated cells. Evident cellular boundaries. Insert: short microvilli are present. b. EGF treated cells. Same morphology as untreated cells. c. 10 nmol/L cetuximab treated cells. Filopodi are evident. Insert: microvilli reduction is evident. d. 10 nmol/L cetuximab plus 10 nM EGF treated cells. Filipodi and some vesicles are evident. Insert: microvilli reduction is evident. e. 1 μmol/L gefitinib treated cells. Some vesicles are evident. Insert: microvilli reduction is evident. f. 1 μmol/L gefitinib plus 10 nM EGF treated cells. Lamellipodi, some vesicles and weak contacts with nearby cells are evident. Insert: microvilli reduction is evident.