Figure 3.

Epidermal growth factor treatment promotes the migration but not the proliferation of breast cancer cells. (a) Proliferation as measured by an Alamar Blue proliferation assay was not significantly affected in serum-starved cells of either cell type over a period of 72 hours. (b) Epidermal growth factor (EGF) treatment (100 ng/ml) enhanced MDA-MB-231 cell and MCF-7 cell migration as measured by a scratch-wound migration assay. Healing due to cell migration was measured over a period of 48 hours following wounding. The difference in migratory ability induced by EGF was significant in both cell types (P = 0.0483 and P = 0.013 at 48 hours for MDA-MB-231 cells and MCF-7 cells, respectively). (c) Treatment of both EGF-treated MDA-MB-231 and EGF-treated MCF-7 cells with the epidermal growth factor receptor kinase inhibitor PD153035 (PD) significantly inhibited wound healing in serum-containing medium (P = 0.0004 and P = 0.0006 at the end points, respectively). (D) Treatment of both MDA-MB-231 cells and MCF-7 cells with PD significantly inhibited wound healing in serum-containing medium (P = 0.028 at 24 hours and P = 0.0264 at 48 hours, respectively).