Figure 1: The expression of HER-2 oncoprotein in various human breast cancer cell lines. Cells were lysed and analyzed by western blot as described in methods. As revealed in figure, BT-474 and SKBr-3-hr were HER-2-overexpressed breast cancer cell lines. Whiles MCF-7, MCF-10A, and MDA-MB-231 cells were HER-2-unexpressed breast cancer cells.