Aggressive breast cancer-derived cell lines, Hs578T, MDA-435, MDA-231 and BT549, showed increased levels of EphA2 receptor compared to human mammary epithelium-derived cell lines, MCF-10A, MCF-12A and MCF-10-2 where normal levels of EphA2 are expressed [23, 29, 30]. This evidence concerns the gene EPHA2 and breast carcinoma.