ESR1 and breast carcinoma: However, studies show that EGF is likely to induce tumor cell invasion in breast cancer (Klijn et al., 1992; Chrysogelos and Dickson, 1994; Hardy et al., 2010), where the overexpression of EGFR is connected with the loss of estrogen receptor and poor prognosis (Chrysogelos and Dickson, 1994).