EGF is a chemo-attractant protein that induces the growth, proliferation, and migration of epidermal and epithelial cells, including endometrial cells, through the activation of the extracellular signal-regulated kinase 1/2 (ERK1/2) signaling pathway [47,48,49] and high levels of this factor may not be helpful in the case of endometriosis. The gene discussed is EGF; the disease is endometriosis.