Besides, an increasing number of studies reported that estrogen signal induced the expression of metastasis-related genes, such as AGR2 [51], Gab2 [40], LMO4 (Lim only protein 4) [52], etc. These protein expressions in breast tumors have been found to be highly correlated with poor prognosis and low survival. The gene discussed is AGR2; the disease is breast neoplasm.