In breast cancer, BRCA1 gene may induce STC1 to express (Welcsh et al. 2002); STC1 and STC2 (Bouras et al. 2002) in tumor tissues indicate over expression in ER+ breast cancer cells, hormones is an essential element to regulate the expression of STC2 (Raulic et al. 2008). The gene discussed is ESR1; the disease is breast cancer.