Since Liu Yang et al. reported in 2007 that mice heterozygous for the FOXP3 mutation spontaneously develop mammary cancer at a high rate16, it has become apparent that FOXP3 plays an important suppressive role in breast cancer development by controlling the expression of a series of oncogenes, such as ERBB2, MYC and SKP2, in epithelial cells16, 17, 19, 20. Here, ERBB2 is linked to breast cancer.