It was found that the epithelial-mesenchymal transition pathway (EMT) plays an important role in the metastasis of malignant tumors such as breast, cervical, lung, and gastric cancers [11–13], and vasopressor 2 (VASH2), a proto-oncogene, was shown to inhibit E-cadherin by activating transforming growth factor β1 (TGFβ1) and hypoxia-dependent GATA3 binding protein (GATA3) thereby inhibiting cadherin expression to promote EMT in human breast cancer (Fig. 4). This evidence concerns the gene CDH17 and breast cancer.