NOTCH1 could inhibit downstream E-cadherin by activating Slug in mammary epithelial cells, and finally promote the epithelial cells transform to stromal cells [18], and it can down-regulate MEF2 by activating Snail1 in embryonal rhabdomyosarcoma, thus suppressing cell differentiation and intensifying the characteristics of stem cells in tumor cells [19]. The gene discussed is SNAI1; the disease is neoplasm.