A previous study showed that loss of E-cadherin expression is one of the earliest steps in EMT, and is a hallmark of EMT.25 To elucidate the effects of Notch3 on EMT progression in breast cancer cells, we first established a N3ICD stable transfectant in low Notch3-expressing MDA-MB-231 cells by co-transfecting pCLE/N3ICD and pEGFP-N plasmids. The gene discussed is NOTCH3; the disease is breast carcinoma.