Notch-1-mediated esophageal carcinoma EC-9706 cell invasion and metastasis by inducing epithelial-mesenchymal transition through Snail.

Notch has recently been shown to promote epithelial-to-mesenchymal transition (EMT) by involving in the EMT process that occurs during tumor progression and converts polarized epithelial cells into motile, invasive cells. However, it is still unclear whether the Notch signaling pathway is associated with the regulation of EMT in esophageal carcinoma. The present study explored Notch-1-mediated esophageal carcinoma EC-9706 cell invasion and metastasis by inducing epithelial–mesenchymal transition through Snail. The results demonstrated that the inhibition of Notch-1 expression in the esophageal carcinoma cell line EC-9706 could suppress the occurrence of EMT and at the same time could decrease the invasion and metastasis ability of the EC-9706 cells, indicative of its role in EMT. Snail is a transcriptional repressor of E-cadherin. We found that with the inhibition of Notch-1 expression in the esophageal carcinoma cell line EC-9706, the expression of Snail also decreased. Mechanistic studies showed that the up-expression of Snail in the EC-9706 cells restored the suppression of EMT regulated by Notch-1 inhibition, suggesting the role of Snail in Notch-1-mediated EMT. At the same time, the up-expression of Snail in the EC-9706 cells could also rescue the invasion and metastasis ability inhibited by Notch-1 siRNA. Taken together, our results had revealed that Notch-1 could participate in the invasion and metastasis of esophageal carcinoma through EMT via Snail. This study indicated that Notch-1 might be a useful target for esophageal carcinoma prevention and therapy.