摘要AIM: To examine the expressions of N-cadherin and E-cadherin in specimens of 62 normal esophageal epithela, 31 adjacent atypical hyperplastic epithelia and 62 esophageal squamous cell carcinomas (ESCCs), and to investigate the roles of N-cadherin in the invasiveness of ESCC cell line EC9706 transfected by N-cadherin shRNA. METHODS: PV immunohistochemistry was used to detect the expression pattern of N-cadherin and E-cadherin in specimens of 62 normal esophageal epithelia, 31 adjacent atypical hyperplastic epithelia and 62 ESCCs. The invasiveness of ESCC line EC9706 was determined by transwell assay after EC9706 was transfected by N-cadherin shRNA. RESULTS: The positive rates of N-cadherin decreased in the carcinoma, adjacent atypical hyperplastic and normal esophageal tissues (75.8%, 61.3% and 29.0%, P < 0.05), respectively, while those of E-cadherin increased (40.3%, 71.0% and 95.2%, P < 0.05). The increased expression of N-cadherin and decreased expression of E-cadherin were related to invasion, differentiation, and lymph node metastasis ( P < 0.05). The expression level of N-cadherin decreased in the N-cadherin knocked down cells, and the invasiveness of those cells decreased significantly as well. The number of cells which crossed the basement membrane filter 0.05). CONCLUSION: E-cadherin and N-cadherin expression is correlated with the invasion and aggravation of ESCC. The down-regulation of N-cadherin lowers the invasiveness of EC9706 cell line.