Abstract:
Objective:To investigate the expression of tight junction associated protein claudin-1 and ZO- 1 in pancreatic carcinoma and its significance in the invasion and metastasis of pancreatic carcinoma. Methods:Immunohistochemistry was used to detect the expression of claudin- 1 and ZO- 1 in different sites of pancreatic carcinoma, including the front-edge area of the pancreatic carcinoma on the borderline to the normal pancreatic tissue, the central area of the carcinoma, the front edge of the tumor adjacent to the peripheral mesenchymal tissue and the normal pancreatic tissue. Results:In the normal pancreatic tissue, claudin- 1 and ZO- 1 were located in the membrane of pancreatic gland alveolus and ductal epithelial cells, but in the pancreatic carcinoma tissue, expression of severe aberrant immunostaining was seen in 66.7% of claudin-1 and 69.2% of ZO-1. The severe ectopic expression rate of claudin-1 of the poorly and undifferentiated pancreatic carcinomas was obviously higher in the tissue of the pancreatic carcinoma adjacent to the normal pancreatic tissue ( 91.7% ) than in the well-differentiated pancreatic carcinoma (55.6%,P<0.05). The severe ectopic expression rate of claudin- 1 was higher in the front edge area of pancreatic carcinoma adjacent to the peripheral mesenchymal tissue ( 89.7%) than in the pancreatic carcinoma next to the normal pancreatic tissue (66.7%,P<0.05). The severe ectopic expression ranked the highest in the lymph node metastases (92.3%, P<0.05). Also, the severe ectopic expression rate of ZO- 1 was higher in the invasive front edge of pancreatic carcinoma adjacent to the peripheral mesenchymal tissue (94.9%) than in the pancreatic carcinoma next to the normal pancreatic tissue (64.2%, P<0.05). The severe ectopic expression ranked the highest in the lymph node metastases ( 100 %,P<0.05). There was a positive correlation between the claudin- 1 and ZO- 1 expressions in various sites of the pancreatic carcinomas. Conclusion: The aberrant expression of claudin- 1 and ZO- 1 may promote the tumorigenesis and development of pancreatic carcinoma. The aberrant claudin-1 expression is in relation to the differentiation of pancreatic carcinoma. The ectopic expressions of claudin- 1 and ZO- 1 may facilitate the invasion and metastasis of pancreatic carcinoma.