ABSTRACT
Objective To examine the expression of CD9 protein in pancreatic cancer tissues and adjacent tissues,and to analyze its relation with the progress and prognosis of pancreatic cancer.Methods From September 2005 to December 2009,surgical resected cancer tissues and adjacent tissues of 90 patients with pancreatic cancer and their clinical data were collected.The expression of CD9 protein in pancreatic cancer tissues and adjacent tissues was detected by immunohistochemistry,and its relationship with clinicopathological features was analyzed.Chi-square test was performed for comparison of ratios between groups.Overall survival (OS) analysis of 90 patients after surgery was performed.Results The high expression rate of CD9 protein (64.4％,58/90) in cancer tissue was significantly higher than that in cancer adjacent tissue (45.6％,41/90),the difference has statistically significant (χ2 =6.847,P＜0.05).CD9 protein was highly expressed in most of pancreatic cancer tissue which was well differentiated or without lymph node metastasis (74.6％ (50/67) vs 39.1％ (9/23),χz =9.554,P＜0.01; 50.0％(17/34) vs 73.2％(41/56),χ2 =5.856,P＜0.05 respectively).However,the expression of CD9 was not correlated with gender and age (both P＞0.05).OS and progression-free survival (PFS) of the patients with CD9 highly expressed were significantly longer than those with low expression of CD9 (median OS:33.0 months vs 7.0 months,χ2 =15.400 P＜0.01.Median PFS:30.5 months vs 5.0 months,χ2 =13.750,P＜0.01).Conclusion CD9 protein is a kind of protein related with the invasive ability of pancreatic cancer,which may play a role in progression and metastasis of pancreatic cancer and can help to determine the prognosis to a certain extent.