Objective To investigate the expressions of microRNA-21 in cholangiocarcinoma tissues and the relationship between epithelial mesenchymal transition (EMT) and the prognosis of patients.
Methods Forty-one samples of cholangiocarcinoma and 10 samples of adjacent tissues from 10 patients who received radical resection of cholangiocarcinoma at the Provincial Hospital of Anhui Medical University from January 2005 to January 2010 were collected. The expressions of microRNA-21, E-cadherin and N-cadherin were detected by in situ hybridization and immunohistochemistry, and effect of their expressions on the prognosis was analyzed. Enumeration data were analyzed using chisquare test. The correlation between microRNA-21 and EMT markers was analyzed using the Spearman correlation coefficient. The survival curve was drawn by KaplanMeier method, and the survival rate was analyzed using the Log-rank test.
Results The expression rate of microRNA-21 in the cholangiocarcinoma tissues was 63%, which was significantly higher than 30% of that in the adjacent tissues (χ2=0.324, P<0.05). The expression of microRNA-21 was closely related with the tumor differentiation degree, lymph node metastasis, perineural invasion (χ2=6.365, 0.552, 11.896, P<0.05), but not with gender, age, tumor location and tumor type (χ2=0.322, 0.588, 0.510, 0.256, P>0.05). The expressions of Ecadherin and Ncadherin were related with lymph node metastasis and perineural invasion (χ2=4.630, 5.512; 6.600, 7.152, P<0.05), but not with gender, age, tumor location, tumor differentiation degree and tumor type (χ2=0.266, 0.013, 0.067, 0.666, 0.003; 1.036, 0.997, 1.808, 2.997, 0.812, P>0.05). A positive correlation between the expression of microRNA-21 and EMT related markers E-cadherin and N-cadherin was detected (r=0.373, 0.614, P<0.05). The results of survival analysis showed that the overall survival rate and tumor-free survival rate of patients with low expression of microRNA-21 were significantly higher than those of high expression of microRNA-21 (χ2=3.999, 4.376, P<0.05).
Conclusion Over expression of microRNA-21 in cholangiocarcinoma and metastatic lymph nodes may accelerate the invasion and metastasis of cholangiocarcinoma through inducing EMT, microRNA-21 might predict the prognosis of patients.
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