Correlation between Claudin-18 expression and clinicopathological features and prognosis in patients with gastric cancer

BackgroundTo investigate the correlation between Claudin-18 expression and the clinicopathological features and prognosis of gastric cancer.MethodsA total of 63 patients who underwent gastric cancer surgery from December 2012 to June 2013 were recruited as the research participants. The clinicopathological data and prognostic information of the participants were collected, and expression levels of Claudin-18 in gastric cancer and adjacent tissues were detected by immunohistochemical (IHC) staining. The correlation between Claudin-18 expression and clinicopathological features of gastric cancer patients was analyzed. The Cox regression model was used to analyze the risk factors associated with the prognosis of gastric cancer patients.ResultsThe expression of Claudin-18 was positive in 35 (55.6%) of the participants’ gastric cancer tissues, which was significantly lower than that in the adjacent tissues (51 tissues/81.0%), and the difference was statistically significant (P=0.002). In addition, the IHC staining score of Claudin-18 expression in gastric cancer tissues (1.49±1.69), was significantly lower than that in the adjacent tissues (4.61±1.81), and the difference was statistically significant (P=0.016), The incidence of nerve invasion in patients with low expression of Claudin-18 was significantly higher than that in patients with high expression of Claudin-18 (P=0.038). In addition, univariate Cox regression analysis showed that nerve invasion, Claudin-18 staining score, tumor size, and positive count of lymph nodes were risk factors associated with the survival of gastric cancer patients. Multivariate Cox regression analysis showed that Claudin-18 staining score and tumor size were independent risk factors associated with the survival of gastric cancer patients. The overall survival (OS) of patients with low Claudin-18 staining score or larger tumor size was significantly reduced.ConclusionsThe low expression of Claudin-18 was closely related to nerve invasion in gastric cancer, which indicated the poor clinical prognosis of gastric cancer patients.