The expression and prognostic significance of DKK3 in gastric cancer

Abstract

Objective To study the expression of DKK3 protein and mRNA levels in gastric cancer and its correlation with the clinical prognosis of gastric cancer. Methods The expression of DKK3 protein in 158 gastric cancer specimens and paired adjacent non-cancerous tissues were detected by immunohistochemistry.The relationship between the protein expression and clinicopathological features was analyzed.Immunoblotting and real time quantitative PCR were used to examine the expression of DKK3 protein and mRNA levels in 76 paired fresh gastric cancer and adjacent non-cancerous tissues. Results The expression of DKK3 in gastric cancer tissues was lower than that in adjacent non-cancerous tissues (40.5% vs. 55.1%, χ2=41.442, P=0.000). DKK3 protein and mRNA levels in 76 cases were lower than that in adjacent non-cancerous tissues (1.096±1.110 vs. 3.476±1.119, t=3.332, P=0.017; 1.136±1.013 vs. 3.314±1.105, t=2.673, P=0.022). There were close correlations between DKK3 expression and depth of tumor invasion (P=0.006), TNM stage (P=0.005) and lymphatic metastasis (P=0.009). The expression of DKK3 in gastric cancer was positively related with overall survival rate(47.4% vs. 28.0%, P=0.011), as an independent prognosis predictor (P=0.016). Conclusions DKK3 is an independent prognostic factor of gastric cancer, its decreased expression is significantly related with shortened survival time of gastric cancer patients. Key words: Stomach neoplasms; Pathology, clinical; Prognosis; DKK3