Expression of CD44 and prostate stem cell antigen and their prognostic significance in human pancreatic ductal adenocarcinoma

CD44 and prostate stem cell antigen (PSCA) have been investigated as two biomarkers for various cancers. However, either CD44 or PSCA expression alone has limited clinical value. In the present study, the expression of CD44 and PSCA in human pancreatic ductal adenocarcinoma (PDAC) and their values in prognosis were investigated by immunohistochemistry (IHC) and Kaplan-Meier method. The results suggested that CD44 and PSCA were significantly upregulated in pancreatic tumor tissue. No significant association were observed between CD44 expression and PSCA expression (r=0.15, P=0.03). High expression of CD44 was significantly correlated with poor tumor differentiation (P=0.021), and indicated a poor outcome (P=0.003). Expression of PSCA was positively related to tumor size (P=0.027) and nodal metastasis (P=0.030). Co-expression of CD44 and PSCA significantly indicated a poor outcome (P=0.005). Moreover, multivariate survival analysis demonstrated that positive co-expression of CD44 and PSCA was an independent indicator for PDCA prognosis (P=0.040). Therefore, our data indicated that co-staining of CD44 and PSCA should be recommended in PDCA patients for predicting prognosis.