Ezrin-radixin-moesin-binding phosphoprotein 50 (EBP50) is a putative tumor suppressor that is correlated with many human cancers. However, the function of EBP50 in pancreatic cancer (PC) has not been described. In this paper, the EBP50 expression level in PC tissues was characterized. In vitro, the effects of EBP50 down-regulation by siRNA in PC-2 and MiaPaCa-2 cells were evaluated. In addition, possible mechanisms that mediate the influence of EBP50 were examined. Our results show that the EBP50 expression pattern changes during transformation as there is a loss of the normal apical membrane distribution and an ectopic cytoplasmic over-expression of EBP50; furthermore, the EBP50 expression level is subsequently decreased during malignant progression. Down-regulation of EBP50 promoted cancer cell proliferation, increased the colony-forming ability of cells and accelerated the G1-to-S progression. Additionally, the loss of EBP50 accentuated β-catenin activity, increased cyclin E and phosphorylated Rb expression, and attenuated p27 expression compared to control cells. Our results suggest that EBP50 may function as a potential tumor suppressor.

Ezrin-radixin-moesin (ERM)-binding phosphoprotein 50 (EBP50) has previously been demonstrated to be associated with the malignant transformation of numerous types of human cancer. The aim of the present study was to investigate the effect of EBP50 overexpression on pancreatic cancer and the underlying mechanism. Reverse transcription-quantitative polymerase chain reaction was used to detect the expression of EBP50 in human pancreatic cancer tissue specimens. Furthermore, pBK-CMV-HA-EBP50 and the pBK-CMV-HA vectors were transfected into pancreatic cancer cells and the effect of EBP50 upregulation on the proliferation and invasion of the cells was investigated. In addition, the effect of EBP50 overexpression on β-catenin and E-cadherin expression was evaluated. The results revealed that overexpression of EBP50 suppressed cell growth and invasion in two human pancreatic cancer cell lines. Overexpression of EBP50 also suppressed β-catenin expression and increased E-cadherin expression. Thus, the present study demonstrated that EBP50 inhibits pancreatic cancer cell growth and invasion through targeting the β-catenin/E-cadherin pathway. The results suggest that EBP50 may function as a potential tumor suppressor and thus may serve as a potential therapeutic target.