Expression of CD44 in pancreatic cancer and its significance.

BACKGROUND CD44 is a potentially interesting prognostic marker and therapeutic target in pancreatic cancer. The expression of CD44 has been reported to correlate with poor prognosis of pancreatic cancer in most literatures. The purpose of this study is to investigate the roles of CD44 in pancreatic caner, and their correlation with the prognosis of pancreatic cancer patients. METHODS 67 pancreatic cancer samples were collected in Xinhua hospital affiliated to Shanghai Jiaotong University dating from Jan 2010 to Dec 2012. Immunohistochemistry was applied to test the expression of CD44 in pancreatic cancer. The clinical data of the patients were collected including their gender, age, the histology and location, lymph node metastasis and so on. The correlation between the CD44 expression and the clinicopathological factors of patients with pancreatic cancer was analyzed by the software SPSS 13.0. We devise and synthesis of effectively interference of shRNA sequence of CD44, which was transefected to the pancreatic cancer cells PANC-1. Colony formation assay, cell migration assays and western blot were performed. RESULTS The positive rates of CD44 expression in pancreatic samples were 73.1% (49/67). Univariate analysis showed that there were a significant differences between the CD44 expression and the pancreatic cancer' T staging, TNM staging, lymph node metastasis, the differentiation degree, tumor location (P < 0.05). The Cox proportional hazards model showed that differentiation, CD44 expression and nerve invasion were independent prognostic factors. Knockdown of CD44 expression in pancreatic cancer cells led to decreased cellular proliferation and migration ability, accompanied by downregulation of p-ERK and p-AKT. CONCLUSION CD44 were related to the distant metastasis and aggressive malignant behaviors of pancreatic cancer. CD44 may regulate tumorigenesis and cancer metastasis partially via PI3K/AKT or MAPK/ERK regulatory pathway.