Abstract
Pancreatic cancer is one of the most aggressive cancers. Interleukin-22 (IL-22) is a member of IL-10 cytokine family and primarily produced by Th17 cells which were differentiated from CD4 T cells. CD4 T cells play a central role in regulating the immune response and resisting cancer cells. However, the function of CD4 T cells and Interleukin-22 (IL-22) in the microenvironment of pancreatic cancer remains largely unknown. In the present study, we investigated expression of the IL-22 in tumor cells, CD4 expression in microenvironment of pancreatic cancer and assessed their effects on pathological characteristics and prognosis of pancreatic cancer. To analyze prognostic factors of pancreatic cancer, Kaplan-Meier survival and Cox proportional-hazards regression were applied. Expression of CD4 in pancreatic cancer was associated with pTNM stage (P=0.005). Expression of IL-22 in pancreatic cancer was related not only to pTNM stage (P=0.011) but also to lymph node involvement (P=0.016). Univariate analysis demonstrated that the main prognostic factors of pancreatic cancer are pathological differentiation, expression of low CD4, expression of high IL-22 and the combination of low CD4 expression and high IL-22 expression in pancreatic cancer tissues. Moreover, multivariate analysis clearly showed that pathological differentiation, and the combination of low CD4 expression and high IL-22 expression in pancreatic cancer tissues were independent prognostic factors for overall survival in pancreatic cancer. the present study indicated that CD4 and IL-22 might be used as independent prognostic markers and molecular targets for pancreatic cancer.