Objective: To study the effects of intrasplenic injection of IL-12 and/or IL-2 genes on serum levels of IL-2 and IL-12 and T cell activity in induced liver cancer in rats. Methods: Forty-eight rats with diethylnitrosamine induced liver cancer were equally divided into 4 groups: mock-infected group, IL-2 group, IL-12 group and IL-2/IL-12 group. Retroviral vectors encoding IL-2 and/or IL-12 genes were constructed and were used to transfect packaging cell lines PE501 and PA317. The tansfected PE501 and PA317 cells were injected into rat spleen at different time points and the serum levels of IL-2 and IL-12, T cell activity and toxic effect were determined. Results: The serum levels of IL-2 and IL-12 were obviously increased in IL-2 and IL-12 group, respectively, and the increase was even more obvious in IL-2/IL-12 group. Pathological study showed that there was an increase in lymphocytes infiltration of liver tissues in IL-2/IL-12 group. Compared with mock-infected group, T cell activity markedly increased in IL-2 and IL-12 group, and that in IL-2/IL-12 group was even more active. Moreover, the acting time of IL-2/IL-12 was longer than that of IL-2 or IL-12 alone. Conclusion: Direct injection of IL-2 and/or IL-12 genes into spleen can increase the T cell activity. Combined gene therapy with IL-2 and IL-12 is superior to IL-2 or IL-12 gene alone.

Objective To investigate the expression and significance of MRP3 in pancreatic cancer and different tumor cells. Methods MRP3 expression was detected in 30 cases of pancreatic cancer tissues and the adjacent tissues through immunohistochemical method. RT-PCR was used to detect MRP3 mRNA in 7 tumor cell lines and human embryo kidney cell lines 293T. Monoclonal antibody against MRP3 was employed to detect MRP3 protein expression through flow cytometry. Results There was significant difference for MRP3 expression in nucleus between the pancreatic cancer and normal tissues beside the cancer ( P= 0.003 ) while no significant difference was found in cytoplasm (P = 0. 472). MRP3 mRNA expression was found in 3 pancreatic carcinoma cell lines. The positive expression rate of MRP3 protein was relatively high in BxPC-3 and AsPC-1 cells (68. 5% and 33.6% respectively) while it was only 5.4% in PNAC-1. Conclusions The difference of MRP3 expression in pancreatic cancer and normal tissues lies mainly in nucleus. BxPC-3 may serve as cellular models for in vitro studies on multidrug resistance of pancreatic carcinoma.