Abstract: Objective To observe the effects of pancreatic cancer cell soluble secretions on lipid metabolism. Methods The conditioned media of pancreatic cancer cells were derived from serum-free media culturing pancreatic cancer cells for 24 h. The whole study included 2 sub-studies. In the first one, 37 BALB/c mice were randomly divided into control group (n=14)，Panc-1 group (n=10), MiaPaCa-2 group (n=6) and BxPC-3 group (n=7). The normal DMEM and conditioned media of 3 pancreatic cancer cell lines (Panc-1, MiaPaCa-2 and BxPC-3) were injected into mice in the corresponding group. The mice in each group received subcutaneous injection twice a day for 7 days. Body weight and food intake of each mouse were recorded. Blood levels of glucose, triglyceride and hepatic glycogen content were detected. Plasma insulin level was detected by ELISA. Inguinal fat pad and epididymal fat pad were weighed, and the expression levels of ATGL were detected by Western blot assay. The second sub-study consisted of 30 mice and were divided into 3 groups, control group (n=10), 1/2 M group (n=10) and M group (n=10). The normal DMEM and the different doses of MiaPaCa-2 cell conditioned media were injected into the corresponding groups of mice. Results In the first sub-study, the initial intake and body weight of mice decreased, and then recovered and tended to balance. Compared with the control group, the levels of plasma insulin and blood glucose increased, hepatic glycogen and triglyceride contents decreased, and the weight of BAT and WAT increased in MiaPaCa-2 group and BxPC-3 group (P＜0.05), but only triglyceride contents decreased in Panc-1 group (P＜0.05). The expression level of ATGL in adipose tissue was decreased in three pancreatic cancer cell media injection groups (P＜0.05). In the M group of second experiment, plasma insulin and glucose increased (P＜0.05), hepatic glycogen and triglyceride decreased (P＜0.05), BAT and WAT weights increased (P＜0.05), ATGL expression decreased (P＜0.05), only insulin level and fat depot weights increased in 1/2 M group (P＜0.05). Conclusion Injection of pancreatic cancer cell conditioned medium into mice can cause the dysregulation of lipid metabolism in vivo. In addition, the decreased insulin sensitivity, increased fat storage and impaired lipolysis are observed.

Key words: pancreatic neoplasms, cachexia, lipid metabolism, insulin resistant, humoral regulation