Clinical Analysis Of Peripheral Blood MDSCs Of Pancreatic Cancer Patients And Preliminary Research For The Mechanism Of Their Expansion

Objective:To explore the expression levels of the myeloid derived suppressor cells (MDSCs) in pancreatic cancer patients and relationship between expression and clinical significance, and mechanism for their accumulation.Methods:1.Peripheral blood of47healthy controls and39patients with pancreatic cancer as well as17cases of bile duct cancer patients were collected, and then flow cytometry was used to detect surface markers in peripheral blood of CD14+CD11b+HLA DR-MDSCs expression levels.2.Combining with clinical data of clinical stage,we used statistical analysis software to the analyse the role of CD14+CDllb+HLA DR-MDSCs in tumor progression.3.In vitro experiment, four pancreatic cancer cell lines were cocultured with peripheral blood mononuclear cells of control group to induce MDSCs.4.We testd the co-culture solution of the induction culture system, and GM-CSF expression levels and arginase activityof the blood of pancreatic cancer patients.Results:l.In pancreatic cancer patients, peripheral blood CD14+CDllb+HLA DR-MDSCs expression levelswere significantly higher than the control group.2.Peripheral CD14+CDllb+HLA DR-MDSCs expression levels in pancreatic cancer patients were associated with clinical classification.3.Four pancreatic cancer cell lines could successfully induce PBMC to MDSC differentiation in vitro, increasing with the of cancer cell numbers.4. There was no significant change in GM-CSF expression but inhibitory molecule arginase activity.Conclusion:Peripheral blood CD14+CDllb+HLA DR-MDSCs expression in Pancreatic cancer patients was closely related to tumor burden, and arginase activity can be a marker for tumor immunosuppression.