Impact of CD73 + CD39 + B Cells on Immune Evasion in Pancreatic Cancer

Background/Aim: Cell surface CD39 and CD73 degrade adenosine triphosphate (ATP) into adenosine, promoting immune tolerance in tumor immunity. In this study, we aimed to characterize regulatory B cells (Bregs) and adenosine-producing B cells in pancreatic cancer (PC) and elucidate the underlying mechanisms of immune evasion. Materials and Methods: Ten patients with PC were recruited, then peripheral blood mononuclear cells (PBMCs) were collected pre-neoadjuvant chemotherapy (NAC), post-NAC, and postoperatively. The frequencies of CD73+CD39+ B cells and Bregs were analyzed by flow cytometry. The prognostic significance of CD73 expression in the tumor stroma was evaluated in 106 PC patients through immunohistochemistry (IHC) staining. Results: IHC analysis demonstrated that CD73 was significantly overexpressed in tumor-infiltrating lymphocytes compared with adjacent normal tissues. Furthermore, high CD73 expression was significantly associated with poorer prognosis compared with low CD73 expression. The frequency of CD19+CD73+CD39+ B cells among PBMCs was significantly lower postoperatively compared with pre-NAC and post-NAC. In PC patients, the frequency of CD73+CD39+ B cells correlated with that of IL-10-producing B cells, with a significant decrease in Bregs observed postoperatively. Conclusion: Adenosine-producing immune cells in PC tissues were associated with poor prognosis, whereas CD73+CD39+ B cells decreased during treatment in patients with PC. These findings provide preliminary evidence that adenosine-producing B cells may be associated with clinical outcomes in PC, warranting further investigation in larger cohorts.