Peripheral natural killer cell activity is associated with poor clinical outcomes in pancreatic ductal adenocarcinoma

Abstract

Background and Aim We aimed to measure the natural killer (NK) cell activity and pro-inflammatory cytokine levels in the peripheral blood of pancreatic cancer patients and investigate the correlation of NK cell activity and cytokines with cancer status and clinical outcomes. Methods We prospectively enrolled patients who were pathologically diagnosed with pancreatic ductal adenocarcinoma (PDAC) between 2016 and 2017 at a tertiary hospital in Seoul, South Korea. As a control group, healthy participants were enrolled by mobile application recruitment. Results A total of 203 patients were enrolled for this study (PDAC,n = 102; healthy participants,n = 101). The peripheral blood NK cell activity of PDAC patients was significantly lower than that of healthy participants (median level, 95 pg/mLvs2000 pg/mL,P < 0.001), and decreased NK cell activity was correlated to poor clinical outcome in terms of response to chemotherapy, tumor progression, and survival. The pro-inflammatory cytokine interleukin-6 had a strong negative correlation with NK cell activity. Conclusions In pancreatic cancer patients, NK cell activity decreased as cancer progressed, and decreased NK cell activity was associated with poor clinical outcomes.