Original Article


Level of circulating PD-L1 expression in patients with advanced gastric cancer and its clinical implications

Zhixue Zheng, Zhaode Bu, Xijuan Liu, Lianhai Zhang, Ziyu Li, Aiwen Wu, Xiaojiang Wu, Xiaojing Cheng, Xiaofang Xing, Hong Du, Xiaohong Wang, Ying Hu, Jiafu Ji

Abstract

Objective: The programmed cell death-1 receptor/programmed cell death-1 ligand (PD-1/PD-L1) pathway plays a crucial role in tumor evasion from host immunity. This study was designed to evaluate the association between circulating PD-L1 expression and prognosis in patients with advanced gastric cancer.
Methods: Totally 80 advanced gastric cancer patients and 40 health controls from Beijing Cancer Hospital were enrolled in the present study. Circulating PD-L1 expression was tested by enzyme-linked immunosorbent assay (ELISA). The associations between the expression level of PD-L1 and clinicopathological features and prognosis were analyzed statistically.
Results: Expression of PD-L1 in advanced gastric cancer patients was significantly up-regulated compared with health people (P=0.006). The expression of PD-L1 was significantly correlated with differentiation and lymph node metastasis (P=0.026 and P=0.041, respectively). Although we didn’t find significant difference in all advanced gastric cancer patients with different PD-L1 expression, the adenocarcinoma patients with higher up-regulated PD-L1 expression had much better prognosis than low expression patients (65.6% vs. 44.7%, P=0.028).
Conclusions: PD-L1 was elevated in advance gastric cancer patients and may play an important role in tumor immune evasion and patients prognosis.