Intralymph Node Expressions of A2AR and PD-L1 Were Associated with Metastasis and a Poor Prognosis in Gastric Cancer

Abstract

Lymph node metastasis is an independent risk factor for survival of gastric cancer, but the underlying mechanism remains unclear. Adenosine (ADO) plays an immune regulation role through binding to adenosine receptors (ARs), especially A2AR. PD-L1 plays a key role in the immune escape of tumor. However, the expression of these two indicators in lymph nodes of gastric cancer has been rarely studied. Lymph node samples of 95 gastric cancer patients, including metastatic lymph nodes and matched non-metastatic lymph nodes were collected. Expression of A2AR and PD-L1 were detected with immunohistochemistry. The relationships among their expression with clinicopathological factors and prognostic parameters were analyzed as well. The expressions of A2AR and PDL-1 were both higher in metastatic lymph node than matched non-metastatic lymph node. The expression of A2AR in metastatic lymph nodes of gastric cancer was positively correlated with PD-L1. Positive expressions of A2AR and PDL-1 were associated with tumor N stage and prognostic parameters. There was no significant relationship with other clinicopathological characteristics. Our obtained data suggested that the high expressions of A2AR and PD-L1 were associated with the lymph node metastasis and a poor prognosis in gastric cancer, which may be a potential diagnostic and a therapeutic target for gastric cancer.