A2aR on lung adenocarcinoma cells: A novel target for cancer therapy via recruiting and regulating tumor-associated macrophages

Adenosine 2a receptor (A2aR), a typical GPCR with a high affinity for adenosine, is widely expressed on immune cells, inhibiting anti-tumor immune response accordingly. Here, we identify that A2aR is specifically expressed on tumor cells from lung adenocarcinoma (LUAD) patients, closely related to their prognosis and positively correlated with tumor-associated macrophages (TAMs) infiltration. We hypothesize that blocking A2aR on LUAD cells will inhibit the role of TAMs and control tumor growth. Constructing models of TAMs and LUAD mice, we find that A2aR highly expressed on LUAD cells promotes the secretion of chemokines and polarizing factors through activating PI3K/AKT/NF-& kappa;B pathway, thereby promoting the migration and invasion of TAMs. Func-tionally, blocking A2aR significantly suppresses TAMs infiltration and attenuates tumor burden in LUAD mice. Notably, the M2 polarization of TAMs can also be prevented by inhibiting A2aR in vitro. Together, our studies demonstrate that A2aR on LUAD cells drives TAMs migration and polarization, and blockade of A2aR may support a novel and potent therapeutic option for LUAD.