P2RX4 and chronic obstructive pulmonary disease: For example, a previous study by our group that mainly analyzed immune cells in the TME showed that patients with NSCLCs have higher concentrations of CD39, P2X4, and P2X7 in bronchoalveolar lavage (BAL) fluid compared to chronic obstructive pulmonary disease (COPD) patients, suggesting a role of purinergic signaling in NSCLC [29].