PDCD1 and lung cancer: We found that the expression level of PD-L1 in lung cancer tissue was significantly higher than that in healthy lung tissue, while endurance exercise tended to increase PD-L1 expression in lung cancer tissue (P=0.06) (Figure 3C, G), suggesting that endurance exercise combined with targeting PD-L1/PD-1 axis may be an effective measure to treat lung cancer mice.