PDCD1 and cancer: In addition, the level of SIRPα was positively correlated to these cancer‐related immune suppressive checkpoints, including PD‐1 (pdcd1), PD‐L1 (cd274), CTLA‐4 (ctla‐4) and TIM‐3 (havcr2) in patients with LUAD and LUSC (Figure S6c).