Besides, higher levels of GZMA and XCL1 were observed in the NK cells from the PD-1+SMI group compared with those in the remaining groups, suggesting that the PD-1 inhibitor combined with SMI induced cytotoxic NK cells to infiltrate the NSCLC tumor and may recruit DCs into the tumor via NK cells, thus improving the antitumor efficacy. Here, PDCD1 is linked to non-small cell lung carcinoma.