After treatment with 5-Aza, the PD1 expression was significantly increased in eight lung cancer cell lines (H2170, H1299, H226, H157, H23, A549, H1650, and H1975), and PD-L1 expression was significantly enhanced in nine lung cancer cell lines (H2170, H1299, H226, H157, H2030, COLO677, A549, H1650, and H1975) (Supplementary Figure S1). This evidence concerns the gene PDCD1 and lung cancer.