All immune cell types displayed cancer subtype-specific features and functions (Fig. 2b, c, and Supplementary Fig. 2d), and some immunoglobulin genes (IGKC, IGHG1, IGHG3, IGHG4, and IGLC2) were upregulated in each cell type of LUSC tissues compared with LUAD (Fig. 2b and Supplementary Fig. 2e), which were reported to gradually increase in T cells from normal tissues to the tumor and to metastasis in lung cancer.18,19XIST was upregulated in LUAD, which promoted lung cancer cell growth. This evidence concerns the gene IGHG4 and cancer.