A significant correlation between high TMB and ICI treatment has been observed across various tumors.51 In LUAD, this conclusion is that the high SGO2 cluster has higher TMB and expression levels of 7 immune checkpoints (PDCD1, CD274, PDCD1LG2, CTLA4, LAG3, HAVCR2, and TIGIT), consistent with previous findings, which show lower immune cell infiltration and attenuated anti-tumor responses could promote tumor growth and migration. This evidence concerns the gene PDCD1 and neoplasm.