CD8A and lung cancer: In lung cancer, multiple studies have documented tight associations between tumor/lung microbiota and γδT17 cells, cytotoxic CD8+ T cells, NK cells and myeloid-derived suppressor cells, and have shown that non–small cell lung cancers with distinct immune-cell compositions harbor different gut- and tumor-associated microbiota and display differential responses to ICIs [40,47,59,60,61,62,63,64].