IL17A and lung cancer: K-ras activated lung cancer cells orchestrate the TME through secreting cytokines IL-6, IL-10, IL-17, TGF-β, and TNF, which can either suppress antitumor T cells directly or stimulate immune cells such as MDSCs, Th17s, M2 macrophages, and Tregs to inhibit Th1/CD8+ T cell function (62, 88, 98, 129), as we have described above.