Fig. 1.

Cancer gene alteration-induced immunosuppression and T-cell-triggered adaptive resistance. There are two types of immunosuppression: one is caused by various immunosuppressive molecules and cells triggered by activated oncogene signaling pathways mainly resulting from gene alterations in cancer; the other is local adaptive immunosuppression, triggered by tumor-specific T cells in tumors. Cytokines such as IFN-γ produced from activated tumor-specific CTLs induce immunosuppressive molecules such as PD-L1, CD155 and IDO in cancer cells. The main immunosuppression mechanisms vary among patients. Personalized therapies appropriately using small-molecule inhibitors that target oncogenic signals, using specific inhibitors and using specific blocking antibodies can reverse the immunosuppression in cancer patients.