Thus, the interaction between ICOS and ICOSL is a central mechanism in tumor immune evasion, although there are still other cancer types with higher levels of ICOS expression on activated effector TILs other than Tregs, in which ICOS expression was correlated with improved survival, such as in colorectal cancer (143) and lung adenocarcinoma (144). The gene discussed is ICOS; the disease is lung adenocarcinoma.