The tumor microenvironment (TME) is a complex ecosystem composed of several cell types, including immune cells, cancer-associated fibroblasts (CAFs), endothelial cells, and extracellular matrix (ECM), which plays a critical role in cancer progression.10 Among the immune cells infiltrating the TME, T cell, especially CD8+ T cell, is a key antitumor immune component. This evidence concerns the gene CD8A and cancer.