CD8A and neoplasm: While adaptive immune cells such as NK cells and CD8+ T lymphocytes may inhibit tumor growth by promoting anti-tumor immunity (13), several studies have demonstrated that innate immune cells, such as macrophages, mast cells, and neutrophils are capable of forming a chronic inflammatory environment that promotes epithelial-mesenchymal transition (EMT) and neovascularization, which are essential processes for tumor progression (7, 14).