The mechanism of de novo expression of programmed cell death-ligand 1 in squamous cell carcinoma of the lung

Immune checkpoint mechanisms such as the programmed cell death-ligand 1-programmed cell death 1 (PD‑L1-PD‑1) axis are utilized by tumor cells to evade the cytotoxicity of effector immune cells. However, environmental factors responsible for the expression of PD‑L1 on tumor cells remain to be fully elucidated. We hypothesized that an immunological interaction with tumor-infiltrating CD8+ lymphocytes (CD8+ TILs) would contribute to PD‑L1...