PDCD1 and non-small cell lung carcinoma: By blocking the interaction of T-cell surface Programmed cell Death Protein 1 (PD1) with its ligands Programmed cell Death 1 Ligand 1 (PD-L1) and Programmed cell Death 1 Ligand 2 (PD-L2), the inhibition of immune microenvironment can be eliminated, and the ability of T-cells to kill non-small cell lung cancer can be enhanced.8