ABSTRACT
Programmed death ligand-1 (PD-L1) is highly expressed on most tumor cells,and it interacts with programmed death-1 (PD-1) on the surface of immune cells,which mainly inhibits T cell proliferation and plays an important role in tumor immune escape.The studies find that PD-1/PD-L1 pathway can promote tumor cell glycolysis and epithelial-mesenchymal transition,and can induce PD-L1 expression on macrophages and enhance immunosuppression in tumor microenvironment.Therefore,PD-1/PD-L1 is considered to be an important immunoassay point,and a series of anti-PD-1 and PD-L1 antibodies,such as pembrolizumab,nivolumab,atezolizumab,durvalumab and avelumab,have clinically shown good effects.Further understanding of its mechanism may provide new ideas for the treatment of malignant tumors such as lung tumors.