PD-1和PD-L1在肿瘤免疫逃逸中的作用机制及临床意义

随着人们对肿瘤免疫微环境的深入研究，发现肿瘤细胞的免疫逃逸是造成肿瘤进展的关键原因，其分子机制也成为肿瘤免疫治疗研究的重点问题之一。近年研究表明程序性死亡受体-1（programmed death receptor-1，PD-1）与程序性死亡配体-1（programmed death ligand-1，PD-L1）与肿瘤发生、发展有密切联系。其中，PD-1是T细胞介导免疫反应中的重要抑制性免疫检查点，肿瘤细胞通过表达PD-L1，与肿瘤浸润淋巴细胞的PD-1结合，诱导淋巴细胞的凋亡，从而抵抗淋巴细胞的杀伤作用，最终造成肿瘤发生免疫逃逸。本文对PD-1和PD-L1在肿瘤免疫逃逸中的作用机制及在肿瘤治疗中的临床意义作一综述。

Clinical significance and mechanism of PD-1 and PD-L1 in cancer immune escape

With the further study of tumor immune microenvironment，it is found that immune escape of tumor cells is the key cause of tumor progression，and its molecular mechanisms have become the one of focused question regarding tumor immunotherapy research.Recent studies demonstrated that programmed death receptor-1(PD-1) and programmed death ligand-1(PD-L1) has closely correlation with occurrence and progression of tumor.Thereinto，PD-1 is an important check-point for the inhibit immunity in the immune response induced by T cells.The expression of PD-L1 by tumor cells is integrated with PD-1 of lymphocytes infiltrated by tumor，lead to the apoptosis of lymphocytes，so as to resist the lethal effect of lymphocytes，which cause the cancer immune escape finally.This review concludes the mechanisms of PD-1 and PD-L1 in cancer immune escape and clinical significance of PD-1 and PD-L1 in the tumor treatment.