放射治疗联合阻断PD-1/PD-L1通路肿瘤免疫治疗的新进展

恶性肿瘤发生、发展的每一个阶段均与免疫系统密切相关,而肿瘤细胞也常常利用程序性死亡蛋白-1通路等免疫调节检查点成功逃避免疫系统的攻击。目前,一些靶向于程序性死亡蛋白-1通路的免疫治疗药物已进入临床。过去,放疗一度被认为是一种局部性的免疫抑制性肿瘤治疗手段。最近,越来越多的证据表明,放疗更可能是一种全身性的免疫刺激性肿瘤治疗手段,因而靶向于程序性死亡蛋白-1通路的免疫治疗与放疗之间可能会存在协同作用从而产生强大的抗肿瘤疗效。本文旨在探讨目前放疗联合PD-1/PD-L1通路肿瘤免疫治疗领域内取得的新进展、面临的挑战以及未来的发展方向。

Recent progress in the combination treatment of radiotherapy and PD-1/PD-L1 signaling blockade immunotherapy

Every stage of tumor initiation and development closely relates to immune regulation as tumor cells tend to evade attacks from immune system by employing the programmed death 1 (PD-1)/programmed death-ligand 1 (PD-L1) interaction. Therefore, targeting the PD-1/PD-L1 pathway has become an attractive approach for cancer immunotherapy. Radiotherapy has long been considered a local tumor treatment modality and it is immune-inhibitory. However, accumulated evidence has shown that radiotherapy might enhance immune function by eliminating the tumor mass and has become a systemic tumor treatment modality. These observations indicate a strong rationale that the radiotherapy and anti-PD-1 and anti-PD-L1 immunotherapy may work synergistically to provide a powerful anti-tumor effect. This review discusses current progresses, challenges and perspectives of this novel combination treatment modality.