Cancer immunotherapy, which reactivates weakened immune cells of cancer patients, has yielded great success in recent years. Among immunotherapeutic agents, immune checkpoint inhibitors have been of particular interest and have gained approval by the FDA for treatment of cancers. Immune checkpoint blockade through targeting programmed cell death protein-1 (PD-1) has demonstrated promising antitumor effects in cancer immunotherapy of many different solid and hematologic malignancies. However, despite promising results, a favorable response is observed only in a fraction of patients, and there is still lack of a single therapy modality with curative ability. In this paper, we review the current and future perspectives of PD-1/L1 blockade in cancer immunotherapy, with a particular focus on predictive biomarkers of response to therapy. We also discuss the adverse events associated with PD-1/L1/2 inhibitors, ranging from severe life-threatening conditions such as autoimmune myocarditis to mild and moderate reactions such as skin rashes, and explore the potential strategies for improving the efficacy of immunotherapy with PD-1/L1 checkpoint inhibitors.

中文翻译：

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PD-1/PDL-1 阻断在癌症免疫治疗中的当前和未来前景

癌症免疫疗法可以重新激活癌症患者虚弱的免疫细胞，近年来取得了巨大成功。在免疫治疗药物中，免疫检查点抑制剂特别受关注，并已获得 FDA 批准用于治疗癌症。通过靶向程序性细胞死亡蛋白-1 (PD-1) 进行的免疫检查点阻断已在许多不同实体和血液恶性肿瘤的癌症免疫治疗中显示出有希望的抗肿瘤作用。然而，尽管结果令人鼓舞，但仅在一小部分患者中观察到了良好的反应，并且仍然缺乏具有治愈能力的单一治疗方式。在本文中，我们回顾了 PD-1/L1 阻断在癌症免疫治疗中的当前和未来前景，特别关注对治疗反应的预测性生物标志物。