The successful treatment of human cancers by immunotherapy has been made possible by breakthroughs in the discovery of immune checkpoint regulators, including CTLA-4 and PD-1/PD-L1. However, the immunosuppressive effect of the tumor microenvironment still represents an important bottleneck that limits the success of immunotherapeutic approaches. The tumor microenvironment influences the metabolic crosstalk between tumor cells and tumor-infiltrating immune cells, creating competition for the utilization of nutrients and promoting immunosuppression. In addition, tumor-derived metabolites regulate the activation and effector function of immune cells through a variety of mechanisms; in turn, the metabolites and other factors secreted by immune cells can also become accomplices to cancer development. Immune-metabolic checkpoint regulation is an emerging concept that is being studied with the aim of restoring the immune response in the tumor microenvironment. In this review, we summarize the metabolic reprogramming of various cell types present in the tumor microenvironment, with a focus on the interaction between the metabolic pathways of these cells and antitumor immunosuppression. We also discuss the main metabolic checkpoints that could provide new means of enhancing antitumor immunotherapy.

免疫检查点调节剂（包括CTLA-4和PD-1 / PD-L1）的发现取得突破，使得通过免疫疗法成功治疗人类癌症成为可能。但是，肿瘤微环境的免疫抑制作用仍然是限制免疫治疗方法成功的重要瓶颈。肿瘤微环境影响肿瘤细胞与浸润肿瘤的免疫细胞之间的代谢串扰，从而为营养利用的竞争和促进免疫抑制创造了竞争。另外，肿瘤衍生的代谢产物通过多种机制调节免疫细胞的激活和效应子功能。反过来，免疫细胞分泌的代谢物和其他因子也可能成为癌症发展的帮凶。免疫代谢检查点调节是一个新兴概念，正在研究中，目的是恢复肿瘤微环境中的免疫反应。在这篇综述中，我们总结了肿瘤微环境中存在的各种细胞类型的代谢重编程，重点是这些细胞的代谢途径与抗肿瘤免疫抑制之间的相互作用。我们还讨论了可以为增强抗肿瘤免疫疗法提供新手段的主要代谢检查点。