Myeloid cells are the most abundant immune components of the tumour microenvironment, where they have a variety of functions, ranging from immunosuppressive to immunostimulatory roles. The myeloid cell compartment comprises many different cell types, including monocytes, macrophages, dendritic cells and granulocytes, that are highly plastic and can differentiate into diverse phenotypes depending on cues received from their microenvironment. In the past few decades, we have gained a better appreciation of the complexity of myeloid cell subsets and how they are involved in tumour progression and resistance to cancer therapies, including immunotherapy. In this Review, we highlight key features of monocyte and macrophage biology that are being explored as potential targets for cancer therapies and what aspects of myeloid cells need a deeper understanding to identify rational combinatorial strategies to improve clinical outcomes of patients with cancer. We discuss therapies that aim to modulate the functional activities of myeloid cell populations, impacting their recruitment, survival and activity in the tumour microenvironment, acting at the level of cell surface receptors, signalling pathways, epigenetic machinery and metabolic regulators. We also describe advances in the development of genetically engineered myeloid cells for cancer therapy.

骨髓细胞是肿瘤微环境中最丰富的免疫成分，它们具有多种功能，从免疫抑制到免疫刺激。骨髓细胞区室包含许多不同的细胞类型，包括单核细胞、巨噬细胞、树突状细胞和粒细胞，它们具有高度可塑性，可以根据从其微环境中接收到的线索分化成不同的表型。在过去的几十年里，我们对骨髓细胞亚群的复杂性以及它们如何参与肿瘤进展和对癌症疗法（包括免疫疗法）的耐药性有了更好的认识。在这篇评论中，我们强调了单核细胞和巨噬细胞生物学的关键特征，这些特征正在作为癌症治疗的潜在靶点进行探索，以及骨髓细胞的哪些方面需要更深入地了解以确定合理的组合策略以改善癌症患者的临床结果。我们讨论旨在调节骨髓细胞群功能活动的疗法，影响它们在肿瘤微环境中的募集、存活和活动，作用于细胞表面受体、信号通路、表观遗传机制和代谢调节因子的水平。我们还介绍了用于癌症治疗的基因工程骨髓细胞的开发进展。我们讨论旨在调节骨髓细胞群功能活动的疗法，影响它们在肿瘤微环境中的募集、存活和活动，作用于细胞表面受体、信号通路、表观遗传机制和代谢调节因子的水平。我们还介绍了用于癌症治疗的基因工程骨髓细胞的开发进展。我们讨论旨在调节骨髓细胞群功能活动的疗法，影响它们在肿瘤微环境中的募集、存活和活动，作用于细胞表面受体、信号通路、表观遗传机制和代谢调节因子的水平。我们还介绍了用于癌症治疗的基因工程骨髓细胞的开发进展。