The opposing roles of innate and adaptive immune cells in suppressing or supporting cancer initiation, progression, metastasis and response to therapy has been long debated. The mechanisms by which different monocyte and T cell subtypes affect and modulate cancer have been extensively studied. However, the role of B cells and their subtypes have remained elusive, perhaps partially due to their heterogeneity and range of actions. B cells can produce a variety of cytokines and present tumor-derived antigens to T cells in combination with co-stimulatory or inhibitory ligands based on their phenotype. Unlike most T cells, B cells can be activated by innate immune stimuli, such as endotoxin. Furthermore, the isotype and specificity of the antibodies produced by plasma cells regulate distinct immune responses, including opsonization, antibody-mediated cellular cytotoxicity (ADCC) and complement activation. B cells are shaped by the tumor environment (TME), with the capability to regulate the TME in return. In this review, we will describe the mechanisms of B cell action, including cytokine production, antigen presentation, ADCC, opsonization, complement activation and how they affect tumor development and response to immunotherapy. We will also discuss how B cell fate within the TME is affected by tumor stroma, microbiome and metabolism.

先天性免疫细胞和适应性免疫细胞在抑制或支持癌症发生、进展、转移和治疗反应方面的相反作用一直存在争议。不同单核细胞和 T 细胞亚型影响和调节癌症的机制已得到广泛研究。然而，B 细胞及其亚型的作用仍然难以捉摸，部分原因可能是它们的异质性和作用范围。B 细胞可以产生多种细胞因子，并根据其表型结合共刺激或抑制配体将肿瘤来源的抗原呈递给 T 细胞。与大多数 T 细胞不同，B 细胞可以被先天免疫刺激（例如内毒素）激活。此外，浆细胞产生的抗体的同种型和特异性调节不同的免疫反应，包括调理作用、抗体介导的细胞毒性（ADCC）和补体激活。B 细胞由肿瘤环境 (TME) 塑造，并且能够反过来调节 TME。在这篇综述中，我们将描述 B 细胞的作用机制，包括细胞因子产生、抗原呈递、ADCC、调理作用、补体激活以及它们如何影响肿瘤的发展和对免疫治疗的反应。我们还将讨论肿瘤基质、微生物组和代谢如何影响 TME 内的 B 细胞命运。