先天效应细胞是带有宿主保护特征和细胞毒性功能的免疫细胞。通过感知组织环境，先天免疫细胞在调节从稳态到炎症的转变以及病理状态的建立中发挥重要作用，包括癌症的发作和发展。肿瘤微环境诱导先天细胞发生分子和功能上的改变，降低它们启动和维持抗肿瘤免疫反应的能力。新兴研究清楚地表明了菌群在调节癌症中的先天细胞功能中的贡献。共生微生物不仅可以直接与肿瘤微环境中的先天细胞互动，还可以通过释放微生物产物从非肿瘤部位发挥免疫调节特征。 菌群可以在黏膜组织中介导先天细胞的启动，并且在它们迁移到非黏膜组织时决定由这些细胞介导的免疫反应的强度，从而影响癌症。最后，一些证据表明，在抗癌治疗期间，菌群在促进先天免疫反应方面发挥了强烈的贡献，从而提高了治疗效果。在这篇综述中，我们考虑了菌群在塑造宿主先天免疫反应在癌症中的作用的当前知识。Copyright © 2023 Elsevier Ltd. All rights reserved.

Innate effector cells are immune cells endowed with host protective features and cytotoxic functions. By sensing the tissue environment, innate cells have an important role in regulating the transition from homeostasis to inflammation and the establishment of pathological states, including the onset and development of cancer. The tumor microenvironment induces molecular and functional modifications in innate cells, dampening their capability to initiate and sustain anti-tumor immune responses. Emerging studies clearly showed a contribution of the microbiota in modulating the functions of innate cells in cancer. Commensal microorganisms can not only directly interact with innate cells in the tumor microenvironment but can also exert immunomodulatory features from non-tumor sites through the release of microbial products. The microbiota can mediate the priming of innate cells at mucosal tissues and determine the strength of immune responses mediated by such cells when they migrate to non-mucosal tissues, having an impact on cancer. Finally, several evidences reported a strong contribution of the microbiota in promoting innate immune responses during anti-cancer therapies leading to enhanced therapeutic efficacy. In this review, we considered the current knowledge on the role of the microbiota in shaping host innate immune responses in cancer.Copyright © 2023 Elsevier Ltd. All rights reserved.