2020年，乳腺癌是全球最常见的癌症。需要更深入了解促进肿瘤进展、转移发展和治疗抗性的因素。近年来，在乳腺组织中发现了一个不同寻常的微生物群落，在此之前，这个地方被认为是无菌的。本文回顾了口腔厌氧菌核球菌在乳腺癌中的临床和分子相关性。相比健康的组织，乳腺肿瘤组织富含核球菌，并已被证明能够促进小鼠模型中的乳腺肿瘤生长和转移。目前的文献表明，核球菌在组织微环境内调节免疫逃逸和炎症，而这两者是癌症的明确标志。此外，微生物群落，尤其是核球菌，已被证明影响患者对治疗的反应，包括免疫检查点抑制剂。这些研究结果强调了未来需要进一步研究核球菌在乳腺癌发展和治疗中的影响。

Breast cancer was the most commonly diagnosed cancer worldwide in 2020. Greater understanding of the factors which promote tumour progression, metastatic development and therapeutic resistance is needed. In recent years, a distinct microbiome has been detected in the breast, a site previously thought to be sterile. Here, we review the clinical and molecular relevance of the oral anaerobic bacterium Fusobacterium nucleatum in breast cancer. F. nucleatum is enriched in breast tumour tissue compared with matched healthy tissue and has been shown to promote mammary tumour growth and metastatic progression in mouse models. Current literature suggests that F. nucleatum modulates immune escape and inflammation within the tissue microenvironment, two well-defined hallmarks of cancer. Furthermore, the microbiome, and F. nucleatum specifically, has been shown to affect patient response to therapy including immune checkpoint inhibitors. These findings highlight areas of future research needed to better understand the influence of F. nucleatum in the development and treatment of breast cancer.