Department of Epidemiology, College of Public Health and Health Professions and College of Medicine, University of Florida, Gainesville, USA.
Emerging Pathogens Institute, University of Florida, Gainesville, USA.
Cancer Causes Control. 2020 Nov;31(11):1027-1038. doi: 10.1007/s10552-020-01338-5. Epub 2020 Aug 25.
Previous reports suggest that a complex microbiome exists within the female human breast that might contribute to breast cancer etiology. The purpose of this pilot study was to assess the variation in microbiota composition by breast side (left versus right) within individual women and compare the microbiota of normal and breast tumor tissue between women. We aimed to determine whether microbiota composition differs between these groups and whether certain bacterial taxa may be associated with breast tumors.
Bilateral normal breast tissue samples (n = 36) were collected from ten women who received routine mammoplasty procedures. Archived breast tumor samples (n = 10) were obtained from a biorepository. DNA was extracted, amplified, and sequenced. Microbiota data were analyzed using QIIME and RStudio.
The most abundant phyla in both tumor and normal tissues were Bacteroidetes, Firmicutes, Proteobacteria, and Actinobacteria. There were statistically significant differences in the relative abundance of various bacterial taxa between groups. Alpha diversity (Simpson's index) was significantly higher in normal compared to tumor samples (0.968 vs. 0.957, p = 0.022). Based on unweighted UniFrac measures, breast tumor samples clustered distinctly from normal samples (R = 0.130; p = 0.01). Microbiota composition in normal samples clustered within women (R = 0.394; p = 0.01) and by breast side (left or right) within a woman (R = 0.189; p = 0.03).
Significant differences in diversity between tumor and normal tissue and in composition between women and between breasts of the same woman were identified. These results warrant further research to investigate the relationship between microbiota and breast cancer.
先前的报告表明，女性乳房内存在复杂的微生物群，可能有助于乳腺癌的发病机制。本研究旨在评估女性个体内左右乳房侧间微生物群落组成的差异，并比较女性正常和乳房肿瘤组织之间的微生物群落。我们旨在确定这些组之间的微生物群落组成是否存在差异，以及某些细菌类群是否与乳腺癌相关。
从接受常规乳房成形术的十位女性中收集双侧正常乳房组织样本（n=36）。从生物库中获得存档的乳房肿瘤样本（n=10）。提取、扩增和测序 DNA。使用 QIIME 和 RStudio 分析微生物组数据。
肿瘤和正常组织中最丰富的菌门是厚壁菌门、拟杆菌门、变形菌门和放线菌门。各组之间的各种细菌类群的相对丰度存在统计学差异。与肿瘤样本相比，正常样本的 alpha 多样性（辛普森指数）显著更高（0.968 与 0.957，p=0.022）。基于非加权 UniFrac 测量，乳房肿瘤样本与正常样本明显聚类（R=0.130；p=0.01）。正常样本中的微生物群落在女性内聚类（R=0.394；p=0.01），在女性内左右乳房侧间聚类（R=0.189；p=0.03）。
肿瘤和正常组织之间的多样性和女性之间以及同一女性乳房之间的组成存在显著差异。这些结果需要进一步研究，以调查微生物群与乳腺癌之间的关系。
