Department of Preventive Medicine, Seoul National University College of Medicine, Seoul, 03080, South Korea.
Integrated Major in Innovative Medical Science, Seoul National University College of Medicine, Seoul, 03080, South Korea.
BMC Microbiol. 2023 Jan 28;23(1):33. doi: 10.1186/s12866-023-02771-7.
Differences in the composition and diversity of the gut microbial communities among individuals are influenced by environmental factors. However, there is limited research on factors affecting microbiome variation in colorectal cancer patients, who display lower inter-individual variations than that of healthy individuals. In this study, we examined the association between modifiable factors and the microbiome variation in colorectal cancer patients.
A total of 331 colorectal cancer patients who underwent resection surgery at the Department of Surgery, Seoul National University Hospital between October 2017 and August 2019 were included. Fecal samples from colorectal cancer patients were collected prior to the surgery. Variations in the gut microbiome among patients with different lifestyles and metabolic diseases were examined through the network analysis of inter-connected microbial abundance, the assessment of the Anna Karenina principle effect for microbial stochasticity, and the identification of the enriched bacteria using linear discrimination analysis effect size. Associations of dietary diversity with microbiome variation were investigated using the Procrustes analysis.
We found stronger network connectivity of microbial communities in non-smokers, non-drinkers, obese individuals, hypertensive subjects, and individuals without diabetes than in their counterparts. The Anna Karenina principle effect was found for history of smoking, alcohol consumption, and diabetes (with significantly greater intra-sample similarity index), whereas obesity and hypertension showed the anti-Anna Karenina principle effect (with significantly lower intra-sample similarity index). We found certain bacterial taxa to be significantly enriched in patients of different categories of lifestyles and metabolic diseases using linear discrimination analysis. Diversity of food and nutrient intake did not shape the microbial diversity between individuals (p>0.05).
Our findings suggested an immune dysregulation and a reduced ability of the host and its microbiome in regulating the community composition. History of smoking, alcohol consumption, and diabetes were shown to affect partial individuals in shifting new microbial communities, whereas obesity and history of hypertension appeared to affect majority of individuals and shifted to drastic reductions in microbial compositions. Understanding the contribution of modifiable factors to microbial stochasticity may provide insights into how the microbiome regulates effects of these factors on the health outcomes of colorectal cancer patients.
个体肠道微生物群落的组成和多样性差异受环境因素影响。然而，关于影响结直肠癌患者微生物组变化的因素的研究有限，这些患者的个体间变化比健康个体小。本研究旨在探讨可改变因素与结直肠癌患者微生物组变化之间的关系。
共纳入 2017 年 10 月至 2019 年 8 月在首尔国立大学医院外科接受手术的 331 例结直肠癌患者。在手术前收集结直肠癌患者的粪便样本。通过网络分析相互关联的微生物丰度、评估微生物随机性的安娜·卡列尼娜原则效应以及使用线性判别分析效应大小鉴定富集细菌，来检查不同生活方式和代谢疾病患者的肠道微生物组变化。使用 Procrustes 分析研究饮食多样性与微生物组变化之间的关联。
我们发现，不吸烟、不饮酒、肥胖、高血压和无糖尿病患者的微生物群落网络连接性更强。吸烟史、饮酒史和糖尿病史存在安娜·卡列尼娜原则效应（具有显著较高的样本内相似性指数），而肥胖和高血压表现出反安娜·卡列尼娜原则效应（具有显著较低的样本内相似性指数）。使用线性判别分析，我们发现某些细菌类群在不同生活方式和代谢疾病类别的患者中显著富集。食物和营养素摄入的多样性并没有塑造个体之间的微生物多样性（p＞0.05）。
我们的研究结果表明，免疫失调和宿主及其微生物组调节群落组成的能力降低。吸烟史、饮酒史和糖尿病史被证明会影响部分个体形成新的微生物群落，而肥胖和高血压史似乎会影响大多数个体，并导致微生物组成急剧减少。了解可改变因素对微生物随机性的贡献可能有助于了解微生物组如何调节这些因素对结直肠癌患者健康结果的影响。
