肠道微生物组在肺癌进展中发挥关键作用。然而，肠道菌群及其代谢物参与肺癌过程的具体机制尚不清楚。我们收集了52例肺癌患者和29名健康对照个体的粪便样本，并对其进行了16S rRNA基因扩增测序和非靶向气相/液相色谱质谱代谢组学分析。然后对可能在疾病中发挥重要作用的菌群、代谢物和潜在信号通路进行了筛选。健康对照组中的Firmicutes、Clostridia、Bacteroidacea、Bacteroides和Lachnospira丰度较高。相反，Ruminococcus gnavus (R.gnavus)在肺癌患者中显著上调。在这方面，鳞状细胞癌 (SCC) 组的微生物组相对丰度较高的有Proteobacteria、Gammaproteobacteria、Bacteroides和Enterobacteriaceae，而腺癌 (ADC) 组的微生物组中Fusicatenibacter和Roseburia的丰度较高。代谢组学分析显示，肺癌患者的粪便代谢物包括奎尼酸、3-羟基苯甲酸、1-甲基逆咪唑脲、3,4-二羟基肉桂酸和3,4-二羟基苯乙酸发生了显著改变。此外，肺癌的R.gnavus和Fusicatenibacter与多个代谢物水平相关。我们的研究为全面系统地评估肠道微生物组及其代谢产物在肺癌中的贡献提供了必要的指导，对于了解肺癌的发病机制并进行更好的早期预防和靶向干预具有重要潜力。版权所有 © 2023 Lu, Xiong, Zheng, Yu, Xiao and Xie。

The gut micro-biome plays a pivotal role in the progression of lung cancer. However, the specific mechanisms by which the intestinal microbiota and its metabolites are involved in the lung cancer process remain unclear.Stool samples from 52 patients with lung cancer and 29 healthy control individuals were collected and subjected to 16S rRNA gene amplification sequencing and non-targeted gas/liquid chromatography-mass spectrometry metabolomics analysis. Then microbiota, metabolites and potential signaling pathways that may play an important role in the disease were filtered.Firmicutes, Clostridia, Bacteroidacea, Bacteroides, and Lachnospira showed a greater abundance in healthy controls. In contrast, the Ruminococcus gnavus(R.gnavus) was significantly upregulated in lung cancer patients. In this respect, the micro-biome of the squamous cell carcinoma(SCC)group demonstrated a relatively higher abundance of Proteobacteria, Gammaproteobacteria, Bacteroides,and Enterobacteriaceae, as well as higher abundances of Fusicatenibacter and Roseburia in adenocarcinoma(ADC) group. Metabolomic analysis showed significant alterations in fecal metabolites including including quinic acid, 3-hydroxybenzoic acid,1-methylhydantoin,3,4-dihydroxydrocinnamic acid and 3,4-dihydroxybenzeneacetic acid were significantly altered in lung cancer patients. Additionally, the R.gnavus and Fusicatenibacter of lung cancer were associated with multiple metabolite levels.Our study provides essential guidance for a fundamental systematic and multilevel assessment of the contribution of gut micro-biome and their metabolites in lung cancer,which has great potential for understanding the pathogenesis of lung cancer and for better early prevention and targeted interventions.Copyright © 2023 Lu, Xiong, Zheng, Yu, Xiao and Xie.