Welham Zoe, Li Jun, Tse Benita, Engel Alexander, Molloy Mark P
Bowel Cancer and Biomarker Laboratory, Kolling Institute, School of Medical Sciences, The University of Sydney, St. Leonards, Australia.
Colorectal Surgical Unit, Royal North Shore Hospital, St. Leonards, Australia.
Gastro Hep Adv. 2025 Apr 28;4(8):100687. doi: 10.1016/j.gastha.2025.100687. eCollection 2025.
Colorectal cancer etiology is multifactorial and influenced by colonic environmental exposures leading to the accumulation of genetic lesions in precancerous polyps. There is growing recognition for a role of the gut microbiome in colorectal cancer progression, but the structure of the gut mucosal microbiome in the early stages of polyp growth is limited. The aim of this study was to characterize the gut mucosal microbiome from patients with low-grade conventional bowel neoplasia compared to symptomatic but polyp-free patients.
In this case-control study conducted at a tertiary referral hospital, 148 symptomatic patients undergoing colonoscopy were prospectively recruited. Mucosal biopsies adjacent to low-grade dysplasia (LGD) adenomatous polyps were used for 16S rRNA gene amplicon sequencing to define bacterial taxonomies relative to polyp-free controls.
Minimal differences in gut mucosa community diversity measures were observed between participants with or without LGD adenomas. After correcting for clinical covariates, patients with adenomas in the proximal colon revealed elevated amplicons from and unassigned . was the only microbe consistently found to be decreased in the gut mucosa of LGD adenoma patients compared with controls. Participants with LGD polyps in the distal colon showed more amplicons from and .
This study identified microbial candidates in the colonic mucosa that are associated with adenomatous LGD bowel neoplasia as an early step in the colorectal carcinogenesis pathway.
结直肠癌病因是多因素的，受结肠环境暴露影响，导致癌前息肉中遗传损伤的积累。肠道微生物群在结直肠癌进展中的作用日益受到认可，但息肉生长早期肠道黏膜微生物群的结构尚不清楚。本研究的目的是比较有低级别传统型肠道肿瘤的患者与有症状但无息肉的患者的肠道黏膜微生物群特征。
在一家三级转诊医院进行的这项病例对照研究中，前瞻性招募了148名接受结肠镜检查的有症状患者。对低级别发育异常（LGD）腺瘤性息肉旁的黏膜活检组织进行16S rRNA基因扩增子测序，以确定相对于无息肉对照组的细菌分类群。
在有或无LGD腺瘤的参与者之间，肠道黏膜群落多样性指标的差异极小。校正临床协变量后，近端结肠有腺瘤的患者显示 和未分类的扩增子升高。与对照组相比，LGD腺瘤患者的肠道黏膜中唯一始终被发现减少的微生物是 。远端结肠有LGD息肉的参与者显示来自 和 的扩增子更多。
本研究确定了结肠黏膜中与腺瘤性LGD肠道肿瘤相关的微生物候选物，这是结直肠癌发生途径的早期步骤。
