【摘要】 目的：探讨湿热证大肠癌患者肠道菌群结构特点及其对肠癌发生的影响。方法：通过16S rRNA测序分析湿热证和无明显证候大肠癌患者肠道菌群特征，并将其粪菌提取液对伪无菌小鼠进行粪菌移植，同时通过AOM/DSS诱导小鼠肠癌发生。观察小鼠的体质量、成瘤数，比较各组细胞因子表达水平。结果：与无明显证型大肠癌患者比较，湿热证大肠癌患者具有显著不同的微生物群落结构，其中致病菌（如大肠杆菌属、别样杆菌属、肠球菌属、Intestinibacter菌属、嗜胆菌属等）的丰度明显增高，此外以大肠杆菌为代表的产LPS病原菌明显富集（P<0.01）。对AOM/DSS小鼠模型进行粪菌移植后，相较于无明显证型粪菌移植小鼠，湿热证粪菌移植小鼠体质量明显减轻（P<0.01），结肠肿瘤形成增多（P<0.01），且促炎细胞因子IL-6 mRNA表达显著增高（P<0.05）。结论：湿热证大肠癌患者具有致病菌增多和以LPS合成细菌增多为主要特点的肠道菌群结构，其肠道菌通过粪菌移植后可促进AOM/DSS小鼠肠癌发生。更多还原

【Abstract】 Objective: To explore profile of gut flora structure in colorectal cancer(CRC) patients with damp-heat syndrome(DHS) and the effects on the occurrence of CRC. Methods: The characteristics of fecal bacteria in CRC patients with different syndromes were sequenced by 16S rRNA analysis. Fecal bacterial suspensions prepared from patients were transplanted into pseudo germ-free mice, and AOM/DSS was used to induce the tumorigenesis in mice. Body weight, tumor number and expression levels of colonic pro-inflammatory cytokines were observed. Results: A significant difference in fecal microbial communities was found between CRC patients with DHS and uncertain syndrome(US). In the DHS group, the abundance of pathogenic bacteria(Escherichia-Shigella, Alistipes, Enterococcus, Intestinibacter, Bilophila, etc.) were significantly increased,of which lipopolysaccaride(LPS) producing bacteria represented by Escherichia-Shigella were more abundant in DHS cases than that of US cases(P<0.01). Following fecal microbiota transplantation(FMT) in AOM/DSS mouse model, more body weight losses(P<0.01), more colonic tumors(P<0.01) and higher mRNA expression of pro-inflammation cytokines IL-6(P<0.05)were observed in FMT-DHS group than those of FMT-US group. Conclusion: CRC patients with DHS have the special structure of intestinal microbiota characterized by the increase of pathogenic bacteria and LPS-producing bacteria, and the characteristic microbiota of DHS can upregulate the level of colonic inflammation and promote the tumorigenesis in AOM/DSS mice.更多还原