State Key Laboratory for Infectious Diseases Diagnostics and Treatment, the First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China.
PLoS One. 2012;7(6):e39743. doi: 10.1371/journal.pone.0039743. Epub 2012 Jun 28.
Recent reports have suggested the involvement of gut microbiota in the progression of colorectal cancer (CRC). We utilized pyrosequencing based analysis of 16S rRNA genes to determine the overall structure of microbiota in patients with colorectal cancer and healthy controls; we investigated microbiota of the intestinal lumen, the cancerous tissue and matched noncancerous normal tissue. Moreover, we investigated the mucosa-adherent microbial composition using rectal swab samples because the structure of the tissue-adherent bacterial community is potentially altered following bowel cleansing. Our findings indicated that the microbial structure of the intestinal lumen and cancerous tissue differed significantly. Phylotypes that enhance energy harvest from diets or perform metabolic exchange with the host were more abundant in the lumen. There were more abundant Firmicutes and less abundant Bacteroidetes and Proteobacteria in lumen. The overall microbial structures of cancerous tissue and noncancerous tissue were similar; however the tumor microbiota exhibited lower diversity. The structures of the intestinal lumen microbiota and mucosa-adherent microbiota were different in CRC patients compared to matched microbiota in healthy individuals. Lactobacillales was enriched in cancerous tissue, whereas Faecalibacterium was reduced. In the mucosa-adherent microbiota, Bifidobacterium, Faecalibacterium, and Blautia were reduced in CRC patients, whereas Fusobacterium, Porphyromonas, Peptostreptococcus, and Mogibacterium were enriched. In the lumen, predominant phylotypes related to metabolic disorders or metabolic exchange with the host, Erysipelotrichaceae, Prevotellaceae, and Coriobacteriaceae were increased in cancer patients. Coupled with previous reports, these results suggest that the intestinal microbiota is associated with CRC risk and that intestinal lumen microflora potentially influence CRC risk via cometabolism or metabolic exchange with the host. However, mucosa-associated microbiota potentially affects CRC risk primarily through direct interaction with the host.
最近的报告表明，肠道微生物群参与了结直肠癌（CRC）的进展。我们利用基于焦磷酸测序的 16S rRNA 基因分析来确定结直肠癌患者和健康对照者的肠道微生物群的整体结构；我们研究了肠道腔、癌组织和匹配的非癌正常组织中的微生物群。此外，我们使用直肠拭子样本研究了黏膜附着微生物的组成，因为肠道清洁后，组织附着细菌群落的结构可能会发生改变。我们的研究结果表明，肠道腔和癌组织的微生物结构存在显著差异。在腔中，从饮食中增强能量收获或与宿主进行代谢交换的菌群更为丰富。腔中有更多的厚壁菌门和较少的拟杆菌门和变形菌门。癌组织和非癌组织的整体微生物结构相似；然而，肿瘤微生物群的多样性较低。与健康个体相匹配的微生物相比，CRC 患者的肠道腔微生物群和黏膜附着微生物群的结构不同。乳杆菌科在癌组织中富集，而粪杆菌减少。在黏膜附着的微生物群中，双歧杆菌、粪杆菌和布劳特氏菌在 CRC 患者中减少，而梭菌、卟啉单胞菌、消化链球菌和莫比氏菌在 CRC 患者中富集。在肠道腔中，与代谢紊乱或与宿主进行代谢交换相关的主要菌群，如肠杆菌科、普雷沃氏菌科和科里杆菌科，在癌症患者中增加。结合以往的报告，这些结果表明肠道微生物群与 CRC 风险相关，肠道腔微生物群可能通过共代谢或与宿主进行代谢交换影响 CRC 风险。然而，黏膜相关的微生物群主要通过与宿主的直接相互作用影响 CRC 风险。
