原发性肝癌H-ras12V小鼠 肠道微生态的初步研究

目的探索原发性肝癌小鼠(H-ras12V小鼠)肠道微生态的特异性。方法设立7月龄的H-ras12V小鼠为实验组,C57BL/6J常态小鼠为对照组。小鼠在标准饮食下饲养2个月。于实验第8周无菌收集小鼠粪便,进行V3-V4高可变区16SrDNA基因组测序,分析两组小鼠肠道菌群多样性和组成的差异。结果肝癌小鼠成瘤率为100%。α多样性:稀释曲线趋于平缓,样品测序数据量较合理。β多样性:通过Anosim分析确定两组组间差异显著大于组内差异(R=0.2857,P=0.0037)。菌群结构:门水平优势菌群有拟杆菌门、厚壁菌门、变形菌门等,属水平优势菌群有Barnesiella、Alloprevotella、拟杆菌属等。显著性差异物种:通过Kruskal-Wallis test分析,发现拟杆菌属等7个属差异有统计学意义(P0.05)。结论原发性肝癌H-ras12V小鼠肠道微生态多样性和菌群结构有显著差异,其中拟杆菌属及其特殊结构鞘脂与肝硬化及肿瘤关系密切,可能与肝癌存在联系。

A preliminary study on intestinal microflora of mice with primary liver cancer

Abstract: Objective To explore the specificity of intestinal microecology in mice with primary liver cancer (H-ras12V mice). Methods 7-month-old H-ras12V mice were set up as the observation group, with normal C57BL/6J mice as the control group. The mice were fed with a standard diet for 2 months. In the 8th week of the experiment, the excrement samples of mice were collected aseptically. And the 16S rDNA genome of V3 - V4 high variable region was sequenced to analyze the differences in the diversity and the composition of intestinal flora of mice between two groups. Results Tumor formation rate in H-ras12V mice was 100 percent. Alpha diversity analysis showed that the dilution curve tends to be gentle and the sequencing data of samples were reasonable. Beta diversity analysis showed that the intergroup difference was significantly greater than the intragroup difference based on Anosim analysis (R=0.2857, P=0.0037). As to the microbial community structure, the predominant intestinal microbiota included Bacteroidetes, Firmicutes and Proteobacteria etc at phyla level, and Barnesiella, Alloprevotella and Bacteroides etc at genus level. Significant difference analysis found significant difference between groups (P<0.05) in 7 genera including Bacteroides etc based on Kruskal-Wallis test. Conclusion There are significant differences in the intestinal flora of H-ras12V mice with primary liver cancer. Bacteroides and its specific structure, sphingolipids, are closely related with liver cirrhosis and tumor, which may be connected with liver cancer.