肠道微生态与宫颈癌合并放射性肠损伤的临床研究

Clinical study of intestinal microecology and intestinal radiation injury in cervical cancer patients

目的:探讨肠道微生态结构变化与宫颈癌放疗致放射性肠损伤的相关性。方法:以RTOG/EORTC晚期放射损伤分级为依据,将纳入研究34例宫颈癌放疗后病人肠道损伤分为0~4级,将入组病人分为放射性肠损伤组(RG)和无放射性肠损伤组即健康组(HG)。利用Illumina MiSeq高通量测序平台对粪便标本中肠道微生物的16S rRNA基因v4区序列进行测序,使用QIIME 2.0处理测序数据并分析肠道微生物丰富度和多样性,并通过PICRUSt预测了肠道微生物群的功能特征。结果:两组在肠道微生物丰富度、多样性均无显著性差异(P>0.05)。在菌群组成上,筛选出了5个与放射性肠损伤最为相关的菌属,分别为Acidaminococcus(氨基酸球菌属)、Pyramidobacter、Dialister(小杆菌属)、Megasphaera(巨球型菌属),f-Dethiosulfovibrionaceae uncl;在功能代谢上,发现RG肠道微生物群代谢类型出现了适应厌氧环境代谢途径和致病菌相关代谢途径上调的现象。结论:盆腔放射治疗直接或间接引起肠道粘膜受损、修复功能减弱和肠道抑菌能力降低,继而引起肠道微生态失衡。

Objective:To investigate the correlation between intestinal microecological changes and intestinal radiation injury caused by cervical cancer radiotherapy.Methods:Based on RTOG/EORTC late radiation morbidity scoring criteria,the intestinal lesions of 34 patients with cervical cancer after radiotherapy were graded into 0~4.Patients enrolled in the study were divided into Radiation-Induced Intestinal Injury Group(RG)and Health Group(HG).The Illumina MiSeq high-throughput sequencing platform was used to sequence the 16S rRNA gene v4 region of intestinal microbes in fecal specimens,using QIIME 2.0 to process sequencing data and analyze intestinal microbial richness and diversity,and predicting the functional characteristics of intestinal microbiota by PICRUSt.Results:There was no significant difference in intestinal microbial richness and diversity between the two groups(P>0.05).In the composition of the flora,five genus most related to intestinal radiation injury were screened,namely Acidaminococcus,Pyramidobacter,Dialister,Megasphaera,f-Dethiosulfovibrionaceae uncl.In terms of functional metabolism,it was found that the metabolic type of intestinal microbiota in the Radiation-Induced Intestinal Injury Group(RG)showed an upregulation of metabolic pathways adapted to anaerobic environment and metabolic pathways associated with pathogenic bacteria.Conclusion:Pelvic radiation therapy directly or indirectly causes intestinal mucosal damage,reduced repair function and decreased intestinal bacteriostatic ability,which in turn causes intestinal micro-ecological imbalance.