结直肠癌组织中细菌的分布及其与miR-23b和自噬相关蛋白ATG12表达的关系

Distribution of bacteria in colorectal cancer and its relationship with expression of miR-23b and autophagy-related protein ATG12

目的探讨结直肠癌组织中细菌的分布及其与miR-23b和自噬相关蛋白ATG12表达的关系。方法收集新疆医科大学第三临床医学院20例病理诊断明确、临床病历资料完整的结直肠癌患者的癌组织和远端正常组织样本,匀浆后细菌培养,采用16SrDNA扩增子测序的方法检测癌组织与远端正常组织菌群组成,qPCR检测具核梭杆菌(Fn)、miR-23b以及自噬相关蛋白ATG12的表达量。结果在门水平上,变形菌门、梭杆菌门、厚壁菌门、类杆菌门是结直肠癌患者结直肠组织部位微生物群落中最丰富的菌群,且癌组织中的变形菌门、类杆菌门数量显著高于远端正常组织。在属水平上,副杆菌属、大肠埃氏菌属-志贺氏菌属、链球菌属、维氏菌属、镰刀菌属、拟杆菌属是结直肠癌患者结直肠组织部位微生物群落中最丰富的菌群,且癌组织中的大肠埃氏菌属-志贺氏菌属、镰刀菌属、拟杆菌属数量显著高于远端正常组织,而链球菌、维氏菌属的数量显著低于远端正常组织。qPCR结果显示,结直肠癌组织内Fn mRNA的相对表达量显著高于远端正常组织,差异有统计学意义(P<0.001);miR-23b mRNA(P<0.001)和ATG12 mRNA(P<0.05)的相对表达量显著低于远端正常组织。结论结直肠癌患者的癌组织和远端正常组织菌群数量的差异与结直肠癌的发生有密切联系,具核梭杆菌是对结直肠癌有较大影响的差异菌属,并且可能与miR-23b、结直肠癌细胞自噬之间存在一定的联系。

Objective To investigate the distribution of bacteria in colorectal cancer tissues and the relationship with the expression of miR-23b and autophagy-related protein ATG12.Methods 20 samples of colorectal cancer patients with clear pathological diagnosis and complete clinical records were collected from the hospital.After homogenization,the bacterial culture was used to detect the flora composition of carcinoma tissues and distal normal tissues by 16SrDNA amplicon sequencing,then qPCR was used to detect the expression of Fusobacterium nucleatum Fn,miR-23b and autophagy-related protein ATG12.Results At the phylum level,Proteobacteria,Fusobacteriota,Firmicutes and Bacteroidota were the most abundant flora in the microbial community of colorectal tissues of patients with colorectal cancer,while the number of Proteobacteria and Bacteroidota in cancer tissues was significantly higher than that in distal normal tissues.At the genus level,Parabacteroides,Escherichia-Shigella,Streptococcus,Vibrio,Fusarium and Bacteroides were the most abundant microbial communities in colorectal tissues of patients with colorectal cancer,the number of Escherichia-Shigella,Fusarium and Bacteroides in cancer tissues was significantly higher than that in distal normal tissues,while the number of Streptococcus and Vibrio was significantly lower than that in distal normal tissues.The results of qPCR showed that the relative expression of Fn mRNA in colorectal cancer tissues were significantly higher than that in distal normal tissues,and the difference was statistically significant(P<0.001);the relative expression levels of miR-23b mRNA(P<0.001)and ATG12 mRNA(P<0.05)were significantly lower than those in distal normal tissues.Conclusion The difference in the number of bacterial flora between cancer tissues and distal normal tissues of the patients with colorectal cancer is closely related to the occurrence of colorectal cancer.Fusobacterium nucleatum is a differential bacterial genus that has a significant impact on colorectal cancer,which may be related to miR-23b and autophagy of colorectal cancer cells.