特异性敲除肠上皮Toll样受体4基因促进小鼠移植瘤的增殖  

Specific knockout of the intestinal epithelium TLR4 gene promotes the proliferation of mouse xenograft tumour

作　　者：李佳颖 陈银潇 李兆栋 白立鼎 王相玲 付慧 赵舒武 刘建卫 卢斌 Li Jiaying;Chen Yinxiao;Li Zhaodong;Bai Liding;Wang Xiangling;Fu Hui;Zhao Shuwu;Liu Jianwei;Lu Bin(College of Integrated Chinese and Western Medicine,Tianjin University of Traditional Chinese Medicine,Tianjin 301617,China)

机构地区：[1]天津中医药大学中西医结合学院,天津301617

出　　处：《解剖学杂志》2023年第1期9-14,F0003,共7页Chinese Journal of Anatomy

基　　金：国家自然科学基金(81873100)。

摘　　要：目的:从肠道菌群和肠黏膜屏障角度探讨肠上皮Toll样受体4(TLR4)基因特异性敲除(IEC-CreTLR4KO)促进小鼠皮下移植瘤增殖的可能机制。方法:设IEC-CreTLR4KO组、IEC-TLR4flox/flox组和BALB/c野生型组,注射CT-26结肠癌细胞于各组小鼠的右腋下皮肤,细胞数为4×10^(5)个,观察并记录各组小鼠移植瘤体积以及体质量,检测肿瘤增殖标记物Ki67;16S rDNA高通量测序检测各组小鼠结肠粪便,分析肠道菌群的丰度与多样性;GMrepo数据库分析差异菌的肿瘤相关性;光、电镜技术观察肠黏膜形态结构;免疫组织化学检测小鼠肠上皮细胞紧密连接蛋白ZO-1表达。结果 :相较于BALB/c组和IEC-TLR4flox/flox组,IEC-CreTLR4KO荷瘤组小鼠肿瘤体质量比显著增高;与BALB/c组相比,IEC-CreTLR4KO组小鼠肠道菌群丰度和多样性增加,其中f_Enterococcaceae、g_Erysipelatoclostridium及g_Mucispirillum丰度增高,而f_Tannerellaceae、g_RuminococcaceaeUCG_010丰度降低;上述关键差异菌与肿瘤等疾病密切相关;电镜观察显示IEC-CreTLR4KO组小鼠空肠上皮细胞间的连接结构松散,同时空肠和结肠上皮细胞ZO-1表达显著下降。结论 :肠上皮TLR4基因特异性敲除促进小鼠移植瘤的增殖,可能与该基因缺失后引起肠道菌群变化和肠黏膜屏障破坏密切相关。Objective:To investigate the possible mechanism of intestinal epithelial TLR4 gene-specific knockout(IEC-CreTLR4KO)promoting the proliferation of subcutaneous xenograft tumour in mice from the perspective of intestinal flora and intestinal mucosal barrier.Methods:Three groups,the IEC-CreTLR4KO group,IEC-TLR4flox/flox group,and BALB/c wild-type group,were set up.CT-26 colon cancer cells were injected into the right armpit skin of mice in each group,and the number of cells was 4×105.The tumor volume and body weight of the mice in each group were observed and recorded,and the tumor proliferation marker Ki67 was detected.16S rDNA highthroughput sequencing was used to detect the colonic feces of mice in each group to analyze the abundance and diversity of intestinal flora.The GMrepo database was used to analyze the tumor correlation of the differential bacteria.Morphology of intestinal mucosa was observed by light microscopy and electron microscopy.The expression of tight junction protein ZO-1 in mouse intestinal epithelial cells was detected by immunohistochemistry.Results:Compared with wild-type and IEC-TLR4flox/flox,the tumor-to-mass ratio of IEC-CreTLR4KO tumor-bearing mice was significantly increased.Compared with wild-type BALB/c,the IEC-CreTLR4KO mice had an increased gut flora abundance and diversity.Among them,the abundance of f_Enterococcaceae,g_Erysipelatoclostridium and g_Mucispirillum increased,while the abundance of f_Tannerellaceae,g_RuminococcaceaeUCG_010 decreased.The above key differential bacteria were closely related to diseases such as tumors.Electron microscopy showed that the junctional structure between jejunal epithelial cells in IEC-CreTLR4KO mice was loose,and the expression of ZO-1 in jejunal and colon epithelial cells was significantly decreased.Conclusion:The specific knockout of intestinal epithelial TLR4 gene promotes the proliferation of transplanted tumors in mice,which may be closely related to the change of intestinal flora and the destruction of intestinal mucosal barrier caused b

关 键 词：肠上皮 TOLL样受体4 基因敲除 移植瘤 肠道菌群 紧密连接 小鼠 

分 类 号：R730.2[医药卫生—肿瘤]