MicroRNA-595在炎症性肠病中的表达及其意义

Expression and Significance of MicroRNA-595 in Inflammatory Bowel Disease

背景:MicroRNAs调控异常与肠黏膜屏障损伤、肠道炎症以及肠道功能紊乱的发生有关。炎症性肠病(IBD)患者存在microRNAs表达异常。目的:探讨microRNA-595(miR-595)在IBD中的表达及其意义。方法:纳入2012年7月—2014年7月南京军区南京总医院收治的IBD患者100例,其中溃疡性结肠炎(UC)63例,克罗恩病(CD)37例,根据疾病活动性分为活动期UC(aU C)组、缓解期UC(rU C)组、活动期CD(aC D)组、缓解期CD(rC D)组,选取42例同时期健康体检者作为正常对照(NC)组。采集入选者的血清和肠黏膜组织标本,采用荧光定量PCR检测血清和肠黏膜组织miR-595表达水平。将分别含神经细胞黏附分子1(NCAM1)、成纤维细胞生长因子受体2(FGFR2)3’UTR序列的荧光素酶报告基因质粒与miR-595质粒共转染人结肠癌细胞株HCT116,检测miR-595对NCAM1、FGFR2转录活性的影响。结果:UC组和CD组血清和肠黏膜组织miR-595表达水平较NC组显著升高(P<0.05),aU C组、aC D组分别显著高于rU C组、rC D组(P<0.05)。MiR-595可结合NCAM1、FGFR2的3’UTR序列以抑制两者的转录活性。结论:MiR-595在IBD患者血清和肠黏膜组织中表达升高并与疾病活动性相关,其通过抑制紧密连接蛋白NCAM1和FGFR2表达,导致肠黏膜屏障受损,促进肠道炎症发生。MiR-595可作为诊断IBD及其活动性评估的血清生物学标记物。

Background： Dysregulation of microRNAs is associated with intestinal mucosal barrier injury,intestinal inflammation and intestinal dysfunction. Abnormal expression of microRNAs occurs in patients with inflammatory bowel disease（ IBD）.Aims： To investigate the expression and significance of microRNA-595（ miR-595） in IBD. Methods： A total of 100 patients with IBD at Nanjing General Hospital of Nanjing Military Command of PLA from July 2012 to July 2014 were enrolled,in which 63 cases were ulcerative colitis（ UC） and 37 cases were Crohn＇s disease（ CD）. According to disease activity,patients were divided into active UC（ aU C） group,remissive UC（ rU C） group,active CD（ aC D） group and remissive CD（ rC D） group. A total of 42 healthy subjects were served as normal control（ NC） group. Specimens of serum and intestinal tissue were collected. Expression of miR-595 in serum and intestinal tissue was determined by fluorescence quantitative PCR. Luciferase report gene plasmid containing the 3＇UTR of neural cell adhesion molecule 1（ NCAM1） or fibroblast growth factor receptor 2（ FGFR2） and plasmid containing miR-595 were co-transfected into human colon cancer cell line HCT116 to detect the effect of miR-595 on transcriptional activities of NCAM1 and FGFR2. Results： Expression of miR-595 in serum and intestinal tissue in UC and CD groups was significantly higher than that in NC group（ P〈0. 05）,and that in aU C and aC D groups was significantly higher than that in rU C and rC D groups,respectively（ P〈0. 05）. MiR-595 could down-regulate the transcriptional activities of NCAM1 and FGFR2 through directly binding to the 3 ＇UTR of NCAM1 and FGFR2. Conclusions： Expression of miR-595 in serum and intestinal tissue is increased in patients with IBD and correlates with disease activity. MiR-595 inhibits the expressions of tight junction protein NCAM1 and FGFR2,thereby inducing injury of intestinal mucosal barrier and promoting intestinal inflammation. MiR-595 can serve as a serum biomarker for diagnosis of IBD and disease activity evaluation.