长链非编码RNA MIAT在非小细胞肺癌中的表达及功能研究

Effects of lncRNA MIAT on cell proliferation of human non-small-cell lung carcinoma

目的:研究长链非编码RNA心肌梗死相关转录本(MIAT)在非小细胞肺癌(NSCLC)组织及细胞系中的表达情况及其对NSCLC细胞功能的影响。方法:利用Gene Expression Omnibus(GEO)数据库提取GSE19804和GSE30219数据集的生物信息学资料和临床预后资料,分析MIAT在NSCLC组织和正常肺组织中的表达差异,以及MIAT表达水平与NSCLC患者生存期的关系;用q PCR检测25对NSCLC肿瘤组织和其癌旁组织,以及NSCLC细胞系A549、NCI-H266和NCI-H1299及人正常支气管上皮细胞系HBE中MIAT的表达情况;将MIAT si RNA(si-MIAT)和对照序列(si-NC)分别转染NSCLC细胞系A549,采用流式细胞术、CCK-8实验和细胞集落形成实验检测2组细胞的增殖情况,并且用q PCR和Western blot实验检测2组细胞中细胞周期蛋白D1(cyclin D1)和细胞周期蛋白依赖性激酶抑制剂1A(CDKN1A)的表达情况。结果:GSE19804数据集分析显示MIAT在NSCLC组织中的表达高于正常肺组织(P<0.05),GSE30219数据集分析显示MIAT高表达患者的生存期显著短于低表达患者(P<0.01)。此外,与癌旁正常组织和HBE细胞相比较,NSCLC组织和细胞系中MIAT的表达水平升高(P<0.05);si-MIAT组A549细胞中MIAT表达水平明显低于si-NC组(P<0.01),且细胞活力和细胞集落数均低于siNC组,差异均有统计学意义(P<0.05);同时,相较于si-NC组,si-MIAT组cyclin D1的表达受到明显抑制(P<0.05),而CDKN1A的表达明显升高(P<0.05)。结论:NSCLC组织及细胞系中MIAT呈高表达,沉默MIAT表达可明显抑制NSCLC恶性增殖的表型。MIAT可作为NSCLC靶向治疗的潜在靶标。

AIM:To explore the expression level of long non-coding RNA(lncRNA)myocardial infarction-associated transcript(MIAT)in the tissues and cells of non-small-cell lung carcinoma(NSCLC),and to investigate the effect of MIAT on the function of NSCLC cell line.METHODS:Bioinformatic data in microarray dataset GSE19804 from Gene Expression Omnibus(GEO)were collected for analyzing the difference expression of MIAT between NSCLC tissues and normal lung tissues.Clinical and prognostic data in microarray dataset GSE30219 from GEO were also collected for analyzing the correlation between the expression level of MIAT and the survival time of NSCLC patients.qPCR was applied to detect the expression of MIAT in 25 paired tumor tissues and corresponding adjacent normal tissues,normal lung epithelial HBE cell line and NSCLC A549,NCI-H266 and NCI-H1299 cell lines.The specific small interfering RNA for MIAT(si-MIAT group)or negative control sequence(si-NC group)was transfected into A549 cells,and flow cytometry,colony formation experiment and CCK-8 assay were employed to detect the proliferation of the cells in the 2 groups.The expression levels of cyclin D1 and cyclin-dependent kinase inhibitor 1A(CDKN1A)in the 2 groups were determined by qPCR and Western blot.RESULTS:In the GEO dataset GSE19804,the expression of MIAT in NSCLC tissues was significantly elevated compared with normal lung tissues(P<0.05).In the GEO dataset GSE30219,the overall survival time was significantly shorter in the patients with high expression of MIAT than the patients with low expression of MIAT(P<0.05).Furthermore,the levels of MIAT in both NSCLC tissues and cells were higher than those in adjacent normal tissues and normal cells(P<0.05).Compared with si-NC group,lower MIAT level,cell viability and cell colony number in si-MIAT group with statistical significance were observed(P<0.05).Meanwhile,compared with si-NC group,the expression of cyclin D1 in si-MIAT group was significantly decreased(P<0.05),and inversely,the expression of CDKN1A in si-MIAT group was significantly increased(P<0.05).CONCLUSION:There is high expression of MIAT in NSCLC tissues and NSCLC cells,and knockdown of MIAT expression inhibits NSCLC cell proliferation,which provides a potential target of targeted therapy for NSCLC.