无淋巴结转移结肠癌微小核糖核酸表达谱的初步研究

目的:探讨无淋巴结转移结肠癌微小核糖核酸(microRNA)表达谱,筛选与结肠癌早期发生、发展相关的特异性microRNA.方法:选取手术、病理证实未发生淋巴结转移的结肠癌及大于癌旁5 cm结肠组织标本各3例,抽提分离miRNA,与Agilent microRNA基因芯片杂交,并进行图像和数据分析.运用microRNA特异引物对差异表达的microRNA进行荧光定量实时聚合酶链反应(RT-RCR)验证.结果:筛选出在结肠癌中差异表达的microRNA有14个,其中12个microRNA表达水平增高,分别为miR-106b、miR-135b、miR-18a、miR-18b、miR-196b、miR-19a,miR-224、miR-335、miR-424、miR-20a*、miR-301b和miR-374a;2个microRNA表达水平降低,分别为miR-378和miR-378*.miR-106b和miR-19a下游存住符合要求的靶基凶数目众多.检测了芯片中显示表达上凋的miR-18a和miR-135b在3例结肠癌组织和癌旁组织中的表达,结果显示miR-18a和miR-135b在3例痛组织和癌旁组织中表达均上调;荧光定量RT-PCR结果与microRNA芯片的结果符合.结论:miR-106b、miR-135b、miR-18a、miR-18b、miR-196b等microRNA在结肠癌与癌旁组织中存在差异表达,预测其下游靶基因中大部分与肿瘤相关,提示它们可能在结肠癌早期发生、发展讨程审起着重要的调控作用.

Preliminary study on microRNA expression profiles of colonic cancer without lymph node metastasis

Objective To investigate microRNA expression profiles of colonic cancer without lymph node metastasis and identify the specific microRNAs associated with carcinogenesis of colon.Methods Cancerous and para-cancerous tissues (5 cm from cancer tissues of the colon) confirmed without lymph node metastasis were collected from 3 patients. The microRNAs were extracted and isolated by mirVana RNA kit. Hybridizations were made by applying the microRNAs to Agilent microRNA microarray. Data analysis was done by software of Feacture Extraction. The discovered microRNAs were confirmed by real time PCR assay. Results Twelve out of 14 microRNAs associated with colonic cancer were up-regulated in colonic tissues. They were miR-106b, miR-135b,miR-18a,miR-18b,miR-196b, miR-19a, miR-224, miR-335, miR-424, miR-20a' , miR-301b and miR-374a. The rest two of miR-378 and miR 378* were down-regulated. Two up-regulated microRNAs (miR-18a and miR-135b) were detected in 3 pairs of cancerous and para-cancerous tissues. The expression level of miR-18a and miR-135b were accordant with the results of real time PCR.Conclusions microRNA.such as miR-106b,miR-135b.miR-18a.miR-18b,miR-196b,ect,were differentially expressed between cancerous and para-cancerous tissues.Many of these target genes are supposed to participate in the process of multiple tunmorgenesis.These microRNAs play an important role in the carcinogenesis of colon.