结肠癌microRNA表达谱检测及生物信息学分析

目的 探讨miRNA(microRNA,微小RNA)在结肠癌组织中的表达特征及生物学功能.方法 选取临床特征相似的3对结肠癌组织及其配对正常黏膜组织,应用Exiqon miRNA芯片检测miRNA在结肠癌及其配对组织中差异表达情况;3个差异表达的miRNA被选取进行qPCR验证;生物信息学分析差异表达的miRNA及其靶向基因在结肠癌进展中的作用机制.结果 芯片结果显示,在3对结肠癌组织中有201个miRNA出现上调表达,94个下调表达(差异倍数>2),差异有统计学意义(P<0.05).qPCR结果显示,与对照组织比较,选取的3个miRNA中hsa-miR-18b-3p、hsa-miR-31-5p在结肠癌组织中表达上调,hsa-miR-142-3p表达下调,与芯片结果一致,差异有统计学意义(P<0.05).GO及pathway分析显示差异表达的miRNA涉及结肠癌细胞的分化、迁移、定位、增生及RNA、蛋白合成等功能调控,与细胞粘附、结肠癌发生发展等信号途径的激活相关.结论 结肠癌组织中miRNA存在异常表达,可能涉及结肠癌的发生、发展.

Expression profile of microRNAs and bioinformatics analysis in human colon cancer tissues

Objective To investigate the expression profile and biological functions of miRNAs (microRNA) in human colon cancer tissues. Methods The expression profiles of miRNAs were compared between 3 pairs of colon cancer and its adjacent normal tissues using a Exiqon miRNA array, following which quantitative PCR (qPCR) was em-ployed to confirm the results of the miRNA array, and 3 differentially expressed miRNAs were selected for qPCR valida-tion. Bioinformatics was used to analyze the biological function of the differentially expression miRNAs and its target genes in colon cancer. Results Compared with adjacent normal mucosal tissues, 201 miRNAs were up-regulated and 94 miRNAs were down-regulated in colon cancer tissues (fold>2), the difference was statistically significant (P<0.05). The qPCR results showed that, compared with the control group, the expression of hsa-miR-18b-3p and hsa-miR-31-5p were up-regulated and the expression of hsa-miR-142-3p was down regulated in colon cancer tissues, which were con-sistent with microarray-based expression analysis, with statistically significant difference (P<0.05). Furthermore, the on-line GO and KEGG pathwany analysis revealed that the differentially expressed miRNAs may be involving cell differen-tiation, migration, localization, proliferation, synthesis of RNA and protein and other biological functions, and perhaps related to cell adhesion and activation of signaling pathways of colon cancer development. Conclusion There are ab-normal expression of miRNAs in colon cancer tissues, which may be related to colon cancer tumorigenesis.