MicroRNA在鼻咽癌中的表达研究

发布时间：2018-05-10 14:20

本文选题：microRNA + 鼻咽癌　；参考：《复旦大学》2010年硕士论文

【摘要】：microRNA是最近研究发现的一类长度约为19～25个核苷酸的非编码单链小RNA分子,其通过与靶基因的3’端非翻译区互补配对结合的方法,从而调控内源基因的表达。miRNA作为生物体生长发育的重要调控基因,其主要研究方向是探明miRNAs与疾病的关系,尤其是miRNA与肿瘤的关系。虽然近年来对miRNA的研究越来越广泛,但多集中于肺癌、前列腺癌、乳腺癌、结肠直肠癌等较为常见和广泛的癌症。因为鼻咽癌的地区分布极不平衡,具有明显的种族聚集性和地域性,因此目前国外对其的研究还不是很深入。鼻咽癌是一种上皮源性恶性肿瘤,绝大多数属于低分化鳞状细胞癌,恶性程度高,早期易发生淋巴结和全身远处转移,具有相当高的死亡率。据世界卫生组织估计,鼻咽癌80%发生于中国,尤其高发于中国广西及广东地区。因此我们意在探索性的研究miRNA在鼻咽癌发生发展中的调控作用。我们利用Illumina microRNA表达谱芯片,对8例鼻咽咽癌组织样本和4例正常组织样本进行了miRNA表达谱分析。运用Illumina BeadStudio软件读取芯片数据,完成芯片数据归一化及筛选修补处理后,利用SAM软件及Cluster软件进行差异基因分析及聚类分析。我们筛选出了41条在鼻咽癌组织和正常组织中差异表达的miRNA,其中包括6条上调基因(miR-135b, miR-18a, miR-106b等)和35条下调基因(miR-34b, miR-34c, miR-10b, let-7, miR-449, miR-497等)。为了验证芯片结果的可靠性,我们应用定量RT-PCR的方法检测了差异表达基因miR-34、let-7g以及非差异表达基因miR-30c的表达情况,RT-PCR结果与芯片结果吻合。同时,我们还发现这些差异表达miRNA的聚类结果能够较好的与病人的临床分期联系起来。我们通过Targetscan数据库,对差异表达miRNA的靶基因进行预测,并将预测结果输入GenMAPP软件进行生物学通路分析。在通路分析中,大部分靶基因富集度高的通路都涉及到信号转导及与癌症发生相关的通路,例如EGFR-1信号通路,MAPK信号通路等等。其中,小GTP酶介导的信号转导通路最为显著。同时,Wnt信号通路的显著性,则与我们实验室过去在鼻咽癌cDNA表达谱的研究结果相吻合。继续深入研究这些差异miRNA在生物学通路中的调控作用,以及寻找与鼻咽癌发生发展进程相关的临床诊断标记物,则是我们未来的努力的方向。
[Abstract]:MicroRNA is a class of non-coding single-stranded small RNA molecules with a length of about 19- 25 nucleotides, which are found by complementary pairing with the 3'untranslated region of the target gene. Therefore, the expression of endogenous genes is regulated by .miRNA as an important regulatory gene for the growth and development of organism. Its main research direction is to find out the relationship between miRNAs and disease, especially the relationship between miRNA and tumor. Although the research on miRNA has been more and more extensive in recent years, it mainly focuses on the common and widespread cancers such as lung cancer, prostate cancer, breast cancer, colorectal cancer and so on. Because the regional distribution of nasopharyngeal carcinoma is very unbalanced and has obvious ethnic aggregation and regionality, the research on nasopharyngeal carcinoma at present is not very thorough. Nasopharyngeal carcinoma (NPC) is an epithelial-derived malignant tumor, most of which belong to poorly differentiated squamous cell carcinoma. The World Health Organization estimates that 80% of nasopharyngeal carcinomas occur in China, especially in Guangxi and Guangdong. Therefore, we intend to explore the regulatory role of miRNA in the carcinogenesis and development of nasopharyngeal carcinoma. The miRNA expression profiles of 8 nasopharyngeal carcinoma tissues and 4 normal tissues were analyzed by Illumina microRNA microarray. Illumina BeadStudio software is used to read chip data, and after normalization of chip data and screening repair, differential gene analysis and clustering analysis are carried out by SAM software and Cluster software. We screened 41 differentially expressed miRNAs in nasopharyngeal carcinoma and normal tissues, including 6 up-regulated genes miR-135b, miR-18a, miR-106b) and 35 down-regulated genes miR-34b, miR-34c, miR-10b, let-7, miR-449, miR-497 and so on. In order to verify the reliability of the microarray results, the differential expression gene miR-34let-7g and the non-differentially expressed gene miR-30c were detected by quantitative RT-PCR. The results of RT-PCR were consistent with those of the microarray. At the same time, we also found that the clustering results of these differentially expressed miRNA could be well correlated with the clinical stages of the patients. The target genes of differentially expressed miRNA were predicted by Targetscan database, and the predicted results were input into GenMAPP software for biological pathway analysis. In pathway analysis, most of the pathways with high target gene enrichment are involved in signal transduction and carcinogenesis related pathways, such as EGFR-1 signaling pathway, MAPK signaling pathway and so on. Among them, the signal transduction pathway mediated by small GTP enzyme was the most significant. At the same time, the significance of Wnt signaling pathway was consistent with the previous results of our laboratory studies on cDNA expression profiles in nasopharyngeal carcinoma (NPC). Further study on the regulatory role of miRNA in biological pathways and identification of clinical diagnostic markers related to the progression of nasopharyngeal carcinoma are the directions of our future efforts.
【学位授予单位】：复旦大学
【学位级别】：硕士
【学位授予年份】：2010
【分类号】：R739.63

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