MicroRNA-19b和microRNA-106b調控多形性神經膠母細胞瘤細胞增生的分子機制探討

MOLECULAR MECHANISMS OF MICRORNA-19b AND MICRORNA-106b IN REGULATING PROLIFERATION OF GLIOBLASTOMA MULTIFORME CELLS

周稚瑋(Chih-Wei Chou)

指導教授 ： 陳瑞明

臺北醫學大學/醫學院/醫學科學研究所/碩士(2012年)

https://doi.org/10.6831/TMU.2012.00144

摘要

多形性神經膠母細胞瘤( glioblastoma )在腦瘤中是最普遍、最具侵犯並且是致死率最高的，當中惡性程度最高的膠質母細胞瘤也是多形性神經膠母細胞瘤，所以患有多形性神經膠母細胞瘤的患者通常存活率大致上都不理想，而近幾年，對於治療患有多形性神經膠母細胞瘤的患者，大都是以延緩病情為主，目前還沒有有效的根治方法。近幾年研究發現在腫瘤形成過程中，微型核醣核酸( MicroRNAs )會參與其中並調控之，包含細胞增生、細胞凋亡和腫瘤發展等。MicroRNAs是內生性的單股核醣核酸，參於調控mRNA的降解並抑制其轉譯。所以我們透過MicroRNA微陣列方式去分析人類正常腦組織與多形性神經膠母細胞瘤病患組織，可以得知miR-19b和miR-106b在多形性神經膠母細胞瘤組織中表現高於正常腦組織。在正常星形膠質細胞株與多形性神經膠母細胞瘤細胞株中也使用MicroRNA微陣列方式去分析microRNAs表現，發現在多形性神經膠母細胞瘤細胞中miR-106b表現較高，而miR-19b則表現較低。因此，我們利用細胞株去進一步佐證miR-19b或者miR-106b對細胞增生的影響，首先在多形性神經膠母細胞瘤U-87 MG細胞株中利用miR-19b或者miR-106b抑制劑，其中miR-19b被抑制之後，發現多形性神經膠母細胞瘤細胞增生不被抑制，而miR-106b被抑制之後，發現可以顯著性地被抑制細胞增生於U-87 MG細胞中。且在多形性神經膠母細胞瘤細胞株動物模式中，可以發現miR-106b的表現量會隨者腫瘤發展而增加。另外在患有多形性神經膠母細胞瘤病患之plasma中，也發現miR-106b表現高於正常plasma。最後分析miR-19b和miR-106b所預測的目標基因PTEN和PTENP1基因表現量，在U-87 MG細胞中顯著性低於正常星形膠質細胞。此外也偵測miR-106b另外兩個所預測的目標基因，p21和RB1，其中在U-87 MG細胞株的p21蛋白表現無差異，而RB1蛋白表現則是顯著性低。因此可證明miR-106b在多形性神經膠母細胞瘤是大量表現的。

關鍵字

多形性神經膠母細胞瘤；微型核醣核酸；細胞增生

並列摘要

Glioblastoma was the most common, aggressive and lethal type of primary brain tumor, and it is the most malignant glioma tumor. Despite treatments with surgery, radiation therapy, and chemotherapy, prognosis remains poor. Mounting evidence indicated that microRNAs might play a fundamental role in tumorigenesis, controlling cell proliferation and apoptosis. MicroRNAs are endogenously small non-coding RNAs which are key post-transcriptional regulators of gene expression. Here, through analyzing the miRNA-array profiles of human glioblastoma and the adjacent normal brain tissue, we found that miR-19b and miR-106b were significantly up-regulated in glioblastoma tissue, which was confirmed in astrocyte and glioblastoma cells. Additionally, we found that miR-106b was higher in glioblastoma cells by analyzing the miRNA-array profiles of human astrocyte and glioblastoma cells, which was confirmed in astrocyte and glioblastoma cells. But miR-19b was lower in glioblastoma cells. The inhibition of miR-19b did not suppress proliferation of glioblastoma U-87 MG cells. The inhibition of miR-106b significantly suppressed proliferation of glioblastoma U-87 MG cells. We established a human model of glioblastoma in nude mice and also found that expression of miR-106b was increased during tumor development in nude mice injected with glioblastoma cells. And the expression of miR-106b was higher in glioblastoma plasma. On the other hand, the expression of PTENP1 and PTEN mRNA, which were predicted target gene of miR-19b and miR-106b, were lower in glioblastoma U-87 MG cells. Then other predicted target gene of miR-106b include p21 and RB1. The levels of p21 protein were measured in glioblastoma U-87 MG cells, and the levels of RB1 protein were lower. Thus miR-106 were high in glioblastoma.

並列關鍵字

glioblastoma；microRNA；proliferation

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