探討microRNAs與肝癌和大腸直腸癌之標靶基因

MicroRNAs target genes - Liver and colorectal cancer

廖志家(Chih-Chia Liao)

指導教授 ： 吳家樂

亞洲大學/資訊學院/生物資訊學系碩士班/碩士(2007年)

摘要

微核糖核酸(MicroRNA)是髮夾型的小分子RNA，僅約二十幾個鹼基，是生物體內一種內生性機制，普遍存在於動物、植物及病毒的基因體中，具有調控mRNA的壽命、轉譯（transcription）蛋白的數量與影響基因表現的能力，也因此microRNA在基因轉譯（transcription）成蛋白質過程中扮演重要的角色，可作為治療延緩腫瘤生長的目標。當MicroRNAs出錯時，可能引發諸如具有癌症特徵的失控的細胞分裂等異常情況。
本研究主要針對miRNAs與肝癌、大腸直腸癌標靶基因之關連性其目的為尋找人類miRNA標靶cancer的mRNA序列、探討miRNA與Tumor Suppressors Gene,(TSG)抑制基因之可能性。我們透過腫瘤microarray的實驗，共發現有13個肝癌腫瘤基因表達水準向下調整，這些miRNAs可能會抑制癌症基因的表達量。而這些癌症基因是否扮演Tumor Suppressors Gene的角色就非常有趣了，這也將帶來miRNA和癌症的研究關係比以前更密切。

關鍵字

微核醣核酸 ； 抑制基因 ； 癌症 ； 肝癌 ； 大腸直腸癌

並列摘要

Micro-Ribonucleic Acid (miRNA),a hairpin-like small molecular RNA with approximately twenty basic groups,is one kind of endogenetic mechanism in organism which generally exists in the animal, the plant and in virus. miRNA has the abitity to regulate the life of mRNA, translation of protein and influence gene expression. Therefore,microRNA plays an important role in the process of translating to protein,and, could be the goal of slowing down the growth of tumor. When errors occurring in MicroRNAs,they could trigger some unusual circumstance,such as uncontrolled cell division which leads to cancer.
This research mainly aims at identifying miRNAs targeting regions of the liver and colorectal cancers mRNA sequences. A set of putative targeted gene regions are identified, where the gene expression levels of these genes are studied by retrieving from certain primary liver tumors microarray experiments. Thirteen cancer genes are found to be down-regulated across these experiments.This suggests the possibility of these miRNAs could possibly suppressing the expression level of these liver cancer related genes. The possibility of these cancer genes play the role of the tumor suppressor genes would be highly interesting. This will bring the relationship of miRNA and cancer research closer than before.

並列關鍵字

miRNA ； Tumor Suppressors Gene ； cancer ； liver cancer ； colorectal cancer

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