根據行政院衛生署公布國人的十大死因，惡性腫瘤已連續第28年佔居榜首，而大腸癌盛行於已開發國家，為台灣癌症發生率第二位，死亡率第三位。Tazarotene-induced gene 1 (TIG1) 又稱為 retinoic acid receptor responder gene 1 (RARRES1)，過去之研究顯示 TIG1 蛋白具有抑制前列腺癌細胞侵襲及生長之活性。TIG1在許多正常組織中皆有表現，但在癌細胞中卻經常呈現低量表現或不表現。本研究目的在探討在人類大腸直腸癌中TIG1蛋白的表現，或許將是作為早期大腸直腸癌診斷的危險因子。本實驗利用反轉錄聚合酵素連鎖反應探討在大腸直腸癌患者正常及腫瘤組織中TIG1蛋白的表現，結果發現，大部分正常及腫瘤組織都有表現，只有少數腫瘤組織的TIG1蛋白沒有表現。接著利用免疫化學染色來看TIG1蛋白在大腸直腸癌患者組織檢體中的表現，結果發現，比較病人的性別、年齡、腫瘤的分化、原發腫瘤（T）分期、區域淋巴結（N）分期及遠處轉移（M）分期以卡方檢定(χ2 -test)來分析，P值均＞0.05，無顯著性差異。總結，本實驗TIG1蛋白的表現在大腸直腸癌患者正常及腫瘤組織並無差異。

According to the Department of Health (Executive Yuan, Taiwan) announcement for top ten leading causes of death, the malignant tumor occupied the first place continuously during nearly 28 years. Colorectal cancer (CRC) which has become prevalent in developed countries, the second highest frequency of cancer and third highest cause of death in Taiwan. Tazarotene-induced gene 1(TIG1) is also known as retinoic acid receptor responder gene 1(RARRES1). TIG1 protein functions to suppress invasion and growth of prostate cancer cells. The TIG1 is expressed in several normal tissues, but frequently down-regulated in cancer cells.
This study focused on the expression of TIG1 protein in colorectal cancer, and investigated whether TIG1 could be a factor to diagnose early colorectal cancer. First, we used reverse transcriptase polymerase chain reaction (RT-PCR) to determine the TIG1 expression in non-tumor and tumor parts of the colorectal cancers. Our result showed that RNA transcripts of TIG1 were detectable in some tumor parts of colorectal cancers, however, TIG1 was undetectable in most normal parts. We also used immunochemistry stain (IHC) to measure the TIG1 expression in tissue microarray of colorectal cancer. The result demonstrated that no correlation between TIG1 expression and patients’ pathological parameters such as gender, age, tumor differentiation grading, T-classification, N-classification and M-classification (p>0.05). In conclusion, our results suggested that the TIG1 protein may not involve in colorectal tumorigenesis.

壹、 中英文摘要…………………………………………….. 1
貳、 序論…………………………………………………….. 3
參、 研究動機……………………………………………….. 13
肆、 材料、儀器及實驗方法……………………………….. 14
伍、 實驗結果……………………………………………….. 22
陸、 討論…………………………………………………….. 24
柒、 參考文獻……………………………………………….. 27
捌、 圖表及圖表說明……………………………………….. 29

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