探討植物萃取液抑制大腸直腸癌之抗癌作用機轉

To investigate the anti-cancer mechanisms of plant extracts in colorectal cancer in vitro and in vivo

陳怡婷(Yi-Ting Chen)

指導教授 ： 蔡女滿

中山醫學大學/醫學科技學院/醫學檢驗暨生物技術學系碩士班/碩士(2015年)

摘要

大腸直腸癌是世界上最普遍的惡性腫瘤之一，在美國之發生率為第三名，死亡率排行第四名，在台灣之發生率及死亡率都為第三名，目前的治療以手術切除搭配不同之化療藥物，因而造成許多副作用，其中最嚴重為對於器官之損害。然而在現有的治療之下，約有一半之患者會有復發之現象，而造成死亡率提高，五年存活率只有12.5%，因此開發新藥物來治療大腸直腸癌是有其必要性。在實驗室先前的實驗中，利用篩藥平台篩選一系列之植物萃取液，其中發現廣藿香 (Pogostemon patchouli, PPa)、雪松 (Cedrus atlantica, CAt)較有效的抑制大腸直腸癌，因此在本實驗選用廣藿香、雪松之粗萃物及純化物Patchouli alcohol (PAO)及Cedrol來研究是否對於大腸直腸癌具有抑制之效果，並且探討其抗癌機轉。在實驗中，先利用MTT assay得知，PPa、CAt、PAO和Cedrol能有效抑制大腸直腸癌細胞生長，且對於正常細胞株之毒性較低，合併臨床藥物5-Fluorouracil (5-FU)具有協同之效果，另外實驗結果顯示PPa、CAt、PAO和Cedrol能促使細胞週期停滯於G0/G¬¬1 phase和G2/M phase，此外，Sub-G1 phase之百分比隨著時間增加而增加。利用TUNEL assay也證實PPa、CAt、PAO和Cedrol能誘發細胞進行細胞凋亡，並啟動外在及內在細胞凋亡路徑，使大腸直腸癌之細胞死亡。在動物實驗中，PPa、CAt可以有效抑制腫瘤於動物體內生長並且延長動物存活時間、抑制體內腫瘤細胞增生、誘發腫瘤細胞凋亡、並且抑制血管生成及腫瘤轉移。因此，在體外或體內實驗結果皆證實廣藿香及雪松透過抑制細胞週期運行，誘發腫瘤進行細胞凋亡，並且抑制血管新生和腫瘤轉移達到抑制大腸直腸癌之效果，因此具有潛力開發為抗癌藥物。

關鍵字

大腸直腸癌 ； 廣藿香 (PPa) ； 雪松 (CAt) ； Patchouli alcohol (PAO) ； Cedrol ； 細胞周期 ； 細胞凋亡

並列摘要

Colorectal cancer is one of the most common malignant tumor in worldwide. In the United States, colorectal cancer is the third diagnosed cancer and the fourth cause of cancer death; it is the third one in diagnosed cancer and causing of cancer death in Taiwan. Currently, the treatments for colorectal cancer mainly use surgical resection to remove the cancer and combine different chemotherapy. Hence, there are many side effects caused by chemodrugs, including organ damage. However, under current treatment almost half of the colorectal carcinoma patients relapse within 5 years and inevitably succumb to the disease. Therefore, it needs to develop a new anti-cancer agent for colorectal cancer therapy. In previous study of our laboratory, using a drug screening system to find out Pogostemon patchouli (PPa) and Cedrus atlantica (CAt) had more efficiency to suppress colorectal cancer cell growth. Therefore, we used PPa and CAt crude extract, and PAO and Cedrol these two pure compounds in this study. The purpose is to investigate the anti-cancer mechanisms of PPa, CAt, PAO and Cedrol on colorectal cancer in vitro and in vivo. The results showed that PPa, CAt, PAO and Cedrol could inhibite colorectal cancer cell growth, induce cell cycle arrest at G0/G¬¬1 phase and G2/M phase, trigger extrinsic and intrinsic cell apoptosis pathway resulting cell death. In addition, it was also inhibition angiogenesis and metastasis in vitro. In animal study, the data showed that PPa and CAt could suppresse tumor growth and prolong animal survival time. In conclusion, those four drugs could induce cell cycle arrest, tumor cell apoptosis, anti-angiogenesis and anti-metastasis in vitro and in vivo. Finally, those drugs have highly potential to develop for anti-cancer agent in colorectal cancer therapy.

並列關鍵字

Colorectal cancer ； Pogostemon patchouli ( PPa) ； Cedrus atlantica (CAt) ； Patchouli alcohol (PAO) ； Cedrol

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