山葵萃取物對結腸直腸癌細胞毒性之研究

Study of cytotoxicity of Wasabia japonica extracts on colon cancer cell

洪筱喻(Hsiao-Yu Hung)

指導教授 ： 周芬碧

中山醫學大學/醫學院/生化暨生物科技研究所/碩士(2010年)

https://doi.org/10.6834/CSMU.2010.00091

摘要

食用山葵的好處有很多，它可以增進食慾，促進腸胃的消化及吸收，抑制食物中的細菌及真菌。過去的研究指出山葵中的成分可以抑制癌細胞的增生。本研究顯示，山葵水萃物對於Caco-2 以及COLO 205 這兩株結腸直腸癌細胞有毒殺效果。為了確認細胞死亡的方式，進一步使用DAPI 染色和AVOs 染色來辨別。實驗結果顯示出在Caco-2 細胞以及COLO 205 細胞中發現DNA 濃染的情形，在COLO 205細胞中則有AVOs的形成，可以得知山葵萃取物主要會使細胞走向Apoptosis 。在分析COLO 205 細胞的細胞周期發現，低劑量的山葵萃取物會使細胞停留在G2/M 期。使用Annexin V-Fitc 以及PI 染色後以流式細胞儀做分析，證實高劑量的山葵萃取物則會使細胞走向在Apoptosis 。使用Real time PCR 分析與Apoptosis 和Autophagy 相關的基因mRNA表現量發現，山葵萃取物處理COLO 205細胞會使細胞走向Apoptosis 和Autophagy ，這兩種死亡型態會一併發生。並且我們發現某些基因會依照處理的山葵萃取物濃度不同而會有不同的表現量。此外在低劑量的山葵萃取物(100 μg/ml) 合併放射線有協同作用，增加對於細胞的毒殺效果。山葵萃取物在In vivo 的動物實驗中，單獨處理山葵萃取物無法抑制腫瘤的生長，合併了山葵萃取物與放射線後能夠延緩腫瘤生長的速度。綜合以上結果，本研究顯示出山葵有抑制結腸直腸癌效果，並且支持山葵成為化學預防功能性食品。

關鍵字

山葵萃取物 ； 結腸直腸癌 ； 細胞凋亡

並列摘要

Consumption of wasabi has many advantages such as increasing appetite, improving digestion and absorption and inhibiting bacteria and fungi in food. Previous research indicated that some components of wasabi can inhibit the proliferation of cancer cell. This study demonstrated the cytotoxic effect of wasabi (water extracts) on Coco-2 and COLO 205 cells. The results of DAPI and AVOs stains revealed that Caco-2 and COLO 205 cells both showed chromation condensation after wasabi treatment, and COLO 205 also formed AVOs, indicating that apoptosis was the major cell death mechanism caused by wasabi. Flow cytometry analysis demonstrated that low doses of wasabi (water extracts) induced growth arrest of COLO 205 cells at G2/M phase. High doses of wasabi, on the other hand, induced apoptosis of COLO 205 cells as evidenced by Annexin V and PI staining. Real time PCR analysis of the mRNA levels of apoptosis and autophagy related genes showed that both pathways were induced by wasabi extract in COLO 205 cells, and the expressions of some genes were dose-dependent to wasabi concentrations. Furthermore, a synergistic cytotoxic effect was observed when low dose of wasabi (100μg/ml) was combined with radiation. In nude mice experiment, wasabi alone did not suppress the growth of tumour. However, a combination of wasabi and radiotherapy delayed tumour growth significantly. Taken together, our studies demonstrate the anti-cancer function of wasabi in colorectal cancer and support the application wasabi as chemoprevention functional food.

並列關鍵字

Wasabi (water extracts) ； Colorectal cancer ； Apoptosis

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