薏仁麩皮乙醇萃取物乙酸乙酯區分層對於人類乳癌細胞生長之影響

Effects of ethyl acetate fraction from adlay bran ethanolic extract on the growth of human breast cancer cell

徐志穎(Chih-Ying Hsu)

指導教授 ： 江文章

國立臺灣大學/生物資源暨農學院/食品科技研究所/碩士(2010年)

https://doi.org/10.6342/NTU.2010.00048

摘要

乳癌的發生率在台灣女性好發癌症中已躍居第一位，乳癌的發生跟雌二醇(estradiol，E2)的表現有很大的關係，而植物固醇(phytosterol)具有調節體內雌激素表現與抑制癌細胞增生的功效。故本研究擬探討薏仁麩皮乙醇萃取物對於人類乳癌細胞增生的影響，並比較不同樣品中植物固醇的含量與其抑制乳癌細胞增生作用是否相關。以開放式管柱層析配合不同溶劑沖提將薏仁麩皮乙醇萃取物依極性分成四個部分，並對不同乳癌細胞進行生長抑制分析。實驗結果顯示，低極性的部分對於乳癌細胞MCF-7有最佳的抑制效果，且對於正常乳腺上皮細胞H184B5F5/M10無顯著毒性；以流式細胞儀分析細胞週期的變化，發現乳癌細胞MCF-7經100 μg/ml濃度的萃取物分別處理不同時間後， G0/G1 phase的比例由40％上升至59％，在處理16小時後則有顯著的subG1 phase出現；以annexinV-PI雙染法分析，結果顯示癌細胞經處理6小時後，早期凋亡的癌細胞比例由5.4％
上升至51％；以西方轉漬法分析p53與p21蛋白的表現，結果發現隨著處理時間增加，萃取物能提高p53與p21的表現；針對各樣品以LC-MS/MS分析其植物固醇的含量，初步發現樣品中campesterol的含量與對乳癌細胞的抑制效果呈現正相關，推測薏仁麩皮萃取物中的植物固醇可能是抑制乳癌細胞增生的主要活性成分之一。

關鍵字

乳癌 ； 雌激素 ； 植物固醇 ； 細胞凋亡 ； p53

並列摘要

In Taiwan, breast cancer is one of the most common malignancies in women. Epidemiological studies pointed out that female exposed to estrogen abnormally increased the incidence of breast cancer. However, phytoestrogen, a plant chemical with known estrogenic effects, can lower breast cancer risk. Phytosterols, a kind of phytoestrogens, including β-sitosterol and campesterol have anticancer and regulate the ability for estrogen expression. Adlay, an annual crop, has been reported with many health effect including anticancer. Previous researches indicated that many kinds of phytosterol exist in adlay bran. Therefore the aim of this study is to investigate if the extracts from adlay bran can sufficiently inhibit the growth of human breast cancer cells.
The results show that low polarity of adlay bran extract not only exhibited the most potential on inhibiting proliferation of breast cancer cell, MCF-7. But also shown non-toxicity to normal mammary epithelial cell, H184B5F5/M10. The flow cytometry was used to analyze cell cycle distribution. In the beginning, the 100 μg/ml extract could increase the probability of MCF-7 arrest at G0/G1 phase from 40% to 59%. After treating 16 hours, an obviously proportion of cells appeared in the sub-G1 phase. Apoptosis were detected by annexinV-PI stain. Treating MCF-7 with 100 μg/ml effective sample for 6 hours, the apoptosis percentage is 10 fold higher than untreatment group. Western blotting was used to detect several different protein expression.The results show that the express of p53 and p21 in breast cancer cell can be enhanced with treating extracts by increasing treat time. The amounts of phytosterols in different samples were quantified by LC-MS/MS. The analytical results shown that the amount of campesterol in extracts have positive relationship with their anticancer effect.
In conclusion, the low polarity of adlay bran extract induce apoptosis of MCF-7. Phytosterols in adlay bran can be active compounds to inhibit breast cancer cell proliferation.

並列關鍵字

breast cancer ； apoptosis ； phytosterols ； estrogen ； p53

參考文獻

江文章、徐明麗、蘇瑞斌、龐飛。2000。薏仁加工食品輔助抑制腫瘤功效之評估。醫護科技學刊 2:113-122。

施純光。2004。薏仁對大腸癌形成之影響。國立臺灣大學食品科技研究所博士論文。台北。

林靜慧。2007。薏苡籽實乙醇萃取物及其次區分層對人類癌細胞生長之影響。國立臺灣大學食品科技研究所博士論文。台北。

李明怡。2008。薏仁麩皮中防癌及抗發炎活性成分之分離與鑑定。國立臺灣大學食品科技研究所博士論文。台北。

行政院衛生署。2008。台灣地區死因統計結果摘要及衛生統計。