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標題: | 牛樟芝抗癌機制研究 Studies on anticancer mechanisms of Antrodia cinnamomea |
作者: | Dai-Hua Tsai 蔡黛華 |
指導教授: | 李昆達(Kung-Ta Lee) |
關鍵字: | 牛樟芝,抗癌機制,大腸癌,細胞自噬,白色牛樟芝,菌種鑑定,培養條件優化, A. cinnamomea,anticancer mechanisms,colorectal cancer,autophagy,white A. cinnamomea,species identification,culture condition optimization, |
出版年 : | 2019 |
學位: | 博士 |
摘要: | 牛樟芝被稱為森林的紅寶石,是一種僅生長於台灣牛樟樹上的真菌,數百年來被當成原住民傳統草藥用來治療酒後不適、腹瀉及高血壓等疾病。研究顯示,牛樟芝具有抗發炎、免疫調節、肝保護、抗氧化及抗癌功能。本論文第一章在驗證牛樟芝之抗大腸癌功效,並進一步探討其抗癌分子機制。研究結果顯示,牛樟芝對 HCT116、HT29、SW480、Caco-2 及 Colo205 等 5 株大腸癌細胞皆具抑制生長效果;全基因表現圖譜顯示,以牛樟芝萃取物處理 HCT116 細胞後,會增加 HCT116 細胞中內質網壓力標記 CHOP 及其下游 TRB3 的基因表現,且其 Akt 及 mTOR 的磷酸化會受到抑制,進而造成細胞自噬性死亡,而抑制 CHOP 及 TRB3 基因表現則可反轉上述現象。裸鼠動物實驗結果則證實,牛樟芝可有效抑制 HCT116 腫瘤生長。本論文第二章著重在白色牛樟芝的鑑定、培養條件優化及活性探討,白色牛樟芝於野外被發現及分離,但其生長速度較一般牛樟芝慢,菌種未被鑑定,且藥理活性不明。由核醣體 DNA 序列分析顯示:白色牛樟芝與牛樟芝之序列相似度達 99 %,可判定為同一種物種。使用培養基 mPDA+mMEA 可顯著增加白色牛樟芝重量達 28 %,以低溫刺激、製造傷口及光線刺激皆能有效增加白色牛樟芝酒精萃取率,而製造傷口也可顯著增加白色牛樟芝重量。牛樟芝和白色牛樟芝萃取物的 HPLC 指紋圖譜顯示兩者化學組成成分不盡相同,在抗癌表現上也可見差異:兩者對5 種癌細胞都有抗癌功效,但白色牛樟芝對肝癌及肺癌細胞的抗癌效果比牛樟芝更強。本論文發現牛樟芝乃是透過 CHOP/TRB3/Akt/mTOR 路徑,引起細胞自噬性死亡以達抗大腸癌之功效,並確認白色牛樟芝的確與牛樟芝為同一品種,也首次證實其抗癌功效並優化白色牛樟芝的培養條件。本論文第三章收集並討論各種已發表之人工培養牛樟芝的方法,並比較其優劣,我們相信牛樟芝於藥物開發上具備強烈潛力。 Antrodia cinnamomea (also known as Antrodia camphorata), famed as “the ruby of the forest” in Taiwan, is a rare mushroom that grows only on the native Taiwanese tree Cinnamomum kanehirai. A. cinnamomea has been used in traditional medicine for hundreds of years to treat discomforts caused by alcohol consumption, diarrhoea, and hypertension. Several researchers have reported on the different biological activities of A. cinnamomea, such as anti-inflammatory and immunomodulatory effects, hepatoprotective activities, antioxidant activities, and anticancer activities. We wanted to uncover novel mechanisms of A. cinnamomea in colorectal cancer. The aims in chapter 1 were to examine whether A. cinnamomea can help fight against colorectal cancer and identify the molecular mechanisms underlying its anticancer activity. A. cinnamomea extracts showed cytotoxicity on HCT116, HT29, SW480, Caco-2 and, Colo205 colorectal cancer cells. Whole-genome expression profiling of A. cinnamomea extracts in HCT116 cells was performed. A. cinnamomea extracts upregulated the expression of the endoplasmic reticulum stress marker CHOP and its downstream gene TRB3. Moreover, dephosphorylation of Akt and mTOR as well as autophagic cell death were observed. Gene expression and autophagic cell death were reversed by the knockdown of CHOP and TRB3. Finally, we demonstrated that A. cinnamomea extracts significantly suppressed HCT116 tumour growth in nude mice. The focus of chapter 2 is white A. cinnamomea. The white variant of A. cinnamomea was observed in natural environments. However, white A. cinnamomea grew slower than A. cinnamomea. The pharmacological activity of white A. cinnamomea still remains unknown. The aims in this part were to identify the white A. cinnamomea strain, increase the total yield of white A. cinnamomea and examine whether white A. cinnamomea can help fight against cancer. The ribosomal DNA sequence data of A. cinnamomea and white A. cinnamomea suggested that the two strains used in this study are of the same species, A. cinnamomea. The special culture media composition, mPDA+mMEA, significantly increased the average weight of white A. cinnamomea by 28%. All of the stimuli, namely low-temperature stimulus, wound treatment, and light stimulus, can improve the ethanol extraction rate and wound treatment also increased the average weight of white A. cinnamomea. The HPLC chemical fingerprinting revealed that the chemical composition of A. cinnamomea and white A. cinnamomea are different, they may have significantly different biological actions and activities. Both two strains of A. cinnamomea have anticancer effects on five cancer cell lines. White A. cinnamomea even showed stronger cytotoxicity than A. cinnamomea in Huh7 and A549 cancer cells. Our findings suggest that autophagic cell death via the CHOP/TRB3/Akt/mTOR pathway may represent a new mechanism of anti-colorectal cancer action by A. cinnamomea. Our data also proved that white A. cinnamomea belongs to A. cinnamomea, provided an optimized culture condition of white A. cinnamomea, and suggested that white A. cinnamomea is a new potential anticancer drug. In chapter 3, we introduced and compared the traits of different artificial culture methods. From this study, we believe that A. cinnamomea possess strong capability in pharmaceutical drug development. |
URI: | http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/73450 |
DOI: | 10.6342/NTU201900695 |
全文授權: | 有償授權 |
顯示於系所單位: | 生化科技學系 |
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