椴木栽培牛樟芝子實體中三萜類活性成分Antcin K藉由調節Integrin所介導的細胞黏附、移行及侵犯，達到抑制人類肝癌細胞轉移之效果

Abstract

惡性腫瘤位居國人十大死因之首，肝癌更是國人十大癌症死因中的第二名。隨著肝癌之發展惡化，轉移是導致癌症病患死亡之主因。因此就台灣而言，如何預防肝癌並且抑制肝癌的轉移是一個值得重視的議題。有文獻指出牛樟芝子實體乙酸乙酯萃取物（EAC）能夠抑制人類肝癌細胞的侵犯能力，本實驗所使用的antcin K為牛樟芝子實體的主要活性成分，麥角甾烷型三萜類純化物中含量最高者，因此本研究之假說推測antcin K具有抑制人類肝癌細胞轉移的功效。本研究目的為評估antcin K抑制人類肝癌細胞轉移之效果及其機制探討。結果顯示在antcin K的處理下，可顯著降低Hep 3B細胞黏附於細胞外基質的作用以及移行和侵犯的能力，並且可以降低Hep 3B細胞內基質金屬蛋白酶─2（MMP-2)和基質金屬蛋白酶─9（MMP-9)的蛋白質表現量以及其分泌活性，並促使Hep 3B細胞中上皮細胞指標蛋白E-cadherin表現量上升，而間質細胞指標蛋白vimentin表現量下降。更深入探討其相關分子機制發現，antcin K可以降低Hep 3B細胞內Integrin β1、β3、α5及αv的蛋白質表現量，並且抑制FAK、Src、PI3K、AKT、MEK、ERK及JNK蛋白質的磷酸化。綜合以上結果推測antcin K可能是藉由降低細胞中Integrin β1、β3、α5及αv的蛋白質表現量及FAK的活化，並且抑制下游PI3K/AKT、MEK/ERK及JNK訊息傳遞途徑的活化，進而降低細胞的MMP-2和MMP-9蛋白質表現量以及其分泌活性，同時影響上皮─間質轉化（epithelial-mesenchymal transitions, EMT)，最後達到抑制人類肝癌細胞轉移的效果。本研究結果指出椴木栽培牛樟芝子實體中麥角甾烷三萜類活性成分antcin K具有降低肝癌轉移風險的潛力，期待其將來能作為抑制癌細胞轉移和輔助抗癌治療之參考。

In Taiwan, cancer ranks the first of the ten leading causes of death. The statistic of 2013 published by Ministry of Health and Welfare, Executive Yuan, Taiwan showed that liver cancer was the second leading cause of cancer related deaths. However, more than 90% of cancer patients die not from their primary tumors but due to the development of metastasis. Therefore, how to prevent liver cancer and reduce cancer metastasis is a big issue in Taiwan. Previous researches demonstrated that the ethyl acetate extract from Antrodia cinnamomea suppresses the invasive potential of human hepatoma cells. The main active ingredients of Antrodia cinnamomea is ergostane-type triterpenoids, and the content of antcin K is the highest. Thus, the hypothesis of this study is that antcin K could suppresses the metastatic potential of human hepatoma cells. And the objective is that evaluating the anti-metastatic activity and mechanisms of antcin K, which is purified from the fruiting body of basswood cultivated Antrodia cinnamomea on human liver cancer cell line Hep 3B. The results show that adhesion, migration and invasion of Hep 3B cells were effectively inhibited by antcin K within 24 hours. In addition, antcin K not only reduced the protein expression and activity of MMP-2 and MMP-9, but also down-regulated vimentin, and up-regulated E-cadherin in Hep 3B cells. In depth investigation for the molecular mechanisms, revealed that antcin K could reduce the protein expression of integrin β1, β3, α5 and αv, and suppress phosphorylation of FAK, Src, PI3K, AKT, MEK, ERK and JNK. These results suggested that antcin K is able to inhibit the metastasis of human hepatoma cells through suppression of integrin-mediated adhesion, migration, and invasion. Coupled with these findings, antcin K has the good potential to reduce the risk of liver cancer metastasis.