| 摘要: | 肺癌目前已是台灣癌症病人死亡的主要原因之一，而肺癌細胞轉移(metastasis) 是肺癌導致死亡以及治療複雜度提昇的主要原因。而癌細胞的轉移已知與多種細胞生理改變密切相關，如改變癌瘤細胞與胞外基質(extracellular matrix，ECM)間adhesion 的能力，破壞細胞間交互作用(intercellular interaction) 的力量等。癌瘤細胞之所以能轉移主要是透過癌瘤細胞分泌蛋白分解酵素如serine proteinases，metalloproteinases (MMPs) ，cathepsins 以及
plasminogenactivator (PA) 分解ECM，最後導致intercellular matrix 分離，進而使癌瘤細胞motility、migration 及invasion 提昇。而本實驗室在 94年度衛生署的中醫藥研究計畫-中藥抑制癌瘤細胞遷移和侵犯作用之系統分析研究-篩選了 57種中藥，發現其中有 6種中藥粗萃取物不會抑制肺 癌細胞株的生長能力，卻可以有效抑制肺癌腫瘤細胞的侵襲及轉移。而我們更進一步利用動物模式，發現這 6種中藥有卷柏 (Selaginella tamariscina)、欖仁樹的葉 (Terminalia catappa L. leaves)及紫花地丁 (Viola yedoensis) 這 3種中藥粗萃取物可以有效抑制接種在動物身上腫瘤的大小及轉移。首先，選取人類肺癌細胞A549 及老鼠肺癌細胞LLC 探討欖仁樹葉、卷柏及紫花地丁的萃取物 (TCE, STE, and VYE)抑制癌細胞侵襲轉移的效果。結果發現：欖仁樹葉、卷柏及紫花地丁不會影響A549 細胞的存活，但會降低LLC 的細胞存活，然而對A549 及LLC細胞的侵襲及移動能力則都具有極顯著的抑制效果。進一步分析與癌症轉移息息相關的蛋白水解酶(MMPs and u-PA)的活性，發現TCE, STE, and VYE 在A549 細胞或是LLC 細胞中，都會抑制細胞所分泌之MMP 或是u-PA 之ㄧ或同時抑制兩者的活性。然而在分析TIMP-2 及PAI-1(MMP-2 及u-PA 的內生性抑制劑)時，卻只有STE 可以明顯增加TIMP-2及PAI-1 的蛋白表現。進行完整的動物模式試驗證實TCE 及STE 的確可以抑制肺癌細胞在活體內的生長及轉移。此外，也完成了TCE 及STE 的HPLC-mass spectrometry 分析。綜合以上發現，卷柏(Selaginella tamariscina)、欖仁樹的葉 (Terminalia catappa L. leaves) 及紫花地丁 (Viola yedoensis) 這 3 種中藥粗萃取物可有效抑制肺癌細胞的增生及侵襲的能力，因此，或許可作為控制肺癌轉移的輔助治療。
Lung cancer has been the leading cause of cancer death in Taiwan for over a decade.Metastasis of cancer cells, a multiple and intricate process, may complicate the clinical
management and lead to a poor prognosis with tremendous impact to patients or communities. In general, metastasis of cancer cells involves multiple processes and various cytophysiological
changes, including changed adhesion capability between cells and extracellular matrix (ECM) and damaged intercellular interaction. Degradation of ECM by cancer cells via protease, such as
serine proteinases, metalloproteinases (MMPs), cathepsins, and plasminogen activator (PA), may lead to the separation of intercellular matrix to promote the mobility of cancer cells and
eventually lead to metastasis.In our preliminary study, a lung cancer cell line, A549, has been treated with 57 Chinese herbal
medicines and then subjected to an assay for cell viability or invasion, and results showed that 6 Chinese herbal medicines was significantly inhibited on cell migration and invasion. Further, to use the animal model to evaluate the impacts by the addition of 6 Chinese herbal medicines and
results showed that 3 Chinese herbal medicines including Terminalia catappa L. leaves extract
(TCE), Selaginella tamariscina extract (STE) and Viola yedoensis extract (VYE) were
significantly inhibited the tumor growth and metastasis.In this project, despite influence on cell viability, TCE, STE, and VYE markedly inhibited the invasion and motility of A549 cells and LLC cells in the rage of 10-100 μM. As MMPs and u-PA play a critical role in cancer cell metastasis, we also found that TCE, STE, and VYE could inhibit MMPs or u-PA activities at least one of them or both of them in A549 cells and LLC cells.However, only STE could significantly induce the expression of TIMP-2 and PAI-1 (endogenous
inhibitor of MMP-2 and u-PA), whereas TCE and VYE showed lowering or no effect. Consist with the preliminary animal experiment, the complete animal experiments definitely showed that TCE and STE have the anti-tumor growth and anti-metastatic potentials. In addition, the HPLC-mass spectrometry analysis of TCE and STE has also been done. In conclusion, TCE, STE and VYE perturb the invasion capacities of lung cancer cells,thereby constituting an adjuvant treatment for metastasis control. |
