銀杏萃取物與/或柴胡皂苷 a 對 HA22T/VGH 肝癌細胞增殖與凋亡的影響

Effects of Ginkgo biloba extract and/or saikosaponin a on proliferation and apoptosis in HA22T/VGH cells

何欣蓉(Hsin-Jung Ho)

指導教授 ： 趙振瑞

臺北醫學大學/公共衛生暨營養學院/保健營養學研究所/碩士(2011年)

摘要

肝癌為全球最常見的癌症之一，且占全球癌症死因第三位。銀杏與柴胡為我國傳統醫學中重要的中草藥，先前研究證實銀杏萃取物 (EGb 761) 具有抗氧化、改善血液循環及抑制癌細胞增殖的特性；而柴胡皂苷 a (saikosaponin a, SSa) 為柴胡根部萃取物具生理活性之主要成分之一，研究也證實其具有抗發炎、護肝、抗癌及抗病毒的作用，但目前仍鮮少有研究深入探討 EGb 761 和/或 SSa 對肝癌之影響。因此，本次研究以源於亞裔男性之肝癌細胞株 (HA22T/VGH) 作為體外實驗模式，添加不同濃度的 EGb 761 (0-500μg/mL) 或/和 SSa (0-10μg/mL) 24 小時後，測量其細胞增殖情形、細胞毒性分析、類胰島素生長因子 (insulin-like growth factor-II, IGF-II) 與轉化生長因子-α (transforming growth factor-α, TGF-α) 之表現量及細胞凋亡相關蛋白質表現量，包括：cytochrome c、caspase-3、Bax 及 Bcl-2 。結果顯示 EGb 761 (250 μg/mL 及 500 μg/mL)、SSa (7.5 μg/mL 及 10 μg/mL) 和兩者合併組(250 μg/mL EGb 761 + 7.5 μg/mL SSa 及 500 μg/mL EGb 761 + 7.5 μg/mL SSa ) 可以抑制 HA22T/VGH 人類肝癌細胞增殖，降低腫瘤發展指標— IGF-II 與 TGF-α 表現量，並可能是藉由抑制 Bcl-2 蛋白質表現量，及增加 cytochrome c 及 caspase-3 蛋白質表現量，而誘導肝癌細胞凋亡。且以 250 μg/mL EGb 761 與 7.5 μg/mL SSa 合併培養的組別以及 500 μg/mL EGb 761 與 7.5 μg/mL SSa 合併培養的組別，分別對於抑制癌細胞增殖效果及增加 caspase-3 蛋白質表現量大於單獨培養，具有加乘的作用。EGb 761 及 SSa 可以顯著抑制肝癌細胞增殖並誘導細胞凋亡，未來可能運用於抗肝癌治療上。

關鍵字

肝癌 ； 銀杏萃取物 ； 柴胡皂苷a ； 細胞凋亡

並列摘要

Hepatocellular carcinoma (HCC) is one of the most common cancers in the world, and is the third leading cause of cancer death worldwide. Ginkgo biloba extract (EGb 761) possesses antioxidant, antiplatelet activating, and antiproliferating properties. Saikosaponin a (SSa), as a principal active ingredient in the root of Bupleuri Radix, exhibits antiinflammatory, hepatoprotective, antitumoral, and antiviral activities. However, very few studies have further determined the effect of EGb 761 and/or SSa on HCC. The study investigated the effects of EGb 761 and SSa on carcinogenesis and apoptosis in HCC cells. Various concentrations of EGb 761 (0-500 μg/mL) and/or SSa (0-10 μg/mL) were added in the medium of HA22T/VGH cell line, which was Asian male origin, for 24 hours. Cell proliferation, insulin-like growth factor-II (IGF-II), transforming growth factor-α (TGF-α), and apoptosis-related protein expression, such as cytochrome c, caspase-3, Bax, and Bcl-2, were measured. EGb 761 and SSa significantly inhibited cell proliferation of HA22T/VGH cells at the concentrations of 250-500 μg/mL and 7.5-10 μg/mL, respectively. The secretion of IGF-II and TGF-α, biomarkers for tumor progression, was tended to be suppressed by the addition of EGb761 and/or SSa to HA22T/VGH cells. Furthermore, EGb 761 and/or SSa induced apoptosis via inhibiting Bcl-2 expression and stimulating protein expression of cytochrome c and caspase-3. The combination of 250 μg/mL EGb 761 and 7.5 μg/mL SSa and the combination of 500 μg/mL EGb 761 and 7.5 μg/mL SSa had the synergistic effects on down-regulating cell proliferation in HA22T/VGH cells and up-regulating protein expression of caspase-3, respectively. EGb 761 and/or SSa significantly and synergistically inhibited cell proliferation and induced caspase-3 protein of HCC cells, and can be considered as possible anti-HCC agents.

並列關鍵字

hepatocarcinogenesis ； Ginkgo biloba extract ； saikosaponin a ； apoptosis

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