百里醌誘導口腔癌細胞自體吞噬與細胞凋亡之機制探討

Thymoquinone induces autophagy and apoptosis in oral cancer cells

賴奕曄(Yi-Yeh Lai)

指導教授 ： 謝易修 ； 陳霈霓

中山醫學大學/醫學院/生化暨生物科技研究所/碩士(2013年)

https://doi.org/10.6834/CSMU.2013.00003

摘要

百里醌是從果黑種草(Nigella sative)的種籽中萃取出來的化合物，在回教醫學中是一種常用藥材。在最近的研究中指出，百里醌在癌細胞增生、轉移和腫瘤血管新生有抑制的作用。然而，百里醌在頭頸部鱗狀細胞癌(HNSCC)的影響，至今仍不清楚。在本篇研究中，我們證實了百里醌對SASVO3（高度惡化的頭頸部鱗狀癌細胞株，從原位腫瘤連續移植三次）引發了強烈的毒殺作用，隨著處理藥物濃度增加，細胞的毒殺性也隨之增加。SASVO3細胞處理百里醌後，Bax和cleaved-caspase 7及9的蛋白表現量增加，證明百里醌會誘導細胞凋亡。另一方面，利用AVO stain assay，細胞處理百里醌後，觀察到自噬囊泡(autolysosome)的增加，此外，這些細胞自噬的特定標記物， LC3-I、LC3-II蛋白表現量也明顯增加，而Bcl-2，Bid，PARP，Akt和mTOR這些細胞自噬與細胞凋亡相關蛋白的表現量，也受到百里醌處理後下降。綜觀上述研究結果，百里醌透過誘導細胞凋亡和細胞自噬這兩種不同抗腫瘤途徑的機轉引發口腔癌細胞死亡。綜合以上，百里醌誘導口腔癌細胞死亡的機轉，在未來或許可應用在植物化學預防及癌症治療。

關鍵字

百里醌口腔癌 ； 細胞自體吞噬 ； 細胞凋亡

並列摘要

Thymoquinone (TQ) is a phytochemical compound extracted from the plant Nigella sative, one in Islamic medicine commonly used herbs. Recent studies reported that TQ exhibited inhibitory effects on cell proliferation, migration, and tumor angiogenesis in various cancer cell lines. However, the effects of TQ on anti-cancer properties in head and neck squamous cell carcinoma (HNSCC) remain unclear. In this study, we demonstrated that the TQ induced a strong cytotoxic effect toward a highly malignant HNSCC cell line, SASVO3, from primary tumors using three sequential rounds of xenotransplantation. The mechanisms of the cytotoxic effect were concentration-dependent. TQ induced apoptotic cell death in SASVO3 cells, as evidenced by increases in the expression of Bax and activation of caspase-7 and -9. On the other hand, these cells showed increased levels of autophagic vacuoles and LC3-I and LC3-II protein expression, specific markers of autophagy. The levels of Bcl-2, Bid, PARP, Akt, and mTOR, which have been implicated in the down-regulation of autophagy and induction of apopotosis, were decreased upon TQ treatment. Taken together, these findings indicate that TQ induced cell death in oral cancer cells via two distinct antineoplastic activities, the ability to induce apoptosis and autophagocytosis, and TQ represent promising candidates for future phytochemical-based mechanistic pathway-targeted cancer prevention strategies.

並列關鍵字

Thymoquinone ； oral cancer ； autophagy ； apoptosis

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