探討腺苷單磷酸活化蛋白激酶 (AMPK) 調控攝護腺癌對歐洲杉醇抗藥性的分子機制

Molecular mechanisms of AMPK mediated docetaxel-resistance in human prostate cancer

侯佩伸(Pei-Shen Hou)

指導教授 ： 侯自銓

高雄醫學大學/醫學院/醫學研究所碩士班/碩士(2017年)

摘要

Docetaxel為治療賀爾蒙抗性攝護腺癌的第一線化療藥物，但不幸地，臨床上使用docetaxel會逐漸產生藥物抗藥性，腺苷單磷酸活化蛋白激酶 (AMPK) 為細胞能量感應器，AMPK調控細胞代謝作用其中包括糖解反應用以維持細胞能量平衡，我們發現在攝護腺癌中，AMPK表現和docetaxel抗藥性的發展有關，然而AMPK造成攝護腺癌發展成docetaxel抗藥性的作用機轉尚未釐清。在我們的研究結果中，利用Western blot分析發現PC/DX25抗藥株的p-AMPK (S487) 表現量比PC3細胞株高，以docetaxel處理PC3細胞株發現隨著藥物濃度增加，而p-AMPK (S487) 表現量隨之增加，接著利用MTT assay分析，發現抑制AMPK表現的PC/DX25抗藥株回復對docetaxel的敏感性，然而針對PC/DX25抗藥株給予AMPK促效劑2-Deoxy-D-glucose (2DG) 和5-Aminoimidazole-4-carboxamide ribonucleotide (AICAR) 反而增加了docetaxel的抗藥性。在PC/DX25抗藥株中也發現AMPK抑制HIF-1α與PFKFB4分子表現量，而抑制HIF-1α與PFKFB4分子表現可能有利於PC/DX25抗藥株的生存，在賀爾蒙抗性攝護腺癌 (CRPC) 臨床檢體中也發現p-AMPK (S487) 具有高度表現量。綜合以上結果，AMPK在具有docetaxel抗藥性攝護腺癌中可能扮演重要調控角色。

關鍵字

腺苷單磷酸活化蛋白激酶歐洲杉醇抗藥性 ； 攝護腺癌

並列摘要

Docetaxel is the first-line chemotherapeutic agent for patients with castration resistant prostate cancer (CRPC). Unfortunately, clinical treatment with docetaxel often encounters a number of undesirable side effects, including drug resistance. AMP-activated protein kinase (AMPK) is the cellular energy sensor, which can regulate metabolism and maintain energy homeostasis involving glycolysis. Recently, we found AMPK was associated with the development of docetaxel resistance in PC. However, the mechanisms of AMPK-mediated docetaxel-resistance in PC were remained unclear. Our results showed that the level of phospho-AMPK (S487) was significantly higher expression in PC/DX25 cells (a docetaxel resistance PC cell line) than in parental PC3 cells by Western blotting analysis. The expression of phospho-AMPK (S487) was gradually increased by docetaxel treatment in a dose-dependent manner in PC3 cells. Knockdown of AMPK expression reversed docetaxel sensitivity in PC/DX25 cells by MTT assay. However, using the AMPK agonist 2-Deoxy-D-glucose (2DG) and 5-Aminoimidazole-4-carboxamide ribonucleotide (AICAR) enhanced the docetaxel resistance in PC/DX25 cells. We also found the expression of HIF-1α and PFKFB4 were reduced via AMPK in PC/DX25 cells. Downregulation of HIF-1α and PFKFB4 were associated with PC/DX25 cell proliferation. The phospho-AMPK (S487) was overexpressed in clinical cancer samples of castration-resistant prostate cancer (CRPC). According to the above results, AMPK may play an important role in regulating chemoresistane in docetaxel-resistant prostate cancer.

並列關鍵字

AMPK ； docetaxel-resistance ； prostate cancer

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