探討歐洲杉醇抗藥性攝護腺癌細胞中EGFR和IL-8調控轉移之分子角色

Molecular role of EGFR and interleukin-8 related migration in docetaxel-resistant prostate cancer cells

張喜雯(Hsi-Wen Chang)

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

在臨床上，治療賀爾蒙抗性攝護腺癌患者（CRPC）第一線藥物為docetaxel，docetaxel有效地增加患者存活率，然而，當癌細胞對docetaxel產生抗藥性時，治療效果將變得非常有限。因此，對於docetaxel抗藥性的研究非常重要且迫切。過去研究文獻指出，EGFR和IL-8通過訊息傳遞調控攝護腺癌發展和抗藥性，但在攝護腺癌細胞中EGFR和IL-8與轉移相關分子機轉尚未完全被釐清。本篇研究目的是探討docetaxel抗藥性攝護腺癌細胞中，EGFR和IL-8與轉移相關之分子機制，並尋找未來針對docetaxel抗性之轉移性CRPC可能的治療策略。本實驗室已建立PC3細胞對docetaxel具耐受性之細胞PC/DX25。本研究中利用細胞轉移實驗初步發現，PC/DX25相較PC3轉移能力較強，利用Western blot觀察到PC/DX25相較PC3和其他攝護腺和攝護腺癌細胞，其EGFR、IL-8和CXCR1表現較高。利用重組蛋白EGF和IL-8處理細胞，會增加攝護腺癌細胞遷移能力、EGFR、p-EGFR（Y1068）、NF-κB p65和IL-8分子表現。反之，利用siRNA抑制EGFR和IL-8表現，會抑制攝護腺癌細胞遷移能力、EGFR、p-EGFR（Y1068）、NF-κB p65和IL-8分子表現。我們還發現抑制EGFR後細胞核內p-p38下降。Docetaxel處理PC3細胞後，誘導EGFR、p-EGFR和IL-8分子表現增加，IL-8啟動子活化程度和分泌量也增加。這些結果都證明了EGFR和IL-8分子是調控攝護腺癌細胞轉移的關鍵，通過EGFR/p-EGFR（Y1068）/NF-κB p65/ IL-8分子訊息傳遞路徑調控。綜合以上結果顯示，在抗藥性攝護腺癌細胞中，EGFR和IL-8訊息傳遞有調控轉移潛在作用，建議docetaxel合併使用EGFR和IL-8抑制劑來治療攝護腺癌，預防潛在的抗藥性和轉移性。

關鍵字

攝護腺癌 ； 歐洲杉醇抗藥性 ； 表皮生長因子受體 ； 細胞激素-8,

並列摘要

In clinical, docetaxel is used in the first-line treatment for patients with castration‑resistant prostate cancer （CRPC）, significantly extended overall survival of patients. However, the treatment is usually limited when gradual development of docetaxel-resistance. It has become imperative and important to find the mechanism of the docetaxel-resistance in prostate cancer. In previous studies have suggested that epidermal growth factor receptor （EGFR） and Interleukin-8 （IL-8） are required for prostate cancer progression and drug resistance. The molecular mechanism of how EGFR and IL-8 mediated migration in prostate cancer cells is still elusive. Thus, this study was aimed to investigate the molecular mechanisms of EGFR and IL-8 regulated migration in the docetaxel-resistant prostate cancer cells and to search the possible therapeutic strategies for docetaxel-resistant metastatic CRPC in future. We have established PC3 docetaxel-resistant cell line (PC/DX), PC/DX25 maintain in 25 nM docetaxel. We found that PC/DX25 metastatic developed faster than PC3 cellls, and expressed the higher protein levels of EGFR, IL-8 and CXCR1 than PC3 and Immortalized prostate cells. In this study, the cell migration, protein levels of EGFR, p-EGFR(Y1068), IL-8, NF-κB p65 and Epithelial-Mesenchymal Transition (EMT) were induced by the treatment with EGF and IL-8 recombinant proteins. In contrast, the cell migration, protein levels of EGFR, IL-8, NF-κB p65 and EMT were inhibited by the treatment with EGFR and IL-8 siRNA. And we also found that nuclear p-p38 was inhibited by the treatment with EGFR siRNA. Interestingly, the PC3 cells were induced EGFR and IL-8 protein levels by the treatment with docetaxel. We also found that treated the PC3 cells with docetaxel induced IL-8 promoter activative and IL-8 cytokine secretion. These results suggest that EGFR and IL-8 have key roles in regulation of the migration of docetaxel-resistant prostate cancer cells, and molecular mechanism of cell migration EGFR/p-EGFR（Y1068）/NF-κB p65/IL-8 signaling pathway. Our study revealed EGFR and IL-8 signaling pathway regulated cell migration in docetaxel-resistant prostate cancer cells, and suggested that combined EGFR and IL-8 inhibitor with docetaxel may used to treatment for prevention of potential drug-resistance and metastasis.

並列關鍵字

Prostate cancer ； docetaxel resistant ； EGFR ； IL-8

參考文獻

1. Kumar VL, Majumder PK. Prostate gland: structure, functions and regulation. International Urology and Nephrology 1995;27:231-43

2. Shang Y, Liu C, Cui D, Han G, Yi S. The effect of chronic bacterial prostatitis on semen quality in adult men: a meta-analysis of case-control studies. Scientific Reports 2014;4:7233

3. 2017 American Cancer Society. .

4. Health Promotion Administration, Ministry of Health and Welfare.

5. Hoffman RM, Gilliland FD, Eley JW, Harlan LC, Stephenson RA, Stanford JL, Albertson PC, Hamilton AS, Hunt WC, Potosky AL. Racial and ethnic differences in advanced-stage prostate cancer: the Prostate Cancer Outcomes Study. Journal of the National Cancer Institute 2001;93:388-95