褪黑激素藉由造成細胞週期G1期停滯進而抑制人類卵巢癌腫瘤細胞活性

The Anti-Tumorigenic Activity of Melatonin in Human Ovarian Cancer Cell lines through Cell Cycle G1 Arrest Induction

陳苡秭(Yi-Tz Chen)

指導教授 ： 徐怡強

長榮大學/健康科學學院/醫學研究所/碩士(2016年)

摘要

多年來國人十大疾病死亡之首為惡性腫瘤。尤其是女性癌症 （乳癌、子宮體或子宮頸癌、卵巢癌輸卵管及寬韌帶癌等等） 就佔了所有癌症中的36.5%，每年奪走接近四萬人的生命，影響龐大的社會資源損失和醫療費用支出。
褪黑激素 （Melatonin） 是腦內松果腺體 （Pineal Gland） 所製造的天然荷爾蒙，分泌量在夜間睡眠時最大、白天最小。它每天分泌量的消長控制著人體清醒與睡眠的周期。多年來專家建議補充褪黑激素幫助睡眠及調整時差，最近研究發現，褪黑激素可能具有癌症化學治療的作用。我們初步探討褪黑激素對卵巢癌細胞株的影響，利用MTT assay 測試細胞增殖以及劑量依賴性，經褪黑激素加藥處理人類卵巢癌細胞24 小時後，觀察到明顯的劑量依賴性而導致細胞生長停滯，並利用流式細胞儀配合 Propidium Iodide 染劑測試經褪黑激素處理後細胞週期的變化，以及利用Propidium Iodide 與 Annexin V 雙染劑的染色方法觀察是否有細胞凋亡與壞死，實驗結果發現人類卵巢癌細胞經褪黑激素處理後造成細胞週期 G1期停滯，且褪黑激素並非造成人類卵巢癌細胞的細胞凋亡與壞死來達成抑制腫瘤生長的機制，因此進而利用西方墨點法 （Western blotting） 檢測與G1期相關的蛋白質，結果表明，透過抑制CDKs以及Cyclins蛋白質的表現量為造成細胞週期停滯於G1期之主要原因，但是對於卵巢癌的預防與治療機轉仍不明確，因此本論文探討褪黑激素成為有效的抗癌藥物之可行性，同時探討其對於卵巢癌之抑癌作用機轉與細胞週期及癌化、抑癌化基因蛋白質表現之調控方式。然而，希望褪黑激素可以提供一個新的機制來預防以及治療癌症。

關鍵字

卵巢癌 ； 褪黑激素 ； 細胞週期 ； G1期停滯

並列摘要

Malignant tumors are the leading cause of death in Taiwan. Cancers, including those of breast, uterus, cervix, fallopian tube, broad ligament, and ovaries, that affect females account for 36.5 % of all cancers. These cancers cause four million deaths per year and have a large financial and social impact.
　　Melatonin, a hormone synthesized by the pineal gland, controls sleep and wake cycles. Normally, melatonin levels increase in the mid to late evening, remain high for most of the night, and then drop in the early hours of the morning. Recent studies have found that melatonin may have effects similar to those of cancer chemotherapy.
In the present study, we investigated the anticancer effects of melatonin in three human ovarian cancer cell lines (PA-1, Hey-A8, and OVCAR-429 cells). We measured cell proliferation 24 h after melatonin treatment using the MTT assay. Consequently, melatonin was found to affect cell proliferation in a dose-dependent manner, eventually leading to cell growth arrest. Next, we analyzed the cell cycle using the propidium iodide staining and apoptosis using propidium iodide/annexin V double staining. Melatonin arrested the cell cycle in the G1 phase but did not induce apoptosis or necrosis.
The best methods for preventing and treating ovarian cancer remain undefined. In this study, we investigated the role of melatonin in tumor suppression and cell cycle regulation in ovarian cancer. Our findings indicate that melatonin may represent a new direction for the prevention and treatment of cancer.

並列關鍵字

ovarian cancer ； melatonin ； cell cycle ； G1 arrest

參考文獻

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