白藜蘆醇對鼻咽癌中基因的異常甲基化及細胞移動的影響

Effects of resveratrol on aberrant gene methylation and cell migration in nasopharyngeal carcinoma

林嘉程(Jia-cheng Lin)

指導教授 ： 劉阜果

國立中央大學/理學院/生命科學系/碩士(2014年)

摘要

白藜蘆醇是一種天然植物多酚，它可以影響多種調控途徑去影響癌症細胞，例如透過細胞凋亡的機制促使癌症細胞死亡，或者透過抑制癌細胞的增生。但對於白藜蘆醇是否可以降低鼻咽癌細胞中腫瘤抑制基因的異常甲基化以及是否可以降低鼻咽癌細胞移動能力，我們還不是非常地清楚。在此我們先將四種鼻咽癌細胞株TW-04、TW-076、HK-1和C666-1處理不同濃度的白藜蘆醇後發現，當濃度超過100 μM時，會有明顯的細胞毒殺現象；但同樣情況下對正常鼻咽細胞NP-69並沒有毒殺現象。接著，我們透過Methylation-specific PCR來分析RASSF1A、DAPK1、RARβ2和MGMT這四種腫瘤抑制基因在鼻咽癌細胞株中異常甲基化的情形，並比較施予白藜蘆醇於鼻咽癌細胞株對基因甲基化的影響。結果發現這四個基因在鼻咽癌細胞株皆具有異常甲基化的情形，而在給予白藜蘆醇後，發現對不同鼻咽癌細胞株有不同去甲基化的影響。而透過Boyden’s chamber migration assay以及傷口癒合試驗(wound-healing assay)，並發現當TW-04、TW-076、HK-1和C666-1鼻咽癌細胞株給予50 μM白藜蘆醇後，其細胞移動能力分別下降37%、78%、62.5% 以及86%。我們的結果顯示，白藜蘆醇可以降低異常基因甲基化的程度，且可以抑制鼻咽癌細胞株的移動能力。以上結果，證實白藜蘆醇是具有潛力成為一個治療鼻咽癌的藥物，並在抑制鼻咽癌轉移有不錯的結果。

關鍵字

鼻咽癌 ； 甲基化 ； 白藜蘆醇 ； 細胞移動 ； 腫瘤抑制基因

並列摘要

Resveratrol, a naturally dietary compound, has been reported that it affected
many pathways to cause apoptosis or to inhibit cell proliferation in various cancers. But we were not sure about the effects of resveratrol on aberrant hypermethylation levels of tumor suppressor genes and cell motility in nasopharyngeal carcinoma (NPC). First, we treated four NPC cell lines, TW-04, TW-076, HK-1 and C666-1 with various concentrations of resveratrol. This resulted in significant decrease in cell viability when the concentration of resveratrol was equal or higher than 100 μM. On the other hand, resveratrol treatment didn’t cause cell death in normal cells, NP-69. Next, we studied RASSF1A, DAPK, RARβ2 and MGMT methylation statuses in NPC cell lines by methylation-specific PCR (MSP), and compared them with those in resveratrol treated NPC cell lines. The aberrant hypermethylation of RASSF1A, DAPK, RARβ2 and MGMT was detected in all NPC cell lines (TW-04, TW-076, HK-1 and C666-1). At least one of tumor suppressor genes could be partially demethylated after treatment with resveratrol. Four of these genes could be demethylated at different levels in NPC cell lines upon treatment of resveratrol. Moreover, we treated resveratrol to NPC cell lines and analyzed with Boyden’s chamber migration assay and wound-healing assay. We found that the cell migration abilities of resveratrol-treated TW-04, TW-076, HK-1 and C666-1 cells were decreased 37%, 78%, 62.5% and 86%, respectively. Our results implicated that resveratrol treatments reduced tumor suppressor genes’ aberrant hypermethylation levels in NPC, and might affect the regulation of cell motility in NPC. To sum up, our findings pointed out that resveratrol had potential to be developed as an anti-cancer drug and to prevent NPC metastasis.

並列關鍵字

nasopharyngeal carcinoma ； methylation ； resveratrol ； migration ； tumor suppressor gene

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