論文名稱:

APE1/Ref-1影響細胞防禦氧化壓力功能之研究

 

Effects of APE1/Ref-1 on Cellular Resistance to Oxidative Stress

研究生:

黃建程  Chien-Cheng Huang

 

(以作者名查詢陽明大學館藏系統)

 

(以作者名查詢全國圖書書目資訊網)

指導教授:

夏堪臺  Kan-Tai Hsia

        學位類別:

碩士

        學校名稱:

國立陽明大學

系所名稱:

口腔生物研究所

            學號:

39317009

          學年度:

94

          語文別:

中文

          出版年:

95

關鍵字:

口腔癌  oral cancer

 

  APE1

 

  Ref-1

全文說明:

(本論文未授權公開)

 

電子全文

        論文頁數:

83

摘要:

鹼基刪除修復[ base excision repair (BER) pathway ]是細胞受到烷化物(alkylation agent)及氧化性傷害的主要修復機制,當BER pathway啟動時,其中參與BER的蛋白質—apurinic/apyrimidinic 1endonuclease/redox factor-1 (APE1/Ref-1 )會辨識DNA上的AP-site,並且在AP-site5’端進行切割,之後再由其他BER蛋白質去繼續進行DNA修復。此外,APE1/Ref-1也是一個reduction-oxidation (redox) factor,可幫助轉錄因子維持活化的還原形式,並能提高轉錄因子結合到DNA的能力,進而去引發細胞產生不同的反應,諸如:細胞生長、分化及細胞凋亡。過去的研究指出,在子宮頸癌,卵巢癌、前列腺癌,均發現APE1/Ref-1有高度的表現量,且其在細胞核質的比例亦有異常改變,是以推論APE1/Ref-1和口腔癌之間亦有一定的相關性,而檳榔、香菸為已知之致癌物質其可能會造成ROS的產生而可能進一步的使細胞內DNA產生變異。因此,本研究欲探討可造成口腔癌化的物質檳榔子萃取物以及尼古丁對於APE1/Ref-1之影響為何。

 

本研究以H2O2、檳榔子萃取物(areca nut extract, ANE) 以及尼古丁(nicotine)刺激HaCaT以及SAS細胞後,發現APE1/Ref-1的蛋白表現量會有上升的情形。本研究並建構了可大量表現APE1/Ref-1之細胞株,並以檳榔子萃取物(areca nut extract, ANE)刺激後,發現可大量表現APE1/Ref-1之細胞株對於檳榔子萃取物(areca nut extract, ANE)具有較好的抵抗性,並且受到檳榔子萃取物(areca nut extract, ANE)刺激後所產生的ROS亦較少,另外大量表現APE1/Ref-1亦會影響細胞週期的改變。

 

綜觀本研究之結果,受到口腔致癌物的刺激後,APE1/Ref-1表現會增多,其可能會改變其修復或是氧化還原的功能,而影響細胞,另外,大量表現APE1/Ref-1似乎具有保護細胞的作用,因此推測APE1/Ref-1的表現可能影響細胞對刺激物質之抗性。

   
 

The DNA base excision repair (BER) pathway is responsible for the cellular and oxidative DNA damage. In the BER pathway, apurinic/apyrimidinic endonuclease/redox effector factor (APE1/Ref-1) acts as an 5’-endonuclease, and it can remove apurinic/apyrimidinic (AP) site. APE1/Ref-1 is a multifunctional protein that is not only responsible for repair of AP sites, but also functions as a reduction-oxidation (redox) factor maintaining transcription factors in an active reduced state. It has been shown to stimulate the DNA binding activity of numerous transcription factors that are involved in cell proliferation, differentiation and so on. APE1/Ref-1 levels have been found to be elevated in a number of cancers such as cervical cancer, ovarian cancer and prostate cancer. Also, the cellular locations of APE1/Ref-1 in many cancers distribute abnormally.

 

In this study, H2O2, ANE and nicotine were as oxidative stimuli to observe the expression of APE1/Ref-1 in oral cancer cell lines. APE1/Ref-1 expression was elevated after H2O2, ANE and nicotine treatments in western blot. Furthermore, overexpression of APE1/Ref-1 may protect cell form ANE toxicity. It seems that overexpression of APE1/Ref-1 may suppress the ROS production after treatment of ANE and influence the cell cycle.

 

In conclusion, the APE1/Ref-1 was elevated after H2O2, ANE and nicotine treatments and overexpression of APE1/Ref-1 may protect cell form ANE toxicity. It can suggest that expression of APE1/Ref-1 may be related to the resistance of oral cancer.