細胞核中的 CTEN 於腫瘤發生過程中所扮演的角色

The Role of Nuclear CTEN in Tumorigenesis

黃彥康(Yen-kang Huang)

指導教授 ： 廖憶純

國立臺灣大學/生命科學院/生化科技學系/碩士(2015年)

https://doi.org/10.6342/NTU.2015.10592

摘要

摘要
C-terminal tensin-like (CTEN) 為位於 focal adhesion 上tensin 家族的一員，除了前列腺和胎盤組織外，在其他正常組織中表現不多，但是在許多的癌症，如肺癌、大腸癌以及乳癌中卻有表現量上升的情況，除了 focal adhesion，CTEN在大腸癌細胞株 SW480 與 HCT 116 中有在核內累積的現象。在細胞核中大量存在的 CTEN 也被證實會和 Wnt pathway 中的 beta-catenin 結合並促進腫瘤發生。另一方面，若在正常的人類腎臟胚胎細胞 293A 與正常的前列腺細胞 RWPE-1 表現 CTEN，則會在細胞質內分布較多，顯示 CTEN 在細胞內的位置與細胞癌化的高度相關性。本論文假設 CTEN 在核內的累積會促使細胞癌化。藉由在 CTEN 蛋白質上加上 nucleus localization signal (NLS) 或 Src myristoylation signal，改變 CTEN 在細胞內的分布，並了解 CTEN 分布的差異對細胞癌化特性的影響。首先建立穩定表現帶有特殊胺基酸訊號 (NLS signal and Src myristoylation signal) 的 CTEN 蛋白質之細胞株，以西方墨點法 (western blot) 與免疫螢光法 (immunofluorescence) 確認在細胞內表現含不同訊號的CTEN 時，確實會導致 CTEN 在細胞內的分布有相對應的改變。接著以 cell proliferation assay 初步觀察不同 CTEN 分佈對細胞生理的影響，發現 CTEN 於細胞核內累積並不影響細胞生長速率。

關鍵字

腫瘤發生 ； 與細胞膜結合 ； 進核 ； 癌症 ； 蛋白質分佈 ； 細胞生長速率

並列摘要

C-terminal tensin-like (CTEN) locates in focal adhesion and belongs to tensin family. CTEN expresses much in prostate and placenta, but rarely expresses in other normal tissues. Elevated CTEN level has been detected in lung cancer, colorectal cancer and breast cancer. In addition to focal adhesion, CTEN also accumulates in the nucleus in colorectal cancer cell lines SW480 and HCT 116. It has been found that CTEN in nucleus interacts with Wnt pathway signal beta-catenin and promotes tumorigenesis. On the other hand, human kidney embryonic cell 293A and normal prostate cell RWPE-1 express CTEN predominantly in cytoplasm. It is shown that CTEN localization is related to tumorigenesis. We assumpted that CTEN accumulation in the nucleus will lead to tumor. By adding special signaling amino acid sequence, nucleus localization signal (NLS) and Src myristoylation signal cause CTEN to change localization in cell. Therefore, we can observe tumorigenesis of cells with different CTEN localization. First, we established stable cell lines expressing CTEN protein with special amino acid signals. We checked with western blot and immunofluorescence, and we confirmed that expressing CTEN with different signals does cause CTEN distribution changes. Then, we used cell proliferation assay to observe the effect of CTEN distribution in tumorigenesis, and we found that CTEN accumulation in cell nucleus do not affect cell proliferation rate.

並列關鍵字

Tumorigenesis ； CTEN ； tensin ； distribution ； localization ； cancer ； tumor ； membrane-targeting ； nucleus-targeting ； cell proliferation rate

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