乳癌細胞MCF-7感染反義第一型胰島素生長因子（IGF-I）基因生長速率降低機制的探討

Transfection of Antisense Human Insulin-Like Growth Factor-I (IGF-I) Complementary DNA Reduces Proliferation Rate of MCF-7 Breast Carcinoma Cells

鐘于芳(Yu-Fang Chung) ； 黃秋琴(Chiu-Chin Hwang) ； 譚懿文(Yi-Wen Tan) ； 方剛(Kang Fang)

《師大生物學報》 33卷1期 (1998/06) Pp. 23-35

https://doi.org/10.29812/BBNTNU.199806.0003

摘要

本文以人類乳癌細胞株MCF-7為材料，萃取RNA後，進行反轉錄聚合酵素連鎖反應所得完整第一型類胰島素生長因子（IGF-I）cDNA，經純化後，再銜接至pGem-T載質體，經篩選得純系複製後，將IGF-I基因從質體中切出，與含強烈啟動子（promoter）載體構築成反義（anti-sense）IGF-I質體，再感染（transfect）至人類乳癌細胞株MCF-7，利用此載體所含啟動子，表現反義IGF-I基因，使正常（wild-type）的IGF-I RNA表現抑制。實驗結果顯示，經反義IGF-I基因質體感染後細胞株較僅為載體感染後細胞株之生長速率降低。而由反轉錄聚合酵素連鎖反應檢測，顯示反義基因感染後，細胞IGF-I RNA的表現會降低，此外也發現原所有轉形生長因子（TGF-α）自泌刺激效應也一併降低。此一結果對癌細胞研究生長因子重要性與相關性是一個很有用的模式。

關鍵字

第一型類胰島素生長因子 ； 反義基因 ； 人類乳癌細胞

並列摘要

The proliferation of human breast cancer cell s is regulated by IGF-I-stimulated autocrine loop. The present study was designed by transfecting breast cancer line, MCF-7, with construct of human IGF-I cDNA in antisense orientation and its expression controlled by a strong eukaryotic promoter. The expressed antisense IGF-I transcript is to neutralize endogenous IGF-l translation. The growth rate of the cloned cells MCF-7 with antisense construct that can be selected for G418 resistance were shown reduced in cell growth rate compared to cells that were transfected with vector alone and the parental cells. In addition, IGF-I transcript level was observed reduced in the cells with anti sense IGF-I construct. In addition, the cells with antisense TGF-α contruct was shown with down-regulated TGF-α expression. The result of this work pro vides a good model for studying the effects of reduction in endogenous IGF-α expression on anchorage-dependent cell growth in vitro.

並列關鍵字

Insulin-like growth factor-I ； Antisense ； Breast cancer cells