Transformation of NIH/3T3 cells by ornithine decarboxylase overexpression.
Transformation of NIH/3T3 cells by ornithine decarboxylase overexpression.
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DOI：
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发表时间：
1993-06
期刊：
影响因子：
11.2
通讯作者：
J. Moshier;J. Dosescu;M. Skunca;G. Luk
中科院分区：
文献类型：
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作者：
J. Moshier;J. Dosescu;M. Skunca;G. Luk
鸟氨酸脱羧酶(ODC)在多胺生物合成中起着限速作用，与细胞的增殖和功能密切相关。尽管在转化的细胞和肿瘤中持续检测到高水平的ODC mRNA、蛋白和酶活性，但问题仍然是ODC基因的过度表达是否在肿瘤发生中起到致病作用。我们已经在人β-肌动蛋白启动子的转录控制下，用含有人ODC互补DNA的表达载体稳定地转染了NIH/3T3成纤维细胞。对转染β-肌动蛋白/ODC DNA的细胞(NODC细胞)和对照细胞(NLK细胞)进行ODC基因表达和细胞生长特性的分析。与NLK细胞相比，NODC细胞的ODC活性和mRNA水平升高了3-6倍。与NLK对照细胞相比，NODC细胞不受接触抑制，表现出贴壁无关的生长，周期更快，在裸鼠体内更有效和更快地诱发肿瘤。这些结果直接为ODC基因表达的错误调控在获得转化表型中的作用建立了原因，并为研究ODC和其他基因产物在肿瘤发展中的相互作用提供了一个模型。
Ornithine decarboxylase (ODC) plays a rate-limiting role in polyamine biosynthesis and is intimately associated with cell proliferation and function. Although elevated levels of ODC mRNA, protein, and enzyme activity are consistently detected in transformed cells and tumors, the question remains as to whether ODC gene overexpression has a causative role in tumorigenesis. We have stably transfected NIH/3T3 fibroblasts with an expression construct containing human ODC complementary DNA under transcriptional control of the human beta-actin promoter. Cells transfected with the beta-actin/ODC DNA construct, designated NODC cells, and control transfectants, termed NLK cells, were analyzed for ODC gene expression and cell growth characteristics. ODC activity and mRNA levels were elevated 3-6-fold in NODC cells relative to NLK cells. NODC cells, in contrast to NLK control cells, are not contact inhibited, exhibit anchorage-independent growth, cycle more rapidly, and induce tumors in nude mice more efficiently and rapidly. These results directly establish a causative role for the misregulation of ODC gene expression in the acquisition of a transformation phenotype and provide a model to examine the interaction of ODC and other gene products in neoplastic development.