Overexpression of the 18 kDa and 22/24 kDa FGF-2 isoforms results in differential drug resistance and amplification potential
Overexpression of the 18 kDa and 22/24 kDa FGF-2 isoforms results in differential drug resistance and amplification potential
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DOI：
10.1002/jcp.10152
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发表时间：
2002-10-01
影响因子：
5.6
通讯作者：
Del Rosso, M
中科院分区：
文献类型：
--
作者：
Dini, G;Funghini, S;Del Rosso, M
我们研究了碱性成纤维细胞生长因子 2 (FGF-2) 的低分子量 (LMW) 和高分子量 (HMW) 亚型在转化相关表型改变、药物敏感性调节和基因扩增潜力表达中的作用。为此，我们使用了转染不同 cDNA FGF-2 构建体的 NIH 3T3 和 A31 细胞，以允许表达不同的蛋白质。当表达 LMW FGF-2 或四种 HMW FGF-2 亚型时，两种细胞系均表现出明显的表型改变：它们获得了转化的形态，在 10% 血清中以更高的饱和密度生长，并表现出贴壁依赖性生长和增加的侵袭潜力。然而，表达 HMW FGF-2 的细胞也在 1% 血清中生长，其侵袭潜力低于表达所有 FGF-2 形式或单独表达 LMW FGF-2 的细胞。我们在 N-(膦乙酰基)-L-天冬氨酸 (PALA) 的选择压力下培养了不同的细胞系，PALA 是一种药物，可特异性抑制多功能氨甲酰-P-合成酶/天冬氨酸转氨甲酰酶/二氢乳清酶基因 (CAD) 的天冬氨酸转氨甲酰酶活性（从而抑制从头嘧啶生物合成），并选择具有扩增的 CAD 基因拷贝的细胞。我们的结果表明，LMW FGF-2 和/或 HMW FGF-2 亚型的异常表达通过 CAD 基因的差异扩增，不同地调节 NIH 3T3 和 A31 细胞系中的耐药性和基因扩增特性。所有亚型的共表达似乎对于获得累积效应是必要的，而核靶向 HMW FGF-2 在这种合作中发挥着关键作用。 (C) 2002 Wiley-Liss, Inc.
We investigated the role of low molecular weight (LMW) and high molecular weight (HMW) isoforms of basic fibroblast growth factor 2 (FGF-2) in the expression of transformation-related phenotypic alterations, drug sensitivity modulation, and gene amplification potential. For this purpose, we used NIH 3T3 and A31 cells transfected with different cDNA FGF-2 constructs allowing expression of the different proteins. Both cell lines showed marked phenotypic alterations when expressing the LMW FGF-2 or the four HMW FGF-2 isoforms: they acquired a transformed morphology, grew at higher saturation densities in 10% serum, and exhibited anchorage-independent growth and increased invasive potential. However, HMW FGF-2-expressing cells also grew in 1% serum and their invasive potential was lower than in cells expressing all FGF-2 forms or LMW FGF-2 alone. We have grown the different cell lines under a selective pressure of N-(phosphonacetyl)-L-aspartate (PALA), a drug which specifically inhibits the aspartate transcarbamylase activity of the multifunctional carbamyl-P-synthetase/aspartate transcarbamylase/dihydro-orotase genes (CAD) enzyme (and thus inhibits de novo pyrimidine biosynthesis) and selects for cells with amplified copies of the CAD gene. Our results demonstrate that aberrant expression of the LMW FGF-2 and/or HMW FGF-2 isoforms differently modulates drug resistance and gene amplification properties in the NIH 3T3 and A31 cell lines by differential amplification of the CAD gene. Coexpression of all isoforms appears to be necessary to obtain cumulative effects and nuclear-targeted HMW FGF-2 has a pivotal role in such a cooperation. (C) 2002 Wiley-Liss, Inc.