Vallés A M, Tucker G C, Thiery J P, Boyer B
Laboratoire de Physiopathologie du Développement, Centre National de la Recherche Scientifique, URA 1337, Paris, France.
Cell Regul. 1990 Dec;1(13):975-88. doi: 10.1091/mbc.1.13.975.
The dual function exerted by acidic fibroblast growth factor (aFGF) in a rat bladder carcinoma cell line has been explored under two different conditions of culture density. At low cell density, aFGF promotes the epithelium-to-mesenchyme transition of NBT-II cells characterized by cell dissociation, morphological changes toward a fibroblastic-like phenotype, and acquisition of cell motility. Under these conditions, NBT-II cells are unresponsive to the growth-promoting effect of aFGF. At high cell density, aFGF is a potent mitogenic factor, but its scattering activity is essentially abrogated. Slight modifications in the binding of aFGF to its specific receptors were observed at high cell density; these changes correlated with a downregulation of receptors with no apparent change in their molecular form. NBT-II cells located at the edge of artificial wounds mimicked the behavior of subconfluent cells, because they did not proliferate upon aFGF treatment. Furthermore, in large-sized NBT-II colonies, peripheral cells were the first to dissociate in response to aFGF. Altogether, our results suggest that the cellular response to multifunctional growth factors might depend on the localization within the responding cell population.
在两种不同的培养密度条件下，对酸性成纤维细胞生长因子（aFGF）在大鼠膀胱癌细胞系中发挥的双重功能进行了探索。在低细胞密度下，aFGF促进NBT-II细胞的上皮-间质转化，其特征为细胞解离、形态向成纤维细胞样表型转变以及获得细胞运动性。在这些条件下，NBT-II细胞对aFGF的促生长作用无反应。在高细胞密度下，aFGF是一种有效的促有丝分裂因子，但其散射活性基本被消除。在高细胞密度下观察到aFGF与其特异性受体结合的轻微变化；这些变化与受体的下调相关，而其分子形式无明显变化。位于人工伤口边缘的NBT-II细胞模仿了亚汇合细胞的行为，因为它们在aFGF处理后不增殖。此外，在大型NBT-II集落中，周边细胞是最先响应aFGF而解离的。总之，我们的结果表明，细胞对多功能生长因子的反应可能取决于反应细胞群体中的定位。
