[Transforming growth factor beta and fibroblast growth factor have opposite effects on the proliferation of endothelial cells]

Abstract

Recent data indicate that beta type transforming growth factor (TGF-beta) may be a bifunctional regulator of cellular growth: it induces anchorage-independent growth of certain cells but is also capable of inhibiting anchorage-dependent or -independent proliferation of a variety of normal epithelial and transformed cells. We show that TGF-beta is also a reversible inhibitor of proliferation of bovine aortic endothelial cells in culture. TGF-beta inhibits the proliferation of endothelial cells grown in the presence of basic fibroblast growth factor (bFGF). Dose-dependent inhibition occurs at 0.2-2.0 ng/ml TGF-beta. Inhibition of cell proliferation in the presence of a maximally stimulating dose of bFGF is not overcome by a tenfold excess of bFGF, suggesting that antagonism of bFGF-induced cell proliferation by TGF-beta is of a non-competitive nature. TGF-beta affects the morphology of confluent cells in a reversible manner.