LRP-1/TbetaR-V mediates TGF-beta1-induced growth inhibition in CHO cells.

The type V transforming growth factor-beta (TGF-beta) receptor (TbetaR-V) is hypothesized to be involved in cellular growth inhibition by TGF-beta(1). Recently, TbetaR-V was found to be identical to low density lipoprotein receptor-related protein-1 (LRP-1). Here we demonstrate that TGF-beta(1) inhibits growth of wild-type CHO cells but not LRP-1-deficient mutant cells (CHO-LRP-1(-) cells). Stable transfection of CHO-LRP-1(-) cells with LRP-1 cDNA restores the wild-type morphology and the sensitivity to growth inhibition by TGF-beta(1). In addition, overexpression of LRP-1 minireceptors exerts a dominant negative effect and attenuates the growth inhibitory response to TGF-beta(1) in wild-type CHO cells. These results suggest that LRP-1/TbetaR-V is critical for TGF-beta(1)-mediated growth inhibition in CHO cells.