Inhibition of the growth of a human nasopharyngeal carcinoma cell line by bFGF is mediated via FGFR-1.
The growth of CG-1 human nasopharyngeal carcinoma cell line and five of its randomly selected, single cell-derived subline cells is inhibited by bFGF in an autocrine and paracrine manner. In contrast, aFGF, which has a 55% homology in amino acid sequence with bFGF, stimulates cell growth. Basic FGF binds to specific cell surface high-affinity receptor sites with an apparent Kd of 105 pM. Of the two lines examined, the high-affinity binding sites for bFGF are calculated to be 1200 and 2600 per cell. The biological effect of bFGF is conveyed through its binding to the high-affinity receptor sites and the binding is dependent on the presence of cell surface heparin-like molecules, as treatment of cells with heparitinase or sodium chlorate abolishes high-affinity binding and growth inhibition. In contrast, similar treatment has no obvious effect on the growth-stimulatory effect of aFGF. Experimental results are also presented showing that the growth inhibition by bFGF is mediated through type I FGF receptors. These results suggest that bFGF and aFGF act via distinct receptor types to oppositely regulate the growth of CG-1 and subline cells.
Chen
J K
JK
Department of Physiology, Chang Gung College of Medicine and Technology, Taoyuan, Taiwan.
Chao
H H
HH
Yang
V C
VC
D001483:Base Sequence; D002277:Carcinoma / Q000378:metabolism / Q000473:pathology*; D002455:Cell Division / Q000187:drug effects; D016222:Fibroblast Growth Factor 2 / Q000494:pharmacology*; D006801:Humans; D008969:Molecular Sequence Data; D009303:Nasopharyngeal Neoplasms / Q000378:metabolism / Q000473:pathology*; D016133:Polymerase Chain Reaction; D011940:Receptor Aggregation; D020794:Receptor Protein-Tyrosine Kinases; D051496:Receptor, Fibroblast Growth Factor, Type 1; D017468:Receptors, Fibroblast Growth Factor / Q000378:metabolism*; D014407:Tumor Cells, Cultured
D017468:Receptors, Fibroblast Growth Factor; D016222:Fibroblast Growth Factor 2; C496348:FGFR1 protein, human; D020794:Receptor Protein-Tyrosine Kinases; D051496:Receptor, Fibroblast Growth Factor, Type 1