The insulin-like growth factor II (IGF-II)/mannose 6-phosphate receptor mediates IGF-II-induced motility in human rhabdomyosarcoma cells. |
| |
| Authors: | C P Minniti E C Kohn J H Grubb W S Sly Y Oh H L Müller R G Rosenfeld L J Helman |
| |
| Institution: | Molecular Genetics Section, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892. |
| |
| Abstract: | Insulin-like growth factor-II (IGF-II) is an autocrine growth and motility factor for human rhabdomyosarcoma. It interacts with three different receptors: the IGF-I, the IGF-II, and the insulin receptor. A specific function of the IGF-II receptor in mediating IGF-II responses has not been defined. In this report we investigate the mechanism of IGF-II-mediated motility in rhabdomyosarcoma cells. We demonstrate that IGF-II and Leu27]IGF-II, an analog selective for the IGF-II receptor, stimulate motility at concentrations in which they interact only with their own receptor. An antibody that blocks the IGF-I receptor does not inhibit either peptide activity, while an antibody specific for the IGF-II receptor suppresses the IGF-II-induced motility. This antibody does not interfere with rhabdomyosarcoma cell proliferation. We conclude that in rhabdomyosarcoma cells IGF-II stimulates two different responses mediated by distinct receptors: 1) a mitogenic response through the type I receptor and 2) a motility response through the type II receptor. |
| |
| Keywords: | |
|
|
