| Title: |
Integrin-mediated action of insulin-like growth factor binding protein-2 in tumor cells |
| Authors: |
Schutt, BS; Langkamp, M; Rauschnabel, U; Ranke, MB; Elmlinger, MW |
| Source: |
Journal of Molecular Endocrinology ; volume 32, issue 3, page 859-868 ; ISSN 0952-5041 1479-6813 |
| Publisher Information: |
Bioscientifica |
| Publication Year: |
2004 |
| Description: |
The neoplastic production of the insulin-like growth factor binding protein (IGFBP)-2 often correlates with tumor malignancy and aggressiveness. Since IGFBP-2 contains an RGD motif in its C-terminus, it was hypothesized that this protein may act independently of IGF on tumor cells through integrins. To investigate this, integrin binding, intracellular signaling and the impact of IGFBP-2 on cell adhesion and proliferation were examined in two tumor cell lines. In tracer displacement studies, up to 30% of the added (125)I-hIGFBP-2 specifically bound to the cells. Bound (125)I-hIGFBP-2 was reversibly displaced by IGFBP-2, IGFBP-1 and RGD-(Gly-Arg-Asp)-containing peptides, but not by IGFBP-3, -4, -5, -6 and RGE-(Gly-Arg-Glu)-containing peptides. Blocking with antibodies directed against different integrins and with fibronectin demonstrated that IGFBP-2 cell surface binding is specific for alpha5beta1-integrin. Incubation of IGFBP-2 with equimolar quantities of IGF-I and IGF-II annihilated RGD-specific binding. IGFBP-2 binding at the cell surface led to dephosphorylation of the focal adhesion-kinase (FAK) of up to 37% (P |
| Document Type: |
article in journal/newspaper |
| Language: |
unknown |
| DOI: |
10.1677/jme.0.0320859 |
| Availability: |
https://doi.org/10.1677/jme.0.0320859; https://jme.bioscientifica.com/view/journals/jme/32/3/859.xml; https://jme.bioscientifica.com/downloadpdf/journals/jme/32/3/859.xml |
| Accession Number: |
edsbas.69464EEF |
| Database: |
BASE |