TIMP-2 disrupts FGF-2-induced downstream signaling pathways.
We have previously reported that tissue inhibitor of metalloproteinases-2 (TIMP-2), an endogenous inhibitor of matrix metalloproteinase, modulates angiogenic responses through the MMP inhibition-independent activity. In this study, we investigate the molecular mechanisms of TIMP-2-mediated growth inhibition in response to fibroblast growth factor-2 (FGF-2). Pre-treatment with a protein tyrosine phosphatase inhibitor orthovanadate or expression of a dominant negative Shp-1 mutant fails to induce TIMP-2 inactivation of FGF-2 signaling pathways in human microvascular endothelial cells. We also show that TIMP-2 inhibition of FGF-2-induced p42/44(MAPK) activation and cell proliferation is associated with TIMP-2 binding to integrin alpha3beta1 on endothelial cell surfaces, as demonstrated by use of anti-integrin alpha3 or beta1 blocking antibodies, or disruption of integrin alpha3 expression by siRNA. Collectively, our results indicate that TIMP-2 inhibits FGF-2 signaling pathways through association with integrin alpha3beta1 and Shp-1-dependent inhibition of p42/44(MAPK) signaling, which in turn, results in suppression of FGF-2-stimulated endothelial cell mitogenesis.
Seo
Dong-Wan
DW
Department of Molecular Bioscience, Institute of Bioscience and Biotechnology, School of Bioscience and Biotechnology, Kangwon National University, Chuncheon 200-701, Republic of Korea. dwseomb@kangwon.ac.kr
Kim
Soo Hyeon
SH
Eom
Seok-Hyun
SH
Yoon
Hyun Jae
HJ
Cho
Young-Rak
YR
Kim
Pyeung-Hyeun
PH
Kim
Yong Kee
YK
Han
Jeung-Whan
JW
Diaz
Tere
T
Wei
Bei-Yang
BY
Stetler-Stevenson
William G
WG
D001483:Base Sequence; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D042783:Endothelial Cells / Q000166:cytology / Q000187:drug effects* / Q000502:physiology; D016222:Fibroblast Growth Factor 2 / Q000494:pharmacology* / Q000502:physiology; D006801:Humans; D039201:Integrin alpha3beta1 / Q000037:antagonists & inhibitors / Q000235:genetics / Q000502:physiology; D020935:MAP Kinase Signaling System / Q000187:drug effects / Q000502:physiology; D020782:Matrix Metalloproteinases / Q000502:physiology; D019950:Mitogen-Activated Protein Kinase 1 / Q000037:antagonists & inhibitors / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3 / Q000037:antagonists & inhibitors / Q000378:metabolism; D018919:Neovascularization, Physiologic; D053824:Protein Tyrosine Phosphatase, Non-Receptor Type 6 / Q000502:physiology; D034741:RNA, Small Interfering / Q000235:genetics; D051496:Receptor, Fibroblast Growth Factor, Type 1 / Q000502:physiology; D011994:Recombinant Proteins / Q000494:pharmacology; D015398:Signal Transduction / Q000187:drug effects* / Q000502:physiology; D019716:Tissue Inhibitor of Metalloproteinase-2 / Q000494:pharmacology* / Q000502:physiology
D039201:Integrin alpha3beta1; D034741:RNA, Small Interfering; D011994:Recombinant Proteins; D016222:Fibroblast Growth Factor 2; D019716:Tissue Inhibitor of Metalloproteinase-2; C496348:FGFR1 protein, human; D051496:Receptor, Fibroblast Growth Factor, Type 1; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; C509249:PTPN6 protein, human; D053824:Protein Tyrosine Phosphatase, Non-Receptor Type 6; D020782:Matrix Metalloproteinases