TY - JOUR T1 - Vascular endothelial growth factor B (VEGF-B) binds to VEGF receptor-1 and regulates plasminogen activator activity in endothelial cells JF - Proc Natl Acad Sci U S A Y1 - 1998 A1 - Olofsson, B A1 - Korpelainen, E A1 - Pepper, M S A1 - Mandriota, S J A1 - Aase, K A1 - Kumar, V A1 - Gunji, Y A1 - Jeltsch, M M A1 - Shibuya, M A1 - Alitalo, K A1 - Eriksson, U AB - The vascular endothelial growth factor (VEGF) family has recently expanded by the identification and cloning of three additional members, namely VEGF-B, VEGF-C, and VEGF-D. In this study we demonstrate that VEGF-B binds selectively to VEGF receptor-1/Flt-1. This binding can be blocked by excess VEGF, indicating that the interaction sites on the receptor are at least partially overlapping. Mutating the putative VEGF receptor-1/Flt-1 binding determinants Asp63, Asp64, and Glu67 to alanine residues in VEGF-B reduced the affinity to VEGF receptor-1 but did not abolish binding. Mutational analysis of conserved cysteines contributing to VEGF-B dimer formation suggest a structural conservation with VEGF and platelet-derived growth factor. Proteolytic processing of the 60-kDa VEGF-B186 dimer results in a 34-kDa dimer containing the receptor-binding epitopes. The binding of VEGF-B to its receptor on endothelial cells leads to increased expression and activity of urokinase type plasminogen activator and plasminogen activator inhibitor 1, suggesting a role for VEGF-B in the regulation of extracellular matrix degradation, cell adhesion, and migration. VL - 95 UR - http://view.ncbi.nlm.nih.gov/pubmed/9751730 IS - 20 JO - Proceedings of the National Academy of Sciences of the United States of America ER - TY - JOUR T1 - Vascular endothelial growth factor (VEGF)-C synergizes with basic fibroblast growth factor and VEGF in the induction of angiogenesis in vitro and alters endothelial cell extracellular proteolytic activity JF - J Cell Physiol Y1 - 1998 A1 - Pepper, M S A1 - Mandriota, S J A1 - Jeltsch, M A1 - Kumar, V A1 - Alitalo, K AB - Vascular endothelial growth factor-C (VEGF-C) is a recently characterized member of the VEGF family of angiogenic polypeptides. We demonstrate here that VEGF-C is angiogenic in vitro when added to bovine aortic or lymphatic endothelial (BAE and BLE) cells but has little or no effect on bovine microvascular endothelial (BME) cells. As reported previously for VEGF, VEGF-C and basic fibroblast growth factor (bFGF) induced a synergistic in vitro angiogenic response in all three cells lines. Unexpectedly, VEGF and VEGF-C also synergized in the in vitro angiogenic response when assessed on BAE cells. Characterization of VEGF receptor (VEGFR) expression revealed that BME, BAE, and BLE cell lines express VEGFR-1 and -2, whereas of the three cell lines assessed, only BAE cells express VEGFR-3. We also demonstrate that VEGF-C increases plasminogen activator (PA) activity in the three bovine endothelial cell lines and that this is accompanied by a concomitant increase in PA inhibitor-1. Addition of alpha2-antiplasmin to BME cells co-treated with bFGF and VEGF-C partially inhibited collagen gel invasion. These results demonstrate, first, that by acting in concert with bFGF or VEGF, VEGF-C has a potent synergistic effect on the induction of angiogenesis in vitro and, second, that like VEGF and bFGF, VEGF-C is capable of altering endothelial cell extracellular proteolytic activity. These observations also highlight the notion of context, i.e., that the activity of an angiogenesis-regulating cytokine depends on the presence and concentration of other cytokines in the pericellular environment of the responding endothelial cell. VL - 177 UR - http://view.ncbi.nlm.nih.gov/pubmed/9808152 IS - 3 JO - Journal of Cellular Physiology ER - TY - JOUR T1 - Proteolytic processing regulates receptor specificity and activity of VEGF-C JF - EMBO J Y1 - 1997 A1 - Joukov, V A1 - Sorsa, T A1 - Kumar, V A1 - Jeltsch, M A1 - Claesson-Welsh, L A1 - Cao, Y A1 - Saksela, O A1 - Kalkkinen, N A1 - Alitalo, K AB - The recently identified vascular endothelial growth factor C (VEGF-C) belongs to the platelet-derived growth factor (PDGF)/VEGF family of growth factors and is a ligand for the endothelial-specific receptor tyrosine kinases VEGFR-3 and VEGFR-2. The VEGF homology domain spans only about one-third of the cysteine-rich VEGF-C precursor. Here we have analysed the role of post-translational processing in VEGF-C secretion and function, as well as the structure of the mature VEGF-C. The stepwise proteolytic processing of VEGF-C generated several VEGF-C forms with increased activity towards VEGFR-3, but only the fully processed VEGF-C could activate VEGFR-2. Recombinant 'mature' VEGF-C made in yeast bound VEGFR-3 (K[D] = 135 pM) and VEGFR-2 (K[D] = 410 pM) and activated these receptors. Like VEGF, mature VEGF-C increased vascular permeability, as well as the migration and proliferation of endothelial cells. Unlike other members of the PDGF/VEGF family, mature VEGF-C formed mostly non-covalent homodimers. These data implicate proteolytic processing as a regulator of VEGF-C activity, and reveal novel structure-function relationships in the PDGF/VEGF family. VL - 16 UR - http://view.ncbi.nlm.nih.gov/pubmed/9233800 IS - 13 JO - The EMBO Journal ER - TY - JOUR T1 - Vascular endothelial growth factors VEGF-B and VEGF-C JF - J Cell Physiol Y1 - 1997 A1 - Joukov, V A1 - Kaipainen, A A1 - Jeltsch, M A1 - Pajusola, K A1 - Olofsson, B A1 - Kumar, V A1 - Eriksson, U A1 - Alitalo, K VL - 173 UR - http://view.ncbi.nlm.nih.gov/pubmed/9365524 IS - 2 JO - Journal of Cellular Physiology ER -