| 1. |
- Persson Skare, Tor, et al.
(författare)
-
Novel anti-VEGF therapeutics
-
Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Excessive and chronic vascular leakage in pathologies such as eye diseases leads to edema, tissue ischemia and disease progression. To suppress vascular leakage by blocking vascular endothelial growth factor (VEGF) function is clinically beneficial. However, development of new, topically applied therapeutic options is important as intravitreal injections currently carried out to deliver anti-VEGF therapeutics is expensive and may have serious side effects. VEGF receptor-2 (VEGFR2) activates Src family kinases via binding the T cell specific adaptor (TSAd) to its phosphotyrosine residue Y951. These molecular interactions are required for gap formation at endothelial junctions and vascular leakage. Here, we describe the identification from a high throughput screen, of a small molecular weight inhibitor (LC1) which blocks the interaction between the phosphorylated VEGFR2 kinase domain and TSAd. LC1 binds to TSAd in surface plasmon resonance analysis. In intact cells, LC1 suppresses VEGFR2 kinase activity while if fails to inhibit kinase activity in an in vitro biochemical kinase screen of 35 kinases including VEGFR2. Superfusion of retinal explants blocks vascular leakage from retinal vessels. In conclusion, we have identified a compound which specifically blocks VEGFR2 function in endothelial cells.
|
|
| 2. |
- Cébe-Suarez, Stéphanie, et al.
(författare)
-
Orf virus VEGF-E NZ2 promotes paracellular NRP-1/VEGFR-2 coreceptor assembly via the peptide RPPR
- 2008
-
Ingår i: The FASEB Journal. - : Wiley. - 0892-6638 .- 1530-6860. ; 22:8, s. 3078-3086
-
Tidskriftsartikel (refereegranskat)abstract
- Vascular endothelial growth factors (VEGFs) interact with the receptor tyrosine kinases (RTKs) VEGFR-1, -2, and -3; neuropilins (NRPs); and heparan sulfate (HS) proteoglycans. VEGF RTKs signal to downstream targets upon ligand-induced tyrosine phosphorylation, while NRPs and HS act as coreceptors that lack enzymatic activity yet modulate signal output by VEGF RTKs. VEGFs exist in various isoforms with distinct receptor specificity and biological activity. Here, a series of mammalian VEGF-A splice variants and orf virus VEGF-Es, as well as chimeric and mutant VEGF variants, were characterized to determine the motifs required for binding to NRP-1 in the absence (VEGF-E) or presence (VEGF-A(165)) of an HS-binding sequence. We identified the carboxyterminal peptides RPPR and DKPRR as the NRP-1 binding motifs of VEGF-E and VEGF-A, respectively. RPPR had significantly higher affinity for NRP-1 than DKPRR. VEGFs containing an RPPR motif promoted HS-independent coreceptor complex assembly between VEGFR-2 and NRP-1, independent of whether these receptors were expressed on the same or separate cells grown in cocultures. Functional studies showed that stable coreceptor assembly by VEGF correlated with its ability to promote vessel formation in an embryoid body angiogenesis assay.
|
|
| 3. |
- Kawamura, Harukiyo, et al.
(författare)
-
Neuropilin-1 in regulation of VEGF-induced activation of p38MAPK and endothelial cell organization
- 2008
-
Ingår i: Blood. - : American Society of Hematology. - 0006-4971 .- 1528-0020. ; 112:9, s. 3638-49
-
Tidskriftsartikel (refereegranskat)abstract
- Vascular endothelial growth factor (VEGF)-A regulates vascular development and angiogenesis. VEGF isoforms differ in ability to bind coreceptors heparan sulfate (HS) and neuropilin-1 (NRP1). We used VEGF-A165 (which binds HS and NRP1), VEGF-A121 (binds neither HS nor NRP1), and parapoxvirus VEGF-E-NZ2 (binds NRP1 but not HS) to investigate the role of NRP1 in organization of endothelial cells into vascular structures. All 3 ligands induced similar level of VEGFR-2 tyrosine phosphorylation in the presence of NRP1. In contrast, sprouting angiogenesis in differentiating embryonic stem cells (embryoid bodies), formation of branching pericyte-embedded vessels in subcutaneous matrigel plugs, and sprouting of intersegmental vessels in developing zebrafish were induced by VEGF-A165 and VEGF-E-NZ2 but not by VEGF-A121. Analyses of recombinant factors with NRP1-binding gain- and loss-of-function properties supported the conclusion that NRP1 is critical for VEGF-induced sprouting and branching of endothelial cells. Signal transduction antibody arrays implicated NRP1 in VEGF-induced activation of p38MAPK. Inclusion of the p38MAPK inhibitor SB203580 in VEGF-A165-containing matrigel plugs led to attenuated angiogenesis and poor association with pericytes. Our data strongly indicate that the ability of VEGF ligands to bind NRP1 influences p38MAPK activation, and formation of functional, pericyte-associated vessels.
|
|
| 4. |
- Li, Xiujuan, et al.
(författare)
-
VEGFR2 pY949 signalling regulates adherens junction integrity and metastatic spread
- 2016
-
Ingår i: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 7
-
Tidskriftsartikel (refereegranskat)abstract
- The specific role of VEGFA-induced permeability and vascular leakage in physiology and pathology has remained unclear. Here we show that VEGFA-induced vascular leakage depends on signalling initiated via the VEGFR2 phosphosite Y949, regulating dynamic c-Src and VE-cadherin phosphorylation. Abolished Y949 signalling in the mouse mutant Vegfr2(Y949F/Y949F) leads to VEGFA-resistant endothelial adherens junctions and a block in molecular extravasation. Vessels in Vegfr2(Y949F/Y949F) mice remain sensitive to inflammatory cytokines, and vascular morphology, blood pressure and flow parameters are normal. Tumour-bearing Vegfr2(Y949F/Y949F) mice display reduced vascular leakage and oedema, improved response to chemotherapy and, importantly, reduced metastatic spread. The inflammatory infiltration in the tumour micro-environment is unaffected. Blocking VEGFA-induced disassembly of endothelial junctions, thereby suppressing tumour oedema and metastatic spread, may be preferable to full vascular suppression in the treatment of certain cancer forms.
|
|
| 5. |
|
|
| 6. |
|
|
