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- Huang, Hua, et al.
(author)
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VEGF suppresses T-lymphocyte infiltration in the tumor microenvironment through inhibition of NF-κB-induced endothelial activation
- 2015
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In: The FASEB Journal. - : Wiley. - 0892-6638 .- 1530-6860. ; 29:1, s. 227-238
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Journal article (peer-reviewed)abstract
- Antiangiogenic treatment targeting the vascular endothelial growth factor (VEGF) signaling pathway is in clinical use, but its effect on vascular function and the tumor microenvironment is poorly understood. Here, we investigate cross-talk between VEGF and proinflammatory TNF-α signaling in endothelial cells and its impact on leukocyte recruitment. We found that cotreatment with VEGF decreased TNF-α-induced Jurkat cell adhesion to human microvascular endothelial cells by 40%. This was associated with inhibition of TNF-α-mediated regulation of 86 genes, including 2 T-lymphocyte-attracting chemokines, CXCL10 and CXCL11 [TNF-α concentration 1 ng/ml; 50% inhibition/inhibitory concentration (IC50) VEGF, 3 ng/ml]. Notably, VEGF directly suppressed TNF-α-induced gene expression through negative cross-talk with the NF-κB-signaling pathway, leading to an early decrease in IFN regulatory factor 1 (IRF-1) expression and reduced phosphorylation of signal transducer and activator of transcription 1 (p-Stat1) at later times. Inhibition of VEGF signaling in B16 melanoma tumor-bearing mice by sunitinib treatment resulted in up-regulation of CXCL10 and CXCL11 in tumor vessels, accompanied by up to 18-fold increased infiltration of CD3(+) T-lymphocytes in B16 tumors. Our results demonstrate a novel role of VEGF in negative regulation of NF-κB signaling and endothelial activation in the tumor microenvironment and provide evidence that pharmacological inhibition of VEGF signaling enhances T-lymphocyte recruitment through up-regulation of chemokines CXCL10 and CXCL11.-Huang, H., Langenkamp, E., Georganaki, M., Loskog, A., Fuchs, P. F., Dieterich, L. C., Kreuger, J., Dimberg, A. VEGF suppresses T-lymphocyte infiltration in the tumor microenvironment through inhibition of NF-κB-induced endothelial activation.
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| 2. |
- Langenkamp, Elise, et al.
(author)
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Elevated Expression of the C-Type Lectin CD93 in the Glioblastoma Vasculature Regulates Cytoskeletal Rearrangements That Enhance Vessel Function and Reduce Host Survival
- 2015
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In: Cancer Research. - 0008-5472 .- 1538-7445. ; 75:21, s. 4504-4516
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Journal article (peer-reviewed)abstract
- Glioblastoma is an aggressive brain tumor characterized by an abnormal blood vasculature that is hyperpermeable. Here, we report a novel role for CD93 in regulating angiogenesis in this setting by modulating cell-cell and cell-matrix adhesion of endothelial cells. Tissue microarray analysis demonstrated that vascular expression of CD93 was correlated with poor survival in a clinical cohort of patients with high-grade astrocytic glioma. Similarly, intracranial growth in the GL261 mouse model of glioma was delayed significantly in CD93(-/-) hosts, resulting in improved survival compared with wild-type mice. This effect was associated with increased vascular permeability and decreased vascular perfusion of tumors, indicating reduced vessel functionality in the absence of CD93. RNAi-mediated attenuation of CD93 in endothelial cells diminished VEGF-induced tube formation in a three-dimensional collagen gel. CD93 was required for efficient endothelial cell migration and proper cell polarization in vitro. Further, in endothelial cells where CD93 was attenuated, decreased cell spreading led to a severe reduction in cell adhesion, a lack of proper cell contacts, a loss of VE-cadherin, and aberrant actin stress fiber formation. Our results identify CD93 as a key regulator of glioma angiogenesis and vascular function, acting via cytoskeletal rearrangements required for cell-cell and cell-matrix adhesion.
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