Highly invasive melanoma cells activate the vascular endothelium via an MMP-2/integrin αvβ5-induced secretion of VEGF-A.
Tumor cell extravasation is a critical step in the metastatic cascade and requires interaction between the tumor cell and the endothelium. Although cancer progression depends on a complex network of mechanisms, including inflammation and coagulation, the involvement of tumor-induced endothelium activation and the subsequent release of procoagulatory factors in this process are not well understood. Using tissue sections from patients with malignant melanoma, immunofluorescence studies for the presence of von Willebrand factor (VWF) clearly demonstrated endothelium activation and the formation of ultra-large VWF fibers in these patients. In vitro analyses revealed that supernatants from highly invasive melanoma cells induced an acute endothelium activation measured by VWF, P-selectin, and angiopoietin-2 release. Proteome profiling identified vascular endothelial growth factor A (VEGF-A) as the main mediator of endothelium activation. Inhibition and knock-down of VEGF-A in melanoma cells led to a rigorous decrease in VWF exocytosis. Selective small-interfering RNA to matrix metalloproteinase-2 (MMP-2) inhibited endothelium activation, and this effect correlated with reduced VEGF-A content in the supernatants of melanoma cells. Further experiments showed that active MMP-2 regulates VEGF-A in melanoma cells on a transcriptional level via an integrin αvβ5/phosphoinositide-3-kinase-dependent pathway. In conclusion, these results indicate an important role of VEGF-A in acute endothelium activation and provide clear evidence that MMP-2 plays a pivotal role in the autocrine regulation of VEGF-A expression in melanoma cells.
Division of Experimental Dermatology, Department of Dermatology, Venereology, and Allergology, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany. anna.desch@medma.uni-heidelberg.de
Anna
A
Desch
Elwira A
EA
Strozyk
Alexander T
AT
Bauer
Volker
V
Huck
Verena
V
Niemeyer
Thomas
T
Wieland
Stefan W
SW
Schneider
D000328:Adult; D000818:Animals; D045744:Cell Line, Tumor; D002462:Cell Membrane / Q000378:metabolism; D004730:Endothelium, Vascular / Q000201:enzymology* / Q000473:pathology*; D004789:Enzyme Activation; D015972:Gene Expression Regulation, Neoplastic; D055785:Gene Knockdown Techniques; D006801:Humans; D008297:Male; D053511:Matrix Metalloproteinase 14 / Q000378:metabolism; D020778:Matrix Metalloproteinase 2 / Q000378:metabolism*; D008545:Melanoma / Q000098:blood supply / Q000201:enzymology* / Q000235:genetics / Q000473:pathology*; D051379:Mice; D008954:Models, Biological; D009361:Neoplasm Invasiveness; D009389:Neovascularization, Pathologic / Q000235:genetics / Q000473:pathology; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D019030:Receptors, Vitronectin / Q000378:metabolism*; D015398:Signal Transduction; D012878:Skin Neoplasms / Q000098:blood supply / Q000201:enzymology / Q000235:genetics / Q000473:pathology; D042461:Vascular Endothelial Growth Factor A / Q000235:genetics / Q000378:metabolism*; D040301:Vascular Endothelial Growth Factor Receptor-2 / Q000378:metabolism; D014841:von Willebrand Factor / Q000378:metabolism
D012333:RNA, Messenger; D019030:Receptors, Vitronectin; C467484:VEGFA protein, human; D042461:Vascular Endothelial Growth Factor A; C064660:integrin alphaVbeta5; D014841:von Willebrand Factor; D019869:Phosphatidylinositol 3-Kinases; D040301:Vascular Endothelial Growth Factor Receptor-2; C522361:MMP2 protein, human; D020778:Matrix Metalloproteinase 2; D053511:Matrix Metalloproteinase 14