Endothelin axis induces metalloproteinase activation and invasiveness in human lymphatic endothelial cells.
The molecular mechanisms involved in lymphangiogenesis were unknown until recently. We previously demonstrated that the endothelin-1 (ET-1) axis stimulates lymphatic endothelial cells (LEC) and lymphatic vessels to grow and invade. Here we further investigated the effect of ET-1 on lymphatic vessels and evaluated whether ET-1 actions result in the functional activation of lymphangiogenesis. Using highly purified human LEC, characterized for the expression of ET-1 axis members by quantitative real-time PCR, we found that the endothelin B receptor (ETB), upon activation by ET-1, induced matrix-metalloproteinase activation, demonstrating that ET-1 influenced the activity of the proteolytic enzymes required for LEC invasion. Functional assays performed by using intradermal lymphangiography demonstrated that ET-1 promoted the formation of lymphatic vessels and that these vessels were capable of lymphatic flow. ETB blockade with the specific antagonist BQ788 inhibited matrix-metalloproteinase activation and dye transport within the lymphatic vessels, demonstrating that ETB is involved in the regulation of the growth of and in the formation of functional vessels upon activation by ET-1. Our results suggest that ET-1 is a lymphangiogenic mediator and that targeting pharmacologically ETB may be therapeutically exploited in a variety of diseases, including cancer.
Spinella
Francesca
F
Molecular Pathology Laboratory, Regina Elena Cancer Institute, 00144 Rome, Italy.
Caprara
Valentina
V
Garrafa
Emirena
E
Di Castro
Valeriana
V
Rosanò
Laura
L
Natali
Pier Giorgio
PG
Bagnato
Anna
A
D000818:Animals; D000959:Antihypertensive Agents / Q000494:pharmacology; D002465:Cell Movement / Q000187:drug effects* / Q000502:physiology; D002478:Cells, Cultured; D017077:Culture Media, Conditioned / Q000378:metabolism; D042783:Endothelial Cells / Q000166:cytology / Q000187:drug effects* / Q000201:enzymology; D065130:Endothelin A Receptor Antagonists; D065131:Endothelin B Receptor Antagonists; D019332:Endothelin-1 / Q000235:genetics / Q000494:pharmacology*; D004789:Enzyme Activation / Q000187:drug effects; D015870:Gene Expression / Q000235:genetics; D006801:Humans; D008198:Lymph Nodes / Q000166:cytology; D042583:Lymphangiogenesis / Q000187:drug effects* / Q000502:physiology; D008297:Male; D020781:Matrix Metalloproteinase 1 / Q000378:metabolism; D020780:Matrix Metalloproteinase 9 / Q000378:metabolism; D045726:Metalloproteases / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D009842:Oligopeptides / Q000494:pharmacology; D010456:Peptides, Cyclic / Q000494:pharmacology; D010880:Piperidines / Q000494:pharmacology; D044022:Receptor, Endothelin A / Q000235:genetics; D044023:Receptor, Endothelin B / Q000235:genetics
D000959:Antihypertensive Agents; D017077:Culture Media, Conditioned; D065130:Endothelin A Receptor Antagonists; D065131:Endothelin B Receptor Antagonists; D019332:Endothelin-1; D009842:Oligopeptides; D010456:Peptides, Cyclic; D010880:Piperidines; D044022:Receptor, Endothelin A; D044023:Receptor, Endothelin B; C086539:BQ 788; D045726:Metalloproteases; D020780:Matrix Metalloproteinase 9; D020781:Matrix Metalloproteinase 1; C072247:cyclo(Trp-Asp-Pro-Val-Leu)