A placental growth factor variant unable to recognize vascular endothelial growth factor (VEGF) receptor-1 inhibits VEGF-dependent tumor angiogenesis via heterodimerization.
Angiogenesis is one of the crucial events for cancer development and growth. Two members of the vascular endothelial growth factor (VEGF) family, VEGF-A and placental growth factor (PlGF), which are able to heterodimerize if coexpressed in the same cell, are both required for pathologic angiogenesis. We have generated a PlGF1 variant, named PlGF1-DE in which the residues Asp72 and Glu73 were substituted with Ala, which is unable to bind and activate VEGF receptor-1 but is still able to heterodimerize with VEGF. Here, we show that overexpression in tumor cells by adenoviral delivery or stable transfection of PlGF1-DE variant significantly reduces the production of VEGF homodimer via heterodimerization, determining a strong inhibition of xenograft tumor growth and neoangiogenesis, as well as significant reduction of vessel lumen and stabilization, and monocyte-macrophage infiltration. Conversely, the overexpression of PlGF1wt, also reducing the VEGF homodimer production comparably with PlGF1-DE variant through the generation of VEGF/PlGF heterodimer, does not inhibit tumor growth and vessel density compared with controls but induces increase of vessel lumen, vessel stabilization, and monocyte-macrophage infiltration. The property of PlGF and VEGF-A to generate heterodimer represents a successful strategy to inhibit VEGF-dependent angiogenesis. The PlGF1-DE variant, and not PlGF1wt as previously reported, acts as a "dominant negative" of VEGF and is a new candidate for antiangiogenic gene therapy in cancer treatment.
Angiogenesis Lab and Stem Cell Fate Lab, Institute of Genetics and Biophysics Adriano Buzzati-Traverso, Consiglio Nazionale delle Ricerche, Naples, Italy.
Valeria
V
Tarallo
Loredana
L
Vesci
Onofrio
O
Capasso
Maria Teresa
MT
Esposito
Teresa
T
Riccioni
Lucio
L
Pastore
Augusto
A
Orlandi
Claudio
C
Pisano
Sandro
S
De Falco
D000818:Animals; D045744:Cell Line, Tumor; D019281:Dimerization; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000098:blood supply* / Q000235:genetics / Q000378:metabolism / Q000628:therapy; D008565:Membrane Proteins / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D008819:Mice, Nude; D009389:Neovascularization, Pathologic / Q000235:genetics / Q000378:metabolism / Q000628:therapy; D010051:Ovarian Neoplasms / Q000098:blood supply* / Q000235:genetics / Q000378:metabolism / Q000628:therapy; D011485:Protein Binding; D014162:Transfection; D042461:Vascular Endothelial Growth Factor A / Q000037:antagonists & inhibitors* / Q000378:metabolism; D040281:Vascular Endothelial Growth Factor Receptor-1 / Q000378:metabolism*; D023041:Xenograft Model Antitumor Assays
D008565:Membrane Proteins; C098069:PIGF protein, human; C467484:VEGFA protein, human; D042461:Vascular Endothelial Growth Factor A; D040281:Vascular Endothelial Growth Factor Receptor-1