Antiangiogenic activity of the MDM2 antagonist nutlin-3.
Nutlin-3, a nongenotoxic activator of the p53 pathway, dose-dependently (range 0.1 to 10 micromol/L) inhibited the formation of capillaries in an in vivo matrigel assay, as well as the formation of capillary-like structures in an in vitro coculture system composed of endothelial cells surrounded by fibroblasts. In contrast to the chemotherapeutic agent doxorubicin, nutlin-3 showed no induction of apoptosis in vitro either in the cocultures or in isolated vascular endothelial cells, even when used at the highest concentration (10 micromol/L). However, treatment with pharmacological inhibitors of the nuclear factor kappaB and phosphatidylinositol 3-kinase/Akt pathways sensitized endothelial cells to nutlin-3-induced apoptosis. Although nutlin-3 and doxorubicin induced a comparable p53 accumulation in endothelial cells, nutlin-3 was significantly more efficient than doxorubicin in upregulating the p53 target genes CDKN1A/p21, MDM2, and GDF-15, as well as in inhibiting cell cycle progression. However, the predominant in vitro effect of nutlin-3 was its strong antimigratory activity observed at concentrations significantly lower (0.1 micromol/L) than those required to inhibit endothelial cell cycle progression. Taken together, our data suggest that the antiangiogenic activity of nutlin-3 observed in vivo was mainly attributable to inhibition of endothelial cell migration, to some extent attributable to cell cycle arrest, and to a lesser extent attributable to induction of apoptosis.
Secchiero
Paola
P
Department of Morphology and Embryology, Human Anatomy Section, University of Ferrara, Via Fossato di Mortara 66, 44100 Ferrara, Italy. secchier@mail.umbi.umd.edu
Corallini
Federica
F
Gonelli
Arianna
A
Dell'Eva
Raffaella
R
Vitale
Marco
M
Capitani
Silvano
S
Albini
Adriana
A
Zauli
Giorgio
G
D020533:Angiogenesis Inhibitors / Q000494:pharmacology*; D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D002196:Capillaries / Q000187:drug effects; D002453:Cell Cycle / Q000187:drug effects; D002465:Cell Movement / Q000187:drug effects; D002478:Cells, Cultured; D042783:Endothelial Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism / Q000502:physiology; D006801:Humans; D007093:Imidazoles / Q000494:pharmacology*; D051379:Mice; D008810:Mice, Inbred C57BL; D016328:NF-kappa B / Q000037:antagonists & inhibitors; D018919:Neovascularization, Physiologic / Q000187:drug effects; D000081082:Phosphoinositide-3 Kinase Inhibitors; D010879:Piperazines / Q000494:pharmacology*; D047428:Protein Kinase Inhibitors / Q000494:pharmacology; D051057:Proto-Oncogene Proteins c-akt / Q000037:antagonists & inhibitors; D051736:Proto-Oncogene Proteins c-mdm2 / Q000037:antagonists & inhibitors*; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism
D020533:Angiogenesis Inhibitors; D007093:Imidazoles; D016328:NF-kappa B; D000081082:Phosphoinositide-3 Kinase Inhibitors; D010879:Piperazines; D047428:Protein Kinase Inhibitors; D016159:Tumor Suppressor Protein p53; C482205:nutlin 3; D051736:Proto-Oncogene Proteins c-mdm2; D051057:Proto-Oncogene Proteins c-akt