Multiple receptor tyrosine kinases regulate HIF-1alpha and HIF-2alpha in normoxia and hypoxia in neuroblastoma: implications for antiangiogenic mechanisms of multikinase inhibitors.
Oncogene
; 29(20): 2938-49, 2010 May 20.
Article
en En
| MEDLINE
| ID: mdl-20208561
ABSTRACT
Novel treatment approaches are needed for children with advanced neuroblastoma. Studies with neuroblastoma cells have indicated the presence of a hypoxia-driven vascular endothelial growth factor (VEGF)/VEGF receptor (VEGFR)-1 autocrine loop modulating hypoxia-inducible factor-1alpha (HIF-1alpha). Whether other receptor tyrosine kinases (RTKs) are capable of modulating HIF-1alpha levels and whether RTKs can regulate HIF-2alpha as well is largely unknown. We evaluated neuroblastoma cell lines for expression of various RTKs. Although cell lines were heterogeneous in the expression of VEGFR-1, -3, c-Kit and RET, most cells expressed PDGFR-alpha and -beta. Ligand-induced activation of multiple RTKs upregulated HIF-1alpha levels, whereas activation of VEGFR-1 alone upregulated HIF-2alpha. Multitargeted tyrosine kinase inhibitor sunitinib reduced hypoxia-induced rises in HIF-1alpha and HIF-2alpha through mechanisms involving effects on both mRNA levels and protein stability. In addition, sunitinib and sorafenib had direct effects on tumor cell viability in vitro. In a neuroblastoma xenograft model, tumor growth inhibition by sunitinib was associated with inhibition of angiogenesis and reduced HIF-1alpha levels. These findings show that multiple RTKs may regulate the HIF axis in normoxia and hypoxia and suggest that multikinase inhibitors may exert antiangiogenic effects not only by direct effects on endothelial cells, but also by blocking compensatory hypoxia- and ligand-induced changes in HIF-1alpha and HIF-2alpha.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Proteínas Tirosina Quinasas Receptoras
/
Inhibidores de la Angiogénesis
/
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico
/
Subunidad alfa del Factor 1 Inducible por Hipoxia
/
Hipoxia
/
Neuroblastoma
Tipo de estudio:
Prognostic_studies
Idioma:
En
Revista:
Oncogene
Asunto de la revista:
BIOLOGIA MOLECULAR
/
NEOPLASIAS
Año:
2010
Tipo del documento:
Article
País de afiliación:
Estados Unidos