title: Current perspectives on antiangiogenesis strategies in the treatment of malignant gliomas.
abstract: Progressive tumor growth depends on angiogenesis to sustain metabolic needs of tumor cells, thus providing a potential target for cancer therapy. Malignant gliomas have retained their dismal prognosis despite aggressive multimodal conventional therapeutic approaches, illustrating the need for novel therapeutic strategies. Gliomas are a suitable tumor type for probing angiogenesis inhibition as their proliferation is characterized by a prominent proliferative vascular component. In the present review, we discuss the current status and future directions of angiogenesis inhibition in gliomas. We focus on recently developed approaches inducing an antiangiogenic response such as targeted gene delivery, protein tyrosine kinase inhibitors and encapsulated producer cells. Although several of these modalities have shown promising results on their own, the true potential of these novel approaches lies in their combined use with radiotherapy or 'metronomically scheduled' chemotherapy. A combined approach potentially counteracts the selective pressure on hypoxia-resistant malignant tumor cells, circumvents endothelial resistance induced by local cytoprotective responses and enhances the delivery of cytotoxic agents by normalizing vascular physiology. Surrogate markers of angiogenesis currently under study may provide accurate assessment of response in individual patients. Future research on endothelial markers expressed on tumor-associated vasculature as well as endothelial responses to cytotoxic treatment will provide new avenues for molecularly targeted therapy in malignant gliomas.
authors.affiliation: Department of Pathology, Academic Medical Centre, University of Amsterdam, Amsterdam, The Netherlands.
authors.forename: Marnix
authors.initials: M
authors.lastname: Jansen
authors.forename: Philip C
authors.initials: PC
authors.lastname: de Witt Hamer
authors.forename: Antonella N
authors.initials: AN
authors.lastname: Witmer
authors.forename: Dirk
authors.initials: D
authors.lastname: Troost
authors.forename: Cornelis J F
authors.initials: CJ
authors.lastname: van Noorden
mesh_terms: D020533:Angiogenesis Inhibitors / Q000627:therapeutic use*; D042682:Angiopoietins / Q000378:metabolism; D000818:Animals; D001932:Brain Neoplasms / Q000235:genetics / Q000628:therapy*; D002986:Clinical Trials as Topic; D003131:Combined Modality Therapy; D004730:Endothelium, Vascular / Q000378:metabolism; D015316:Genetic Therapy / Q000379:methods; D005910:Glioma / Q000235:genetics / Q000628:therapy*; D006801:Humans; D008954:Models, Biological; D009389:Neovascularization, Pathologic / Q000235:genetics / Q000503:physiopathology*; D040262:Receptors, Vascular Endothelial Growth Factor / Q000378:metabolism; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism
chemical_list: D020533:Angiogenesis Inhibitors; D042682:Angiopoietins; D042461:Vascular Endothelial Growth Factor A; D040262:Receptors, Vascular Endothelial Growth Factor