Anti-angiogenic approaches to malignant gliomas

Despite advances in multidisciplinary approaches, the prognosis for most patients with malignant gliomas is poor. Malignant gliomas are highly vascularized tumors with elevated expression of vascular endothelial growth factor (VEGF), an important mediator of angiogenesis. Recent studies of bevacizumab, an anti-VEGF monoclonal antibody, alone or associated with chemotherapy, have demonstrated high response rates and prolongation of median and 6-month progression-free survival. Clinical evaluation of several multitarget small molecule tyrosine kinase inhibitors is ongoing. Other promising antiangiogenic compounds are cilengitide and continuous temozolomide. Toxicity is acceptable. Open issues are represented by patterns of tumor progression, resistance mechanisms and biomarkers.