VEGFA and glioma: Neoangiogenesis in gliomas is realized through a complex molecular mechanism focused on vascular endothelial growth factor (VEGF), angiopoietin-1 (Ang-1), angiopoietin-2 (Ang-2), hypoxia, and so forth [28]; that does not exclude the possibility that bone marrow-derived endothelial progenitor cells [29, 30] or mesenchymal stem cells [31] participate in the process.