Glioblastoma cancer stem-like cells (GCSCs) promote themselves proliferation by secreting the vascular endothelial growth factor A (VEGF<sub>A</sub>) in an autocrine manner, positively regulated by phosphodiesterase IV (PDE4).
Glioblastoma in the elderly has been particularly associated with vascular endothelial growth factor (VEGF)-dependent angiogenesis, and early uncontrolled studies suggested that the anti-angiogenic agent bevacizumab (BEV), an antibody to VEGF, might be preferentially active in this patient population.
Vascular endothelial growth factor (VEGF)-A and VEGF receptor expression in the peritumoral brain zone (PBZ) differs from that in the tumor core (TC) of glioblastoma.
Activation of the formylpeptide receptor (FPR), a G-protein-coupled receptor, by its chemotactic peptide ligand N-formylmethionyl-leucyl-phenylalanine (fMLF) promotes the directional migration and survival of human glioblastoma cells. fMLF also stimulates glioblastoma cells to produce biologically active VEGF, an important angiogenic factor involved in tumor progression.
As a second line treatment of glioblastomas, the vascular endothelial growth factor (VEGF) antibody bevacizumab is administered in combination with the TOP1 inhibitor irinotecan and glioblastoma cell levels of TIMP-1 could therefore potentially influence the efficacy of such treatment.
Based on previous data on an autocrine function of VEGF in Flt-1-expressing glioblastoma cells we hypothesise that the X-ray radiation induced upregulation of VEGF might result in a downregulation of tumour cell proliferation and thus lead to a reduced sensitivity to radiation therapy.
Bevacizumab (Bev), a humanized anti-VEGF antibody, is associated with the improvement of progression-free survival and performance status in patients with glioblastoma.
Bevacizumab (BEV), a humanized monoclonal antibody that blocks the effects of vascular endothelial growth factor A, has produced impressive response rates for recurrent GB and has been approved as second-line therapy.