Figure 1.

Function of angiogenic factors in normal and neoplastic conditions: A) in normal conditions, Ang1 binds its receptor of Tie2 and consolidates vessel wall but in B) malignant conditions, Ang2 level is increased with an opposite function to Ang1, destabilizing and degenerating the vessel, which results in angiogenesis due to the presence of secretory VEGF factor. Blood vessels are a factor for transport of malignant cells to other sites to cause metastasis. G-CSF affects leukemia cells and causes their growth. LCs, leukemia cells; VEGFR, vascular endothelial growth factor receptor; VEGF, vascular endothelial growth factor; Ang1,2, angiopoietin1,2; PDGF, platelet derived growth factor; bFGF, basic fibroblast growth factor; G-CSF, Granulocyte colony stimulating factor; TNF-α, Tumor necrosis factor-α.