Types of Tumor Vascularization Angiogenesis Vasculogenic memory -Tumor cells may act like endothelial cells and form vascular-like structures

Types of Tumor Vascularization 3. Vasculogenesis -Differentiation and proliferation from endothelial progenitor cells -They are drawn to the tumor via VEGF -Upon reaching the tumor they differentiate -40% of tumor endothelial, especially lymphomas and colon cancers

Anti-Angiogenic Therapies -Cut off the tumor’s blood flow rather than target the tumor directly -Result: Cut off nutrients the tumor needs to grow

Anti-Angiogenic Therapies

Blocking VEGF Signaling Block Ligand, VEGF Block Receptor, VEGFR-2 Results: -Transient -Stop after treatment is stopped

Vascular Disrupting Agents -Destroy the existing vasculature in the tumor -Possible because of the differences between normal and tumor vasculature Combretastatin

Vascular Disrupting Agents Liposomes coated with NGR peptide (Asparagin, glycine, arginine) would be targeted to the tumor endothelial cell specific marker, aminopeptidase -Liposomes contain the drug Bortezomib (for neuroblastoma) Results: mice lived longer with less toxicity