3.5 Tumour vessel targets - Angiogenesis Flashcards
What is angiogenesis?
The process by which a tumour develops blood vessels to supply it with the oxygen and nutrients it needs to grow.
What 3 growth factors are needed for the process of Angiogenesis?
- Vascular endothelial growth factor (VEGF)
- Fibroblast growth factor (FGF)
- Transforming growth factor β
Name one tumour vessel target which drugs attack?
Vascular endotherlial growth factor (VEGF)
Which two types of drug can influence the Vascular endothelial growth factor?
- Monoclonal antibodies
- Tyrosine kinase inhibitors
How do monoclonal antibodies inhibitors influence the vascular endothelial growth factor
- VEGF is required for the process of angiogenesis
- Monoclonal antibodies e.g. Bevacizumab, bind to circulating VEGF, restricting the ability of VEGF to bind with the receptors on the cell surface
- This restricts angiogenesis
How do tyrosine kinase inhibitors block VEGF pathway.
- VEGF is required for the process of angiogenesis
- Tyrosone Kinase Inhibitors e.g. Sunitinib can block the VEGF receptor and downstream VEGF signaling inside th cell which restricts angiogenesis.
Why might a monoclonal and tyrosine kinase inhibitor be used in combination to restrict angiogenesis.
VEGF is required for angiogenesis.
Monoclonal antibodies can bind to the circulating VEGF to prevent it binding with the receptor and can block the VEGF receptor itself, restricting downstram VEGF signaling.
Tyrosine kinase inhibitors can disrupt intracellular VEGF signaling.
Combined both drugs have a synergistic effect, blocking VEGF which restricts angiogenesis, helping to kill the cell by starving it of the blood supply it needs to survive.
Why might monoclonal antibodies be combined with chemotherapy when treating cancer?
- Monoclonal antibodies are cytostatic, they aim to restrict growth and proliferation.
- Chemotherapy is cytotoxic, it aims to kill the cell.
