When an army moves forward, it needs to make sure that its SUPPLY LINE is able to keep up with it. The supply line is critical to an army as that is what will provide the army with food rations and ammunition for the soldiers and gasoline for the tanks. Cancers do a similar function. When a cancer grows, it understands that it needs to make more blood vessels to feed itself. The tiny little blood vessel that fed the cancer when the cancer was small can no longer feed it as the cancer grows. So, in response to this, cancers make their own blood vessels. These new blood vessels thus increase the amount of blood that is feeding the cancer. The way that cancers make new blood vessels is by making a protein called a Vascular Endothelial Growth Factor ( abbreviated as VEGF).  Avastin (which is also called Bevacizumab) is medication which is an antibody that is able to “lock on and grab” the VEGF and therefore does not let it “dock” to its receptor on the cell. If VEGF cannot “dock” onto its receptor, it cannot work to make new blood vessels for the cancer to increase its ability to feed itself. Avastin will thus cause the cancer to starve since, as the cancer grows and it cannot make new blood vessels to feed itself, it thus outgrows its blood supply. Like an army that starves because it moves forward faster than the supply line which brings it food, ammunition and gasoline, Avastin starves the cancer by blocking the production of new “supply lines” blood vessels. The cancer can therefore not adequately feed itself and starves. Avastin, thus, helps us to starve the cancer. In a nutshell, this is how Avastin works.