Cancer, like all cells, needs nutrients to survive and proliferate. But because of cancers strive for mass proliferation, sometimes it can outgrow its own resources.
One of the ways cancer can get more nutrient is by connecting to blood vessels that are in the surrounding area. The secretion of these proteins and enzymes can aid in the task, which is called angiogenesis.
VEGF. Vascular endothelial growth factor. This protein is secreted by cancer cells and is responded to by endothelial cells of nearby blood vessels.
VEGFR. Vascular endothelial growth factor receptor. This is the receptor that binds to VEGF. This receptor is located on the endothelial vasculature.
Once VEGF binds to VEGFR, blood vessels begin to grow into the tumor. This gives the tumor more nutrients to grow.
Another problem with angiogenesis besides giving the tumor more nutrient is connecting the tumor with vasculature. If a cancer cell breaks off into the blood stream, it can spread to another organ. This is called metastasis, which is discussed in an upcoming hallmark.
Topics in Cancer Biology 