Angiogenesis affects the progression of cancer by allowing cancer cells to invade tissues nearby, moving throughout the body to form new colonies of cancers known as metastases, explains the National Cancer Institute. Tumors cause blood supply to form by producing chemical signals that stimulate angiogenesis. They can also stimulate normal cells nearby, making them produce angiogenesis-signaling molecules.
Because tumors cannot spread or grow beyond a specific size without the supply of nutrients and oxygen from the blood, researchers are trying to come up with ways to block angiogenesis caused by the tumors, explains the National Cancer Institute. They are studying synthetic and natural inhibitors to slow or prevent the growth of cancer cells, as of 2015.
Angiogenesis is the formation of new blood vessels, a process that involves differentiation, growth and migration of endothelial cells that line inside of walls of blood vessels, explains the National Cancer Institute. This process is controlled by chemical signals that stimulate the formation of new blood vessels or repair of damaged ones. Angiogenesis inhibitors interfere with the formation of blood vessels. In normal circumstances, both the stimulating and inhibiting effects of these chemical signals are balanced by the body so that blood vessels form only where and when they are needed.