Here is the full transcript and summary of William Li’s talk titled “Can We Eat to Starve Cancer?” at TED conference. This talk centers on the concept of angiogenesis, the process by which new blood vessels form from pre-existing vessels. This process is essential for cancer growth and progression.
William Li – Head of the Angiogenesis Foundation
Good afternoon. There’s a medical revolution happening all around us, and it’s one that’s going to help us conquer some of society’s most dreaded conditions, including cancer. The revolution is called angiogenesis, and it’s based on the process that our bodies use to grow blood vessels.
So why should we care about blood vessels?
Well, the human body is literally packed with them: 60,000 miles worth in a typical adult. End to end, that would form a line that would circle the earth twice. The smallest blood vessels are called capillaries; we’ve got 19 billion of them in our bodies. And these are the vessels of life, and, as I’ll show you, they can also be the vessels of death.
Now the remarkable thing about blood vessels is that they have this ability to adapt to whatever environment they’re growing in. For example, in the liver they form channels to detoxify the blood; in the lung they line air sacs for gas exchange; in muscle they corkscrew so that muscles can contract without cutting off circulation; and in nerves they course along like power lines, keeping those nerves alive. We get most of these blood vessels when we’re actually still in the womb.
And what that means is that as adults, blood vessels don’t normally grow. Except in a few special circumstances: In women, blood vessels grow every month to build the lining of the uterus; during pregnancy, they form the placenta, which connects mom and baby. And after injury, blood vessels actually have to grow under the scab in order to heal a wound. And this is actually what it looks like, hundreds of blood vessels all growing toward the center of the wound.
So the body has the ability to regulate the amount of blood vessels that are present at any given time. It does this through an elaborate and elegant system of checks and balances, stimulators and inhibitors of angiogenesis, such that, when we need a brief burst of blood vessels, the body can do this by releasing stimulators, proteins called angiogenic factors that act as natural fertilizer and stimulate new blood vessels to sprout. And when those excess vessels are no longer needed, the body prunes them back to baseline using naturally occurring inhibitors of angiogenesis.