| Cancer cells die off quickly if they do not have a | | | | growth of new blood vessels. Thus, when the |
| blood supply. Cancers can grow only about 2 | | | | primary cancer is removed, the metastasis grows |
| millimeters and then will stop growing unless they | | | | more because the angiogenic inhibitors are also |
| have more blood vessels. There are certain proteins | | | | removed. It seems quite odd that a cancer would |
| that function to promote the development of new | | | | produce something from itself to stop it from |
| blood vessels. These proteins are specific growth | | | | growing. One would always think it is in the nature of |
| factors that have important roles during | | | | cancer to want to spread and metastasize. Cancer |
| development. An embryo, for example, needs new | | | | will grow in its own area, but will keep any cells from |
| blood vessels that can grow all the way to the arms | | | | growing in other organs. The idea is fanciful, but |
| and legs, in order to develop fingers and toes distally. | | | | cancers do not seem to like having rivals. This is |
| In the case of an injury, one needs blood vessels to | | | | definitely not to suggest that if you have a cancer, |
| grow and heal it. This explains why an injured area | | | | you should ignore it because in won't spread unless |
| appears red. One such protein, which stimulates blood | | | | you undergo surgery. For one thing, it probably isn't |
| vessel growth, is known as vascular endothelial | | | | true for all cancers. For another, the process of |
| growth factor or vascuolotropin. This is secreted by | | | | metastasis after cancer surgery is far from absolute. |
| the cancer cells and then binds to their specific | | | | It doesn't stop the cancer from spreading; it only |
| receptor on the blood vessels and tells them to | | | | controls the metastasis already out there. |
| make more cells. This will initiate the process of | | | | Anti-angiogenic drugs are now being tested in humans |
| angiogenesis - "angio" means vessels and "genesis" | | | | for breast cancer therapy. One of these is |
| which means growth. On a microscopic view, some | | | | thalidomide. This drug blocks the growth of new |
| tumors have more blood vessels than others do. The | | | | blood vessels. This is why when pregnant women in |
| more blood vessels a tumor has, the more blood | | | | the 60s took it to treat insomnia; their children were |
| supply it has, which in turn facilitates its growth. Thus, | | | | often born without arms and legs. But if you are not |
| the more chances the cancer has of spreading, | | | | pregnant and you're an adult who does not need |
| because there are more "roads" to spread out on. | | | | more blood vessels, then you may want to ask your |
| Some researchers think that perhaps we can | | | | oncologist about treatment options involving |
| measure vascular endothelial growth factor in the | | | | thalidomide. Several anti-angiogenesis drugs being |
| blood or in the breast duct fluid to see if there are | | | | tested nowadays may not even have the adverse |
| new blood vessels growing. | | | | effects caused by thalidomide. Some new drugs that |
| A researcher from Boston made the astonishing | | | | were developed for the treatment of arthritis, such |
| discovery that cancers actually secrete not only | | | | as cyclooxygenase 2 inhibitors are also |
| growth promoting proteins, but also growth inhibiting | | | | anti-angiogenic. These drugs are being tested now |
| ones (angiogenic inhibitors). These are substances | | | | for breast cancer prevention. |
| that keep metastasis under control by inhibiting the | | | | |