In a healthy individual, we know that angiogenesis is a stop and go process, similar to the way an automobile runs says senior author Raghu Kalluri, Ph.D., of the Department of Medicine and the Program in Matrix Biology at BIDMC and Associate Professor of Medicine at Harvard Medical School. No matter how fast and powerful a car is, it is not useful if it can only accelerate and cannot stop. The same principle applies to the growth of new blood vessels in the absence of an effective set of brakes, what is an extremely useful tool under normal circumstances becomes a serious problem for patients with cancer.
During the process of angiogenesis, a single layer of endothelial cells lining the inside of blood vessels divide and break off from the vessels membrane, forming tubes that become new capillaries. In women, this process occurs monthly during the menstrual cycle, as the lining of the uterus is rebuilt. Angiogenesis is also important to both men and women to repair tissue following an injury. In both of these cases, the process is maintained by a careful balance of proangiogenic and antiangiogenic factors. When this balance is disrupted, the capillaries grow unchecked, such as during tumor growth or in conditions such as macular degeneration, which leads to vision loss due to overgrowth of blood vessels in the eye.
We know that when a tumor forms, the endothelial cells divide more rapidly and spread much more quickly than they would during the normal course of blood vessel format
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Contact: Jerry Berger
jberger@caregroup.harvard.edu
617-632-8062
Beth Israel Deaconess Medical Center
3-Jan-2002