Angiogenesis -- the formation of new blood vessels -- plays an important role in the growth and spread of cancer. Because of this, scientists are trying to find ways to stop or slow down this process. Substances that inhibit this process appear to be effective against cancer in animal models, but whether this will translate to humans is not yet known.
Angiogenesis means the formation of new blood vessels. This process is controlled by certain chemicals produced in the body. These chemicals stimulate blood vessels or form new ones. Other chemicals, called angiogenesis inhibitors, signal the process to stop.
Angiogenesis plays an important role in the growth and spread of cancer. New blood vessels "feed" the cancer cells with oxygen and nutrients, allowing these cells to grow, invade nearby tissue, spread to other parts of the body, and form new colonies of cancer cells.
Because cancer cannot grow or spread without the formation of new blood vessels, scientists are trying to find ways to stop angiogenesis. They are studying natural and synthetic angiogenesis inhibitors, also called anti-angiogenesis agents, in the hope that these chemicals will prevent the growth of cancer by blocking the formation of new blood vessels. In animal studies, angiogenesis inhibitors have successfully stopped the formation of new blood vessels, causing the cancer to shrink and die.
Whether these will be effective against cancer in humans is not yet known. Various angiogenesis inhibitors are currently being evaluated in clinical trials (research studies in humans). These studies include patients with:
- Breast cancer
- Prostate cancer
- Brain cancer
- Pancreatic cancer
- Lung cancer
- Stomach cancer
- Ovarian cancer
- Cervical cancer
- Some leukemias and lymphomas
- AIDS-related Kaposi's sarcoma.
If the results of clinical trials show that angiogenesis inhibitors are both safe and effective in treating cancer in humans, these agents may be approved by the U.S. Food and Drug Administration (FDA) and made available for widespread use. The process of producing and testing angiogenesis inhibitors is likely to take several years.