Updated: Wednesday, June 15, 2005 12:06:57 PM
ANTI-ANGIOGENESIS : "Angio" refers to blood vessels and "genesis" means to grow. Except in special situations, such as during pregnancy, adults rarely grow new blood vessels (angiogenesis). In order to feed themselves, cancer tumors switch on the angiogenic proteins in your body. This theory adheres to the beleif that if you stop the growth of these blood vessels by using anti-angiogenesis proteins, you can literally starve the tumor, thus shrinking and/or killing it. They are thought to work best to prevent a recurrence after a primary tumor has been removed, and are without any of the nasty side effects of chemotherapy. Combinations of proteins seem to work better than those proteins simply given alone. Because the proteins work on blood vessels (not the tumor), the tumor can't become resistant to the proteins, as happens often with chemotherapy. However, it will also prevent proper wound healing after surgery or injury. If the anti-angiogenic compound is stopped, the cancers start growing blood vessels again, and so it is believed that the compound must be given for life.
The most prominent and long term researcher in this field is Dr. Judah Folkman in Boston, who believes anti-angiogenesis may be combined with traditional treatments (chemo, surgery, radiation), as well as other novel treatments (gene therapy, vaccines, anti-sense, etc.). Two anti-angiogenesis proteins are called Endostatin and Angiostatin, which have been tested only on mice. Angiostatin seems to be the natural "brake" to limit cell growth. Endostatin, however, may be more powerful. Vasculostatin is the newest of the anti-angiogenesis proteins. However, a mid-September news release stated that phase I clinical trials on human beings, using Endostatin or Angiostatin, are scheduled to start in early 1999, and will be directed by Dr. Folkman. The type of cancer/s that will be picked for study was not stated. To grow the proteins, EntreMed (a company based in Rockville, MD) is working with pharmaceutical companies (Angiostatin with Bristol-Myers Squibb; Endostatin is not yet designated). Both are extremely difficult to grow, and only very minute amounts are available. For more information about proposed clinical trials, please do not contact Dr. Folkman, as his energies should be concentrated on advancing this discovery. Instead, contact EntreMed by phone (301-217-9858), or via their web site [http://www.entremed.com].
Another researcher at Yale found an anti-angiogenesis compound called TNP-470 (AGM 1470), which is being developed by TAP Pharmaceuticals and Abbott Pharmaceuticals. Contact TAP by calling toll free (888-294-2808), or visit their web site [http://www.tapholdings.com]. Other clinical trials involve thalidomide (the drug given during pregnancy which caused missing limbs in the children born) and 2-methoxyestradial (which kills tumor cells, as well as having anti-angiogenic properties). Other agents are Marimastat, low dose Taxol, CAI, integrin (alpha beta 3) alpha interferon, CM101, pentosan polysulfate, platelet factor 4, and the interleukins, especially interleukin-12.