The January issue of Scientific American, now available in electronic form, will have an interesting article about how antiangiogenic drugs (drugs that inhibit blood vessel growth) such as Avastin actually work in cancer therapy. It turns out that it’s not just that they reduce the overall blood supply to a tumor, although that is one of their actions. In fact, they also normalize the remaining vessels, pruning them and improving their permeability properties. As a result, antiangiogenic drugs improve the effectiveness of other cancer treatments such as chemotherapy, because now the chemotherapeutic drugs are better able to reach the tumor cells.
But there is only a window of opportunity in which the combination of antioangiogenic drugs and other therapies is particularly effective, because the antiangiogenic drugs are hard on blood vessels throughout the body and because tumors may eventually lose their responsiveness to the drugs. Nevertheless, our improved understanding of how antiangiogenic drugs actually work is opening new avenues for developing more specific cancer treatment regimens. To learn more, read the original article (“Taming Vessels to Treat Cancer”, by Rakesh K. Jain. Scientific American Jan. 2008, pp. 56-63).
