WEDNESDAY, July 27, 2005 (HealthDay News) -- Researchers say they've developed an anticancer "smart bomb" that delivers a lethal dose of drugs directly to tumors.
This tiny agent, called a "nanocell," enables precision targeting of the tumor while leaving adjacent healthy tissue unharmed, according to researchers at the Massachusetts Institute of Technology in Boston.
In research with mice, the nanocell proved safe and effective, prolonging survival in animals with melanoma and lung cancer, according to a study in the July 28 issue of Nature.
"We brought together three elements: cancer biology, pharmacology and engineering," research team leader Ram Sasisekharan, a professor in MIT's biological engineering division, said in a prepared statement.
The researchers described the nanocell as a balloon within a balloon that resembles an actual cell. The outer membrane of the nanocell is loaded with an anti-angiogenic drug designed to choke off the tumor's blood supply. The inner membrane of the nanocell is loaded with chemotherapy drugs.
A "stealth" surface chemistry on the nanocell enables it to avoid attracting the attention of the immune system. While the nanocells are small enough (200 nanometers) to pass through tumor blood vessels, they're too large to pass through the pores of healthy, normal vessels.
Once inside the tumor, the nanocell's outer membrane disintegrates, releasing the anti-angiogenic drug and causing the collapse of the blood vessels feeding the tumor. The collapsed blood vessels trap the nanocell inside the tumor. The nanocell then slowly releases its cache of chemotherapy drugs.
Mice treated with the nanocell therapy survived beyond 65 days while mice treated with the best current therapy survived 30 days. Untreated mice survived for about 20 days, the researchers report.
"It's an elegant technique for attacking the two compartments of a tumor, its vascular system and the cancer cells," angiogenesis pioneer researcher Judah Folkman, of Children's Hospital Boston, said in a prepared statement.
The American Academy of Family Physicians has more about cancer treatments.