LOS ANGELES, March 3 (UPI) -- Using the body's own immune system to fight brain cancer has shown promise in animal studies, new research released early Monday suggests.
Scientists at Cedars-Sinai Medical Center in Los Angeles tested a technique called immunotherapy on rats. The approach is far less invasive than standard brain surgery, which means the treatment would be easier on the patient and allow for quicker recovery.
Dr. John S. Yu, senior researcher and co-director of the center's Comprehensive Brain Tumor Program, injected specially treated bone marrow cells into brain tumors in rats. The tumors represented a very aggressive form of brain cancer called glioma. The bone marrow cells triggered an immune system response by corralling dendritic cells, cogs in the immune system that identify foreign invading molecules and signal the system's T-cells to attack.
As reported in the March 3 issue of the Journal of Immunotherapy, Yu said preliminary results showed the technique could extend survival time for glioma patients. In fact, rats receiving the dendritic cell treatment lived significantly longer than rats that did not, he said. They also continued to survive longer than average even after being injected with tumor cells again after their treatment.
"Based on the study we obtained significant immunological response and whether that translates into better survival, we'll have to wait to see," Yu said. "People are quite dimensionally more complex than rats."
As Yu explained, dendritic cell immunotherapy works like this:
Surgeons remove tumor cells from the brain and then treat them with dendritic cells taken from the rats' bone marrow in the laboratory. The concoction is then re-injected under the skin above the brain, where the dendritic cells ignite an immune system reaction.
An advantage to the immunotherapy approach, Yu explained, is it could also fight cancer that has spread beyond the brain because the dendritic cells are able to enter the lymphatic system, which is located throughout the body.
Another benefit, Yu added, is dendritic cells increase secretion of a powerful natural chemical in the body called Interleukin-12, which can be highly effective in destroying glioma cells. IL-12, as it is commonly known, also is a leading candidate in the search for therapies to treat AIDS.
Immunotherapy is a growing area of cancer research as scientists work to fight ways to get the body to fight its own diseases. However, treating brain cancer this way presents certain obstacles, explained Dr. John Sampson, a professor of neurology at Duke University Medical Center in Durham, N.C.
"This is an innovative approach because it directs the immune system toward the brain cancer," Sampson told UPI. "Dendritic cells are potent activators of the immune system and they may well be successful."
The problem is whether the dendritic cells also cause the immune system to attack healthy brain tissue in addition to the brain tumor. "We're going to face the other problem of how we're going to make them (dendritic cells) specific," Sampson said, adding the approach is "still in its infancy."
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(Reported by Katrina Woznicki, UPI Science News, in Washington)
