Brain Cancer Vaccine Shows Promise

April 19, 2002 -- An experimental new cancer vaccine may one day help prevent brain tumors in those at risk. A new study shows the vaccine completely prevented brain cancers from forming in laboratory rats.

"The results of our study are very encouraging. The 100% protection is pretty dramatic," says study author Linda Liau, MD, assistant professor of neurosurgery at UCLA, in a news release. "However, we don't yet have ways to determine who is at high risk of developing brain tumors. So our next step is to begin preliminary testing of this vaccine as a possible treatment strategy for brain tumors."

Although the results are promising, researchers say human tests are still several years away. The findings appear in the April 15 issue of the journal Cancer Research.

Researchers say there is critical need for new brain cancer treatments. The disease affects more than 17,000 Americans each year and it is almost always fatal within two years.

The vaccine is designed to boost the immune system's ability to fight off specific proteins that are produced by tumors. But the problem is that every brain tumor produces different kinds of proteins, so it's impossible to know beforehand which ones should be included in the vaccine for each individual patient.

But Liau says the vaccine may work, in part, by teaching the immune system how to recognize the brain cancer cells as abnormal and attack them. The researchers did this by using the bacteria Listeria to transport the tumor proteins. This helped the immune system recognize the proteins as abnormal cells.

Using this approach, "the immune system can become a better detective and will start to recognize and attack brain tumor cells with other kinds of [proteins]," Liau says.

UCLA researchers are now planning to refine the vaccine and develop a form of it that can be safely used in humans. The hope is that the vaccine may eventually be used to provide a targeted treatment against existing brain tumors as well as to prevent tumors in persons at risk.