As a neurosurgeon at California Pacific Medical Center, Dr. Charles Cobbs has operated on countless brain tumors. But in his research lab in San Francisco, he is hoping to soon attack those tumors in a different way.
Dr. Cobbs and his research partner, Dr. Liliana Soroceanu, first shook up the scientific community with their discovery of the virus CMV being present in the vast majority of brain tumors.
"This is an example of tumor cells from patients where we detected the viral gene product called IE1 in the nucleus of the cells," said Dr. Soroceanu.
"I don't believe this virus causes brain tumors, but I believe that this virus has the potential to be the promoter," said Dr. Cobbs.
In other words, a possible cancer trigger. He says tumor cells often form and dissipate in the human body without causing harm, and it's possible the virus could play a role at that critical point.
"This virus may be able to cause the tumor to be promoted by driving things like blood vessel growth or invasion into the normal brain," said Dr. Cobbs.
The exact role of CMV in brain tumors is still under investigation, but the discovery of the virus and the way it invades the tumor cells, raised an intriguing question. What if there were a drug or some other technique to block it?"
It turns out there are already two such drugs. A team at Duke University, which recently treated Senator Edward Kennedy for a brain tumor, is attempting to coax the body's immune system into attacking the CMV virus, and perhaps the tumor itself.
"Because if you can attack the tumor with your immune system activated, your immune system may come in and actually destroy tumor cells," explained Dr. Cobbs.
At the same time, a team in Sweden is testing a drug called Valcyte on patients with malignant glioma. The drug targets the specific receptor the virus uses to invade the tumor cells.
"It's conceivable that another way to address viral disease would be to block the receptor," said Dr. Soroceanu.
If the early results are encouraging, the researchers are hoping to start their own clinical trial in the Bay Area.
While they say the drug might never become a cure, they believe it could have the potential of significantly slowing a brain tumor's growth.
Once again, the relationship between the virus and brain tumors is not clearly understood at this point, but since their initial discovery, Cobbs and his team have also found indications of CMV activity in colon and prostate cancer cells as well.