Cancer: Could Zika Be Used to Treat Glioblastoma—the Deadliest Form of Brain Tumor?

The Zika virus, which has caused birth defects in thousands of children over the last three years, could be used to treat one of the most common and aggressive forms of brain tumor.
Harry Bulstrode, a neurosurgeon at the University of Cambridge and Cancer Research UK scientist, is about to begin tests to find out if the virus can destroy glioblastoma cancer cells in the same way it attacks the developing brains of fetuses. If successful, the research could lead to the development of new, effective treatments for this type of brain tumor—and potentially even other types of cancer where stem cells cause the disease to return.
Bulstrode has been awarded £200,000 to conduct the research as part of Cancer Research U.K.'s Pioneer Award.
The latest Zika virus outbreak emerged in 2015, with South American nations worst affected. While it only causes flu-like symptoms in adults, when pregnant women are infected it causes severe birth defects in the developing fetus. One of the conditions it is known to cause is microcephaly, which is characterized by an abnormally small head and an underdeveloped brain.
Justine Alford, senior science information officer at Cancer Research UK, tells Newsweek: "The Zika virus attacks the stem cells of the developing brains of fetuses, leading to a condition called microcephaly. To do this it must bypass the blood brain barrier."
The blood brain barrier is important when it comes to treating neurological diseases like brain tumors. It is a highly selective membrane barrier that separates the blood circulating the body to prevent any potentially toxic substances from entering the brain. This barrier is so effective, however, it often prevents drugs from being delivered to diseased parts of the brain.
While the impact of Zika on the developing brain is devastating, it does not appear to affect fully developed brains. "What Dr Bulstrode did was to put these two bits of information together and consider the possibility that the virus could be used to target the stem cells of brain tumors, without causing damage to the healthy surrounding cells," she says.
Glioblastoma cells closely resemble those seen in the developing brain. As a result, Zika could be introduced to the cancer to attack and destroy cells in the same way.
Bulstrode's experiments will involve testing the Zika against glioblastoma cells in a dish and on mice models. He will look to see how the virus targets stem cells and to see if there are any adverse effects.
"Zika virus infection in babies and children is a major global health concern, and the focus has been to discover more about the virus to find new possible treatments," he said in a statement "We're taking a different approach, and want to use these new insights to see if the virus can be unleashed against one of the hardest to treat cancers.
"We hope to show that the Zika virus can slow down brain tumor growth in tests in the lab. If we can learn lessons from Zika's ability to cross the blood-brain barrier and target brain stem cells selectively, we could be holding the key to future treatments."
Alford says she hopes we will see the Zika virus attacking the tumor cells, but it is far too early to predict any outcome: "He [Bulstrode] will be looking to see what, if any, effect Zika has on these cells. It's impossible to tell how long it will be before the first results. It could happen immediately or it could take a lot longer. This is a very preliminary stage so we just don't know at the moment."
Should tests be successful, the research can be taken forward and could, eventually, lead to a new treatment for glioblastoma—a condition diagnosed in 2,300 people in the U.K. every year, and from which less than five percent of patients survive for five years or more.
If Zika is effective at attacking the cancer stem cells, it could also be used to create treatments for other forms of the disease: "We don't know at this stage what results will come out of this project," Alford says. "If the scientists do find out that Zika could be a promising treatment for glioblastoma, however, perhaps this knowledge could be applied to the treatment of other brain tumors.
"It's also possible that what the researchers discover could be applied more broadly to stem cells—cells that are treatment-resistant and can cause the disease to return—in other types of cancer. But at the moment it's too early to tell whether that will be the case."