A new discovery by medical scientists could help create new therapies for brain cancer. This is the Zika virus, which spreads with mosquito bites. This type of virus is known in the world not for its mortal danger, since no deaths due to this disease have yet been recorded in the world, but for the effect on the brain of an unborn fetus. Zika virus can cross the placenta and cause brain damage in children if a woman becomes infected during pregnancy. However, in their new study, scientists have identified some features of this virus that can destroy cancer cells in the brain.
How does the Zika virus affect the brain?
Since the Zika virus remains poorly understood and little is known about its effect on the human body, scientists have already identified a connection between the disease and the development of the fetal brain. The virus can cause microcephaly in children who were exposed to it in the womb of a sick mother during the embryogenesis stage. Scientists decided to study more closely the mechanisms of action on the human brain and conducted a series of studies that showed that the Zika virus enters brain cells using a special "key". This discovery led researchers to the idea of reprogramming the virus so that it only infects cancer cells in the brain, leaving healthy cells unchanged.
Some cancers, such as glioblastoma, have aggressive forms that often defy conventional medical treatments because the disease converts healthy brain cells into stem cells. Their main advantage is the ability to endlessly divide, while brain cells - neurons stop dividing after just a few repetitions.
According to an article published in the journal Cell.com, scientists will need to make modifications to the common virus in order to make it the safest for healthy brain cells, using the basic principle of destroying cells only on tumor formations.
When the Zika virus enters the body of a pregnant woman, and then into the developing fetus, it inhibits brain development by acting on nerve stem cells and stunting their growth. Based on this, the scientists conducted a study in mice, during which it was found that the Zika virus infects stem cells of glioblastoma rather than normal brain cells. Scientists explain this feature by the presence of special receptors - integrins on the surface of the virus, which they use to adhere to the cells of victims.
With the help of just one kind of integrins, specialists were able to conduct detailed research to study the vulnerability of glioblastoma to Zika infection. Thanks to this, scientists have confirmed the presence of viral "preferences" for brain tumors.
Using a gene editor, CRISPR, the scientists selectively turned off certain genes from glioblastoma stem cells by exposing tumor cells to the Zika virus. As a result of the experiment, scientists were able to find a specific gene carrier of cellular information, thanks to which the Zika virus could recognize cancer cells. The found gene, which was named αvβ5, is found in large quantities on neural stem cells, which are the main targets of the virus.
Based on the research findings, scientists can exploit the weak points of aggressive glioblastomas with the genetically modified Zika virus to fight cancer while preserving healthy cells. Other deadly viruses can also help fight brain cancer. For example, scientists have used a genetically modified polyvirus in the treatment of patients with glioblastoma, while saving the life of 20% of patients undergoing treatment.