Science daily: Zika virus, causing microcephaly in babies whose mothers were infected during pregnancy by attacking the cells that will give rise to the fetuss cerebral cortex, could be an alternative for treatment of glioblastoma in adults.

This discovery was made by researchers at the University of Campinass School of Pharmaceutical Sciences (FCF-UNICAMP) in São Paulo State, Brazil.

"Zika virus, which has become a threat to health in the Americas, could be genetically modified to destroy glioblastoma cells," said Rodrigo Ramos Catharino, a professor at FCF-UNICAMP and head of the institutions Innovare Biomarker Laboratory.

Through the mass spectrometry analysis of Zika virus-infected glioblastoma cells, scientists also identified the presence of digoxin, a molecule which induced the death of tumoral cells of skin and breast cancer in previous experiments.

The study has been accepted for publication by Journal of Mass Spectrometry.

The researchers infected human malignant glioblastoma cells with Zika and recorded microscope images of them 24 hours and 48 hours after infection in order to observe any metabolic alterations (cytopathic effects) caused by inoculation of the virus. The results showed that the glioblastoma cells displayed moderate cytopathic effects 24 hours after infection, such as rounded, swollen cell bodies and formation of syncytia, masses of cytoplasm in which the membrane contains several nuclei.

The most severe cytopathic effects were observed 48 hours after infection, with a larger number of rounded, swollen cells, more syncytium formation and pronounced loss of cell integrity, all of which denote cell death.

"The cytopathic effects of Zika infection on glioblastoma cells were observed most clearly after 48 hours. Cell morphology was almost totally altered during this period," Catharino said.

That 24 hours after infection, the cells began to produce cardiac glycosides, especially digoxin.

Previous in vitro studies conducted by researchers in other countries showed that this molecule was able to reduce the multiplication and increase the mortality of cells from melanoma, the most aggressive type of skin cancer, as well as breast cancer and neuroblastoma, a tumor that typically affects patients aged 15 or younger.

Because digoxin and other cardiac glycosides have been shown to induce cancer cell death, the researchers concluded that infection by Zika triggered synthesis of the molecule in glioblastoma cells and that this phenomenon is probably one of the factors that lead to neuronal cell death.

Digoxin could be the key molecule that activates glioblastoma cell death during Zika infection.

Based on these findings, the researchers suggest that a genetically engineered Zika virus could eliminate the effects of infection and leave only the viral particles that synthesize digoxin. Thus, the virus could be an alternative for the treatment of glioblastoma, which is highly resistant to chemotherapy drugs.