A deadly type of brain tumor and Zika-related brain damage in developing fetuses are devastating brain conditions that, at first glance, may seem unrelated. However, thanks to new research, their paths seem to cross in a way that could benefit patients. A new study has shown that Zika kills brain cancer stem cells, the kind of cells most resistant to treatment in patients with glioblastoma, a deadly brain tumor diagnosed in about 12,000 people in the US each year.