Any surefire cure for cancer is still a long way off. The Tufts team doesn't yet know how it would use this light-based treatment to fight cancer in humans, and its existing approach only worked 30 percent of the time. Co-author Michael Levin thinks it might take a decade to solve the "bioelectrical code" and make this practical. However, the very fact that optogenetics worked at all is promising. There could be a day when you can fight cancer just by bathing in a blue aura.