Scientists have discovered that electrical currents may make Natural Killer (NK) cells — our very own cancer-killing immune cells — even better killers, which could have significant implications for treating some cancers. The scientists found that Tumour Treating Fields (TTF) in the laboratory (which mimic exposure of brain tumors to electric currents via a simple hat worn by patients) evoked an even more deadly response from NK cells. They hope their promising findings may open the door to new combined therapies for people living with certain brain tumors, such as glioblastoma.