Turning on a key gene inside cancer cells dramatically slows their spread, researchers have found. The discovery could lead to a new “class” of cancer drugs for the future, they say. The team, from Hoffmann-La Roche in New Jersey, US, have nicknamed their drug molecules after the town of Nutley, where their labs are based.They found that their “Nutlins” held back tumour growth by 90% when given to mice in which human tumours were growing.