Cancer has proven to be an extremely elusive target, with tumors developing resistance that allows them to sidestep drugs designed to treat them. However, a group of scientists has now devised a clever new strategy that turns cancer cells suicidal, forcing them to turn against each other.

The key innovation involves introducing two new “switches.” The first switch enables engineered cells to outgrow and dominate the rest of the cancer cell population when exposed to a particular drug. The second switch then unleashes a toxin that kills the now-dominant modified cells along with their unmodified neighbors.