Scientists engineer bacteria to eat cancer tumors from the inside out

Researchers are engineering bacteria to invade tumors and consume them from the inside. Because tumor cores lack oxygen, they’re the perfect breeding ground for these microbes. The team added a genetic tweak that helps the bacteria survive longer near oxygen-exposed edges — but only once enough of them are present to trigger the change. It’s a carefully programmed biological attack that could one day offer a new way to destroy cancer.