We know that cancer cells are aggressive, but this takes it to the next level! Researchers at the University of Michigan have shown that breast cancer cells are able to eat other cells and gain new skills. When breast cancer cells were mixed with a type of stem cell, some of the cancer cells swallowed up stem cells. Stem cells are able to change into different kinds of cells and move easily. When the cancer cells ate the stem cells they gained some of these abilities. Importantly, the new hybrid cells were better at spreading (metastasizing) around the bodies of test mice. This could mean that the hybrid cells are behind the spread of at least some human cancers. Working with engineers, the team developed a device that can detect the hybrid cells in animals. If this pans out, the device may be able to predict the spread of cancer in humans too.