At the University of Illinois, an engineer teamed up with a veterinarian to test a bone cancer drug delivery system in animals bigger than the standard animal model, the mouse. They chose dogs – mammals closer in size and biology to humans – with naturally occurring bone cancers, which also are a lot like human bone tumors. In clinical trials, the dogs tolerated the highest planned doses of cancer-drug-laden nanoparticles with no signs of toxicity. The nanoparticles also showed anti-cancer activity in mice and dogs.