Scientists at University College-London report that they have engineered adult stem cells to seek out and destroy cancer cells in mice. Mesenchymal stem cells, a type of adult stem cell found in bone marrow and connective tissue, have been shown to be good vectors to carry factors to different parts of the body, as well as seek out cancer cells throughout the body. The research team, led by Dr. Michael Loebinger, altered these adult stem cells to express the cancer-killing protein TRAIL (TNF-related apoptosis-inducing ligand), which causes the death only of cancer cells. In the lab, the cells were able to find and kill cells from lung, squamous, breast, and cervical cancer. They also injected the cells into mice with breast tumors and showed they were able to safely kill the tumors but leave healthy tissue intact. Results were presented at the American Thoracic Society's 105th International Conference in San Diego.