When Cancer Glows

By Drs. David Niesel and Norbert Herzog, Medical Discovery News When surgeons remove a cancerous tumor, their goal is to remove all of it. But determining which cells are cancerous and which are healthy is tough. A pathologist's job is to quickly examine the excised tissue to determine whether all of the tumor has been removed. Sometimes, despite a medical team's best efforts, later MRI and CT scans reveal that cancer cells have been left along the margins. As a solution, scientists are looking for ways to light up cancer cells so that surgeons can see them more easily during an operation. Scientists at the Massachusetts Institute of Technology invented a blue fluorescent dye called LUM015. They injected the dye into 15 breast cancer patients at the Duke University School of Medicine before surgery. The doctors were able to successfully remove the tumors in each of these women, and none of them experienced any adverse reactions. The dye, LUM015, works because it is cut by a protease enzyme called cathepsins. In normal cells, cathepsins' job is to cut and degrade proteins. However, in many tumors, cathepsins are made in higher amounts and are sometimes secreted by cells. Once secreted, these cathepsins rest on the surface of cell and then serve as a marker to identify tumor cells. These extra cathepsins also begin to digest the extracellular matrix or ECM. The ECM is a mesh of molecules that holds cells in place. Once the ECM is gone, cells lose their ability to stay in ...
Source: Science - The Huffington Post - Category: Science Source Type: news