Scientists have known for the last decade that a link exists between wound healing and cancer. For instance, in a 1994 experiment at the Lawrence Berkeley National Laboratory, chickens infected with a cancer virus developed tumors in areas of their body that had undergone wounding or scarring, while no tumors developed in infected areas that had not suffered wounding. However, the biological mechanism for this process hasn't been clear.
Now, through studying muscle tissue in breast cancer, scientists in the lab of Whitehead Institute Member Robert Weinberg have discovered the process by which tumors hijack normal wound-healing processes and use them for their own purposes.
Reported in the May 6 issue of the journal Cell, the research began when Akira Orimo, a postdoctoral scientist in Weinberg's lab, investigated the nature of stromal cells found in breast cancer tumors. Stromal cells form the connective tissue in a mammal's organs and glands. They also form the connective tissue inside a tumor. Tumors are composed mostly of cancer cells and stromal cells, and researchers have wondered if the stromal cells in tumors function any differently than they do in normal tissues. Do they simply hold the tumor together the same way they hold a pancreas or a liver together, or do they actively work with the cancer cells in promoting the tumor's growth?
"It turns out the cancer cells are not acting alone," says Weinberg, who is also a Professor of Biology at MIT. "These stromal cells play an important role in helping these cells, and therefore tumors, to grow."