Scientists at the University of Pittsburgh School of Medicine say they may be hot on the heels of the Holy Grail of cancer therapy: a means to protect healthy tissue from the harmful effects of radiation treatment while speeding tumor death. The study, published this week in Science Translational Medicine, could one day be a game changer for cancer patients who receive radiation as all or part of their treatment each year.
Radiation is used, in part, to treat more than 50 percent of all cancer patients. Radiation kills cancer cells. The problem is that it can also demolish healthy ones. In the short-run, the cell death can lead to nausea, vomiting, and skin sores. Long-term radiation exposure, such as in the treatment of breast cancer, can lead to permanent scarring and tissue loss.
The scientists, in collaboration with the National Cancer Institute, found that setting up a roadblock between a specific molecule (called thrombospondin-1) and its cellular parking space, bestowed non-cancerous tissue with nearly complete protection from radiation. “We almost couldn’t believe what we were seeing,” says Jeff Isenberg, MD, and study co-author. “Cells that might have died of radiation exposure stayed viable and functional.” Other studies suggested that monkeying with the same biological pathway slowed tumor regrowth.
Although the mechanism behind the effect is still unclear, the author’s surmise that the road block may raise blood flow to non-cancerous radiated tissue or even make tumor cells more vulnerable to attack by the patient’s immune system. The research team is already sussing out whether or not the same theory would apply for treatment of hypertension, wound healing, and heart attacks.