Researchers at Clemson's Osteoporosis Biomechanics Laboratory will use the funding to study bone loss arising from both radiation therapy and exposure to solar and cosmic radiation. The team expects that the resulting knowledge will assist in the development of countermeasures and bone-loss therapies applicable to both cancer treatment and spaceflight.
Ted Bateman, professor and director of the laboratory, is investigating the molecular and cellular basis for such bone loss. "These grants are a tremendous endorsement of our bone-loss research," he said. "This is an untreated problem in cancer patients undergoing radiation therapy and also a problem we will see as space travel expands to the Moon and Mars."
The US National Institutes of Health is contributing nearly $400,000 to fund the development of an animal model that will enable the Clemson researchers to study radiotherapy-induced bone loss. Concurrently, NASA and its National Space Biomedical Research Institute are providing $1.6 million to support research into the effects of space radiation on astronauts.
The two aspects of the study are similar, in that both involve testing mouse and rat bones after exposure to radiation, but they vary as to the type and amount of radiation involved. Clinical doses of radiation used for treatment of pelvic cancers arise largely from high-dose X-rays, while astronauts in future spaceflight missions will be exposed to lower doses of proton and heavy-ion radiation.
According to a recent article in the Journal of the American Medical Association, there is a 60-200% increase in hip fracture rates following radiation treatment for pelvic cancers in women. Breaking a hip often causes a large decline in quality of life and leads to death in approximately 20% of those affected.
"Past studies confirm that patients who are undergoing radiation treatment for cancer experience more fractures, and hip fractures are particularly damaging to long-term health," Bateman explained. "We hope to provide data that contributes to prevention of these fractures, and ultimately to improve quality of life for cancer survivors."
In terms of the effects of spaceflight on the body, the negative consequences of microgravity on the skeletal system are well documented. "Astronauts on the International Space Station lose bone mass at five times the rate that women lose bone mass following menopause," Bateman noted. The effects of space radiation, however, are not well understood. It's likely that the rapid bone loss caused by weightlessness will be exacerbated by the radiation that astronauts are exposed to on extended space missions.
• See also Space radiation: too many unknowns and A knowledge vacuum on space radiation on medicalphysicsweb.