Scientists Attempt to Double the Efficacy of Radiation Therapy to Reduce Its Side Effects

By reducing the ability of cancer cells to repair the lethal double-strand DNA breaks that radiation therapy causes, scientists at Georgia Health Sciences University are attempting to reduce the amount of radiation needed.

“Radiation is a great therapy – the problem is the side effects,” said William S. Dynan, Ph.D., biochemist and associate director of research and chief of nanomedicine and gene regulation at the GHSU Institute of Molecular Medicine and Genetics. “We think this is a way to get the same amount of cancer cell death with less radiation or use the same amount and maybe cure a patient that could not be cured before.”

Everyday radiation prepares cells to arm themselves with internal mechanisms that prevent lethal breakage, noted Dynan and colleagues at GHSU in a university press release. To target those natural defense mechanisms, the scientists packaged an antibody with folate, which increases the access to most cells.

Previous efforts to destroy the ability of cancer cells to heal radiation damage focused on surface receptors, said Shuyi Li, M.D., a molecular biologist, pediatrician and corresponding author on the study, which was published in the International Journal of Radiation Oncology.

In this study, the scientists went further into the cells by using folate receptors as entry points to target the cell nucleus “where a different chemical environment breaks the bond, freeing ScFv 18-2 to attack the regulatory region of DNA-dependent protein kinase.”

“We are joining a targeting molecule with a cargo,” said Dynan.

Both authors say that this approach could help deliver a number of drugs, along with aiding the effect of radiation. The studies so far have involved human lung cancer cells in culture

To read the press release and learn more about these studies, visit http://news.georgiahealth.edu/archives/4955.