But in their study with rats, the researchers showed it also effectively reduces radiation damage in the normal lungs without protecting the tumor. With amifostine, the possibility exists that we could reduce the incidence of fibrosis. The scientists also found that blood levels of a protein, called TGF-beta, or transforming growth factor beta, can be used to evaluate lung damage and its moderation with drugs like amifostine. Our study showed a strong association that if amifostine reduced lung injury, that levels of TGF-beta were also reduced. Radiation kills cells indirectly, by creating highly reactive oxygen atoms, called free radicals, that can cause enough cumulative damage to DNA that the cell begins to die.
Some chemotherapy drugs work by creating free radicals, too.
Amifostine is one potential agent for protecting normal tissue from the free radicals caused by radiation treatment by decreasing the chances that a cell's DNA will be damaged. While chemotherapy and radiation are supposed to kill cancer cells, inevitably some normal cells are hurt as well. Radiation damage can be minimized through sophisticated techniques such as three-dimensional conformal radiotherapy which, by determining the location, size and relationship to nearby critical organs in three dimensions, allows radiation to be pinpointed to the tumor. But even though damage is minimized, it still happens, said the researchers. Beyond improving quality of life, preventing lung damage could lead to better treatment and improved survival, the researchers said.