Protein may prevent radiotherapy-associated oral mucositis

Researchers from the U.S. have reported that genetically engineered mice that produced a certain protein were resistant to radiation-induced oral mucositis, a painful oral ulceration. They hope that their findings will contribute to the development of a new drug that patients can apply topically to mouth sores or that prevents mucositis altogether. According to the researchers, oral mucositis is prevalent to some degree in 40 to 70 percent of patients treated with upper-body radiation. In the most severe form, feeding tubes are required for nutrition and medicine is needed to provide pain relief. As there is currently no FDA-approved treatment available, the researchers think that a new treatment involving the Smad7 protein as a therapeutic agent may help improve quality of life for many cancer patients considerably.

In laboratory tests, mouse models that expressed Smad7 were significantly more resistant to the development of oral mucositis, said Dr Xiao-Jing Wang from the University of Colorado Denver's Department of Pathology. When the protein was applied to the oral cavity directly, the protein showed prophylactic and therapeutic effects against radiation-induced oral mucositis in mice. In particular, it inhibited the growth of oral cancer cells and worked to heal existing ulcers. However, it did not revive cancer cells.

"Thus, we have identified new molecular mechanisms involved in oral mucositis pathogenesis and our data suggests an alternative therapeutic strategy to block multiple pathological processes of this condition," the researchers concluded.