Spit Happens

Gene known as Aquaporin 1 was shown potential with oral cancer patients and chronic dry mouth

(RxWiki News) Treating head and neck cancers often involves radiation therapy. These strong x-rays can damage the glands that make saliva, which in turn, causes dry mouth. A therapy is being developed that may help spit happen more easily.

An early clinical trial has demonstrated that using gene therapy on the salivary gland is safe.

In this small study, head and neck patients were better able to keep moisture in their mouths, something that radiation often takes away.

"Ask your oncologist about clinical trials."

It was the experiments of scientists at the National Institute of Dental and Craniofacial Research (NIDCR) that uncovered this association. One gene known as Aquaporin-1 was shown to have potential use in helping oral cancer patients with chronic dry mouth.

Aquaporin-1 works with a cell protein that helps move fluids such as saliva which is made in the salivary gland. Researchers say the salivary gland is a great target for gene therapy, because once inside, genes don’t have an easy way to get into the bloodstream.

Bruce Baum, DMD, PhD, lead study author and recently retired NIDCR scientist, has spent more than two decades studying this specific type of gene therapy.

“You cannot imagine how fulfilling it is to jot down an idea on a napkin in 1991 and then see it enter a clinical trial and help people,” Dr. Baum said in a press release.

For this study, which began in 2008, 11 head and neck patients had the Aquaporin-1 gene injected directly into their salivary gland.

Within the 42-day study window, five participants were able to make and secrete more saliva to keep their mouths moist.

There were no serious side effects in the six who did not benefit from the therapy.

More research is needed to learn if this approach can produce meaningful results. Dr. Baum said that “these data will serve as stepping stones for other scientists to improve on this first attempt in the years ahead. The future for applications of gene therapy in the salivary gland is bright.”

This study was published in the November issue the Proceedings of the National Academy of Sciences.

Review Date: 
November 18, 2012