Clues Found to Hearing Loss from Chemotherapy

By HSC Staff Writer • Published: January 19th, 2007
Category: Health in a Heartbeat

Children being treated for cancer sometimes suffer hearing loss due to the toxic effects of chemotherapy. But new research suggests health practitioners might one day find ways for them to get it back through drug and gene therapy. And they’ll owe it all to some very special mice.

In affected children, one type of hearing loss occurs when cancer drugs damage the hair cells in the inner ear. When healthy, these cells sprout extremely fine hairs that move in response to sound waves, and set up the electrical impulse that goes to the brain. These are the same cells damaged in adults by prolonged exposure to loud noise.

Scientists from St. Jude Children’s Research Hospital in Memphis who were studying mice say their findings could be a first step toward eventually preventing the loss of these hair cells, or triggering their regrowth, through new drug treatments or gene therapy.

They reported their findings recently in the journal Hearing Research.

The study identified seventeen families of specially bred mice whose offspring carry one or more of a variety of gene mutations that rob their ability to hear high-frequency sounds. The mice seem ideal models for understanding what happens in the ears of affected children undergoing chemotherapy, and eventually which genes are responsible for that damage.

And there’s a bonus finding: The mice models also may advance our understanding of age-related and noise-induced hearing loss in people, as these problems mirror the same inner ear damage experienced by children receiving chemotherapy.