A University of Iowa faculty member has been awarded funding from the National Institutes of Health to investigate how to prevent permanent hearing loss caused by a widely used anti-cancer drug. 

Cathy Yea Won Sung, assistant professor in the Department of Biology, is the lead investigator on the project. She will aim to prevent permanent hearing loss caused by the chemotherapy drug cisplatin. Although highly effective at killing cancer cells, cisplatin can also damage healthy cells. This includes mechanosensory hair cells in the cochlea, which convert sound vibrations into electrical signals the brain can interpret. Once these hair cells die, they do not regenerate, leading to permanent hearing loss. 

The Sung lab will study the role of a specialized type of immune cell in the cochlea called perivascular macrophages. These cells act as gatekeepers, controlling which substances from the bloodstream enter the cochlea by altering the permeability of the blood vessels. When blood vessels in the cochlea become more permeable, toxic agents such as cisplatin can more easily slip into the cochlea. 

In earlier work with mice, Sung showed that a drug called Pexidartinib reduced the buildup of cisplatin in the cochlea by removing macrophages, including perivascular macrophages. With the award, Sung will study in mice how Pexidartinib affects perivascular macrophages and their role in regulating blood vessel permeability in the cochlea.

Sung hopes the findings could lead to clinical trials in humans. 

“Cisplatin is a highly effective anti-cancer drug,” she says. “Many patients complete treatment with successful outcomes. So, although new cancer therapies are being developed, researchers have focused on identifying strategies to prevent its side effects while continuing to use the drug.” 

The three-year award from the National Institute on Deafness and Other Communication Disorders is for $739,338.