Mapping platinum in the inner ear after chemotherapy
The widely used anti-cancer drug cisplatin has an unfortunate side effect of hearing loss in 40–80 percent of patients. This drug saves lives, but as the number of cancer survivors grows in our society, so do those patients left with permanent hearing loss. Determining the best plan of action to address chemotherapy-induced hearing loss requires a better understanding of how cisplatin affects the inner ear.
IRP researchers led by Lisa L. Cunningham, Ph.D., tested the hypothesis that cisplatin is cleared from different areas of the body at different rates. They used a technique called inductively coupled plasma mass spectrometry (ICP-MS) to measure the amount of platinum (part of the cisplatin drug and not normally present in the human body) in the inner ears of both mice and humans that received the drug. The group found that cisplatin accumulated in specific regions of the inner ear and remained for months or years after drug administration.
This study provides critical insight into potential strategies that would prevent the permanent hearing loss caused by cisplatin chemotherapy. Previous work had assumed the target of any therapeutic strategies would be the sensory cells of the inner ear, but this work shows that the actual target should be the stria vascularis, which regulates the delicate ionic balance of the inner ear.
Andrew M. Breglio, Aaron E. Rusheen, Eric D. Shide, Katharine A. Fernandez, Katie K. Spielbauer, Katherine M. McLachlin, Matthew D. Hall, Lauren Amable & Lisa L. Cunningham. (2017). Cisplatin is retained in the cochlea indefinitely following chemotherapy. Nature Communications. Nov 21;8(1):1654. doi: 10.1038/s41467-017-01837-1.