A compound found in the bark and leaves of the magnolia tree has been shown to be a promising potential treatment for head and neck cancers that kill more than 20,000 Americans every year.

Researchers from the Birmingham Veteran Affairs Medical Center and the University of Alabama at Birmingham have determined the compound — honokiol — blocked a protein that drives tumor growth in squamous cell head and neck cancers, most commonly caused by tobacco and alcohol use, Medical News Today reports.

The compound has long been used in traditional Chinese and Japanese medicine for the treatment of anxiety and stress. Recent scientific studies have also found it has anti-cancer properties, with researchers finding it prevents or reduces tumor growth in breast, skin, prostate, and lung cancer.

For the latest study, lead researcher Santosh K. Katiyar, M.D., of the Comprehensive Cancer Center and the departments of chemistry and dermatology at UAB, examined the effects of the compound on mice and on human tumor cells.

The results, published in the journal Oncotarget, indicated honokiol halted the growth of tumors in both the human cancer cell lines and the mice.

"Conclusively, honokiol appears to be an attractive bioactive small molecule phytochemical for the management of head and neck cancer which can be used either alone or in combination with other available therapeutic drugs," said Dr. Kativar.