Xing became interested in kava because of epidemiological observations showing that nations with high kava consumption — like Samoa, Vanuatu and Fiji — have lower overall cancer incidence rates, particularly in lung, colon and pancreatic cancers. Cancer rates were also observed to be lower in men than in women, which is opposite to the general trend in the rest of the world, while kava is traditionally more popular in men than women.
Stimulated by these phenomena, kava has been hypothesized to reduce cancer risk. Over the past 15 years, Xing has gradually focused his research and passion on cancer prevention. With kava as a guiding star, he is exploring how to reduce cancer risk among high-risk individuals.
To date, Xing has used various animal models demonstrating kava’s potential to prevent tumorigenesis — the development of cancerous tumors — in the lung, prostate and colon, which are three of the four cancers with the highest incidence in the U.S. His research currently focuses on lung cancer. Using a tobacco carcinogen-induced lung cancer animal model, kava demonstrated outstanding efficacy, completely blocking lung tumor development in the models under experimental conditions.
As a medicinal chemistry group, Xing’s lab has identified kava’s active ingredients, and their investigation has revealed that kava reduces DNA damage caused by tobacco carcinogen. Such research has caught the interest of the National Cancer Institute, which is funding Xing’s lab with a translational five-year, $1.8 million grant.
Xing and his colleagues have concluded a pilot kava clinical trial among smokers. The results, consistent with the data from animal models, further bolsters kava’s potential to reduce lung cancer risk among smokers. The researchers were also surprised to find the trial participants’ tobacco use and dependence decreased, likely because kava relieved their stress.
As a significant portion of cancer survivors continue to smoke after cancer treatment, the UF Health Cancer Center has funded a pilot trial to evaluate kava’s ability to reduce the risk of cancer recurrence in head and neck cancers survivors.