Dr. Johnson’s research is focused on the translational development of experimental therapeutics. His primary research area is focused on natural products including phytochemicals in the areas of cancer, fertility and inflammation. He received an R37 NIH MERIT award for his work on the mangosteen fruit (Garcinia mangostana) for prostate cancer prevention. This work has helped described a novel mechanism of xanthones from the mangosteen for promoting degradation of the androgen receptor, a key target in prostate cancer. He has additional projects including the evaluation of rosemary (Salvia rosmarinus) for colitis and breast cancer. Another project is evaluating green tea extract in combination with fertility promoting drugs for women win uterine fibroids in a multi-site clinical trial. He has also has a collaboration evaluating the use of a topical anti-estrogen in women previously diagnosed with breast cancer.
The goal of his research program is to span preclinical research to early phase clinical trials. A variety of experimental techniques are employed that include the isolation of phytochemicals from plants, mechanistic studies using cell free and cell based assays, pharmacokinetics in small animals and humans, in vivo animal models, and the pharmacodynamics of experimental therapeutics in humans. Since 2007, his research has been continuously funded with support from the National Institutes of Health (NIH), the USDA, the American Cancer Society, as well as non-profit organizations. This funding includes pre-clinical and clinical research projects. Dr. Johnson has been invited to present his research at the Pasteur Institute in Paris, University of Vienna, Central South University in China, Hunan Medical University in China, University of Santo Tomas in the Philippines, and Erciyes University in Kayseri, Turkey.