Gold Nanoparticles Could Treat Prostate Cancer with Fewer Side Effects than Chemotherapy
Using a compound in tea that is attracted to prostate tumor cells, researchers at the University of Missouri have developed a radioactive gold nanoparticle that kills prostate tumors, without triggering common side effects of prostate cancer therapy. “When we combined the tea compound with radioactive gold nanoparticles, the tea compound helped deliver the nanoparticles to the site of the tumors and the nanoparticles destroyed the tumor cells very efficiently,” explained Kattesh Katti, who led the study. Dr. Katti and his colleagues published their work in the Proceedings of the National Academy of Sciences.
Today, doctors often treat prostate cancer by injecting hundreds of radioactive seeds into the prostate. However, that treatment is not effective when treating an aggressive form of prostate cancer. The size of the seeds and their inability to deliver effective doses hampers their ability to stop this aggressive form of prostate cancer. Dr. Katti and his colleagues solved this problem by using radioactive gold nanoparticles that require one or two injections.
One key component to this research was the discovery that epigallocatechin gallate, a compound in tea, has a particular affinity for prostate cancer cells. The other key component was the discovery that gold nanoparticles of just the right size will stay inside tumors once they reach their target. Radioactive gold was used because of its short half-life – all of it is decayed within three weeks of administration, an optimal time period for this type of radiotherapy.
Tests in mice showed that nearly three-quarters of the nanoparticles remained trapped in the prostate gland after injection into the tumor. Four weeks after injection, the average reduction in tumor volume was approximately 80 percent. Based on the results of these initial tests, the investigators plan larger preclinical studies with an eye on testing this formulation in human clinical trials.
This work, which is detailed in a paper titled, “Laminin receptor specific therapeutic gold nanoparticles (198AuNP-EGCg) show efficacy in treating prostate cancer,” was supported in part by the NCI Alliance for Nanotechnology in Cancer, a comprehensive initiative designed to accelerate the application of nanotechnology to the prevention, diagnosis, and treatment of cancer. An abstract of this paper is available at the journal's website.