Researchers from Keck Medicine of the University of Southern California (CA, USA) have identified a potential new therapeutic target for prostate cancer. While searching for new drug targets for glaucoma, the researchers found evidence that the newly discovered G-protein-coupled receptor GPR158 promotes prostate cancer cell growth.
According to the American Cancer Society, prostate cancer is the second most common cancer in American men, with more than 27,000 deaths predicted in 2015. Current statistics indicate that one in seven men will be diagnosed with prostate cancer during their lifetime.
“When a prostate cancer tumor is in its early stages, it depends on hormones called androgens to grow,” explained Nitin Patel, research scientist at the University of Southern California. “Eventually it progresses to a more lethal form, called castration-resistant prostate cancer, and is resistant to drugs that block androgen receptors. We found that GPR158, unlike other members of the G-protein-coupled receptor family, is stimulated by androgens, which in turn stimulates androgen receptor expression, leading to tumor growth.”
The researchers also discovered that GPR158 is associated with neuroendocrine transdifferentiation of epithelial prostate tumor cells, which has a key role in the development of resistance to current androgen receptor-targeted therapies. It was also found that patients with increased GPR158 expression experienced disease relapse and thus the team believe that GPR158 is a promising new target for prostate cancer drugs.
The Keck team are now looking to explore the molecular pathways involved in the functional role of GPR158 in neuroendocrine transdifferentiation and the development of castration-resistant prostate cancer, and will be investigating GPR158-targeted antibody therapeutics.
Written by Ellen Clarke