Keck Medicine of USC scientists have found a promising new therapeutic target for prostate cancer.

The findings offer evidence that a newly discovered member of a family of cell surface proteins called G-protein coupled receptors (GPCRs) promotes prostate cancer cell growth. The protein, GPR158, was found while the researchers were looking for new drug targets for glaucoma.

“When a prostate cancer tumor is in its early stages, it depends on hormones called androgens to grow,” said Nitin Patel, PhD, research scientist at the Institute for Genetic Medicine at the Keck School of Medicine of USC, and corresponding author on the research. “Eventually it progresses to a more lethal form, called castration-resistant prostate cancer (CRPC), and is resistant to drugs that block androgen receptors.  We found that GPR158, unlike other members of the GPCR family, is stimulated by androgens, which in turn stimulates androgen receptor expression, leading to tumor growth.”

The researchers used a conditional Pten knockout mouse model of prostate cancer in collaboration with Keck School researchers Mitchell Gross, Chun-Peng Liao and Pradip Roy-Burman.

The study was published Feb. 18 in the journal PLOS ONE.

The research was produced by the laboratory led by senior author M. Elizabeth Fini, PhD. Other USC research contributors include Tatsuo Itakura, Shinwu Jeong, Ebrahim Zandi, Susan Groshen, Jacek Pinski and Gerhard A. Coetzee.

— Leslie Ridgeway