Men with prostate cancer who take statin drugs while undergoing androgen deprivation (ADT) kept their disease under control longer than those who didn't take statins, according to a clinical trial conducted by Dana-Farber Cancer Institute.

The study, which was published by JAMA Oncology, found that men who were taking cholesterol-lowering statin drugs at the beginning of their androgen deprivation therapy went a median of 27.5 months before their disease began to progress. The cancers of men who didn't take statins began to worsen in 17.4 months. Of the 926 patients who participated in the trial, 70 saw their disease progress during the six-year study.

"This median 10-month benefit in delaying disease progression suggests that statins could be a valuable addition to our current therapies for prostate cancer," said medical oncologist Lauren Harshman in a press release. "These results are supported by multiple prior epidemiologic studies demonstrating that statin use may be associated with improved outcomes in prostate cancer, but require validation."

The study was spurred by laboratory studies that suggested that ADT, which reduces the body's amount of androgen and prevents cancer cells from using it to grow and spread, could delay prostate cancer in patients who took statins. ADT is the main treatment for patients whose cancer is hormone-sensitive and has spread beyond the prostate gland.

Previous research had found that a protein called SLCO2B1 helps drugs and hormones enter cells. One of the chemicals, called dehydroepiandrosterone sulfate (DHEAS), is a precursor of testosterone, which stimulates the growth of prostate cancer.

Statins also rely on SLCO2B1 to enter cells. Researchers found that statins could monopolize available SLCO2B1, which in effect, interferes with amount of DHEAS that can enter prostate cells.

"We present a plausible mechanism by which statins may work in prostate cancer by decreasing the tumor's available androgen pool and thus improving patient outcomes," says study senior author Philip Kantoff, MD. "Further study is required to validate our findings."