Supplement promoted prostate cancer

DALLAS, Jan. 15 (UPI) -- Hormones in an over-the-counter supplement promoted the progression of prostate cancer in two patients, U.S. researchers report.

The findings, published in Clinical Cancer Research, showed the product was a more potent stimulator of cancer-cell growth than testosterone and attempts to stop the cancer-cell growth with increasing concentrations of the anti-cancer drug bicalutamide proved to be futile.

"Physicians need to ask their patients not only about the prescription drugs they may be taking but -- perhaps ever more importantly -- about the over-the-counter drugs and supplements, which may have a profound impact on certain health conditions," a study author Dr. Claus Roehrborn of University of Texas Southwestern Medical Center in Dallas said in a statement.

The supplement -- not named in the study -- was analyzed when aggressive prostate cancer developed in two patients who took it daily for a few months to develop muscle and enhance sexual performance.

The researchers found the product's label listed ingredients that weren't present, misrepresented the concentrations of the ingredients and failed to list all the steroid hormones. The researchers filed an adverse event report with the U.S. Food and Drug Administration and the agency issued a warning letter to the manufacturers, which led to the product's removal from the market.