Researchers at the Monash University in Melbourne used a drug compound to selectively activate the prostate's beta estrogen receptor cells. Study co-author Gail Risbridger says this has the effect of targeting for cell death a small but important population of cells in the prostate cancer tumor that are often resistant to conventional therapy and can lead to recurrent incurable disease.

"It is a significant piece of the puzzle that will help medical research in this field -- an achievement that could eventually enhance treatment options for patients around the world with advanced prostate cancer," Risbridger said in a statement.

Risbridger and colleagues used animal models to make the discovery and then replicated the results using human cells and tissues from patients with prostate cancer.

Risbridger said the studies provided proof of the controversial concept that estrogens -- hormones mainly thought to be important for women -- could be good for men and used therapeutically to treat prostate cancer.

The findings are published in the Proceedings of the National Academy of Sciences.