The findings may point to another way of predicting the behaviour of breast cancer in addition to current tests. (CBC)

A protein that eliminates iron from cells may someday help predict which breast cancer will return.

Low levels of ferroportin, a protein that eliminates iron from cells, are associated with the most aggressive and recurring cancers, researchers found.

In a series of experiments, Dr. Frank Torti, director of the Comprehensive Cancer Center at Wake Forest University Baptist Medical Center in Winston-Salem, N.C., and his colleagues showed aggressive breast cancer cells grew more slowly in a mouse model when researchers artificially increased ferroportin to near normal levels.

When the researchers also looked at ferroportin levels in human breast cancer tissue, they confirmed levels were lowest in the most aggressive areas of cancer.

"Ferroportin expression may help predict whether women who have had breast cancer will relapse or not," Torti said in a release.

A search of the gene activity information for more than 800 women worldwide also showed that ferroportin levels were a strong predictor of the likelihood for a woman's breast cancer to recur, the researchers found.

'Pivotal protein'

"Ferroportin is a pivotal protein in breast biology and a strong and independent predictor of prognosis in breast cancer," the study's authors concluded.

The researchers' next step will be to check larger populations of women.

The lack of ferroportin results in a build-up of iron that allow tumours to grow and perhaps become more aggressive, said study co-author Suzy Torti, an associate professor of biochemistry at Wake Forest Baptist.

She advised against changing the amount of iron in the diet because the study focused on cellular rather than dietary iron.

While the initial results suggest this may be another way of predicting the behaviour of breast cancer in addition to other tests, it remains to be seen if the findings prove to be clinically useful, cautioned Dr. Len Lichtenfeld, deputy chief medical officer for the American Cancer Society. Lichtenfeld spoke to HealthDay News.

The study appears in Wednesday's online issue of the journal Science Translational Medicine.

The research was funded by the U.S. National Institute of Diabetes and Digestive and Kidney Diseases.