A protein that predicts breast cancer relapse
A new protein responsible for the recurrence of aggressive breast cancers has been spotted by researchers at the Comprehensive Cancer Center at Wake Forest University Baptist Medical Center.
The Wake Forest researchers found that the recurrence of breast cancers is directly linked to low cellular levels of a protein known as ferroportin. Ferroportin eliminates iron from cells. The investigators found the level of the protein in breast cancer cells isolated from patients when they compared them to normal breast cells.
When the research team artificially boosted the protein to near normal levels in an aggressive breast cancer cell line, they found that the cancer cells grew much slower in the presence of added ferroportin.
On further analyzing the levels of the protein in human breast cancer tissue they saw the lowest ferroportin levels occurring in the most aggressive cancers.
The researchers also revealed that decreased ferroportin gene expression was linked with a reduction in breast cancer survival. They came to this conclusion after examining the data pertaining to gene activity profiles in more than 800 women from the four large global studies.
High expression of the ferroportin is linked with a favorable outcome with more than 90 percent of the patients enhancing their lives by ten years or more. "We had a hint that iron might be important in cancer in general, and particularly in breast cancer, but it hadn't been deeply studied," says Dr. Frank Torti, lead author of the new study and director of the Comprehensive Cancer Center at Wake Forest University Baptist Medical Center, Winston-Salem, NC.
In future, testing levels of this protein may help doctors better predict which breast cancers will return and which need more intensive treatment. The study has been published in the online edition of the medical journal Science Translational Medicine.
''One day, this discovery may lead to the development of a tissue test which can help predict recurrences based on ferroportin levels," says Torti while underscoring the fact that for the present, they need to seek a larger group of samples to confirm the results.
Larger studies may eventually help doctors make a more accurate prognosis for breast cancer, using levels of ferroportin along with other markers such as tumour size and lymph node status, Torti said in the published report.