A protein key to making a cancer invasive

HOUSTON, Sept. 9 (UPI) -- U.S. researchers say they have identified a protein key to changing a type of active breast cancer into invasive cancer.

The study, published in Cancer Cell, found overexpression of the protein called 14-3-3-zeta starts a process that sets cells loose, the first step in making cancer invasive. This protein may serve as a biomarker identifying high-risk patients for more aggressive treatment.

"Our findings might have broader implications relating to the mechanism of invasion and metastasis in other types of cancer," Dr. Dihua Yu of the University of Texas M.D. Anderson Cancer Center in Houston, said in a statement.

Another protein -- ErbB2 -- helps convert normal breast duct cells into abnormal cells. However, Yu said, these abnormal cells are not invasive when they are locked together in zipper-like fashion by the cell surface protein E-cadherin.

"Overexpression of 14-3-3-zeta is the catalyst for a molecular pathway that strips E-cadherin from the cells, setting the cells loose from each other," said Yu, the study's senior author.

The researchers examined 107 invasive breast cancer cases and found 23 overexpressed both proteins.