A molecular change that takes place during the progression of malignant brain tumors also occurs in breast cancer, according to a study conducted at Cedars-Sinai's Maxine Dunitz Neurosurgical Institute. The shift appears to be part of a process that enables tumors to develop the new blood vessels they need to grow rapidly, migrate and invade other tissue.

Although the switch is evident even in an early stage of breast cancer when cells are proliferating but not infiltrating normal tissue, it becomes more pronounced as the cancer progresses to the invasive stage. Therefore, the genes involved and the proteins they produce may become markers that physicians can use to determine disease progression and patient prognosis. They also may become targets for new therapies.

The switch affects proteins called laminins, which are components of the "basement membrane" of blood vessels, a thin mesh-like structure beneath the cells of the blood vessel surface (epithelium).

"Although the exact mechanism causing these shifts has not yet been defined, the overexpression of laminin-2, laminin-8 and laminin-10 strongly relates to the development of breast cancer-induced neovascularization and tumor progression," said Keith L. Black, M.D., director of the Maxine Dunitz Neurosurgical Institute and one of the paper's authors. This "may be useful in diagnosing the stage and progression of breast cancer, predicting additional tumor growth and metastasis, and determining patient prognosis," he adds.

SOURCE:
Cedars-Sinai Medical Center (http://www.cedars-sinai.edu)