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 surface cells and the basement membrane are distinct entities, they affect each other through biochemical interactions. In fact, the cells actually influence the composition of the basement membrane, and the membrane, in addition to serving as a scaffold for cell attachment, regulates cell behavior, proliferation and migration.
The laminin molecule is composed of three chains -- designated alpha (), beta (]) and gamma (^) -- that are linked together in various combinations to form 15 known isoforms or types of laminin. Each isoform has distinct characteristics and functions. Isoforms are known to change in normal tissues at various stages of development but they also have been found to shift in the presence of several invasive cancers. This shift coincides with blood vessel changes that encourage tumor growth and metastasis.
Over the past several years, Cedars-Sinai researchers published several articles related to their findings t
Contact: Sandy Van
Cedars-Sinai Medical Center