In the last 5 years researchers have been examining the genes expressed during breast cancer in order to classify those genes into groups that can reliably predict the outcome of disease. In many cases, exactly how genes with prognostic significance figure into the disease process is not well understood.

In a study appearing in the Journal of Clinical Investigation, Vincent Cryns and colleagues at Northwestern University report how the protein alpha-basic–crystallin, which is commonly expressed in a subtype of breast cancer tumors, is predictive of poor survival in breast cancer patients, independently of other prognostic markers, and also how this protein triggers tumor development.

They reveal that alpha-basic–crystallin is overexpressed in mammary epithelial cells and causes dysregulated growth, changes in cell structure, diminished programmed cell death, and the formation of invasive carcinomas that is linked to activation of the ERK/MAPK signaling pathway. These results may facilitate the development of tailored therapies that are active against this signaling pathway. Ramon Parsons from Columbia University discusses the significance of this study in an accompanying commentary in the same issue.

SOURCE:
Journal of Clinical Investigation, January 4, 2006