Study: Gene Might Control Breast Cells

U.S. scientists say they have discovered an unsuspected role for a gene known to be one of the best predictors of human breast cancer outcome.

The gene, called GATA-3, is in a family of genes that guides development of stem cells into mature cells. Now University of California-San Francisco researchers have determined GATA-3 is also required for mature mammary cells to remain mature in the adult.

The scientists discovered that without GATA-3, mature cells revert to a less specialized, undifferentiated state characteristic of aggressive cancer. That, they said, suggests the gene might play a key role in the development of breast cancer.

Perhaps the loss of GATA-3 and subsequent failure to maintain this mature state is what leads to loss of differentiation during cancer progression, said Hosein Kouros-Mehr, a UCSF medical student and lead author of the study. The finding suggests the differentiation, or maturity, of cells is a process that must be actively maintained throughout the lifetime of an organism.

The study appears in the Dec. 1 issue of the journal Cell.