Like a bounty hunter returning escapees to custody, a cancer-
fighting gene converts organ cells that change into highly
mobile stem cells back to their original, stationary state,
researchers report online at Nature Cell Biology. This newly
discovered activity of the p53 gene offers a potential avenue of
attack on breast cancer stem cells thought to play a central
role in progression and spread of the disease, according to
scientists at The University of Texas MD Anderson Cancer Center.
Long known for monitoring DNA damage and forcing defective cells
to kill themselves, p53 also activates bits of RNA that block
two proteins, the researchers found. This prevents conversion of
epithelial-differentiated cells, which line or cover an organ,
into cells that resemble mesenchymal stem cells when stimulated
by the TGF-β growth factor. Mesenchymal cells are mobile adult
stem cells that can reproduce themselves and differentiate into
a variety of cell types "Blocking this conversion from
epithelial cell to a mesenchyma