Tumor metastasis, which accounts for the majority of deaths in breast cancer patients, is a process by which cancer cells acquire the ability to invade tissue and survive in other parts of the body.
Dysregulation of the protein TGF-β is known to drive breast cancer metastasis, but the precise molecular mechanisms are unknown. In the Journal of Clinical Investigation, researchers led by William Shiemann at Case Western Reserve University identified a microRNA, miR-181a, that is altered by TGF-β to promote metastasis.
Shiemann and colleagues found that miR-181a repressed the expression of a protein, BIM1, which causes cells to die when they detach from surrounding tissue, a key step in metastasis. Additionally, they determined that increased expression of miR-181a was correlated with decreased overall survival in breast cancer patients.
These findings suggest that miR-181a could potentially serve as a predictive marker for breast cancer metastasis.
TITLE:TGF-β upregulates miR-181a expression to promote breast cancer metastasis