Inhibition of PAI-1 expression in breast cancer carcinoma cells by siRNA at nanomolar range.

Plasminogen activator inhibitor type I (PAI-1) plays a central role in metastatic behavior by increasing cells' migratory capacities as shown in several tumoral cell lines. Moreover, in vivo high expression of this factor helps tumoral growth, both by its role in extracellular matrix remodeling and by favoring angiogenesis. High levels of PAI-1 are correlated with bad prognosis in several cancers, particularly in breast cancer.