FIG. 6.

Runx2 knockdown results in decreased endogenous MMP9 levels in metastatic breast cancer cells. (A) MDA-MB-231 breast cancer cells were treated with siRNAs for Runx2 (25 nM) and for GFP as a control with Oligofectamine for 72 h. Whole-cell lysates were analyzed for Runx2 protein and cdk protein as an internal loading control by Western blotting. (B) mRNA levels of endogenous MMP9 were detected by real-time RT-PCR of total RNA isolated from cells treated with siRNA for Runx2 or GFP or from untreated cells. (C) MMP9 protein activity was detected using gelatin zymography.