Figure 1.

TGF-β1 induces MMP-9 in three human prostate cancer lines. ND-1 cells (lanes 1 and 2), DU145 cells (lanes 3 and 4), and TsuPr1 cells (lanes 5 and 6) were treated without (−) and with (+) TGF-β (2 ng/ml) for 2 d in DMEM. Conditioned media proteins were then collected, concentrated, and analyzed through gelatin zymography for secreted enzymatic activity (A) (the secreted proenzymes of human MMP-2 and MMP-9 are 72 and 92 kDa, respectively) and immunoblotting for MMP-9 protein secretion (B).