Figure 4

Suppression of migration and invasion and pro-matrix MMP-9/MMP-2 activation in MDA-MB-231 cells by BER. MDA-MB-231 cell migration (A) was examined in the presence of BER at the indicated concentrations for 6 h in upper chamber of the fibronectin-coated transwell chamber (serum-free). The right panels show the propidium iodide-stained MDA-MB-231 cells migrating through fibronectin-coated transwell chamber. The cells were treated 6 h with the 0 (A1: vehicle as the control) and 20 μM BER (A2). In the (B), MDA-MB-231 cell invasion was examined in the presence of BER at the indicated concentrations for 16 h in upper chamber of the Matrigel-coated transwell chamber (serum-free). The right panels show the propidium iodide-stained MDA-MB-231 cells invading through Matrigel-coated transwell chamber. The cells were treated 16 h with the 0 (B1: vehicle as the control) and 20 μM BER (B2). Relative migration (%) ± SD (Bar) and relative invasion (%) ± SD are shown for the indicated BER concentrations and the 0 (vehicle) is the control. (C) Inhibition of pro-matrix MMP-9/MMP-2 activation in supernatants of invading MDA-MB-231 cells by BER. MDA-MB-231 cells were cultured for 16 h in upper chamber of the Matrigel-coated transwell chamber (serum-free) in the presence of BER at 0, 1 μM, 10 μM, and 20 μM, respectively. The activation (M r 72,000 and M r 92,000 gelatinase activities) of MMP-9/MMP-2 zymogens (z-MMP-9/z-MMP-2) in the supernatants of invading MDA-MB-231 cells mentioned in (B) was determined by gelatin zymography analysis. Values (the relative activation of MMP-9/MMP-2 zymogens) are shown as mean ± SD of 3 runs (n = 3) for each sample, only one set of gels is shown. The figures (A, B and C) are the representative of 3 similar experiments performed. Statistical analysis was done using the ANOVA and Bonferroni test. *: P < 0.05, **, P < 0.01 (n = 6).