TGF-β1/H₂O₂/LPS facilitates invasive capability of non-invasive breast cancer cells.

<p>(<b>A</b>) MCF-7 and T-47D cells were cultured in absence or presence of TGF-β1 (5 ng/ml)/H₂O₂ (50 µM)/LPS (100 ng/ml) for the indicated time, and then used for Matrigel invasion assay. (<b>B–D</b>) Tumor cells were cultured in absence or presence of TGF-β1, H₂O₂ and LPS for 8 days. The cells were then used for following experiments. (<b>B</b>) The cells were used for Matrigel invasion assay. (<b>C</b>) The expression of αvβ3 was analyzed by real-time RT-PCR and flow cytometry. αvβ3 expression index was calculated as described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0065906#s4" target="_blank">Materials and Methods</a>. (<b>D</b>) The cells were then cultured in presence of matrigel for 48 h. The mRNA level of <i>MMP9</i> was detected by real-time RT-PCR. The MMP-9 in supernatants was detected by zymography assay, and the fold difference of active MMP-9 was calculated after densitometric analysis of the gel. <i>P</i> values, *<i>P</i><0.05, **<i>P</i><0.01.