Figure 4.

miR-21 effect on cell invasion of breast cancer cells induced by TGF-β1. Cell invasion was determined in MCF-7 cells by the Transwell chamber assay following transfection with anti-miR-21 and scramble anti-miR-NC alone or in combination with TGF-β1. (A) Representative images from invasion assays (magnification, ×100). (B) The average number of cells that invaded through the filter was counted. The downregulation of miR-21, using anti-miR-21, in MCF-7 cells significantly inhibited invasion induced by TGF-β1. Data are presented as the mean ± standard error of the mean of three independent assays. **P<0.01. miR, microRNA; TGF-β1, transforming growth factor β1; NC, negative control.