Figure 3.

NRF3 is required to suppress breast cancer cell invasion related to EMT and MMPs. (A and B) Cell invasion assays were performed to detect the invasion potential of SKBR3 and MDA-MB-231 cells with NRF3-overexpressed plasmids or empty vector by transwell coated with matrigel. Representative images at 40× (left panel), total view for whole well (right panel) and the quantification for cell number invaded per view (B). Error bar indicated SD (**P<0.01). (C) Western blot was performed to detect the expression of E-cadherin, N-cadherin, and Vimentin protein levels in MDA-MB-231 cells over-expressed with NRF3 or not (left panel). β-actin was as a loading control. The quantification for NRF3 (pink), Viamentin (green), N-cadherin (blue), and E-cadherin (red) protein levels according to western blotting. pcDNA3.1 was used as negative control. Error bar indicated SD (**P<0.01). (D) Western blot was performed to detect the expression of MMP-2, MMP-9, TIMP-1, and TIMP-2 protein levels in MDA-MB-231 cells overexpressed with NRF3 or not (left panel). β-actin was used as loading control. The quantification for MMP-2 (pink), MMP-9 (green), TIMP-1 (blue), and TIMP-2 (red) protein levels according to western blotting. pcDNA3.1 as a negative control. Error bar indicated SD (*P<0.05 and **P<0.01). Three independent experiments were performed for all assays.

Abbreviations: NRF3, Nuclear Factor, Erythroid 2 Like 3; EMT, epithelial–mesenchymal transition; MMP, matrix metallopeptidase; TIMP, TIMP metallopeptidase inhibitor.