Figure 8.

ERK5 has more targets other than FAK to regulate EMT in lung cancer cells. (A) GeneGO pathway showing changes in expression of proteins involved in EMT process. The various proteins on the right map (higher definition image is shown in Supplementary file 2: Fig. S20) are represented by different symbols (representing the functional class of the protein). Thermometers with blue or red shading next to symbols depict proteins identified in the present study: blue color represents the proteins that were downregulated in ERK5-overexpression A549 cells relative to control A549 cells; red color represents the proteins that were upregulated. (B) Knockdown of ERK5 altered the expression of EMT-related genes in A549 cells treated with or without TGF-β1, which was examined by western blotting analysis. (C) Quantitative RT-PCR analysis of epithelial and mesenchymal markers. A549 cells were treated as described in (B). (D) A549 cells co-transfected with E-cadherin promoter reporter plasmid (E-cadherin-Luc) and control siRNA (siCTRL) or ERK5 siRNA (siERK5) were incubated with or without TGF-β1 (5 ng/mL) for 24 h. Luciferase activities were normalized on the basis of β-galactosidase expression to adjust for variation in transfection efficiency. (E and F) The mRNA level of MMP2 was obviously reduced upon siERK5 treatment in A549 (E) and H1299 (F) cells. Relative mRNA levels of genes were normalized to β-actin and siCTRL was set as 1.0. Histograms in this figure are shown as means ± SD. **P < 0.01, ***P < 0.001