tative images of an experiment that was repeated four times show equivalent expression of exogenous SnoN in different stable NMuMG cells. Aii) Transfected cells, as determined by GFP expression shown in Ai, were subjected to quantitative analysis of the intensity of the SnoN immunofluorescence signal (see Materials and Methods S1 for details). Each column in the graph represents the mean (6 SEM, n = 4 independent experiments) of the average exogenous SnoN intensity per cell of a stable transfectant expressed relative to its respective empty expression vector control. Found at: doi:10.1371/journal.pone.0013971.s005 (14.20 MB TIF) References 1. Thiery JP, Acloque H, Huang RY, Nieto MA (2009) Epithelial-mesenchymal transitions in development and disease. Cell 139: 871–890. 2. Thiery JP (2002) Epithelial-mesenchymal transitions in tumour progression. Nat Rev Cancer 2: 442–454. 3. Thiery JP (2003) Epithelial-mesenchymal transitions in development and pathologies. 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