In our study, the alterations in epithelial and mesenchymal marker proteins by S100A4 knock-down were not observed with exogenous S100A4 treatment or with S100A4 neutralization (Fig. 4), suggesting that intracellular, not extracellular, S100A4 promotes mesenchymal transition of prostate tumor cells. This evidence concerns the gene S100A4 and prostate neoplasm.