Figure 5

Plasminogen-urokinase plasminogen activator receptor signaling rapidly upregulates interleukin-like epithelial-to-mesenchymal transition inducer secretion by mobilizing its intracellular protein pool. (A) to (D) Western blot analysis of interleukin-like epithelial-to-mesenchymal transition inducer (ILEI) in whole-cell lysates and conditioned medium (CM) of EpRas cells not treated or treated with plasmin for 16 hours after serum withdrawal (A), harvested 24 hours after serum withdrawal and incubation with plasmin for the indicated periods of time (B), treated with indicated concentrations of plasmin, thrombin or plasma kallikrein for 24 hours after serum withdrawal (C) and treated with indicated concentrations of neutrophil elastase (NE) for 24 hours after serum withdrawal (D). (E) Fold change ± SEM in ILEI secretion of EpRas cells after plasmin, thrombin, plasma kallikrein and NE treatments calculated by semiquantification of Western blots of three independent experiments. (F) and (G) Western blot analysis of ILEI in whole-cell lysates and CM of EpRas cells treated with indicated concentrations of plasmin, tissue plasminogen activator (tPA) or urokinase plasminogen activator (uPA) for 24 hours after serum withdrawal (F) and in control and urokinase plasminogen activator receptor (uPAR) short-hairpin RNA EpRas cells not treated or treated with plasmin or transforming growth factor β-1 (TGFβ-1) for 24 hours after serum withdrawal (G).