Thrombin Promotes Matrix Metalloproteinase-13 Expression through the PKCδ/c-Src/EGFR/PI3K/Akt/AP-1 Signaling Pathway in Human Chondrocytes
Figure 4
Thrombin-mediated EGFR transactivation in human chondrocytes. ((a) and (b)) qPCR and ELISA analyses of MMP-13 expression in chondrocytes, which were pretreated with AG1478 (1 μM) for 30 min or transfected with EGFR siRNA for 24 h and then stimulated with thrombin for 24 h. (c) Western blotting analyses of EGFR phosphorylation in cells incubated with thrombin for the indicated time intervals. (d) Western blotting analyses of EGFR phosphorylation in chondrocytes pretreated with rottlerin or PP2 for 30 min and then stimulated with thrombin for 60 min. * as compared with basal levels. # as compared with the levels in the thrombin-treated group.
