Fig. 5

c-Jun is involved in amphiregulin (AREG)-induced cellular communication network factor 2 (CCN2) and fibronectin expressions in A549 human epithelial cells. A A549 cells were incubated with AREG (10 ng/ml) for 0 ~ 120 min. Levels of phospho-c-Jun Ser63, and c-Jun were immunodetected with specific antibodies and assessed using Western blotting. The results are expressed as the mean ± SEM, *p < 0.05, n = 3, compared to the control group. B Cells were pretreated with curcumin for 30 min and then stimulated with AREG (10 ng/ml) for another 6 h. Western blotting was performed to assess the levels of cellular communication network factor 2 (CCN2) and α-tubulin in cell lysates, Data are shown as the mean ± SEM, n = 3. *p < 0.05, relative to AREG-stimulated cells. C Schematic diagram of activator protein (AP)-1 binding to the CCN2 promoter. A549 cells were exposed to AREG (10 ng/ml) for 30 min. The AP-1-binding site of the CCN2 promoter region was identified through a ChIP assay. Typical traces are presented in all three experiments