Figure 1

The MAPK pathway regulates amphiregulin induction and amphiregulin release upon HGF stimulation depends on amphiregulin protein synthesis. (A) Quantification of amphiregulin protein release in different SCC cell lines treated with HGF for 24 h. Ligand release was assayed using sandwich ELISA. Error bars indicate SEM of three independent experiments. (B) Quantification of amphiregulin mRNA induction. SCC9 cells were treated with 100 ng/ml HGF for the indicated time points. Data represent the increase of amphiregulin normalized to HPRT1 cDNA. Values are shown as mean ± SD (n = 2). (C) Quantification of amphiregulin protein release. Values are shown as mean ± SD (n = 2). (D) Quantification of amphiregulin protein release. SCC9 cells were treated with 100 ng/ml HGF and with the translation inhibitors cycloheximide (=CHX; 1 μg/ml) and geneticin (=G418; 1 mg/ml) for 24 h. Ligand release into the supernatant was assayed using sandwich ELISA. Error bars indicate SEM of three independent experiments. (E) Quantification of amphiregulin mRNA induction. SCC9 cells were pretreated with 5 μM of the MEK inhibitor UO126 and 50 nM of the PI3K inhibitor wortmannin (=W) for 15 min before 2 h HGF treatment. (F) Quantification of amphiregulin protein release. SCC9 cells were pretreated for 15 min with UO126 and wortmannin before 24 h HGF treatment. Error bars indicate SEM of three independent experiments. Asterisks indicate statistically significant repression or induction (p < 0.05, paired t-test).