Fig. 4

SMAD signaling mediates the stimulatory effects of GDF-8 on Snail and Slug expression. A HTR-8/SVneo cells were pretreated with vehicle control (DMSO) or 10 µM SB431542 for 1 h, and then treated with 30 ng/mL GDF-8 for 12 h. The protein levels of Snail and Slug were examined by western blot. B HTR-8/SVneo cells were transfected with 50 nM control siRNA (si-Ctrl) or SMAD4 siRNA (si-SMAD4) for 48 h, and then treated with 30 ng/mL GDF-8 for 12 h. The protein levels of Snail, Slug, and SMAD4 were examined by western blot. The results are expressed as the mean ± SEM of at least three independent experiments. Multiple comparisons were analyzed using one-way ANOVA followed by Tukey’s multiple comparison test. Values that are statistically different from one another (p < 0.05) are indicated by different letters. The values with any common letter are not significantly different