FIGURE 4.

TAOB-CMs and BMP-2 increase the activation of MAPK and elevate the expression of Runx2 and Snail. A and B, TAOB-CMs (A) and BMP-2 (B) increase the phosphorylation of SMAD, ERK, and p38. C and D, TAOB-CMs (C) and BMP-2 (D) enhance the expression of Runx2 and Snail protein. Cells were treated with OB-CM (20%), TAOB-CMs (20%), or BMP-2 (20 ng/ml) for the indicated times. The expressions of various proteins were determined by immunoblot assay. E, TAOB-CMs and BMP-2 enhance the expression of Runx2 and Snail mRNA. The cells were treated with OB-CM (20%), TAOB-CMs (20%), or BMP-2 (20 ng/ml) for a specific time (3 h for snail and 12 h for E-cadherin). The expressions of mRNA were determined by quantitative PCR. F, noggin decreases TAOB-CM-mediated MAPK activation and Runx2 and Snail up-regulation. The cells were treated with OB-CM (20%), TAOB-CMs (20%), or BMP-2 (20 ng/ml) for the indicated times. The expressions of mRNA and various proteins were determined by quantitative PCR and immunoblot assay. For F, A549 and CL1–0 cells were pretreated with or without noggin for 1 h and then treated with BMP-2 (20 ng/ml) for 6 h. The expression of various proteins was then assessed by immunoblot assay. The data shown are representative of three independent experiments. Each value is the mean ± S.D. of three independent experiments. The asterisk indicates a significant difference between control and test groups, as analyzed by Dunnett's test (p < 0.05).