Expression of soluble BMP-2 and Wnt antagonists by MM cell lines. mRNA expression of antagonists for BMP-2 (A) and Wnts (B). Total RNA (2 μg) extracted from the indicated cell lines was reverse transcribed, and 1 μL of the 20-μL reaction was used in PCR analyses as described in “Patients, materials, and methods.” BMP-2 antagonists noggin, chordin, and follistatin (A) and Wnt antagonists sFRP-1, sFRP-2, sFRP-3 and DKK-1 (B) and GAPDH mRNA expression were analyzed. The MG63 osteosarcoma cell line was used as a positive control. (C) sFRP-2 protein was detected in total cell lysates extracted from the indicated cell lines (top lane) and immunoprecipitants of their CM using sFRP-2 antibody and protein A–Agarose beads (bottom lane) by Western blot analysis. β-actin was shown as a protein loading control of total cell lysates (middle lane).