Detection of relaxin-2 mRNA and proterin expression in human osteosarcoma cell lines. A. Gel images of electrophoresis. B. Western blot assay. MG-63 cell line had the highest expression level of relaxin-2 mRNA and protein. Osteosarcoma tissues showed obviously higher relaxin-2 mRNA expression than corresponding non-tumor tissues. β-actin was used to normalize for any differences in mRNA between lanes.