MACC1 is highly expressed in human osteosarcoma (OS) tissues and cell lines and its expression correlates with prognosis in OS patients. (A) Quantitative PCR assays were conducted to measure the MACC1 mRNA levels in OS tissues and the corresponding adjacent noncancerous tissues ( n = 30). (B) Immunoblot assays were conducted to detect the protein levels of MACC1 in OS tumor tissues and the corresponding adjacent noncancerous tissues. (C) Immunoblot assays were conducted to measure the protein levels of MACC1 in the U-2OS, MG-63, Saos-2, and HOS osteosarcoma cell lines, and normal human umbilical vein endothelial cells (HUVECs). (D) Immunohistochemistry was performed to measure the protein levels of MACC1 in human OS tissues and the corresponding adjacent noncancerous tissues; representative images are shown (×100 and ×400 magnification, respectively). (E) Kaplan–Meyer survival analysis showed the correlation between MACC1 expression in tumor tissues and overall survival or disease-free survival rates.