FOXO1 and osteosarcoma: FOXO1 participated in modulating of many biological processes, such as apoptosis, DNA damage repair, cell cycle arrest and/or oxidative stress resistance,23 and decreased FOXO1 mRNA levels were detected in breast carcinoma, prostate cancer, osteosarcoma, hepatocellular carcinoma and Ewing sarcoma.24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38