LncRNA SOX2‐OT is a novel prognostic biomarker for osteosarcoma patients and regulates osteosarcoma cells proliferation and motility through modulating SOX2

Long noncoding RNA (LncRNA) SOX2 overlapping transcript (SOX2‐OT) has been shown to serve an oncogenic role in human lung cancer, hepatocellular carcinoma, and gastric cancer. However, the clinical significance and biological function of lncRNA SOX2‐OT in osteosarcoma are still unclear. LncRNA SOX2‐OT expression was measured in osteosarcoma tissues and cell lines. Loss‐of‐function and gain‐of‐function studies were performed to observe the effects of lncRNA SOX2‐OT on osteosarcoma cells proliferation, migration, invasion, and expressions of cancer stem cell biomarker. The relationship between lncRNA SOX2‐OT and SOX2 was analyzed in osteosarcoma tissues and cells. Rescued‐function studies were conducted to confirm the role of SOX2 in the regulation of lncRNA SOX2‐OT in osteosarcoma cells migration, invasion, and expression of cancer stem cell biomarkers. In our results, lncRNA SOX2‐OT expression was increased in osteosarcoma tissues and cell lines, and associated with malignant status and overall survival in osteosarcoma patients. LncRNA SOX2‐OT regulated osteosarcoma cells proliferation, migration, invasion, and expression of cancer stem cell biomarkers. LncRNA SOX2‐OT positively regulated SOX2 expression in osteosarcoma cells and positively associated with SOX2 expression in osteosarcoma tissues. The rescued‐function studies suggested that SOX2 is necessary for lncRNA SOX2‐OT induced osteosarcoma cells migration, invasion, and expression of cancer stem cell biomarkers. In conclusion, lncRNA SOX2‐OT is a prognostic biomarker for osteosarcoma patients and serves an oncogenic role to regulate osteosarcoma cells migration, invasion, and expression of cancer stem cell biomarkers. © 2017 IUBMB Life, 69(11):867–876, 2017