PTBP1 and osteosarcoma: In order to determine the roles of ELK1/miR-134/PTBP1 in chemoresistance of osteosarcoma cells after aerobic glycolysis, we detected the consumption of glucose and lactic acid, and the ratio of ATP production in DXR-resistant cells (U2OS/DXR) in the presence or absence of ELK1 and/or miR-134 or miR-134.