PVT1 and osteosarcoma: HK2 was a direct target of miR-497, long non-coding RNA PVT1 acts as molecular sponge to repress miR-497, as a result, PVT1 promotes glycolysis and cell proliferation in osteosarcoma and form a PVT1/miR-497 axis in the Warburg effect through regulation of HK2 expression [39] (Fig. 1).