MEG3 inhibits proliferation and invasion and promotes apoptosis of human osteosarcoma cells

Osteosarcoma is known as a malignant tumour with a high mortality rate in orthopaedic settings; however, the factors associated with its degree of malignancy and the biological response remains to be elucidated. Although the essential role of the long noncoding RNA (lncRNA) maternally expressed 3 (MEG3) has been recently reported, its biological functions and regulatory mechanism in osteosarcoma cells have not yet been reported. In the present study, reverse transcription-quantitative polymerase chain reaction analysis revealed that the expression of MEG3 in MG63 cells was lower compared with in hFOB1.19 cells. Furthermore, it was observed that overexpressing MEG3 in MG63 cells resulted in a decline in the proliferation and invasion, and a marked increase in apoptosis. Additionally, western blotting was used to detect the changes in expression of p53 and MDM2 proto-oncogene, which may be regulated by MEG3, and proteins that associated with cell proliferation, invasion and apoptosis. It was demonstrated that the upregulation of MEG3 significantly increased the transactivation of p53 and induced downstream changes in protein expression. In conclusion, these experiments have demonstrated that MEG3 serves an essential regulatory role in the biological processes of human osteosarcoma cells, and imply that MEG3 may be a marker for predicting the occurrence and development of osteosarcoma.