MicroRNA-643 regulates the expression of ZEB1 and inhibits tumorigenesis in osteosarcoma

Osteosarcoma is among the most malignant types of tumor worldwide and has become a leading contributor to tumor incidence, particularly in adolescents. Resistance to conventional treatment and the complexity of osteosarcoma tumorigenesis has resulted in high mortality rates. MicroRNAs are a class of noncoding RNAs, which regulate numerous biological processes. However, the involvement of miR-643 in osteosarcoma remains to be elucidated. In the present study, reverse transcription-quantitative polymerase chain reaction, luciferase reporter assay, invasion assay, viability assay, western blot analysis and in vivo implantation were performed to analyze the action of miR-643 in osteosarcoma. The results demonstrated that miR-643 inhibited the progression of osteosarcoma and acted as a potential tumor suppressor. The expression of miR-643 was downregulated in osteosarcoma tissues and cell lines. In addition, miR-643 transfection significantly impaired the proliferation and invasion of osteosarcoma cells. The present study also identified Zinc finger E-box-binding homeobox 1 (ZEB1) as a direct target of miR-643, and the ectopic expression of ZEB1 counteracted the effect of miR-643 transfection. A significant inverse correlation was also found between the expression of miR-643 and ZEB1. A low expression of miR-643 or a high expression of ZEB1 was associated with poor patient survival rates. The results of the present study suggested that the decreased expression of miR-643 may be involved in the mechanism underlying the development of osteosarcoma. The intricate interactions between miR-643 and ZEB1 may serve as a potential therapeutic target in osteosarcoma oncogenesis.