MicroRNA-218 promotes osteosarcoma cell apoptosis by down-regulating oncogene B lymphoma mouse Moloney leukemia virus insertion region 1
LAI Guihua
HUANG Ailan
ZHAO Zhi
LU Xinghao
ZU Wenxuan
Abstract：Objective To investigate the tumor-suppressing effect of microRNA-218(miR-218)in osteosarcoma(OS)and explore its molecular mechanism.Methods We examined the expression levels of miR-218 in 68 pairs of OS and adjacent tissue samples using qRT-PCR.Cultured human OS cell line Saos-2 was transfected with miR-218 mimics or anti-miR-218 mimics,and the cell apoptosis was assessed using CCK-8 assay,annexin V-FITC staining and Western blotting.We also analyzed the potential functional targets of miR-218 in Saos-2 cells using luciferase assay,qRT-PCR and Western blotting.Results The expression level of miR-218 was lowered by at least 8 folds in OS tissues as compared with the adjacent tissues.In cultured Saos-2 cells,transfection with miR-218 mimics for 24,36,and 48 h resulted in a significant reduction in the cell viability,while transfection with anti-miR-218 mimics significantly increased the cell viability.The cells transfected with miR-218 mimics showed an obviously enhanced expression of cleaved poly (ADP-ribose)polymerase(C-PARP)as compared with the cells transfected with anti-miR-218 mimics and the control cells.Flow cytometry demonstrated obviously increased apoptosis of the cells following miR-218 mimics transfection. We identified the oncogene B lymphoma mouse Moloney leukemia virus insertion region 1(BMI-1)as a specific target of miR-218 in Saos-2 cells. BMI-1 expressions at both the mRNA and protein levels were significantly reduced in Saos-2 cells overexpressing miR-218 but increased in the cells with miR-218 knockdown as compared to the control cells.Luciferase reporter assay indicated that miR-218 directly inhibited the expression of BMI-1 via binding to its 3'-UTR in OS cells.Conclusion miR-218 can promote OS cell apoptosis and plays the role as a tumor suppressor by down-regulating BMI-1.
Keywords：miR-218oncogene B lymphoma mouse Moloney leukemia virus insertion region 1osteosaromaapoptosis
Publication Date：2018-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：6( 505-510 )