EXPRESSION OF MIR-98 IN GLIOMA AND THE PROMOTION EFFECT ON THE INVASION OF GLIO- MA CELLS BY MIR-98 DOWNREGULATION

Zheng Bo1, Mao hua1, Wu Zhi2, Tao Chen1*

1Department of Neurosurgery, Jingzhou Central Hospital, Jingzhou, 430020 Hubei, China - 2Department of Neurosurgery, First Hospital of Lanzhou Lanzhou 730000, China

 Objective: To detect the expression of miR-98 in glioma tissues and to investigate the effect of miR-98 on the invasion and mi- gration of the human glioma cell line U251.

Methods: The expressions of miR-98 in glioma tissues and in normal brain tissues were detected by real-time fluorescent quan- titative PCR. After cotransfection with the miR-98 inhibitor and the wild-type inhibitor of nuclear factor kappa B kinase epsilon (IKB- KE) 3’-untranslated region (UTR) or the mutation type IKBKE 3’-UTR recombination vector, the specific binding ability of miR-98 to 3’-UTR in the IKBKE gene was examined by the luciferase gene reporter system. The expression levels of miR-98, IKBKE mRNA and IKBKE protein in glioma cell line U251 after transfection with the miR-98 inhibitor were measured by real-time fluorescent quantita- tive PCR and Western blotting, respectively. The abilities of migration and the invasion of U251 cells after transfection with the miR-98 inhibitor were detected by Transwell assay. The expression of miR-98 in U251 cells after transfection with IKBKE siRNA was detected by real-time fluorescent quantitative PCR.

Results: The expression of miR-98 in glioma tissues was lower than that in normal brain tissues (P < 0.05). The fluorescence intensity of U251 cells cotransfected with the miR-98 inhibitor and wild-type IKBKE recombination vector was improved (P < 0.05). The expression of miR-98 was downregulated, and the expression levels of IKBKE mRNA and protein were upregulated in U251 cells after transfection with the miR-98 inhibitor (all P < 0.05). While the abilities of migration and the invasion of U251 cells after trans- fection with the miR-98 inhibitor were increased (both P < 0.05), there was no change in the expression of miR-98 in U251 cells after inhibition of the IKBKE expression (P > 0.05).

Conclusions: The expression of miR-98 is low in glioma tissues. The miR-98 inhibitor may promote the invasion and migration of glioma U251 cells by regulation of the IKBKE expression.