Benping Zhang, Ling Ma, Jia Wei, Jingyu Hu, Zichu Zhao, Youping Wang, Yan Chen and Fei ZhaoPages 807-817 (11)
Methods: In this study, the target gene and the potential effect of miR-137 in MM were investigated.
Results: The results showed significantly down regulated expression of miR-137 in MM cell lines and in the CD138+ bone marrow mononuclear cells of MM patients. A dual luciferase reporter gene analysis revealed that MITF is a direct target of miR-137. The overexpression of miR-137 or transfection of MITF-shRNA had no significant effect on the expression of serine/ threonine protein kinase (AKT), but the expression of MITF, c-MET, p-AKT, and its phosphorylated substrate protein decreased significantly, which was accompanied by an increase in p53 expression. In addition, the overexpression of miR-137 or MITF-shRNA significantly improved the 36-hour inhibition rate and apoptosis rate in multiple myeloma cells treated with dexamethasone. The overexpression of MITF could counteract the biological effect of miR-137 in multiple myeloma cells.
Conclusion: We conclude that MITF is a direct target of miR-137. The miR-137 can improve the dexamethasone sensitivity in multiple myeloma cells by reducing the c-MET expression and further decreasing the AKT phosphorylation via targeting MITF.
AKT, c-MET, dexamethasone sensitivity, miR-137, MITF, multiple myeloma, phosphorylation.
Department of Hematology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China.