RETRACTED: MicroRNA-200b inhibits the growth and metastasis of glioma cells via targeting ZEB2 (Retracted article. See vol. 59, 2021)

MicroRNAs (miRs) have been found to play important roles in mediating a variety of biological processes in human cancers, including tumor cell proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT). In the present study, we aimed to investigate the putative role of miR-200b in the progression of glioma. Real-time RT-PCR data showed that the miR-200b levels were frequently reduced in primary glioma tissues (n=88) and cell lines, when compared to normal brain tissues (n=25). Moreover, decreased miR-200b level was tightly associated with the malignant progression of glioma. Overexpression of miR-200b significantly suppressed cell proliferation, migration, invasion and EMT in glioma U251 and U87 cells. Luciferase reporter assay data further identified ZEB2 as a direct target of miR-200b, and the protein expression of ZEB2 was markedly reduced after overexpression of miR-200b in U251 and U87 cells. Furthermore, restoration of ZEB2 effectively reversed the reduced expression of ZEB2, as well as the suppressive effects of miR-200b overexpression on the proliferation, migration, invasion and EMT in glioma U251 and U87 cells. Moreover, in vivo study showed that overexpression of miR-200b significantly inhibited tumorigenesis as well as the tumor growth of glioma cells, and effectively protected nude mice from tumor-induced death. Taken together these findings suggest that miR-200b has suppressive effects on the proliferation, migration, invasion and EMT of glioma cells, partly at least, via targeting ZEB2. Therefore, miR-200b acts as a novel tumor suppressor in glioma, and thus may become a promising therapeutic candidate for glioma.