miR-4530 inhibits the malignant biological behaviors of human glioma cells by directly targeting RTEL1

Human glioma is the most common primary brain tumor and is associated with high morbidity and mortality. Aberrant expressions of microRNAs (miRNAs) are involved in glioma progression. In the present study, we aimed to elucidate the roles of miR-4530 in the pathogenesis of gliomas. miR-4530 expression was examined in human glioma clinical tissues and cell lines including U251 and T98G. The target gene of miR-4530, RTEL1, was predicted with online tools and validated by luciferase reporter assay. Lentivirus infection, transfection of plasmids, and miRNA mimics were used to manipulate gene expression. Cell proliferation was determined using the CCK-8 method, and migration and invasion assays were determined with transwell experiments. Colony formation was measured by crystal violet staining, while apoptosis was determined by Annexin V/PI staining. The anti-tumor effects of miR-4530 were evaluated in nude mice xenografted using U251 cells. Our results showed that miR-4530 was significantly down-regulated in human glioma tissues and cell lines. miR-4530 over-expression inhibited the malignant behaviors of U251 and T98G cells, including reduced proliferation, diminished colony formation, migration and invasion, and increased apoptosis. Further mechanistic investigations revealed that RTEL1 is a direct functional target of miR-4530 in gliomas, and its over-expression remarkably reverses the effects of miR-4530 mimics on inhibiting these malignant behaviors. In addition, miR-4530 over-expression inhibited the growth of xenografted U251 glioma in nude mice. Therefore, miR-4530 acts as a tumor-suppressor gene and inhibits the malignant biological behaviors of human glioma cells, which is associated with directly targeting RTEL1. The miR-4530/RTEL1 axis is a potential therapeutic target for gliomas.