Abstract: Objective To investigate the inhibitory effect of miR-4539 on the growth of glioma cells. Methods The expression levels of miR-4539 in glioma samples and 7 glioma cell lines were detected by RT-PCR. CCK-8 method , flow cytometry and Western blot were used to detect the role of miR-4539 in glioma cells. Dual luciflucase assay was used to verify whether Foxp1 is a direct target of miR-4539. To investigate the inhibitory effect of miR-4539 transfection on tumor growth in mice, a mouse transplanted tumor model was constructed. Results (1) The expression level of miR-4539 in glioma tissues was significantly lower than that in normal brain tissues (P<0.05). The expression level of miR-4539 in 7 commonly used human glioma cell lines (U87, U251, U373, T98G, LN18, LN229, SF295) was significantly lower than that in human normal glioma cell line HEB (P<0. 05). (2) Compared with the miR-NC group, the expression levels of miR-4539 in T98G cells and LN18 cells were significantly increased 72 h after transfection of miR-4539 (P<0. 05). CCK-8 showed that the overexpression of exogenous miR-4539 significantly inhibited the proliferation of T98G and LN18 cells. Meanwhile, T98G and LN18 cell cycle arrest was induced, and the percentage of G0 / G1 phase cells was increased, while the percentage of S phase cells was decreased, and the expression levels of cell cycle regulatory proteins cyclinD1, cyclinE1 and Ser780 were also significantly decreased (P< 0.05). ( 3) Luciferase reports showed that Foxp1 is a direct target of miR-4539 and can be directly regulated by miR-4539. At 6 weeks after T98G cells were inoculated, the average volume and weight of transplanted tumor in the miR-4539-transfected mice were significantly smaller than those in the miR-NC group (P<0.05). (4) After overexpression of miR-4539 in T98G and LN18 cells, the expression of Foxp1 mrna and protein were significantly decreased. Immunofluorescence result also confirmed that miR-4539 reduced the expression of Foxp1 in T98G and LN18 cells. Conclusions MiR-4539 acts as a tumor suppressor by targeting Foxp1, which is expected to be a new target for the diagnosis and treatment of gliomas.