SOX7 inhibits tumor progression of glioblastoma and is regulated by miRNA-24

OBJECTIVE: Sex-determining region Y-box 7 (SOX7) is a putative tumor suppressor in various types of human cancers. In the present study, the expression and function of SOX7 was investigated in human glioblastoma (GBM) cells. METHODS: Real-time PCR and western blot were carried out to reveal the expression of SOX7 in GBM specimens and cultured cell lines. A short interfering RNA (siRNA) targeting SOX7 was synthesized and transfected into U87 cells. 3-(4,5-Dimethylthiazol-2-yl)- 2,5-diphenyltetrazolium bromide (MTT) assay was performed to valuate the cell proliferation ability in U87 cells. Bioinformatics analysis further predicted its regulation by microRNA-24 (miR-24). Luciferase reporter assay was performed to prove this regulation. RESULTS: SOX7 was downregulated in GBM specimens and cell lines. Inhibition of SOX7 in cultured U87 cells resulted in a slower growth rate. Mechanically, SOX7 was a target of miR-24, demonstrated by reporter assay. CONCLUSION: SOX7 was a strong tumor suppressor regulated by miR-24 in human GBM cells.