Overexpression of circASPM promoted the proliferation of GSCs in vitro. a, b: The expression of circASPM in GSC11 and GSC12 after transfection of the circASPM overexpression plasmids as measured by qPCR. c, f: circASPM overexpression significantly increased the proliferation of GSC11 and GSC12 in MTS assays. d, e, f: Proliferative capacity of tumor cells was inhibited after circASPM overexpression as measured by Edu assays. Scale bar = 50μm. g, h, i, j: Representative images of neurospheres and extreme limiting dilution assays showed tumor formation rate up-regulated after circASPM overexpression in GSC11 and GSC12. Scale bar = 50μm. All data are shown as the mean ± SD (three independent experiments). *P < 0.05; **P < 0.01; ***P < 0.001.