Fig. 2

Knockdown of circGNB1 suppressed the malignant phenotype of GSCs in vitro. a QRT-PCR assays showed the expression of circGNB1 in different GBM and GSC cell lines. b QRT-PCR assays were performed to detect the expression of circGNB1 after knockdown or overexpression treatment by using the lentiviral vector. c–f MTS assays showed that the cell viabilities of GSC27 and U87 were significantly decreased after circGNB1 knockdown, while the opposite results could be obtained following circGNB1 overexpression treatment in GSC23 and U251. g, h Cell proliferation analysis by Edu assays showed that circGNB1 knockdown could reduce the positive rates of GSC27 and U87, whereas circGNB1 overexpression could promote the proliferation of GSC23 and U251. Scale bar = 100 µm. i, j Transwell assays were performed to detect cell invasion capability using GSC27 and U87 with circGNB1 knockdown or using GSC23 and U251 with circGNB1 overexpression. Scale bar = 50 µm. k, l The self-renewing abilities of GSCs were measured by neurosphere formation assays with circGNB1 knockdown or circGNB1 overexpression treatment. Scale bar = 20 µm. m–p Limiting dilution assays showed circGNB1 knockdown or overexpression affected the neurosphere-forming capacity of GSCs. Data represent mean ± SD (three independent experiments). *p < 0.05; **p < 0.01; ***p < 0.001