Fig. 4
Knockdown of circRYK reverses TGF-β1-induced epithelial-mesenchymal transition and GSC maintenance. (A) Transwell assays showed that the promoting effect of TGF-β1 treatment was reversed by knockdown of circRYK in GBM cells. (B) A three-dimensional spheroid test demonstrated that reducing the expression of circRYK in U87-GFP and pGBM-1-GFP cells counteracted the enhancing effect of TGF-β1 treatment. (C) A wound healing assay was conducted to verify the effect of simultaneous circRYK knockdown and treatment with TGF-β1 on GBM cell migration. (D) Western blotting was employed to evaluate the expression of related markers after simultaneous knockdown of circRYK and TGF-β1 treatment in GBM cells. (E) Bioluminescence imaging was used to track the effect of shcircRYK transfection and TGF-β1 treatment on intracranial tumour size. (F-I) Clonogenicity and CellTiter-Glo assays demonstrated that knockdown of circRYK reversed the effects of GSC maintenance after TGF-β1 treatment. (J) Western blotting was employed to demonstrate that knockdown of circRYK inhibited the increase in the expression of related proteins after TGF-β1 treatment. Scale bar, 100 μm. Each experiment was performed thrice, and the results are displayed as the mean ± SD. NC, negative control (**P < 0.01, ***P < 0.001)