Circular RNA circFGFR1 Functions as an Oncogene in Glioblastoma Cells through Sponging to hsa-miR-224-5p

Figure 3

circFGFR1 increases CXCR4 level through sponging to hsa-miR-224-5p. (a) The intersection of predicted miRNA targeting circFGFR1 and CXCR4 according to Starbase database. (b) miRNAs binding with circFGFR1 in SNB19 cells analyzed by circRIP assay. (c) The luciferase activity of pLG3-circFGFR1 in the SNB19 cells after cotransfection with miRNAs. (d) Putative binding sites of hsa-miR-224-5p with respect to circFGFR1 and CXCR4 3-URT were predicated via Starbase. (e) The luciferase activity of pLG3-circFGFR1 or pLG3-CXCR4 3-UTR in the SNB19 cells after cotransfection with hsa-miR-224-5p. (f) The RNA enrichment of circFGFR1, hsa-miR-224-5p, and CXCR4 in SNB19 cells after immunoprecipitated with anti-AGO2 antibody using RIP assay. (g) The RNA enrichment of circFGFR1, hsa-miR-224-5p, and CXCR4 in SNB19 cells using RNA pull-down assay. SNB19 cells were transfected with biotin-labeled mi-NC or hsa-miR-225-5p and pull down with streptavidin agarose beads. (h) The luciferase activity of pLG3- CXCR4 3-UTR in the SNB19 cells after cotransfecting with hsa-miR-224-5p solely or combined with pCDNA3.1-circFGFR1. (i) The expression of hsa-miR-224-5p in SNB19 cells stable overexpressing Vehicle, circFGFR1, sh-NC, and sh-circFGFR1, respectively, using qPCR. (j) The expression of circFGFR1 in SNB19 cells transfected with mi-NC, hsa-miR-224-5p, inhibitor NC, and inhibitor, respectively, using qPCR. The data are presented as the , experiments in (b–j), , , .

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