The Potential Tumor Promotional Role of circVAPA in Retinoblastoma via Regulating miR-615-3p and SMARCE1

BACKGROUND: Growing evidence reveals that circular RNAs (circRNAs) play roles in cancer development. However, the effects and possible mechanisms of circRNAs in retinoblastoma (RB) are far from clear. METHODS: circVAPA expression pattern was identified by RT-qPCR. circVAPA induced effects on RB cells were tested by CCK-8, clone forming, flow cytometry and transwell assays. Bioinformatics assay, rescue experiments and dual-luciferase tests were applied for mechanism exploration. Additionally, mouse models were established for in vivo assays. RESULTS: circVAPA was upregulated in human RB specimen and RB cell lines, and was correlated with poor outcomes of Rb patients. Knockdown of circVAPA could suppress the malignant phenotypes of RB. Mechanistic experiments demonstrated that miR-615-3p could reverse the circVAPA induced effects on RB cells, and the downstream oncogene SMARCE1 was positively regulated by circVAPA via miR-615-3p. Further, in vivo analysis confirmed the findings. CONCLUSION: In summary, circVAPA promoted RB proliferation and metastasis by sponging miR-615-3p, thereby upregulating SMARCE1. CircVAPA was a potential biomarker for Rb therapy.