Circular RNA circEPSTI1 accelerates cervical cancer progression via miR-375/409-3P/515-5p-SLC7A11 axis

Background: Circular RNAs (circRNAs) is one kind of non-coding RNAs (ncRNAs) and exert crucial functions in biological processes and intracellular gene expression modulation. However, the biological roles and expression status of the majority of circRNAs still remain unknown in cervical cancer. Results: In this study, circEPSTI1 (hsa_circRNA_000479) was significantly upregulated in cervical cancer. We first discovered the impact of circRNA on cell ferroptosis in cervical cancer. Interestingly, circEPSTI1 attenuates the effect of ferritin which is mediated by SLC7A11 based on lipid peroxidation measurements and reduced glutathione and glutathione (GSH/GSSG) assay. Conclusions: circEPSTI1-miR-375/409-3P/515-5p-SLC7A11 axis affected the proliferation of cervical cancer via the competing endogenous RNAs (ceRNA) mechanism and was relative to ferroptosis. Our findings provided experimental evidences which revealed that circEPSTI1 might act as a new and useful biomarker for monitoring and treatment target for cervical cancer. Methods: The expression of circEPSTI1 was examined in cervical cancer cells. Then, we observed the impact of circEPSTI1 expression on the proliferation of cervical cancer by loss-of-function assays both in vivo and vitro. RIP and luciferase reporter assay revealed that circEPSTI1 sponges miR-375, miR-409-3p and miR-515-5p to upregulate SLC7A11 expression. We applied mouse xenograft experiments in mice to validate our results.