RESUMEN
Circular RNA (circRNA) has been confirmed to regulate breast cancer (BC) progression. However, the role of circ_0059457 in BC progression is still unclear.The expression of circ_0059457, taspase 1 (TASP1), microRNA (miR)-140-3p and ubiquitin-binding enzyme E2C (UBE2C) was detected by quantitative real-time PCR. Cell proliferation, migration, invasion and sphere formation ability were assessed by cell counting kit-8 assay, EdU assay, wound healing assay, transwell assay and sphere formation assay. Cell glycolysis was assessed by detecting glucose uptake, lactate levels and ATP/ADP ratio. Dual-luciferase reporter assay, RIP assay, RNA pull-down assay were used to validate RNA interaction. Xenograft tumor model to assess the effect of circ_0059457 on BC tumor growth in vivo. Circ_0059457 had elevated expression in BC tissues and cells. Circ_0059457 knockdown inhibited BC cell proliferation, metastasis, sphere formation ability, and glycolysis. In terms of mechanism, circ_0059457 sponged miR-140-3p, and miR-140-3p targeted UBE2C. MiR-140-3p inhibition reversed the effect of circ_0059457 knockdown on BC cell malignant behaviors. Besides, miR-140-3p overexpression inhibited BC cell proliferation, metastasis, sphere formation ability and glycolysis, and these effects were abrogated by UBE2C enhancement. Furthermore, circ_0059457 regulated UBE2C expression through sponging miR-140-3p. Additionally, circ_0059457 knockdown obviously inhibited BC tumor growth in vivo. Circ_0059457 promoted BC progression via miR-140-3p/UBE2C axis, which provided potential target for the treatment of BC.