CircMMP11 acts as a ce-circRNA in breast cancer progression by regulating miR-1204

Background: Numerous studies have found that circular RNAs (circRNA) can serve as competing endogenous RNA (ceRNA) in cancer progression while the expression profiles and functions of competitive endogenous circRNAs (ce-circRNAs) in breast cancer (BC) have not been determined.

Methods: Six pairs of tissue samples were selected to perform ceRNA microarray, and The Cancer Genome Atlas (TCGA) data was also included to explore the ce-circRNA profiling of BC. The expression of one of the top upregulated circRNAs, circMMP11, was confirmed by qRT-PCR in both breast cancer cell lines and tissues. We also analyzed the clinical impact of circMMP11 on BC. To explore the functions of circMMP11 in BC, experiments referring to cell proliferation and migration were performed. The regulatory effect of circMMP11 on miRNA and its target genes was explored to confirm its ce-circRNA mechanisms in BC.

Results: qRT-PCR analyses verified that circMMP11 was successfully transfected and positively associated with a poorer clinicopathology of BC. The inhibition of circMMP11 suppressed cell proliferation and migration of BC. The luciferase reporter assay revealed that circMMP11 and MMP11 could bind to miR-1204 and that circMMP11 acted as a ce-circRNA by regulating the expression of MMP11 via sponging miR-1204.

Conclusions: The circMMP11/miR-1204/MMP11 axis regulates breast cancer progression via a competitive endogenous RNA (ceRNA) mechanism. CircMMP11 may serve as a potential therapeutic target in BC.