Hsa_hsa_circ_0081069 promotes the progression of colorectal cancer through sponging miR‐665 and regulating E2F3 expression

BACKGROUND: Circular RNAs (circRNAs) have been implicated in the initiation and development of various cancers. This study explored the potential contribution of hsa_hsa_circ_0081069 in the progression of colorectal cancer (CRC). METHODS: The gene expression was analyzed by qRT‐PCR. Functional roles of hsa_circ_0081069 were examined by shRNA‐mediated silencing using CCK‐8 proliferation assay, Transwell migration and invasion assay, tube formation assay. The tumorigenesis and metastasis of CRC cells were assess in a xenograft mouse model. RESULTS: Hsa_circ_0081069 was significantly upregulated in CRC tissues and cells. Hsa_circ_0081069 knockdown suppressed the proliferation, migration and invasion in CRC cells, as well as the angiogenesis. Silencing hsa_circ_0081069 also impaired the tumorigenesis of CRC cells in a xenograft mouse model. Furthermore, miR‐665 was identified as an interacting partner of hsa_circ_0081069, which was negatively regulated by hsa_circ_0081069. miR‐665 targeted the mRNA of E2F3 to suppress its expression. We further demonsatred that miR‐665/E2F3 axis mediated the functional role of hsa_circ_0081069 in regulating the malignant phenotype of CRC cells. CONCLUSIONS: Collectively, our study suggests that hsa_circ_0081069 could serve as a prognostic marker in progression of CRC. Targeting hsa_circ_0081069 and miR‐665/E2F3 axis could serve as potential therapeutic strategies for CRC treatment.