The circRNA circ_0000291 acts as a sponge of microRNA 326 to regulate E26 transformation‐specific sequence‐1 expression and promote breast cancer progression

Abstract

Accumulating studies authenticate that circular RNAs (circRNAs) are involved in the progression of cancers. However, their role in breast cancer (BC) remains largely unknown. In this study, real‐time polymerase chain reaction was employed to detect the circ_0000291 and miR‐326 expressions in BC tissues and cells. The correlation between the expression level of circ_0000291 and clinicopathological parameters of BC patients was analyzed. Western blot was used to detect the expression of E26 transformation‐specific sequence‐1 (ETS1), E‐cadherin, N‐cadherin and Vimentin in BC cells. Cell proliferation was measured using the cell counting kit‐8 assay and the bromodeoxyuridine assay. Cell migration and invasion were detected by Transwell assay. The interactions between circ_0000291 and miR‐326, miR‐326 and ETS1 were verified using bioinformatics prediction, the dual‐luciferase reporter gene assay or/and RNA binding protein immunoprecipitation assay. We demonstrated that circ_0000291 was significantly upregulated in BC, and its high expression was positively correlated with T stage and local lymph node metastasis. Functional assays validated that circ_0000291 promoted BC cell proliferation, migration and invasion. The mechanism studies indicated that circ_0000291 could decoy miR‐326 and in turn upregulate the expression of ETS1. In conclusion, circ_0000291 is the novel oncogenic circRNA and promotes BC progression via modulating the miR‐326/ETS1 axis.

CircRNA RNF10 inhibits tumorigenicity by targeting miR‐942‐5p/GOLIM4 axis in breast cancer

“…CircRNAs are a sort of circular ncRNAs that widely exist in eukaryotes, and their structures are stable and highly conserved (H. D. Zhang, Jiang, et al, 2018). Researches have shown that circRNA is nearly connective with the pathogenesis of tumors and can effectively regulate tumor cells (Min et al, 2020). Previous studies have proposed that various circRNAs, such as circTP63 (Deng et al, 2021), circABCC4 addition, miRNA expression is also regulated by circRNAs, and circ-UBE2D2 could promote the malignant progression of BC through the adsorption of miR-1236 and miR-1287 (Hu et al, 2020).…”

“…CircRNAs are a sort of circular ncRNAs that widely exist in eukaryotes, and their structures are stable and highly conserved (H. D. Zhang, Jiang, et al, 2018). Researches have shown that circRNA is nearly connective with the pathogenesis of tumors and can effectively regulate tumor cells (Min et al, 2020). Previous studies have proposed that various circRNAs, such as circTP63 (Deng et al, 2021), circABCC4 (J. Jiang & Cheng, 2020) and circRNA_0000518 (J. Jiang et al, 2020), promoted the development of breast cancer, while circNOL10 (Wang et al, 2021), circ_SETD2 (Shen et al, 2020) and circRNA_000554 (Mao et al, 2020) had inhibitory effects on the progression of BC.…”

Stachydrine represses the proliferation and enhances cell cycle arrest and apoptosis of breast cancer cells via PLA2G2A/DCN axis

“…As described in a previous study, BrdU staining assay was carried out to assess the proliferation of treated and/or transfected BC cells (Min et al., 2020). Specifically, BC cells to be tested were inoculated in a 6‐well plate with the required confluence of 70%, after which 10 μM BrdU solution (B8010, Solarbio, China) was added to culture the cells at 37°C for 4 h. The medium was subsequently discarded.…”

The Dual Role of Circular RNAs as miRNA Sponges in Breast Cancer and Colon Cancer

“…Circ_WWC3 upregulates the expression of multiple oncogenes in the RAS-signaling pathways by absorbing miR-26b-3p and miR-660-3p [ 55 ]. Several studies reported that other circRNAs also promoted cell migration and invasion; these circRNAs include circ_0011946 [ 56 ], circ_MMP11 [ 57 ], circ_0000291 [ 58 ], circ_MYO9B [ 59 ], and circ_RAD18 [ 60 ].…”