Circ_0000554 is identified as a cancer-promoting circRNA in colorectal cancer by regulating the miR-1205/LASP1 axis

Background Colorectal cancer (CRC) is a prevalent malignant tumor with poor prognosis. Circular RNAs (circRNAs) are key regulators in the progression of CRC. Our study aimed to disclose the role of circ_0000554 in CRC. Methods The expression of circ_0000554, miR-1205 and LIM and SH3 protein 1 (LASP1) was measured by quantitative real-time polymerase chain reaction (qRT-PCR). Cell proliferation, invasion and migration were monitored using cell counting kit-8 (CCK-8) assay, EdU assay, transwell assay and wound healing assay respectively. The protein levels of C-myc, matrix metallopeptidase 2 (MMP-2) and LASP1 were detected by western blot. Tumor formation assay in nude mice was conducted to explore the role of circ_0000554 in vivo. The association between miR-1205 and circ_0000554 or LASP1 was identified by dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay. Results circ_0000554 was upregulated in CRC tissues and cells, high circ_0000554 expression was significantly linked to shorter overall survival. Downregulation of circ_0000554 restrained cell growth and metastasis while promoted apoptosis in vitro, and suppressed tumorigenesis of CRC in vivo. Furthermore, mechanism study and rescue experiments confirmed miR-1205 could be sponged by circ_0000554 and its inhibitor reversed the inhibitory effect of circ_0000554 silencing on CRC progression. LASP1 was a target gene of miR-1205 and the upregulation of LASP1 overturned miR-1205-induced effects on CRC cells. Circ_0000554 could elevate LASP1 expression via interacting with miR-1205.