Abstract
Gastric cancer (GC) is one of the most common malignant tumors. Circular RNA (circRNA) has been shown to be involved in the progression of GC. However, the function of circ_0008035 in GC has not been studied. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect the expression of circ_0008035, microRNA-1256 (miR-1256) and carcinoembryonic antigen-related cell adhesion molecule 6 (CEACAM6). 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay, 5-ethynyl-2'-deoxyuridine (EdU) assay, flow cytometry, and transwell assay were used to detect cell function. Western blot examined the protein levels of Ki67, Bax, MMP-2, and CEACAM6. The relationship between miR-1256 and circ_0008035 or CEACAM6 was verified by dual-luciferase reporter assays and RNA pull down. The xenotransplantation model was established in BALB/c nude mice to study the role of circ_0008035 in vivo. Circ_0008035 and CEACAM6 were significantly high-expressed in GC tissues and cells. Silencing of circ_0008035 reduced GC cell proliferation, migration, and invasion while enhancing apoptosis. MiR-1256 was a target of circ_0008035. The inhibition effect of circ_0008035 knockdown on the malignant behavior of GC cells could be reversed by miR-1256 inhibitor. In addition, CEACAM6 was a target of miR-1256. Overexpression of CEACAM6 partially restored the inhibitory effect of miR-1256 on cell progression. Animal experiments confirmed the anti-tumor effect of circ_0008035 knockdown in vivo. Collectively, circ_0008035 regulated the expression of CEACAM6 by sponging miR-1256, thereby promoting the development of GC. Our data provided a novel targeted therapy for GC.