CircRNA_0043691 sponges miR-873-3p to promote metastasis of gastric cancer.

Circular RNAs (circRNAs) are a class of novel RNAs, and aberrant expression of circRNAs has been implicated in human diseases, including gastric cancer (GC). This study aimed to identify the mechanism of circRNA_0043691 in regulating the progression of GC. GSE141977 was downloaded from Gene Expression Omibus ( http://www.ncbi.nlm.nih.gov/geo/ ). Differentially expressed circRNAs were obtained by R software. The expression levels of circRNA_0043691 in GC tissue and normal tissue were identified by quantitative real-time polymerase chain reaction (qRT-PCR). Knockdown of circRNA_0043691 was then constructed and verified by qRT-PCR. Cell viability, migration, and invasion capacity were determined by Cell Counting Kit-8 assay, Transwell migration, and invasion, respectively. Next, knockdown of miR-873-3p was constructed and co-cultured with circRNA_0043691 knockdown to identify whether knockdown of miR-873-3p could attenuate the circRNA_0043691 knockdown on GC cells proliferation, migration, and invasion. The relationship between miR-873-3p and circRNA_0043691 or GART was predicted by bioinformatics tools and verified by dual-luciferase reporter. A total of 211 circRNAs were significantly differentially expressed, including 143 remarkably downregulated circRNAs and 68 significantly upregulated circRNAs. CircRNA_0043691 was upregulated in GC tissue. Knockdown of circRNA_0043691 decreased cell viability, migration, and invasion in GC cells. CircRNA_0043691 has potential putative binding sites with miR-873-3p. Moreover, CircRNA_0043691 positively regulated GART expression by sponging miR-873-3p. Furthermore, knockdown of miR-591 could partially attenuate the si-circRNA_0043691 on the GART expression. GART was upregulated in GC tissue and knockdown of GART could inhibit GC cells proliferation and invasion. Knockdown of circRNA_0043691 delayed the progression of GC via modulating the miR-873-3p-GART axis.