Long noncoding RNA CA3-AS1 suppresses gastric cancer migration and invasion by sponging miR-93-5p and targeting BTG3

The long noncoding RNAs (lncRNAs) are a class of noncoding RNAs that are broadly expressed in various biological cells and function in regulating gene expression. However, the function of lncRNAs and the role of lncRNAs in gastric cancer remain to be determined. Herein, the function of lncRNA CA3-AS1 was investigated in gastric cancer. Firstly, we found that the expression level of CA3-AS1 was decreased in gastric cancer cell lines and tissues. Then, CA3-AS1 overexpression inhibited the gastric cancer cells migration and invasion and knockdown of CA3-AS1 enhanced the gastric cancer cells migration and invasion. Moreover, FISH assays and qPCR results revealed that CA3-AS1 was mainly expressed in the cytoplasm of gastric cancer cells. Then, the relationship between CA3-AS1 and miR-93-5p was explored. Luciferase reporter assays results showed that miR-93-5p was a direct target of CA3-AS1 in SGC-7901 and BCG-823. Furthermore, BTG3 was identified as a direct target gene of miR-93-5p. Restore experiments showed that CA3-AS1 upregulated the expression level of BTG3 and inhibited the gastric cancer cells invasion by sponging miR-93-5p. Finally, we found that CA3-AS1 inhibited the metastasis ability of gastric cancer cells in vivo. Above results suggested that CA3-AS1 acted as anti-oncogene in gastric cancer and might become a vital target for clinical treatment.