Role of miRNA-340 in modulating gastric cancer cell proliferation and bioinformatic analysis / 南方医科大学学报

ABSTRACT

OBJECTIVE@#To investigate the mechanism of miRNA-340 for regulating the proliferation of gastric cancer (GC) cells and predict its interacting circular RNAs (circRNAs), its downstream target genes and the involved signaling pathways.@*METHODS@#The differentially expressed miRNAs in GC cell lines were analyzed and screened using miRNA microarrays. The expression level of miRNA-340 in 21 pairs of GC tissues and adjacent normal tissues was detected using real-time PCR. MTT and EdU assays were performed to examine the effect of miRNA-340 on the proliferation ability of HFE145 and BGC-823 cells. We also tested the effect of miRNA-340 inhibition on subcutaneous tumorigenesis of GC cells in a nude mouse model. The downstream target genes of miRNA-340 and the probable signal pathways were predicted online using Targetscan and DAVID database, respectively. The interacting circRNAs of miRNA-340 were analyzed using starBase platform.@*RESULTS@#Among the differentially expressed miRNAs, miRNA-340 was significantly down-regulated in GC cell lines. Real-time PCR results showed that the expression of miRNA-340 was significantly lower in GC tissues than in the adjacent tissues ( < 0.05). MTT and EdU cell proliferation assays showed that miRNA-340 overexpression inhibited the proliferation of GC cells in vitro. In the nude mouse models, the proliferation of GC cells transfected with miRNA-340 inhibitor was obviously enhanced. Bioinformatics analysis suggested that miRNA-340 had 21 target genes with 3 or more conserved sites, and these genes were involved in tumorigenesis and invasion. The top 10 circRNAs were selected as the most powerful sponge circRNAs interacting with miRNA-340.@*CONCLUSIONS@#miRNA-340 may play the role of a tumor suppressor in tumorigenesis and progression. Overexpression of miRNA-340 suppress the proliferation of GC cells, suggesting its involvement in the development of GC along with multiple circRNAs.