[Effect of Circular RNA hsa_circ_0067582 on the Proliferation and Invasion Ability of Gastric Cancer Cells]

Objective To investigate the effects on cell proliferation and invasion of the circular RNA hsa_circ_0067582 in gastric cancer(GC). Methods After hsa_circ_0067582 overexpression (Oe-circ_0067582) plasmid was transfected into AGS and SGC-7901 cells,the cell viability,proliferation,invasion ability,and apoptosis were detected by CCK-8,colony formation and EdU assays,Transwell assay,and flow cytometry,respectively.Western blotting was employed to detect the expression levels of proteins related to the cell apoptosis and epithelial-mesenchymal transition(EMT).The effect of Oe-circ_0067582 on the growth of SGC-7901 cells in nude mice was observed.Bioinformatics tools were used to predict the binding target miRNA of hsa_circ_0067582,and the competing endogenous RNA(ceRNA)regulatory network was established.Finally,functional enrichment was performed to analyze the biological functions of the target genes of the predicted miRNA. Results Compared with the pLO-ciR(empty plasmid)group,the Oe-circ_0067582 group in AGS and SGC-7901 cells attenuated the cell viability(t=7.883,P=0.001;t=5.679,P=0.005),proliferation(t=6.709,P=0.003;t=5.857,P=0.003),and invasion ability(t=7.782,P=0.002;t=6.342,P=0.003)and induced cell apoptosis(t=7.225,P=0.002;t=11.509,P=0.001).Western blotting showed that the Oe-circ_0067582 group in AGS and SGC-7901 cells up-regulated the protein levels of cysteinyl aspartate specific proteinase (Caspase) 3(t=6.863,P=0.002;t=7.024,P=0.001),Caspase 7(t=3.295,P=0.04;t=6.008,P=0.004),Caspase 9(t=4.408,P=0.012;t=6.278,P=0.004),and E-cadherin(t=12.453,P=0.002;t=10.867,P=0.001),while down-regulated those of Vimentin(t=7.242,P=0.002;t=5.694,P=0.004)and N-cadherin(t=6.480,P=0.003;t=7.446,P=0.001).Furthermore,Oe-circ_0067582 significantly inhibited the growth of tumor in the SGC-7901 tumor-bearing nude mice(t=3.526,P=0.017).The prediction based on TargetScan and miRnada suggested that hsa_circ_0067582 can competitively bind to hsa-miR-181b-3p,hsa-miR-337-3p,hsa-miR-421,and hsa-miR-548d-3p.The functional enrichment indicated that the target genes of miRNA were involved in multiple cancer-related biological processes including negative regulation of apoptotic process,gene expression,transcriptional misregulation in cancer,transforming growth factor-β,and p53 signaling pathways. Conclusion Oe-circ_0067582 can inhibit the proliferation and attenuate EMT process to reduce the invasion ability of AGS and SGC-7901 cells,which provides a new target for the treatment of GC.