Effect of miR-758-3p on invasion and proliferation of gastric cancer cell line MGC803 by targeting MDM2

Abstract

Objective To observe the regulation of microRNA (miRNA, miR)-758-3p on the expression of murine double microsomal gene 2 (MDM2) and its effect on invasion and proliferation of gastric cancer cell line MGC803. Methods The bioinformatics software was used to predict MDM2 as target gene of miR-758-3p. The wild type MDM2 gene 3 ′untranslated region luciferase reporter gene vector and miR-758-3p target sequence mutated vector and the corresponding miRNA were transfected into gastric cancer cells MGC803 by lipofectamine. Dual luciferase reporter system detects luciferase activity. The miR-758-3p mimics were transfected into gastric cancer cell MGC803 by lipofectamine. Real-time PCR was used to detect the transfection efficiency. Real-time PCR and Western blot were used to detect miR- MDM2 expression level in cells after transfection. Transwell assay and CCK-8 assay were used to detect cell invasion and proliferation. SPSS 20.0 was used to conduct the statistical analysis. Results Dual luciferase reporter assay confirmed that miR-758-3p could target MDM2 gene(P<0.05). The expression level of miR-758-3p in MGC803 cells transfected with miR-758-3p mimics was significantly higher than that in miR-NC cells [(6.68±0.53) vs (0.84±0.12), P<0.01]. Compared with miR-NC group, MDM2 expression was down-regulated in MGC803 cells transfected with miR-758-3p mimics (P<0.05). The number of invasive cells in miR-NC group and miR-758-3p group were (136.00 ±16.62)and (79.49±6.42). After knockdown MDM2, the invasiveness of cells was significantly decreased (P<0.05). The results of CCK-8 showed that the proliferation of MGC803 cells transfected with miR-758-3p group was significantly lower than that of miR-NC group (P<0.01). Conclusion miR-758-3p can reduce the invasion and proliferation of MGC803 cells by targeting MDM2. Key words: Stomach neoplasms; MicroRNAs; Neoplasm invasiveness; Cell proliferation; Murine double micro-gene 2