RESUMO
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 t0.12),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.
RESUMO
To observe the effect of intaspinal implantation of Schwann cells (SC) genetically modified with microgene pSVPoMcat on spinal cord injury (SCI) repair.120 SD rats were used to establish the hemisected spinal cord injury model at T 8 level,and they were divided randomly into three groups: genetically modified SC implantation group (group A),normal SC implantation group (group B) and control group without cell implantation (group C).One week after the operation ,combined behavioral score(CBS) and the cortical somatasensory evoked potential (GFAP) were measured and the expression of glial fibrillary acidic protein(GFAP) was examined by in situ hybridization and immunocytochemistry.Three months after the operation, all the rats were scanned with MRI and then were sacrificed.Neurofilament (NF) was examined with imunohistocytochemistry staining by using NF monoclonal antibody. Following were the results:(1) In group A,the number of cells expressed GFAP in injured sites was less than that in groups B and C.(2) MRI scanning showed that the SCI region almost recovered in group A but did not recover in group B.There was a malacie focus in SCI region in group C.This was corroborated by the NF staining.(3) The amplitudes of potential in the latent period in group A and B showed a tendency to recover,and it was consistent with CBS.The results suggested that the implantation of genetically modified SC with microgene pSVPoMcat could inhibit GFAP expression and promote the functional recovery of spinal cord injury in rats.