The Study Of MiRNA-128-3p Targeting Regulation-Musashi-1 Inhibits The Growth Of Medullblastoma

Background: Medulloblastoma(MB)is the most common malignancy in childhood brain tumors.The incidence of MB accounts for nearly 10% of all childhood brain tumors.MB is characterized by high invasion,easy spread,and difficult to cure.Current treatment approach for MB includes complete resection and postoperative radiotherapy and chemotherapy of whole brain and spinal cord.With continuous optimization of treatment approaches,the 5-year survival rate can improve 50-80%,but serious postoperative adverse events often occur and cause poor prognosis.It is quite necessary to further explore the pathogenesis of MB and develop novel,effective and less side effect treatments regimens.With the discovery of the role and mechanism of miRNAs in diseases,its function in MB has been gradually unveiled.MiRNA-128-3p has been proved to be down-regulated in a variety of tumors and is associated with occurrence,development and prognosis.But the effect of miRNA-128-3p on the occurrence and development of MB and its pathogenesis needs to be further studied.Objective: 1.To find differentially expressed miRNAs in MB tissues through bioinformatics,analyze the expression of miRNA-128-3p in MB tissues.2.DAOY cells were selected to study the effects of miRNA-128-3p on the proliferation,migration,invasion and apoptosis of medulloblastoma cells.3.Predict and validate the target gene of miRNA-128-3p to study the molecular mechanism by which miRNA-128-3p inhibits medulloblastoma growth.Methods: 1.Screen the abnormally expressed miRNAs in MB using the bioinformatics website,and detect the expression level of miRNA-128-3p in MB by real-time fluorescence quantitative PCR.2.Using DAOY cell line as the research object,miRNA-128-3p was over-expressed in MB �by transfection with miRNA-128-3p mimic.The effects of miRNA-128-3p on the migration,invasion,proliferation,and apoptosis of DAOY cells were detected by cytometry.3.Using bioinformatics to predict and screen the target gene of miRNA-128-3p as Msi1.Western blot and qRT-PCR were used to detect the expression level of Msi1 in MB tissue and DAOY cells.Results: 1.The abnormal miRNA expression was screened as miRNA-128-3p using the GEO database.The expression of miRNA-128-3p in MB and normal brain tissue was detected by qRT-PCR.The results showed that the expression of miRNA-128-3p was down-regulated in MB.2.The results of cell scratch test and Transwell test showed that overexpression of miRNA-128-3p could inhibit the invasion and migration of MB.3.The results of CCK-8 proliferation experiments show that overexpression of miRNA-128-3p could inhibit the proliferation of MB.4.Flow cytometry showed that overexpression of miRNA-128-3p could induce apoptosis of MB cells.5.Msi1 may be a downstream target gene of miRNA-128-3p predicted by bioinformatics website.Western blot and qRT-PCR were used to detect the expression of Msi1 in MB tissue,normal brain tissue and DAOY cells.The results suggested that Msi1 was highly expressed in medulloblastoma tissues,and miRNA-128-3p could target and regulate Msi1 to further affect the occurrence and development of MB.High expression in cell tumor tissues.Conclusions: miRNA-128-3p expression is decreased in MB tissues,which further inhibits the invasion,migration,proliferation,and induces apoptosis of MB cells by targeting and regulating the expression of Msi1.