Background:In our previous paper,we demonstrated that Connexin 43(CX43)was highly expressed in bladder cancer(BC)tissues.But the molecular mechanism about microRNAs(miRNAs)regulation upstream of CX43 in BC has not been well elucidated and remains to be further studied.MicroRNA-139-5p(miR-139-5p)is a tumor suppressor in progression of multifarious cancers including BC.Nevertheless,the underlying mechanisms of CX43/miR-139-5p in tumorigenesis of BC are still not well illustrated.The specific objective of our study was to inquiry the effect of CX43/miR-139-5p on BC progression and its underlying mechanism.Methods:The bioinformatics analysis softwares were applied to predict the miRNAs in the upstream of CX43.First,the expression levels of miR-139-5p in BC tissues(tumor)and paracancer tissues(normal)were investigated using the data from The Cancer Genome Atlas database.Quantitative reverse transcription-polymerase chain reaction(qRT-PCR)was used to detect the mRNA expression level of miR-139-5p in three human BC cell lines 5637,T24,ECV-304 and a human bladder epithelial immortalized cell line SV-HUC-1(normal control).Then si-CX43,si-control,miR-139-5p mimic,and its negative control(NC)were transfected into BC cell line ECV-304.The relationship of miR-139-5p and CX43 was analyzed by dual-luciferase reporter assay.The qRT-PCR and Western blotting were used to test the mRNA and protein expression level of CX43.The proliferation of ECV-304 and T24 cells were examined by cell counting kit-8.The migration and invasion of ECV-304 cells were tested by transwell assay.To determine whether miR-139-5p would affect cell proliferation,migration and invasion by targeting CX43,we executed the rescue assay.The comparison between two groups was analyzed by Student’s t test,and comparisons among multiple samples were performed by oneway analysis of variance and a Bonferroni post hoc test.Results:The expression of miR-139-5p was remarkably down-regulated in BC tissues(tumor vs.normal,2.286±0.017 vs.3.211±0.034,t=11.540,P<0.0001)and
Qiang ChiZhi-Yong WangHong-Yang LiDian-Bin SongHui XuGuang MaZe-Min WangXiu-Ming Li
