MicroRNA-34a Inhibits Biological Behaviors Of Urothelial Carcinoma Cell Line J82by Targeting Notch1

Objective: To clarify the the role of miR-34a in regulating Notch1expression andinvestigate the effect of forced expression of miR-34a on biological behavior inurothelial carcinoma cell line J82. Methods: miR-34a was predicted as a putative genewhich can target Notch1through bioinformatics analysis. J82cells were transfectedwith pcDNA3.0-miR-34a or pcDNA3.0control plasmid. qRT-PCR and Western blotwas performed to measure the expression levels of Notch1and miR-34a respectively inJ82Cells which were transfected with miR-34a or empty expression plasmid.Luciferase assay was employed to determine if miR-34a could target Notch1by bindingto the3’UTR (3’-untranslated region) of Notch1mRNA. MTS was used to evaluate theeffect of miR-34a expression on cell proliferation. The effect of miR-34a expression onapoptosis and cell cycle were assessed by staining for PI(propidium iodide). The effectof miR-34a expression on cell migration and invasion were assessed by using transwellassay. Results: When the miR-34a expression plasmid was transfected into J82cells,the expressive level of miR-34a was highly induced and the expressive level of Notch1mRNA and protein obviously decreased, meanwhile, cellular proliferation wereinhibited, the capability of cell migration and invasion were decreased, apoptosis wereincreased, cell cycle arrested were observed. The results of luciferase assay show thatmiR-34a exert its regulatory effects by binding to the3’UTR of Notch1mRNA.Conclusions: miR-34a targets Notch1via binding to the3’UTR of Notch1mRNA. Theforced expression of miR-34a in urothelial carcinoma cell line J82inhibits cellmalignancy such as cellular proliferation, migration and invasion and induces apoptosisand cell cycle arrested. miR-34a can act as a potential tumor suppressor by regulating Notch1in urothelial carc inoma.