Role And Mechanism Studies On Pygo2-miRNA In Human Glioma

The Pygopus2(Pygo2) proteins are critical elements in the Wntsignaling pathway, which is exhibited a positive correlation with gliomatumors grade. The mechanisms regulating Pygo2gene activation, however,are unknown. This study provides theoretical evidence for the microRNAas negative regulators of gene expression by binding to Pygo2.Object: To stuady the role and mechanism studies on miRNA by targetingPygo2in human glioma.Methods: Using an in silico approach（targetscan，miRanda and PicTar）and miRNA microarrays, we identified candidate miRNAs that might targetthe3′UTR of Pygo2. Luciferase assays involving deletion mutants of Pygo23′UTR luciferase vectors revealed that miR-214directly targets thePygo23′UTR. Furthermore, we found that Pygo2over-expression wasinversely correlated with miR-214expression. miR-214can inhibit cellproliferation, migration and invasion by down-regulating Pygo2mRNA inglioma cells.Results: We screened37candidate miRNAs that may target Pygo2by acombinatorial use of three different bioinformatics software. Aftercombining the bioinformatics software with the results from our miRNAmicroarrays, we discovered that Pygo2could be regulated by13miRNAs.Luciferase reporter assays combined with those of western blot analysisand quantitative real-time PCR assays, indicate that miR-214is a likelypotential candidate miRNA as it represses pygo2expression more thanothers in glioma cells. The upregulation of miRNA-214reduced theproliferation and aggressiveness of glioma cells in vitro.Conclusion: In summary,this study demonstrated that Pygo2over-expression was inversely correlated with miR-214expression, and miR-214can inhibit cell proliferation, migration and invasion bydown-regulating Pygo2mRNA in glioma cells. Targeting miR-214may providea better strategy in undermining tumor proliferation, migration andinvasion. The miRNAs identified in this study may serve as candidatebiomarkers for diagnostic and prognostic purposes for treatmentstratification in the future.