Molecular Mechanism Of MicroRNA-26b-5p Targeting PRR11 To Inhibit The Proliferation Of Tongue Squamous Cell Carcinoma

Purpose: MicroRNAs(miRNAs)have been confirmed to be involved in biological processes of tumorigenesis and development,including cell proliferation and cell cycle regulation.However,the potential role of miR-26b-5p in tongue squamous cell carcinoma(TSCC)remains to be clarified.The purpose of this study was to study the role of miR-26b-5p in the regulation of TSCC cell proliferation,and to provide new experimental evidence for further analysis of how TSCC cells gain growth advantage.Methods: Firstly,the target gene miR-26b-5p was screened out by bioinformatics analysis of miRNA expression profiles in TCGA-TSCC subsets,and its expression was verified on the collected paired TSCC samples.Transient transfection of miR-26b-5p mimics and inhibitors changed the content in CAL27 cells,and the changes in the proliferation ability of CAL27 cells were detected by CCK-8,Ed U staining and flow cytometry.Combined with online tools and expression correlation analysis,the downstream target genes of miR-26b-5p were predicted,and the targeted regulation between molecules was verified by luciferase reporter gene method and RNA-pulldown assay.Finally,we treated CAL27 cells transfected with miR-26b-5p inhibitor with si RNA of the target gene PRR11 to investigate whether the cell phenotype could be rescued.Results: We found that miR26b-5p was down-regulated in TSCC tissues,while PRR11 was up-regulated in TCGA-TSCC subsets and paired TSCC samples.Through online database prediction,we found that there is a miR-26b-5p binding site in the 3UTR region of the PRR11 gene.Combined with the negative correlation between their expression levels,we speculated that PRR11 is a downstream target gene of miR-26b-5p.Through integrated analysis of expression data and follow-up data in the TCGA database,we found that miR-26b5 p was associated with better patient outcomes,whereas PRR11 gained the opposite result.By CCK-8,Ed U staining and flow cytometry,we found that miR-26b-5p mimics inhibited CAL27 cell proliferation and arrested cells in S/G2 phase,whereas miR-26b-5p inhibitors had the oppositely biological functions.The results of luciferase reporter gene assay and RNA-pulldown assay indicated that miR-26b-5p inhibited PRR11 gene expression by binding to the 3’-UTR of it.Further studies showed that interfering with PRR11 could partially reverse the promoting effect of miR-26b-5p inhibitor on cell proliferation.Conclusion: Taken together,our findings suggest that miR-26b-5p and its target gene PRR11 take important roles in the occurrence,development,and tumor cell proliferation of tongue squamous cell carcinoma.In addition,miR-26b-5p induces cell cycle arrest in tongue squamous cell carcinoma by targeting PRR11.Therefore,the miR-26b-5p/PRR11 axis may be a potential biomarker and therapeutic target for patients with tongue squamous cell carcinoma.