The Expression And Effection Of MicroRNA-499a In High-Tobacco Exposed Head And Neck Squamous Cell Carcinoma

Background: To our knowledge,few studies have directly investigated the differential expression of miRNAs in head and neck squamous cell carcinoma(HNSCC)with low,medium,and high tobacco exposure.The purpose of this study is to screen the differentially expressed miRNAs and to investigate their clinical significance and potential target genes in the three groups of HNSCC.Methods: The datasets of HNSCC were obtained from The Cancer Genome Atlas.The edge R package was used to determine differentially expressed miRNAs and genes among the three groups of HNSCC.Statistical methods were applied to assess the clinical significance of miRNA and its correlation with genes.The correlation between gene expression and clinical characteristics was analyzed using weighted gene co-expression network analysis(WGCNA).Three online databases were used to predict the target genes of miRNAs.RT-qPCR was used to detect the expression of miRNA and genes in HNSCC samples collected from our hospital.Molecular biology experiments were used to preliminarily verify the potential target genes of miRNAs.Results: A total of 32 differentially expressed miRNAs and 1820 differentially expressed genes were found among the three groups of HNSCC.Patients with high expression of miR-499 a had lower overall survival than the ones with low expression in high-tobacco exposed HNSCC.Cox regression analysis found that high expression of miR-499 a and female were independent risk factors for prognosis in high-tobacco exposed HNSCC.Chi-square test found that miR-499 a was associated with N stage in high-tobacco exposed HNSCC.WGCNA,co-expression analysis,and three online databases indicated that AEBP2 and ZNRF1 were potential target genes of miR-499 a.The expression of miR-499 a was continuously upregulated,and the mRNA expression of AEBP2 and ZNRF1 was continuously downregulated in low-,medium-,and high-tobacco exposed HNSCC collected from our hospital.After upregulating the expression of miR-499 a in Hep2 cell line,the mRNA and protein expression of AEBP2 and ZNRF1 were downregulated.After competitive inhibition of miR-499 a in Hep2 cell line,the mRNA and protein expression of AEBP2 and ZNRF1 were upregulated.Conclusions: The patients with high expression of miR-499 a had poor prognoses compared with patients with low expression in high-tobacco exposed HNSCC.The expression of miR-499 a was associated with N stage in high-tobacco exposed HNSCC.AEBP2 and ZNRF1 were the potential target genes of miR-499 a.