Identification of microRNA-21 as a valuable diagnostic marker of oral squamous cell carcinoma and potential target

Objective The aim of the study was to summarize the diagnostic value of miR-21 as a biomarker in oral squamous cell carcinoma(OSCC) using a review of the literature and data from the cancer genome atlas(TCGA) database.Methods Data from TCGA database was sorted and analyzed by bioinformatics to determine the expression level of miR-21 in OSCC. Further, we searched for relevant articles in Embase, Pub Med/Medline, Scopus, and Web of Science published before March 2021, extracted the data, and conducted quality assessment. The bivariate meta-analysis model with Stata 16.0 was used to analyze the diagnostic value of miR-21 for OSCC.Results A total of 304 related articles were identified, and seven were selected for meta-analysis. The diagnostic results after analysis were as follows: sensitivity 0.76 [95% confidence interval(CI), 0.57–0.88]; specificity 0.77(95% CI, 0.58–0.89); positive likelihood ratio 3.34(95% CI, 1.58–7.08); negative likelihood ratio 0.31(95% CI, 0.15–0.63); diagnostic odds ratio 10.75(95% CI, 2.85–40.51); and area under the curve 0.83(95% CI, 0.80–0.86). The Deeks’ funnel chart showed that there was no potential bias(P = 0.54). Prediction analysis of the potential target genes of miR-21 was performed via the biological website, and DAVID was used to cross target genes for gene ontology(GO) annotation function analysis.Conclusion The results showed that miR-21-3p and miR-21-5p were significantly more highly expressed in OSCC tissues than in normal tissues(P < 0.05), and the results of the meta-analysis indicated that they could be used as potential biomarkers in the diagnosis of OSCC. In addition, 58 potential target genes of miR-21 were significantly enriched in 28 GO annotation functional pathways, which provided a biological basis for further clinical diagnostic value research.