Background: MicroRNAs (miRNAs) are small noncoding RNA molecules involved in the post-transcriptional regulation of genes. Deregulated expression of miRNAs is involved in different pathogenic mechanisms, particularly colorectal cancer (CRC) carcinogenesis. Due to their stability and accessibility, circulating miRNAs represent a new family of biomarkers with great potential. Therefore, certain miRNAs can be used as diagnostic biomarkers in CRC.
Objective: This systematic analysis aimed to explore the individual efficacy of the most investigated blood-based miRNAs for CRC diagnosis, namely miR-21, miR-29a and miR-92a.
Methods: Articles were retrieved from databases such as PubMed and Google Scholar, and studies designed to evaluate the diagnostic value of microRNAs in CRC were then selected. We subsequently explored the diagnostic accuracy of each miRNA using parameters such as (SE, SPE, PLR, NLR). The meta-analysis was performed using the Review Manager (Revman) 5.4 software and the Meta Disc software.
Results: Our results suggested that serum miR-21 levels showed great potential as a diagnostic molecular marker. The overall pooled results for sensitivity, specificity, area under the curve (AUC), PLR, and NLR were 78%, 91%, 0.9519, 8.12 and 0.17, respectively.
Conclusion: miRNAs have become increasingly important in the diagnosis of CRC. Based on these findings, circulating miR-21 levels may have a potential value for early detection and might be used as a novel diagnostic biomarker for CRC.
Keywords: Colorectal, cancer, microRNA, serum, diagnostic, biomarker, miR-29a, miR-92a, miR-21, meta-analysis