A comprehensive investigation of identifying miRNA biomarkers and their potential role in age-related cataract by meta-analysis and bioinformatics analysis.

Purpose: Age-related cataract (ARC) remains one of the leading causes of blindness globally. Despite the satisfactory outcomes of surgical interventions, significant disparities in access to medical care prevent many patients from receiving effective treatment. Thus, identifying reliable biomarkers and therapeutic targets to expand treatment options for ARC is essential. Recent evidence indicates that microRNAs (miRNAs) play a role in the development of cataracts and may serve as promising biomarkers. Consequently, this study aims to investigate miRNAs' levels and potential functions in ARC.

Methods: We conducted a meta-analysis following the PRISMA guidelines by searching three databases from inception to March 31, 2023. The quality of the articles was assessed using the NOS. Subsequently, the targets of the miRNAs identified in the meta-analysis were predicted using six databases, and their GO functions and KEGG pathway enrichment information were analyzed via DAVID.

Results: An initial search yielded 225 publications, from which 22 miRNAs across 37 studies were selected for our meta-analysis. We identified eight differentially expressed miRNAs (DEmiRNAs) in ARC, comprising two up-regulated miRNAs (miR-124 and miR-125a) and six down-regulated miRNAs (miR-15a, miR-23b, miR-34a, miR-221, miR-222, and miR-378a). A total of 972 targets for these miRNAs have been confirmed, and subsequent bioinformatics analysis has revealed their potential functions and pathways in various ARC-related processes.

Conclusions: This study indicates that eight differentially expressed miRNAs (miRNA-15a, miRNA-23b, miRNA-34a, miRNA-124, miRNA-125a, miRNA-221, miRNA-222, and miRNA-378a) may serve as biomarkers for ARC. Bioinformatics analyses suggest varied potential roles for each miRNA, providing a framework for future research in ARC. This systematic evaluation represents the initial depiction of the miRNA-biomarker landscape in ARC.

Key Messages: What is known MicroRNAs(miRNAs) could serve as biomarkers for age-related cataract(ARC) since their abundances are associated with ARC and can play a role in cataractogenesis. However, existing studies have reported inconsistent results regarding the miRNA level in ARC. Therefore, achieving a consensus on the role of miRNAs in ARC is essential to clarify their involvement. What is new This study suggested that eight differentially expressed miRNAs (miRNA-15a, miRNA-23b, miRNA-34a, miRNA-124, miRNA-125a, miRNA-221, miRNA-222, and miRNA-378a) may serve as biomarkers for ARC. Our bioinformatics analysis identified various potential roles for each miRNA, which could guide future research on ARC.