MicroRNAs (miRNAs) have been recognised as potential biomarkers due to their specific expression patterns in different biological tissues and their changes in expression under pathological conditions. MicroRNA-122 (miR-122) is a vertebrate-specific miRNA that is predominantly expressed in the liver and plays an important role in liver metabolism and development. Dysregulation of miR-122 expression is associated with several liver-related diseases, including hepatocellular carcinoma and drug-induced liver injury (DILI). Given the potential of miR-122 as a biomarker, its effective detection is important for accurate diagnosis. However, miRNA detection methods still face challenges, particularly in terms of accurately identifying miRNA isoforms that may differ by only a single base. Here, with the aim of advancing accessible methods for the detection of miRNAs with single-base specificity, we have developed a robust dual nanosystem that leverages the simplicity of click chemistry reactions. Using the dual nanosystem, we successfully detected miR-122 at single-base resolution using flow cytometry and analysed its expression in various tumour cell lines with high specificity and strong correlation with TaqMan assay results. We also detected miR-122 in serum and identified four single nucleotide variations in its sequence. The chemistry employed in this dual nanosystem is highly versatile and offers a promising opportunity to develop nanoparticle-based strategies that incorporate click chemistry and bioorthogonal chemistry for the detection of miRNAs and their isoforms.Graphical
Read full abstract