High-throughput quantitative detection of triple-negative breast cancer-associated expressed miRNAs by rolling circle amplification on fluorescence-encoded microspheres

Compared with other types of breast cancer, triple-negative breast cancer (TNBC) has the characteristics of a high degree of malignancy and poor prognosis. Early diagnosis of TNBC through biological markers and timely development of effective treatment methods can reduce its mortality. Many Research experiments have confirmed that some specific miRNA expression profiles in TNBC can used as markers for early diagnosis. However, detecting the expression profiles of multiple groups of miRNAs according to traditional detection methods is complicated and consumes many samples. To address this issue, we developed a method for high-throughput, high-sensitivity quantitative detection of multiple sets of miRNAs (including miR-16, miR-21, miR-92, miR-199, and miR-342) specifically expressed in TNBC by rolling circle amplification (RCA) on fluorescence-encoded microspheres. Through the optimization of reaction system conditions, the developed method showed an extensive linear dynamic range and high sensitivity for all five miRNAs with the lowest limit of detection of 2 fmol/L. Meanwhile, this high-throughput detection method also appeared reasonable specificity. Only in the presence of a specific target miRNA, the fluorescence signal on the correspondingly encoded microspheres is significantly increased, while the fluorescence signal on other non-correspondingly encoded microspheres is almost negligible. Furthermore, this process exhibited good recovery and reproducibility in serum. The advantages of this method allow us to more conveniently obtain the expression profiles of multiple groups of TNBC-associated miRNAs, which is beneficial for the early detection of TNBC.