Beijing Advanced Innovation Center for Food Nutrition and Human Health, Beijing Technology and Business University (BTBU), 11 Fucheng Road, Beijing, 100048, China.
Beijing Key Laboratory for Bioengineering and Sensing Technology, Research Center for Bioengineering and Sensing Technology, School of Chemistry and Bioengineering, University of Science & Technology Beijing, 30 Xueyuan Road, Beijing, 100083, China.
Anal Bioanal Chem. 2019 Jul;411(19):4559-4567. doi: 10.1007/s00216-019-01753-x. Epub 2019 Apr 11.
Mature microRNAs (miRNAs) are small-sized RNAs cleaved from precursor microRNAs (pre-miRNAs) by the RNase Dicer. Various miRNAs play key regulatory roles in tumorigenesis and metastasis, and are therefore potential diagnostic and prognostic cancer biomarkers. However, detecting miRNAs and pre-miRNAs accurately and selectively in living cells remains a major challenge, as the mature miRNA sequence is also present in its pre-miRNA and current sequence probes exhibit poor gene delivery efficiency. Herein, we report a strategy for selectively and accurately detecting miRNA-21 and pre-miRNA-21 in living cells using functional MoS nanosheets (NSs) loaded with rationally engineered molecular beacons (MBs). The exfoliated MoS nanosheets (NSs) with a mean lateral diameter of 50-70 nm were functionalized with the aptamer AS1411 and polyethylene glycol (MoS-PEG-AS) to achieve target-cell-specific delivery and to enhance biocompatibility. The large available surface of the MoS-PEG-AS was loaded with MB probes. The resulting MoS-PEG-AS/MBs present cancer-cell-targeting ability, good protection properties, good optical stability, and biocompatibility. We demonstrated that the resulting nanoprobes can selectively image miRNA-21 and pre-miRNA-21 in various cell lines by facilitating enhanced fluorescence in the presence of miRNA-21 and pre-miRNA-21. Thus, these MoS-PEG-AS/MBs are potentially a tool to discriminate between intracellular miRNA and pre-miRNA at different expression levels. Graphical abstract.
成熟的 microRNAs (miRNAs) 是由 RNase Dicer 从 miRNA 的前体 (pre-miRNAs) 中切割出来的小 RNA。各种 miRNAs 在肿瘤发生和转移中发挥关键的调节作用，因此是潜在的诊断和预后癌症生物标志物。然而，在活细胞中准确和选择性地检测 miRNAs 和 pre-miRNAs 仍然是一个主要挑战，因为成熟 miRNA 的序列也存在于其 pre-miRNA 中，并且当前的序列探针显示出较差的基因传递效率。在此，我们报告了一种使用功能化 MoS 纳米片 (NS) 负载合理设计的分子信标 (MB) 来选择性和准确检测活细胞中的 miRNA-21 和 pre-miRNA-21 的策略。剥离的 MoS 纳米片 (NS) 具有 50-70nm 的平均横向直径，并用适配体 AS1411 和聚乙二醇 (MoS-PEG-AS) 功能化，以实现靶细胞特异性传递并提高生物相容性。MoS-PEG-AS 具有较大的可用表面，可负载 MB 探针。所得的 MoS-PEG-AS/MB 具有癌细胞靶向能力、良好的保护性能、良好的光学稳定性和生物相容性。我们证明，所得的纳米探针可以通过促进 miRNA-21 和 pre-miRNA-21 存在时的荧光增强，选择性地对各种细胞系中的 miRNA-21 和 pre-miRNA-21 进行成像。因此，这些 MoS-PEG-AS/MB 有可能成为区分不同表达水平的细胞内 miRNA 和 pre-miRNA 的工具。图摘要。
