posted on 2021-06-14, 14:34authored byXun Liu, Xingxiang Wang, Sujuan Ye, Ronghua Li, Hongxia Li
Simultaneous
imaging, diagnosis, and therapy can offer an effective
strategy for cancer treatment. However, the complex probe design,
poor drug release efficiency, and multidrug resistance remain tremendous
challenges to cancer treatment. Here, a novel one–two–three
system is built for enhanced imaging and detection of miRNA-21 (miR-21)
overexpressed in cancer cell and chemogene therapy. The system consists
of dual-mode DNA robot nanoprobes assembled by two types of hairpin
DNAs and three-way branch DNAs modified on gold nanoparticles, with
intercalating anticancer drugs (doxorubicin), into DNA duplex GC base
pairs. In the system, via intracellular ATP-accelerated cyclic reaction
triggered by miR-21, fluorescence and SERS signals were alternated
with DNA structure switch, and the precise SERS detection of miRNA
and fluorescence imaging oriented “on-demand” release
of two types of anticancer drugs (anti-miR-21 and Dox) are achieved.
Thus, “one–two–three” means one kind of
miR-21-triggered endogenous substance accelerated cyclic reaction,
two modes of signal switch, and three functions including enhanced
imaging, detection, and comprehensive treatment. The one–two–three
system has some notable merits. First, ATP as an endogenous substance
promotes DNA structure switching and accelerates the cyclic reaction.
Second, the treatment with a dual-mode signal switch is more reliable
and accurate and can provide more abundant information than a single-mode
treatment platform. Thus, the imaging and detection of intracellular
miRNA and effective comprehensive therapy are realized. In vivo results
indicate that the system can provide new insights and strategies for
diagnosis and therapy.