Intracellular miRNA-Triggered Surface-Enhanced Raman Scattering Imaging and Dual Gene-Silencing Therapy of Cancer Cell

ABSTRACT: Development of theranostic nanosystems integrating cascaded surfaceenhanced Raman scattering (SERS) imaging and gene silencing therapy for accurate cancer diagnosis and treatment is still a big challenge and rarely reported. Herein, a novel Au nanoparticles (AuNPs)-based theranostic nanosystem containing AuNP-Ys and AuNP-Ds for highly sensitive and specific cancer diagnosis and treatment was proposed for cascaded SERS imaging of intracellular cancer-related miR-106a and miR-106a-triggered DNAzymebased dual gene-silencing therapy of cancer cells. The AuNP-Ys were prepared by modifying the AuNPs with specially designed Y-motifs, and the AuNP-Ds were obtained by colabeling Raman molecules and dsDNA linkers on AuNPs. When identifying the intracellular cancerrelated miRNAs, the Y-motifs and dsDNA linkers undergoes miRNA-triggered ATP-driven conformational transitions and releases the miRNA for recycling, which results in the formation of AuNP network nanostructures to generate significantly enhanced SERS signals for sensitive identification of the cancer cells as well as the amplification and specific activation of DNAzymes to catalyze the Mg2+-assisted cleavage of the Survivin and c-Jun mRNAs for effective dual gene-silencing therapy of cancer cells. The AuNP-based theranostic nanosystem achieves the synergism of target-triggered SERS imaging and DNAzyme-based dual gene-silencing therapy with enhanced specificity, sensitivity, and curative effect, which can be a powerful tool for accurate diagnosis and efficient treatment of cancers.

Automated summary

This study proposed a gold nanoparticle (AuNP)-based theranostic nanosystem for highly sensitive and specific cancer diagnosis and treatment. The system utilizes cascaded surface-enhanced Raman scattering (SERS) imaging of intracellular cancer-related miRNA and miRNA-triggered DNAzyme-based dual gene silencing therapy of cancer cells. The system achieves the synergism of target-triggered SERS imaging and DNAzyme-based dual gene silencing therapy with enhanced specificity, sensitivity, and curative effect.