Biodegradable, multifunctional DNAzyme nanoflowers for enhanced cancer therapy

Safety and efficiency remain the critical hurdles hindering the practical application of gene agents, even though great effort has been made to develop various gene carriers. Herein, we present a novel biodegradable cancer therapeutic system based on DNA nanoflowers (DNFs) for targeted dual gene silencing. The therapeutic system was constructed by copying a rolling circle amplification template to produce long single-stranded DNAs with cell targeting and dual gene-silencing capability. The structure of the DNFs collapsed at acidic pH due to the decomposition of the co-assembled magnesium pyrophosphate, generating Mg2+ ions that act as cofactors for the DNAzymes and increase their ability to recognize and cleave target mRNAs. In vitro and in vivo studies demonstrated that the multifunctional DNFs showed promise for targeted cancer cell recognition, gene silencing, induction of apoptosis and inhibition of tumor growth. Considering the enhanced therapeutic effect and biocompatibility of this therapeutic platform, it is anticipated to be of great interest for the clinical treatment of cancers.