A Self‐Catabolic Multifunctional DNAzyme Nanosponge for Programmable Drug Delivery and Efficient Gene Silencing

DNAzyme-based gene therapy holds immense prospects for effectively treating severe diseases, yet is constrained with inefficient delivery and unconditional activation. Herein, we designed a bioinspired self-catabolic DNA nanocapsule for sustaining tumor-specific cascade activation of therapeutic DNAzyme. The exquisite DNAzyme was temporarily masked by the self-excising DNAzyme in the hierarchical rolling circle replication (RCR) nanostructures, thus stayed in an inactive state in physiological fluids. Through the multivalent tumor-anchoring aptamer strands, the RCR nanocapsule was specifically accumulated in cancer cells and was sequentially activated for motivating the ultimate DNAzyme-mediated gene silencing via the intelligent stimuli-responsive cascade DNAzyme activation. By virtue of the programmable RCR assembly strategy, our compact DNAzyme nanoplatform shows great promise for developing versatile smart gene therapeutics and personalized nanomedicines.