A Smart mRNA‐Initiated Theranostic Multi‐shRNA Nanofactory for Precise and Efficient Cancer Gene Therapy

Abstract Despite the significant potential of short hairpin RNA (shRNA)‐mediated gene therapy for various diseases, the clinical success of cancer treatment remains poor, partly because of low selectivity and low efficiency. In this study, an mRNA‐initiated autonomous multi‐shRNA nanofactory (RNF@CM) is designed for in vivo amplification imaging and precise cancer treatment. The RNF@CM consists of a gold nanoparticle core, an interlayer of two types of three‐stranded DNA/RNA hybrid probes, one of which is bound to aptamer‐inhibited DNA polymerases, and an outer layer of the cancer cell membrane. After the specific delivery of RNF@CM into target cancer cells, an intracellular tumour‐related mRNA target can initiate the RNF@CM with a circular strand‐displacement polymerisation reaction, resulting in the release of significantly amplified fluorescence and continuous production of three types of shRNAs. The RNF@CM effectively distinguished cancer cells from normal cells, exclusively produced multiple shRNAs in response to a specific mRNA target in cancer cells, accurately diagnosed tumours in vivo, and significantly inhibited tumour growth with negligible toxicity, expanding the toolbox for on‐demand gene delivery and precision theranostics.