Dual-RNA controlled delivery system inhibited tumor growth by apoptosis induction and TME activation

Drug-controlled release is recognized as effective for improving compliance with treatment and obtaining better therapeutic efficacy with less toxicity in cancer treatment. However, few reports in this area are involved in nucleic acids delivery, especially in RNA therapeutics delivery. In this study, an injectable hydrogel Methacrylated gelatin (GM) scaffold was introduced into a dual-RNA hybrid delivery complex hybrid lipid particle (HLP) to form a G-HLP/RNAs system. This system can control the release of both siRNA and mRNA and was found to be efficient for protecting these RNAs from biodegradation and retaining their therapeutic effect over 7 days. Further, a tumor environment (TME)-activation function after peritumoral injection of mocked GM scaffold was observed. Then, matured DC cells and activated T-cells were detected by the addition of HLP/RNAs complex, thus verifying the immunoactivation function of GM scaffold and its ability to reserve immune cells and antigens. Finally, two doses of G-HLP/RNAs treatment efficiently suppressed C26 tumor growth in mice with a tumor weight inhibition rate of 71.9%. Owing to its ability to achieve RNA drug-controlled release, alter TME, and induce tumor apoptosis, the G-HLP/RNAs system may become a valuable tool for cancer gene therapy.