Cancer gene therapy by NF-κB-activated cancer cell-specific expression of CRISPR/Cas9 targeting to telomere

Abstract

NF-{kappa}B has been a luring target for cancer therapy due to its over activation in all tumors. In this study, we showed that a gene therapy named as NF-{kappa}B-activated gene expression (Nage) could be used to induce cancer cell death in vitro and in vivo by utilizing the NF-{kappa}B activity in cancer cells; however, it had no effect on normal cells. In this gene therapy, we constructed a NF-{kappa}B-specific promoter by fusing a NF-{kappa}B decoy sequence to a minimal promoter, which could be bound by the intracellular over activated NF-{kappa}B and thus activate the expression of downstream effector gene in a NF-{kappa}B-specific manner. In this study, we firstly demonstrated the cancer cell-specific activation of NF-{kappa}B. We then demonstrated the cancer cell specificity of Nage vector expression by introducing a Nage vector that could express a reporter gene ZsGreen in various cell lines. We next demonstrated that a Nage vector that could express CRISPR/Cas9 protein and a telomere-targeting sgRNA could be used to specifically induce death of cancer cells. We finally showed that the Cas9/sgRNA Nage vector packaged into the adeno-associated virus (AAV) could be used to inhibit the growth of xenografted tumors in mouse by intravenously injecting recombinant AAV.