Efficient CRISPR/Cas9 gene-chemo synergistic cancer therapy via a stimuli-responsive chitosan-based nanocomplex elicits anti-tumorigenic pathway effect

Clustered regularly interspaced short palindromic repeat (CRISPR)-associated Cas9 nuclease system (CRISPR/ Cas9) has become a powerful toolbox as a gene fixed-point knock-out method and hold the promising prospect for cancer therapy. However, the biological safety of the viral vectors and the instability of exogenous plasmid in blood circulation limits its application. Herein, we reported a lactobionic acid functionalized and stimuli-responsive chitosan based nanocomplex to co-deliver sgVEGFR2/Cas9 plasmid and paclitaxel for hepatoma carcinoma therapy. The genome editing efficiency of sgVEGFR2/Cas9 in the nanosystem achieved up to 38.6% of HepG2 cells in vitro and 33.4% of tumor tissues in vivo. The nanocomplex suppressed> 60% VEGFR2 protein expression of HepG2 cells and inhibited hepatoma carcinoma (HCC) tumor progress by 70% on mice. In vivo study indicated the obvious tumor accumulation and the good biosafety of the nanosystem. Moreover, the genedrug co-loaded nanoparticles stimulate anti-tumorigenic pathway of HCC by suppressing pro-inflammatory cytokines (IL-6/IL-8) and tumor angiogenesis-related protein (NF-kappa B p65) expression, which revealed the potential pathway inhibition of PTX when combined with the gene therapy for overexpression VEGFR2 on HCC cells. Overall, this strategy provided a versatile method for high efficiency CRISPR/Cas9 system delivery and showed tremendous application prospect for gene-chemo synergistic therapy.