Self-Assembled Plasmid Delivery System for PPM1D Knockout to Reverse Tumor Malignancy

Gene delivery vectors possess critical roles in effective genome editing. In this study, a multiple functional vector for encapsulating CRISPR/Cas9 plasmid was designed to knock out PPM1D gene and prevent cancer malignancy. The plasmid was complexed with a KALA peptide with the capability of endosomal escape and histones for nuclear transportation and then decorated by hyaluronic acid (HA) and AS1411-incorporated hyaluronic acid (AHA) targeting CD44 and nucleolin overexpressed in cancer cells to form AHA/HA/KALA/histone/plasmid nanoparticles. The constructed multifunctional plasmid delivery system with the cancer targeting specificity can realize efficient genome editing for PPM1D knockout and thus dramatically downregulate PPM1D expression in targeted malignant cells. More importantly, PPM1D knockout results in upregulation of p21 and p-p38 as well as downregulation of cyclin D1, MMP9, CYR61, and vimentin. The edited cancer cells exhibit suppressed proliferation, migration, and invasion, indicating the successful reversal of tumor malignancy.