DPP4 and type 2 diabetes mellitus: Cho used lecithin nano-liposome particle as a CRISPR/Cas9 complex delivery system for treating type 2 diabetes by downregulating the expression of enzyme dipeptidyl peptidase-4 (DPP-4) gene, which can block the degradation of glucagon-like peptide-1 (GLP-1) by DDT-4 [190].