Activation of the cGAS-sting Pathway Mediated by Nanocomplexes for Tumor Therapy.

cGAS (cyclic GMP-AMP synthase)-STING (stimulator of interferon genes) pathway is an natural immune response signaling pathway in the human body that is essential for sensing abnormal DNA aggregation in the cell. When the cGAS protein senses abnormal or damaged DNA, it forms a second messenger called cyclic dinucleotide (cGAMP). The cycled dinucleotide will activate the downstream STING protein, thereby inducing the expression of inflammatory cytokines such as type I interferon, which binds to receptors on its own cell membrane and ultimately initiates multiple immune response pathways. This signaling pathway plays an important immune role in antimicrobial and antitumor functions, etc. so the development of drugs targeting this signaling pathway has important clinical application value. In recent years nanocomplexes based cGAS-STING signaling pathway activation and inhibition treatments have been gradually developed. In this review, on the basis of elaborating the main activation mechanism of the cGAS-STING pathway, we further introduced the nanocomplexes that effectively activate the cGAS-STING pathway, focusing on the composition, types and applications of the nanocomplexes. In addition, we discussed the key challenges and future research directions of the way that stimulating the cGAS-STING signaling pathway in the form of nanocomplexes to activate immuno-tumor therapy. Our work aims to provide a better understanding of the progress of nanotherapeutics in the cGAS-STING pathway, providing a promising anti-tumor therapeutic strategy.