Autophagy inhibitor-sensitized artificially activated neutrophils against hepatocellular carcinoma

The use of activated neutrophils has emerged as a promising antineoplastic method in oncology. However, challenges, including a short lifespan, susceptibility to the tumor microenvironment, and protumorigenic risks, limit their clinical application. While artificial neutrophils have several limitations, few tumor-related studies have been conducted with constraining factors, including specific targeting inefficiency, immunogenicity and manufacturing challenges. Neutrophil elastase (ELANE), a key antitumor effector in activated neutrophils, is functionally mimicked by porcine pancreatic elastase (PPE), which exhibits selective cancer cytotoxicity. However, PPE triggers protective autophagy in hepatocellular carcinoma (HCC), limiting its therapeutic effectiveness. Methods: To overcome this resistance, we sensitized PPE by the autophagy inhibitor 3-methyladenine (3MA), which is codelivered via tumor-targeting liposomes. This system protects drugs and improves therapeutic efficacy both in vitro and in vivo. Results: 3MA enhanced iron-related ROS-mediated cell destruction induced by PPE while suppressing prosurvival autophagy. The autophagy inhibitor-sensitized artificially activated neutrophils (asAN-P/3) showed precise tumor targeting, excellent therapeutic efficacy, prolonged survival and favorable biocompatibility. Conclusions: We established a precise neutrophil-related tumor therapeutic method (asAN-P/3) and elucidated the mechanistic insights into PPE-mediated therapeutic limitations in HCC. Our study provides a substantial framework for the development of neutrophil-derived antitumor therapeutic strategies in oncology.