Biodegradable and Efficient Charge-Migrated Z-Scheme Heterojunction Amplifies Cancer Ferroptosis by Blocking Defensive Redox System

Small. 2024 Jun;20(23):e2309206. doi: 10.1002/smll.202309206. Epub 2023 Dec 27.

Abstract

Ferroptosis is an emerging non-apoptotic death process, mainly involving lipid peroxidation (LPO) caused by iron accumulation, which is potentially lethal to the intrinsically apoptotic-resistant malignant tumor. However, it is still restricted by the inherent antioxidant systems of tumor cells and the poor efficacy of traditional iron-based ferroptosis initiators. Herein, the study develops a novel ferroptosis-inducing agent based on PEGylated Cu+/Cu2+-doped black phosphorus@polypyrrole heterojunction (BP@CPP), which is constructed by utilizing the phosphate on the surface of BP to chelate Cu ions and initiating subsequent in situ polymerization of pyrrole. As a novel Z-scheme heterojunction, BP@CPP possesses an excellent photocatalytic activity in which the separated electron-hole pairs under laser irradiation endow it with powerful oxidizing and reducing capacities, which synergy with Cu+/Cu2+ self-cycling catalyzing Fenton-like reaction to further strengthen reactive oxygen species (ROS) accumulation, glutathione (GSH) depletion, and glutathione peroxidase 4 (GPX4) inactivation, ultimately leading to efficient ferroptosis. Systematic in vitro and in vivo evaluations demonstrate that BP@CPP effectively inhibit tumor growth by inducing desired ferroptosis while maintaining a favorable biosafety in the body. Therefore, the developed BP@CPP-based ferroptosis initiator provides a promising strategy for ferroptosis-like cancer therapy.

Keywords: antioxidant inhibition; black phosphorus@polypyrrole; charge migration; fenton‐like reaction; ferroptosis.

MeSH terms

  • Animals
  • Cell Line, Tumor
  • Copper* / chemistry
  • Copper* / pharmacology
  • Ferroptosis* / drug effects
  • Glutathione / metabolism
  • Humans
  • Mice
  • Neoplasms / drug therapy
  • Neoplasms / metabolism
  • Neoplasms / pathology
  • Oxidation-Reduction*
  • Phosphorus / chemistry
  • Polymers / chemistry
  • Polymers / pharmacology
  • Pyrroles / chemistry
  • Pyrroles / pharmacology
  • Reactive Oxygen Species* / metabolism

Substances

  • Reactive Oxygen Species
  • Copper
  • polypyrrole
  • Polymers
  • Pyrroles
  • Glutathione
  • Phosphorus