Blocking Metallothionein-2 Expression by Copper-Doped Carbon Dots Induces Cellular Antioxidant System Collapse for Antitumor Therapy

Nano Lett. 2024 Aug 28;24(34):10699-10709. doi: 10.1021/acs.nanolett.4c03418. Epub 2024 Aug 14.

Abstract

The insufficient antioxidant reserves in tumor cells play a critical role in reactive oxygen species (ROS)-mediated therapeutics. Metallothionein-2 (MT-2), an intracellular cysteine-rich protein renowned for its potent antioxidant properties, is intricately involved in tumor development and correlates with a poor prognosis. Consequently, MT-2 emerges as a promising target for tumor therapy. Herein, we present the development of copper-doped carbon dots (Cu-CDs) to target MT-2 to compromise the delicate antioxidant reserves in tumor cells. These Cu-CDs with high tumor accumulation and prolonged body retention can effectively suppress tumor growth by inducing oxidative stress. Transcriptome sequencing unveils a significant decrease in MT-2 expression within the in vivo tumor samples. Further mechanical investigations demonstrate that the antitumor effect of Cu-CDs is intricately linked to apolipoprotein E (ApoE)-mediated downregulation of MT-2 expression and the collapse of the antioxidant system. The robust antitumor efficacy of Cu-CDs provides invaluable insights into developing MT-2-targeted nanomedicine for cancer therapies.

Keywords: antioxidant reserves; antitumor therapy; copper-doped carbon dots; metallothionein-2; oxidative stress.

MeSH terms

  • Animals
  • Antineoplastic Agents / chemistry
  • Antineoplastic Agents / pharmacology
  • Antioxidants* / chemistry
  • Antioxidants* / pharmacology
  • Carbon* / chemistry
  • Carbon* / pharmacology
  • Cell Line, Tumor
  • Copper* / chemistry
  • Copper* / pharmacology
  • Humans
  • Metallothionein* / genetics
  • Metallothionein* / metabolism
  • Mice
  • Neoplasms / drug therapy
  • Neoplasms / metabolism
  • Oxidative Stress / drug effects
  • Quantum Dots* / chemistry
  • Quantum Dots* / therapeutic use
  • Reactive Oxygen Species / metabolism

Substances

  • Metallothionein
  • Copper
  • Carbon
  • Antioxidants
  • Reactive Oxygen Species
  • Antineoplastic Agents
  • MT2A protein, human