# Simultaneous Down-Regulation of Intracellular hTERT and GPX4 mRNA Using MnO2-Nanosheet Probes to Induce Cancer Cell Death

## TL;DR

A new nanosheet probe simultaneously targets two cancer-related genes to enhance cancer cell death through multiple pathways.

## Contribution

A MnO₂ nanosheet probe co-delivers antisense oligonucleotides to down-regulate hTERT and GPX4, inducing apoptosis and ferroptosis in cancer cells.

## Key findings

- The MnO₂-NS probe significantly suppressed cancer cell proliferation compared to single-target controls.
- Molecular analyses showed reduced hTERT and GPX4 expression, GSH depletion, and increased lipid peroxidation.
- The probe promotes dual cell death pathways through synergistic gene silencing and ROS accumulation.

## Abstract

Cancer remains a leading global cause of death, with conventional treatments often limited by toxicity and recurrence. Recent advances in gene therapy and nanodrug delivery offer new avenues for precision oncology. Human telomerase reverse transcriptase (hTERT) and glutathione peroxidase 4 (GPX4) are overexpressed in many cancers and linked to apoptosis and ferroptosis, respectively. Here, we developed a manganese dioxide nanosheet (MnO2-NS) probe co-loaded with antisense oligonucleotides targeting hTERT and GPX4 mRNA to synergistically down-regulate both genes and induce dual cell death pathways. The probe, assembled via adsorption of fluorescently labeled antisense strands, showed controllable release in the presence of glutathione (GSH). Cellular uptake and antisense release were confirmed in multiple cancer cell lines. The MnO2-NS probe significantly suppressed cell proliferation, outperforming single-target or carrier-only controls. Molecular analyses confirmed reduced hTERT and GPX4 expression, along with GSH depletion, ROS accumulation, and elevated lipid peroxidation—collectively promoting enhanced cancer cell death. In summary, this MnO2-NS-based co-delivery system enables synergistic gene silencing and GSH depletion, enhancing antitumor efficacy and providing a promising strategy for multifunctional nanotherapy.