Nanoparticle Strategy Utilizes Tumors’ Copper for Cancer Treatment

Researchers from Guizhou Medical University have developed a new strategy that uses nanoparticles to leverage the copper supply within tumors to induce cancer cell death. This research, published in Biomedical Analysis, investigates cuproptosis, a cell death process triggered by copper that disrupts cancer cell survival.

Previous approaches to cuproptosis centered on introducing external copper, raising concerns about toxicity to healthy tissues. This new system mitigates the risk by employing a copper-binding agent that targets cancer cells and utilizes the copper already inside tumors.

The researchers have created biodegradable nanoparticles using PLGA-PEG, a material known for its safety profile. They enhanced these nanoparticles with iRGD, a peptide aiding in the targeting of cancer cells. The nanoparticles are loaded with N,N,N′,N′-tetrakis(2-pyridylmethyl)ethylenediamine (TPEN), a metal ion-binding compound.

This formulation, TPEN@1%-iPPN, specifically delivers TPEN to tumor cells. Lab tests revealed the nanoparticles are approximately 80 nanometers in size, maintaining stability in mimicked bloodstream conditions, and releasing TPEN gradually over 72 hours for sustained tumor exposure.

Studies using 4T1 breast cancer cells showed that the nanoparticles with iRGD were more successful in targeting cancer cells than those without. A 1% iRGD modification achieved optimal targeting and stability.

The team assessed the impact on both cancer and normal cells. The targeted nanoparticles showed greater toxicity towards 4T1 breast cancer cells and caused less harm to normal human endothelial cells as compared to untargeted TPEN.

Dr. Ying Chen, a corresponding author, noted that mobilizing endogenous copper can enhance selectivity and minimize side effects typically associated with metal-based therapies. She expressed hope that their proof-of-concept will inspire further research in cuproptosis-based treatments.

Despite its potential benefits, significant challenges remain. Dr. Harshad Kulkarni from BAMF Health highlighted the scientific promise in exploiting cancer cells’ metabolic vulnerability through copper. He emphasized the importance of proving treatment safety, determining responsive cancer types, and identifying effectiveness indicators.

He flagged tumor selectivity as a central challenge since copper is crucial for normal cell functions; hence, altering copper levels could result in toxicity. Future studies should investigate side effects on major organs and cancer cells’ ability to adapt. This strategy might extend beyond breast cancer, contingent on each tumor’s unique characteristics.

Continued research will be crucial to transforming these laboratory findings into viable patient therapies.