OXPHOS-targeted nanoparticles for boosting photodynamic therapy against hypoxia tumor

Area of Science:

• Biomedical Engineering
• Nanotechnology
• Cancer Therapy

Background:

• Tumor hypoxia limits photodynamic therapy (PDT) efficacy due to insufficient oxygen for reactive oxygen species (ROS) generation.
• Oxidative phosphorylation (OXPHOS) is a key oxygen-consuming process in tumor cells.
• Mitochondria are crucial targets for ROS-induced damage and ATP production.

Purpose of the Study:

• To develop a nanoplatform that alleviates tumor hypoxia and enhances PDT efficacy.
• To investigate the role of an OXPHOS inhibitor in improving oxygen availability for ROS production.
• To evaluate the mitochondrial targeting and antitumor effects of the novel nanoplatform.

Main Methods:

• Fabrication of triphenylphosphine (TPP)-modified nanocarriers encapsulating IR780 (photosensitizer) and atovaquone (ATO, OXPHOS inhibitor) in mPEG-PLGA.
• Utilizing TPP for targeted delivery of ATO to mitochondria, inhibiting OXPHOS and reducing oxygen consumption.
• Employing IR780 within mitochondria to enhance ROS generation and induce apoptosis upon light activation.

Main Results:

• The nanoplatform (TNPs/IA) demonstrated precise subcellular localization in mitochondria.
• Inhibition of OXPHOS by ATO led to decreased ATP production and mitochondrial damage.
• TNPs/IA significantly enhanced antitumor efficacy in a HeLa subcutaneous xenograft model through oxygen-augmented PDT.

Conclusions:

• The developed nanoplatform effectively alleviates tumor hypoxia by inhibiting mitochondrial OXPHOS.
• Targeting mitochondria with both a photosensitizer and an OXPHOS inhibitor offers a promising strategy for enhanced PDT.
• This approach represents a potential advancement in photodynamic tumor eradication.