Latest Nanoparticles to Modulate Hypoxic Microenvironment in Photodynamic Therapy of Cervical Cancer: A Review of In Vivo Studies.

Photodynamic therapy (PDT) is a promising, minimally invasive treatment for cervical cancer, but its efficacy is significantly limited by hypoxia-oxygen deficiency in the tumour microenvironment. The aim of this study was to present strategies to counteract hypoxia in PDT using the latest nanotechnologies. Based on a review of the literature available in PubMed/MEDLINE, Scopus, and Web of Science databases, covering the period from January 2024 to March 2025, nine original in vivo studies were identified that investigated the use of nanoparticle-based strategies to overcome hypoxia and enhance the efficacy of PDT in cervical cancer. A variety of approaches to improve tumour oxygenation are described, including the catalytic decomposition of hydrogen peroxide (HO) with manganese oxide (MnO), the use of bimetallic nanozymes (e.g., AuPt), and FeOOH structures and oxygen storage and control systems (e.g., endoperoxides). Strategies to reduce oxygen consumption by cancer cells, such as nitric oxide (NO) release or inhibition of mitochondrial oxidative phosphorylation, are also discussed. The review shows that appropriately designed nanoparticles can effectively counteract hypoxia, enhancing the efficacy of PDT by intensifying reactive oxygen species (ROS) generation and modulating HIF-1α factor expression. The strategies presented here have the potential to significantly improve the efficacy of photodynamic therapy in the treatment of cervical cancer, especially under conditions of limited oxygen availability.