Recent advances in calcium peroxide nanomedicines for breast cancer treatment

As a typical solid tumor, breast cancer is characterized by a tumor microenvironment featuring hypoxia, acidosis, and highly reductive conditions. These factors contribute to treatment resistance (e.g., chemoresistance) through various mechanisms, thereby diminishing therapeutic efficacy. Calcium peroxide (CaO₂) can generate multiple bioactive molecules (metal ions, H₂O₂, O₂, and OH^-) in acidic or neutral environment, making it a promising biomaterial for cancer therapy. Recently, breast cancer has been extensively targeted using CaO₂ nanoparticles in both cellular and murine models. In this review, we first provide a summary of strategies employing CaO₂ nanomedicine-based breast cancer therapies, then discuss the obstacles and development directions of CaO₂ application in breast cancer therapy.