Metal peroxides for cancer treatment

In recent years, metal peroxide (MO₂) such as CaO₂ has received more and more attention in cancer treatment. MO₂ is readily decompose to release metal ions and hydrogen peroxide in the acidic tumor microenvironment (TME), resulting metal ions overloading, decreased acidity and elevated oxidative stress in TME. All of these changes making MO₂ an excellent tumor therapeutic agent. Moreover, by combining MO₂ with photosensitizers, enzymes or Fenton reagents, MO₂ can assist and promote various tumor therapies such as photodynamic therapy and chemodynamic therapy. In this review, the synthesis and modification methods of MO₂ are introduced, and the representative studies of MO₂-based tumor monotherapy and combination therapy are discussed in detail. Finally, the current challenges and prospects of MO₂ in the field of tumor therapy are emphasized to promote the development of MO₂-based cancer treatment.