A carrier-free tri-component nanoreactor for multi-pronged synergistic cancer therapy

Non-invasive therapies such as photodynamic therapy (PDT) and chemodynamic therapy (CDT) have received wide attention due to their low toxicity and side effects, but their efficacy is limited by the tumor microenvironment (TME), and monotherapy cannot achieve satisfactory efficacy. In this work, a multifunctional nanoparticle co-assembled from oleanolic acid (OA), chlorin e6 (Ce6), and hemin was developed. The as-constructed nanoparticle named OCH with diameters of around 130 nm possessed good biostability, pH/GSH dual-responsive drug release properties, and remarkable cellular internalization and tumor accumulation capabilities. OCH exhibited prominent catalytic activities to generate •OH, deplete GSH, and produce O2 to overcome the hypoxia TME, thus potentiating the photodynamic and chemodynamic effect. In addition, OCH can induce the occurrence of ferroptosis in both ferroptosis-sensitive and ferroptosis-resistant cancer cells. The multi-pronged effects of OCH including hypoxia alleviation, GSH depletion, ferroptosis induction, CDT, and PDT effects jointly facilitate excellent anticancer effects in vitro and in vivo. Hence, this work will advance the development of safe and effective clinically transformable nanomedicine by employing clinically-applied agents to form drug combinations for efficient multi-pronged combination cancer therapy.