A multifunctional platform with metallacycle-based star polymers and gold nanorods for combinational photochemotherapy

Although platinum-based anticancer drugs have prevailed in traditional chemotherapy, the severe side effects and drug resistance hampered their clinical applications. Combinational therapies have exhibited promises in antitumor treatments. However, the integration of different anticancer modalities is often challenging because of the conflicts between maximal synergy of therapeutic effects and reduction of side effects. Here, we report a multifunctional platform composed of metallacycle-based star polymer and gold nanorods for synergistic photochemotherapy. We applied the Pt-based metallacycle-cored star polymers as both a photodynamic photosensitizer and a Pt-based anticancer drug. The gold nanorods play the dual role of photothermal converter and energy acceptor of fluorescence resonance energy transfer effect from the star polymers. The photothermal effect enhanced tumor permeability of reactive oxygen species and Pt-based drug molecules and the photodynamic effect destructed heat shock proteins to prevent the mechanism of cellular self-protection response to heat. This mutually beneficial strategy results in high therapeutic efficacy and negligible side effects verified by both in vitro and in vivo studies. This study offers a new avenue in designing a multifunctional platform for the synergy of different antitumor modalities.