Polydopamine-coated ferric oxide nanoparticles for R848 delivery for photothermal immunotherapy in breast cancer

Association of R848 and targeted ferric oxide nanoparticles coated with polydopamine to mediate photothermal immunotherapy for breast cancer therapy. [Display omitted] Breast cancer, which requires comprehensive multifunctional treatment strategies, is a major threat to the health of women. To develop multifunctional treatment strategies, we combined photothermal therapy (PTT) with immunotherapy in multifunctional nanoparticles for enhancing the anti-tumor efficacy. Fe3O4 nanoparticles coated with the polydopamine shell modified with polyethylene glycol and cyclic arginine-glycyl-aspartic peptide/anisamide (tNP) for loading the immune adjuvant resiquimod (R848) (R848@tNP) were developed in this research. R848@tNP had a round-like morphology with a mean diameter of 174.7 ± 3.8 nm, the zeta potential of −20.9 ± 0.9 mV, the drug loading rate of 9.2 ± 1.1 %, the encapsulation efficiency of 81.7 ± 3.2 %, high photothermal conversion efficiency and excellent magnetic properties in vitro. Furthermore, this research also explored the anticancer efficacy of nanoparticles against the breast cancer under the near-infrared (NIR) light (808 nm) in vitro and in vivo. R848@tNP-based NIR therapy effectively inhibited the proliferation of breast cancer cells. Moreover, R848@tNP mediated PTT significantly enhanced the maturation of dendritic cells in vitro. Additionally, R848@tNP enhances the anti-tumor effect and evoked an immune response under NIR in vivo. Furthermore, the biosafety of R848@tNP was fully investigated in this study. Collectively, these results clearly demonstrate that R848@tNP, with magnetic resonance imaging characteristics, is a potential therapeutic for breast cancer that combines PTT with the immunotherapy.