Preparation of polydopamine-based concave nanoparticles and mild photothermal-anti-inflammatory combination therapy for breast cancer guided by magnetic resonance imaging

[Display omitted] •A multifunctional photothermal theranostic nanoplatform (B-MPDA/CQ/ASP@MnO2-HA NPs) was prepared.•The nanoplatform enhances the efficacy of mild photothermal therapy through autophagy inhibition.•The intracellular and in vivo treatment effects and targeting capabilities of the nanoplatform were illustrated.•High-spatial resolution, real-time magnetic resonance imaging of solid tumor was realized.•The in vivo anti-inflammatory effect of the nanoplatform was confirmed. Photothermal therapy (PTT) has been widely investigated as a regimen for superficial tumors. However, conventional PTT strategies usually require photothermal temperatures above 50 °C to achieve significant therapeutic efficacy, which in effect would lead to injury to adjacent normal tissues and meanwhile, the heat generated by the photothermal effect would induce inflammation owing to the damage to cytoplasmic components. In order to reduce the toxicity of photothermal therapy and increase the efficiency of photothermal tumor destruction, novel strategies are prerequisite for targeted regimen and surveillance of photothermal therapy in real time. In this paper, we reported a concave mesoporous polydopamine-targeting nanotherapeutic agent. We employed B-MPDA as the carrier and encapsulated CQ and ASP to yield B-MPDA/CQ/ASP which was loaded with autophagy inhibitors and anti-inflammatory agents and coated uniformly with MnO2 Nanosheet. With HA functionalizing MnO2 Nanosheet, B-MPDA/CQ/ASP@MnO2-HA was constituted. The yielded nanoparticles were identified to be advantageous for good biocompatibility, potent targeting and low toxicity. In anti-tumor regimens, the nanoparticles can be applied to hyaluronic acid targeting, mesoporous polydopamine thermotherapy, and autophagy inhibitor sensitization thermotherapy, and simultaneously eliminate the inflammatory effects induced by photothermal therapy. Furthermore, in combination with the anti-inflammatory effect of targeting tumor, this agent can effectively induce apoptosis of cancer cells and significantly improve the efficiency of mild photothermal killing of cancer cells, which provides insight into the development of nanoparticles and application to mild photothermal therapy in the clinical scenario.