Current nanodrug-based cancer therapy is susceptible to the problems of rapid clearance from circulation and limited therapeutic efficacy. Herein, we report a magnetically targeted and photothermal-triggered drug release nanotheranostics system based on superparamagnetic iron oxide (Fe3O4), IR780, doxorubicin (DOX), and perfluoropentane (PFP) entrapped poly-lactide-co-glycolide (PLGA) nanoparticles (IR780/Fe3O4@PLGA/PFP/DOX NPs) for triple-modal imaging-guided synergistic therapy of breast cancer. In this work, IR780 and Fe3O4 convert light into heat, which triggers DOX release from IR780/Fe3O4@PLGA/PFP/DOX NPs and a phase-shift thermoelastic expansion of PFP; this procedure further accelerates the DOX release and tissue extrusion deformation. Fe3O4 NPs also serve as the target moiety by an external magnet directed to the tumor. Specifically, the IR780/Fe3O4@PLGA/PFP/DOX NPs can be used for triple-modal imaging, including near infrared fluorescence, magnetic resonance, and ultrasound. Furthermore, the antitumor therapy studies reveal the extraordinary performance of IR780/Fe3O4@PLGA/PFP/DOX NPs in magnetically targeted synergistic chemo-photothermal therapy of cancer. Therefore, the multifunctional IR780/Fe3O4@PLGA/PFP/DOX NPs guided by the magnetic field show a great potential for cancer theranostics.

Background Although photothermal therapy (PTT) and photodynamics therapy (PDT) have both made excellent progress in tumor therapy, the effectiveness of using PTT or PDT alone is dissatisfactory due to the limitations of the penetration depth in PTT and the hypoxic microenvironment of tumors for PDT. Combination phototherapy has currently become a burgeoning cancer treatment. Methods and Materials In this work, a mitochondria-targeting liquid perfluorocarbon (PFC)-based oxygen delivery system was developed for the synergistic PDT/photothermal therapy (PTT) of cancer through image guiding. Results Importantly, these nanoparticles (NPs) can effectively and accurately accumulate in the target tumor via the enhanced permeability and retention (EPR) effect. Conclusion This approach offers a novel technique to achieve outstanding antitumor efficacy by an unprecedented design with tumor mitochondria targeting, oxygen delivery, and synergistic PDT/PTT with dual-imaging guidance.

Background Traditional nanoparticle-based drug delivery systems suffer from several limitations, such as easy clearance from blood and inaccurate targeting. Materials and Methods Here, we developed platelet membrane-coated nanoparticles (PM-NPs) to improve the precise delivery of drugs to tumor sites and enable a more efficient photothermal therapy (PTT) treatment. Results Mimicking the natural platelet membrane, nanoparticles containing drugs and photothermal agents were not recognized and cleared by the immune system; they could circulate in the blood for a long time and accumulate more efficiently at the tumor site, thus releasing more antitumor drugs and achieving better PTT effects. It is worth mentioning that, in this study, we found that tumors in mice treated with the platelet-mimicking nanoparticles were completely eliminated without recurrence during the observation period (up to 18 days). Conclusion This study provides a new strategy to design delivery systems of drugs or photothermal agents, whether in biotherapy or other fields.

Modulation of hypoxia is an essential factor for enhancing the effects of antitumor therapies, especially sonodynamic therapy and chemotherapy. To improve the efficacy of combination therapy by reversing the hypoxic tumor microenvironment, we developed shell-core structured PPID-NPs, which were designed with a polymer shell onto the sonosensitizer and a chemotherapeutic drug were loaded and a perfluorocarbon core loaded with oxygen. The perfluorocarbon core provides sufficient oxygen not only for causing the sonosensitizer to produce more singlet oxygen to induce cell apoptosis but also for reducing drug resistance to enhance therapeutic efficacy. Furthermore, the release of chemotherapeutic drugs at the tumor site can be controlled. Thus, PPID-NPs can efficiently inhibit the growth of breast cancer by synergistic therapy under ultrasound exposure. We believe that our oxygen-sufficient nanoplatform could be an ideal therapeutic system for hypoxic tumors.