Multifunctional Phase-Transition Nanoparticles for Effective Targeted Sonodynamic-Gene Therapy Against Thyroid Papillary Carcinoma.

Introduction: In order to diagnose and treat papillary thyroid carcinoma (PTC) accurately, phase-transition nanoparticles, P@IP-miRNA (PFP@IR780/PLGA-bPEI-miRNA338-3p), was engineered. The nanoparticles (NPs) can target the tumor cells, realize the multimodal imaging, and provide sonodynamic-gene therapy for PTC. Methods: P@IP-miRNA NPs were synthesized through double emulsification method, and miRNA338-3p was attached to the surface of the NPs by electrostatic adsorption. The characterization of NPs was detected to screen out qualified nanoparticles. In vitro, laser confocal microscopy and flow cytometry were used to detect the targeting and subcellular localization of NPs. Western blot, qRT-PCR, and immunofluorescence were used to detect the ability to transfect miRNA. CCK8 kit, laser confocal microscopy and flow cytometry were used to detect the inhibition on TPC-1 cells. In vivo experiments were performed based on tumor-bearing nude mice. The efficacy of combined treatment by NPs was comprehensively evaluated, and the multimodal imaging ability of NPs in vivo and in vitro was detected. Results: P@IP-miRNA NPs were successfully synthesized which have spherical shape, uniform size, good dispersion and positive potential. The encapsulation rate of IR780 was (82.58±3.92) %, the drug loading rate was (6.60±0.32) %, and the adsorption capacity of miRNA338-3p was 41.78 μg/mg. NPs have excellent tumor targeting ability, miRNA transfection ability, ROS production ability and multimodal imaging ability in vivo and in vitro. The antitumor effect of combined treatment group was the best, and the efficacy was better than that of single factor treatment group, and the difference was statistically significant. Conclusion: P@IP-miRNA NPs can realize multimodal imaging and sonodynamic-gene therapy, providing a new idea for accurate diagnosis and treatment of PTC.