Magnetic mesoporous embolic microspheres in transcatheter arterial chemoembolization for liver cancer.

Transcatheter arterial chemoembolization (TACE) is the main treatment for liver cancer. Although many embolic agents have been exploited in TACE, embolic agents combining embolization, drug loading, and imaging properties have not yet been constructed. Herein, we report a new magnetic mesoporous embolic microsphere that can simultaneously be loaded with doxorubicin (Dox), block vessels, and be observed by magnetic resonance imaging (MRI). The microspheres were prepared by decorating magnetic polystyrene/Fe3O4 particles with mesoporous organosilica microparticles (denoted as PS/Fe3O4@MONs). The PS/Fe3O4@MONs were uniformly spherical and large (50 µm), with a high specific surface area, uniform mesopores, and a Dox loading capacity of 460.8 µg mg-1. Dox-loaded PS/Fe3O4@MONs (PS/Fe3O4@MON@Dox) effectively inhibited liver cancer cell growth. A VX2 rabbit liver tumor model was constructed to study the efficacy of TACE with PS/Fe3O4@MON@Dox. In vivo, PS/Fe3O4@MON@Dox could be smoothly delivered through an arterial catheter to achieve chemoembolization. Moreover, PS/Fe3O4@MON@Dox and residual tumor parenchyma could be distinguished on MRI, which is of great significance for evaluating the efficacy of TACE. Histopathology showed that PS/Fe3O4@MON@Dox could be deposited in the tumor vessels, completely blocking the blood supply. Overall, PS/Fe3O4@MON@Dox showed good drug loading, embolization and imaging performance as well as potential for use in TACE. STATEMENT OF SIGNIFICANCE: Transcatheter arterial chemoembolization (TACE) is the main treatment for liver cancer. Although many embolic agents have been exploited in TACE, embolic agents combining embolization, drug-loading, and imaging properties have not yet been constructed. In this work, we prepared magnetic mesoporous microspheres as a new embolic agent that can simultaneously load doxorubicin (Dox), block blood vessels and enable magnetic resonance imaging. Overall, this new embolic microsphere-mediated TACE strategy for liver cancer showed good therapeutic effects, and the PS/Fe3O4@MON@Dox embolic microspheres provide a new avenue for improving the efficacy of TACE for liver cancer and postoperative evaluation.