Enhancement of focused ultrasound with microbubbles on the treatments of anticancer nanodrug in mouse tumors

Ultrasound sonication with microbubbles (MBs) has the potential to enhance the delivery of nanoparticles into the sonicated tumors. In this study, we investigated the feasibility of focused ultrasound (FUS) sonication with MBs to improve nanodrug delivery and tumor treatment. Tumor-bearing mice were first injected with MBs (SonoVue) intravenously, were then sonicated at the tumors with FUS sonication, and were finally injected with the PEGylated liposomal doxorubicin (DOX). The accumulation of DOX in tumors with time, the tumor growth responses for initial treated tumor size and DOX dosage, and the response for an additional sonication after DOX injection were studied. The results demonstrate that FUS sonication with MBs can significantly enhance DOX accumulation in the sonicated tumor at 24 hours after treatment. A significant hindrance to tumor growth is achieved for a small tumor with a low dose, whereas large tumors require a higher dose. From the Clinical Editor: In this novel research study, focused ultrasound created microbubbles were utilized to enhance the delivery of PEGylated liposomal doxorubicin in a murine tumor model, demonstrating superior drug delivery compared to other methods. Focused ultrasound-based techniques are increasingly studied in cancer research, and this new observation will likely lead to additional investigations of different tumor lines, penetration depths and delivery vehicles.