Ultrasound-triggered release of sinoporphyrin sodium from liposome-microbubble complexes and its enhanced sonodynamic toxicity in breast cancer

Applying ultrasound (US) to drug delivery and disease therapy is important work. Sonodynamic therapy (SDT)—a comprehensive therapy using US and a sonosensitizer—exhibits antineoplastic activity in many tumors. In this study, we investigated the feasibility of using a new sonosensitizer (sinoporphyrin sodium, DVDMS) loaded into liposome–microbubble complexes (DLMBs) as a possible candidate to enhance SDT against breast cancer. DLMBs were synthesized via the biotin–avidin linkage and confirmed to have good US response. US-induced cavitation played a key role to trigger a boosted payload release from DLMBs and improve the cellular uptake and intratumoral diffusion of DVDMS to realize better SDT effect. The combination of DLMBs and US treatment resulted in significant changes to cell morphology, mitochondria damage, and cell apoptosis in vitro. In vivo, the combined treatment markedly inhibited tumor growth, which appeared to result from increased apoptosis and reduced proliferation activity. The significant increase in the antitumor effect of DLMBs plus US suggests their potential use as a new approach to promote the killing activity of SDT against breast cancer.