Nanosonosensitization by Using Copper–Cysteamine Nanoparticles Augmented Sonodynamic Cancer Treatment

Sonodynamic therapy (SDT), as a newly emerging and promising modality for cancer treatment, has been extensively investigated but with limited therapeutic outcome because of the absence of highly efficient sonosensitizer. Copper–cysteamine (Cu–Cy), as a new sensitizer, has been reported for oxidative therapy which can be activated with light, X-ray, or microwave. Herein, for the first time, Cu–Cy nanoparticles are reported as new sonosensitizers for SDT on breast cancer treatment. Upon exposure of Cu–Cy nanoparticles to ultrasound, a large quantity of reactive oxygen species (ROS) are generated for cancer cell destruction with a high SDT efficiency to induce cell apoptosis and necrosis as observed in vitro. In vivo animal studies show a significant inhibition of tumor growth for the xenografts of 4T1 cancer cells with the combination of 0.75 mg kg⁻¹ Cu–Cy and ultrasound. Overall, the preliminary results show that Cu–Cy nanoparticles can significantly augment the levels of ROS induced by ultrasound, demonstrating Cu–Cy is a new kind of efficient sonosensitzers for SDT applications. Such therapeutic platform by integrating a noninvasive, highly safe, deep-penetration ultrasound modality. and quickly developed versatile nanosensitizers for tumor eradication will facilitate SDT future clinical translation.