School of Biomedical Engineering and Health Sciences, Drexel University, Philadelphia, Pennsylvania, USA; Department of Radiology, Thomas Jefferson University, Philadelphia, Pennsylvania, USA.
Department of Radiology, Thomas Jefferson University, Philadelphia, Pennsylvania, USA.
Ultrasound Med Biol. 2021 Jun;47(6):1465-1474. doi: 10.1016/j.ultrasmedbio.2021.01.032. Epub 2021 Feb 27.
Radiation therapy (RT) causes DNA damage through ionization, leading to double-strand breaks. In addition, it generates reactive oxygen species (ROS), which are toxic to tumor cells and the vasculature. However, hypoxic regions in the tumor have been shown to not only decrease treatment response but also increase the likelihood of recurrence and metastasis. Ultrasound-sensitive micro-bubbles are emerging as a useful diagnostic and therapeutic tool within RT. Contrast-enhanced ultrasound (CEUS) has shown great promise in early prediction of tumor response to RT. Ultrasound-triggered micro-bubble cavitation has also been shown to induce bio-effects that can sensitize angiogenic tumor vessels to RT. Additionally, ultrasound can trigger the release of drugs from micro-bubble carriers via localized micro-bubble destruction. This approach has numerous applications in RT, including targeted oxygen delivery before radiotherapy. Furthermore, micro-bubbles can be used to locally create ROS without radiation. Sonodynamic therapy uses focused ultrasound and a sonosensitizer to selectively produce ROS in the tumor region and has been explored as a treatment option for cancer. This review summarizes emerging applications of ultrasound contrast agents in RT and ROS augmentation.
放射治疗（RT）通过电离导致 DNA 损伤，从而产生双链断裂。此外，它还会产生活性氧（ROS），对肿瘤细胞和血管系统都有毒性。然而，肿瘤中的缺氧区域不仅会降低治疗反应，还会增加复发和转移的可能性。超声敏感微泡在 RT 中作为一种有用的诊断和治疗工具正在崭露头角。对比增强超声（CEUS）在早期预测肿瘤对 RT 的反应方面显示出巨大的潜力。超声触发的微泡空化也已被证明可以诱导生物效应，使血管生成的肿瘤血管对 RT 敏感。此外，超声可以通过局部微泡破坏从微泡载体中触发药物释放。这种方法在 RT 中有许多应用，包括放疗前的靶向氧输送。此外，微泡可用于在不辐射的情况下局部产生 ROS。声动力学疗法使用聚焦超声和声敏剂在肿瘤区域选择性地产生 ROS，已被探索作为癌症的治疗选择。本综述总结了超声对比剂在 RT 和 ROS 增强中的新应用。
