As a non-invasive therapeutic, radiotherapy (RT) has been extensively used for solid tumor treatment. However, intratumoral hypoxia leads to severe RT resistance or failure. Moreover, damage from RT to normal tissues limits the application of high doses of radiation to eliminate cancer cells. Therefore, simultaneously improving the curative efficacy while minimizing the side effects of RT is in pressing need. Hence, the purpose of this study is to use oxygen-based microbubbles (O₂ @MBs) combined with ultrasound (US) targeting microbubble destruction (UTMD) technology to overcome hypoxia prior to RT, evaluate the effects of O₂ @MBs on contrast-enhanced ultrasound (CEUS) imaging enhancement, investigate the optimum delivery route of O₂ @MBs, and evaluate the therapeutic efficacy. In this study, O₂ @MBs were injected intravenously or locally and the distribution of O₂ @MBs in tumors or regions surrounding the tumors are compared by US imaging. The hypoxic status of tumors and their sensitivity to RT were investigated. Our findings suggest that O₂ @MBs combined with UTMD can significantly enhance the effects of RT. In addition, the in vivo biosafety assay demonstrates good biocompatibility, indicating great potential for clinical translation.

中文翻译：

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超声介导的氧气输送，借助超声成像指导增强放疗。

作为非侵入性疗法，放射疗法（RT）已广泛用于实体瘤治疗。但是，肿瘤内缺氧会导致严重的RT抵抗或衰竭。此外，从RT到正常组织的损伤限制了高剂量辐射的应用以消除癌细胞。因此，迫切需要同时提高治疗效果同时最小化RT的副作用。因此，本研究的目的是结合氧基微泡（O 2 @MBs）和超声（US）靶向微泡破坏（UTMD）技术克服RT前的缺氧，评估O2 @MBs对增强造影剂的影响超声（CEUS）成像增强，研究O2 @MBs的最佳递送途径，并评估治疗效果。在这个研究中，O 2 @MB静脉内或局部注射，并通过US成像比较O 2 @MBs在肿瘤或肿瘤周围区域中的分布。研究了肿瘤的低氧状态及其对RT的敏感性。我们的发现表明O2 @MBs与UTMD结合可以显着增强RT的作用。另外，体内生物安全性测定法显示出良好的生物相容性，表明临床翻译的巨大潜力。