Dual-targeted and pH-sensitive Doxorubicin Prodrug-Microbubble Complex with Ultrasound for Tumor Treatment.
Dual-targeted and pH-sensitive Doxorubicin Prodrug-Microbubble Complex with Ultrasound for Tumor Treatment.
复制标题
双靶点、pH 敏感的阿霉素前药-微泡复合物与超声治疗肿瘤
作者：
Luo W;Wen G;Yang L;Tang J;Wang J;Wang J;Zhang S;Zhang L;Ma F;Xiao L;Wang Y;Li Y
在这项研究中，我们研究了双靶向pH敏感的阿霉素前药微泡复合物（DPMC）在超声（US）辅助抗肿瘤治疗中的潜力。多柔比星前药（DP）由琥珀酰化肝素载体通过腙键与多柔比星（DOX）偶联组成，并用双靶向配体叶酸和cRGD肽修饰。通过亲和素-生物素结合产生的微泡（MB）和DP的组合促进了细胞内蓄积，并通过超声空化和声孔作用辅助提高了治疗效率。DP的聚集体具有不均匀的粒径分布（平均粒径：149.6±29.8 nm和1036.2±38.8 nm，PDI：1.0），而DPMC具有均匀的分布（平均粒径：5.804±2.1 μm），有利于其用于药物递送。值得注意的是，在US暴露后，DPMC被破坏并且聚集的DP分散成均匀的小尺寸纳米颗粒（平均直径：128.6±42.3 nm，PDI：0.21）。超声照射后，DPMC可通过αvβ3介导的识别作用靶向肿瘤区域的血管内皮细胞，并通过识别叶酸受体（FR）介导的特异性结合肿瘤细胞。体外实验表明，与游离DOX和DP相比，含US的DPMC对乳腺癌MCF-7细胞具有更高的肿瘤特异性和杀伤能力。此外，使用体内荧光和超声分子成像检测到DPMC与US对肿瘤组织的显著积累和特异性，表明其具有整合肿瘤成像和治疗的潜力。特别是，通过诱导凋亡，抑制细胞增殖和拮抗血管生成，DPMC与US产生更高的肿瘤抑制率比DOX或DPMC没有US在MCF-7异种移植瘤荷瘤小鼠，而不引起明显的体重下降。我们的策略提供了一个有效的平台，用于将大尺寸或聚集的颗粒递送到肿瘤部位，从而扩展其在体内的治疗应用。
In this study, we investigated the potential of a dual-targeted pH-sensitive doxorubicin prodrug-microbubble complex (DPMC) in ultrasound (US)-assisted antitumor therapy. The doxorubicin prodrug (DP) consists of a succinylated-heparin carrier conjugated with doxorubicin (DOX) via hydrazone linkage and decorated with dual targeting ligands, folate and cRGD peptide. Combination of microbubble (MB) and DP, generated via avidin-biotin binding, promoted intracellular accumulation and improved therapeutic efficiency assisted by US cavitation and sonoporation. Aggregates of prepared DP were observed with an inhomogeneous size distribution (average diameters: 149.6±29.8 nm and 1036.2±38.8 nm, PDI: 1.0) while DPMC exhibited a uniform distribution (average diameter: 5.804±2.1 μm), facilitating its usage for drug delivery. Notably, upon US exposure, DPMC was disrupted and aggregated DP dispersed into homogeneous small-sized nanoparticles (average diameter: 128.6±42.3 nm, PDI: 0.21). DPMC could target to angiogenic endothelial cells in tumor region via αvβ3-mediated recognition and subsequently facilitate its specific binding to tumor cells mediated via recognition of folate receptor (FR) after US exposure. In vitro experiments showed higher tumor specificity and killing ability of DPMC with US than free DOX and DP for breast cancer MCF-7 cells. Furthermore, significant accumulation and specificity for tumor tissues of DPMC with US were detected using in vivo fluorescence and ultrasound molecular imaging, indicating its potential to integrate tumor imaging and therapy. In particular, through inducing apoptosis, inhibiting cell proliferation and antagonizing angiogenesis, DPMC with US produced higher tumor inhibition rates than DOX or DPMC without US in MCF-7 xenograft tumor-bearing mice while inducing no obvious body weight loss. Our strategy provides an effective platform for the delivery of large-sized or aggregated particles to tumor sites, thereby extending their therapeutic applications in vivo.