Qiu Yi-Jie, Cao Jia-Ying, Liao Jing-Han, Duan Yi, Chen Sheng, Cheng Rui, Huang Yun-Lin, Lu Xiu-Yun, Cheng Juan, Wang Wen-Ping, Duan You-Rong, Dong Yi
Department of Ultrasound, Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 200092, PR China.
State Key Laboratory of Systems Medicine for Cancer, Shanghai Cancer Institute, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200032, PR China.
Acta Biomater. 2025 May 1;197:416-430. doi: 10.1016/j.actbio.2025.03.018. Epub 2025 Mar 13.
Ultrasound molecular imaging is an innovative imaging modality that combines ultrasound with molecular probes to observe live biological processes at the cellular and molecular levels. C-X-C chemokine receptor type 4 (CXCR4) is a specific target in liver tumors and plays a crucial role in promoting tumor growth, invasion, metastasis, and angiogenesis. This study pioneered the use of CXCR4-targeted ultrasound molecular imaging for visualized antitumor therapy and investigated the potential of CXCR4-targeted microbubbles (MBs) in sensitizing liver tumor treatment. CXCR4-targeted MBs demonstrated high ligands conjugation efficiency to vascular endothelial cells (99.77 ± 0.15 %) and significantly inhibited the migration and invasion of Hepa1-6 cells. Molecular CEUS imaging results indicated that the MBs carrying LFC131 peptides facilitated site-specific recognition in BALB/c mice bearing Hep G2 tumors. After the 2-week of chemotherapy, ultrasound molecular imaging signals were significantly reduced in liver cancer when using CXCR4-targeted MBs compared to the SonoVue group which were corroborated by quantitative immunohistochemical grading of CXCR4 expression. In liver cancer immunotherapy, the anti-PD-L1 mAb + CXCR4-targeted MBs group yielded a remarkable tumor inhibition rate (94.6 %) with increased CD8+ T-cell infiltration and decreased FOXP3+ regulatory T cells. Bulk RNA-seq analysis and animal experiment confirmed that anti-PD-L1 mAb combined with CXCR4-targeted MBs effectively induced a robust immune response in liver cancer. These findings establish a solid foundation for future molecular CEUS imaging applications and the development of sensitization strategies for liver cancer therapy. STATEMENT OF SIGNIFICANCE: Ultrasound molecular imaging plays a pivotal role in advancing precision medicine by optimizing tumor diagnosis and treatment. This study pioneers ultrasound molecular imaging in liver tumor therapy using CXCR4-targeted microbubbles (MBs) conjugated with LFC131 peptides. Achieving 99.77 % ligand binding efficiency, the CXCR4-targeted MBs group suppressed tumor migration and enabled precise molecular imaging validated by immunohistochemistry. Moreover, the integration of CXCR4-targeted MBs with anti-PD-L1 immunotherapy resulted in a remarkable tumor inhibition rate of 94.6 %, accompanied by increased CD8+ T cells and decreased FOXP3+ regulatory T cells. These findings underscore the dual role of CXCR4-targeted MBs in both imaging and enhancing chemotherapy/immunotherapy, establishing a foundational framework for the future advancement of molecular imaging-guided liver cancer treatment.
超声分子成像（Ultrasound molecular imaging）是一种创新的成像方式，它将超声与分子探针相结合，以在细胞和分子水平上观察活体生物过程。C-X-C趋化因子受体4（C-X-C chemokine receptor type 4，CXCR4）是肝肿瘤中的一个特定靶点，在促进肿瘤生长、侵袭、转移和血管生成中起关键作用。本研究率先将靶向CXCR4的超声分子成像用于可视化抗肿瘤治疗，并研究了靶向CXCR4的微泡（microbubbles，MBs）在增强肝肿瘤治疗敏感性方面的潜力。靶向CXCR4的微泡显示出与血管内皮细胞的高配体结合效率（99.77±0.15%），并显著抑制Hepa1-6细胞的迁移和侵袭。分子对比增强超声成像结果表明，携带LFC131肽的微泡在携带Hep G2肿瘤的BALB/c小鼠中促进了位点特异性识别。化疗2周后，与声诺维组相比，使用靶向CXCR4的微泡时肝癌的超声分子成像信号显著降低，这一点通过CXCR4表达的定量免疫组织化学分级得到了证实。在肝癌免疫治疗中，抗PD-L1单克隆抗体+靶向CXCR4的微泡组产生了显著的肿瘤抑制率（94.6%），同时CD8+T细胞浸润增加，FOXP3+调节性T细胞减少。批量RNA测序分析和动物实验证实，抗PD-L1单克隆抗体与靶向CXCR4的微泡联合使用可有效诱导肝癌中强大的免疫反应。这些发现为未来分子对比增强超声成像应用以及肝癌治疗增敏策略的开发奠定了坚实基础。重要性声明：超声分子成像通过优化肿瘤诊断和治疗在推进精准医学方面发挥着关键作用。本研究率先在肝肿瘤治疗中使用与LFC131肽偶联的靶向CXCR4的微泡进行超声分子成像。靶向CXCR4的微泡组实现了99.77%的配体结合效率，抑制了肿瘤迁移，并通过免疫组织化学验证了精确的分子成像。此外，靶向CXCR4的微泡与抗PD-L1免疫治疗相结合，产生了94.6%的显著肿瘤抑制率，同时CD8+T细胞增加，FOXP3+调节性T细胞减少。这些发现强调了靶向CXCR4的微泡在成像和增强化疗/免疫治疗方面的双重作用，为未来分子成像引导的肝癌治疗进展建立了基础框架。
