Jiang Zhongji, Zhang Jin, Jin Jiali, Zhang Xun, Kadeerhan Gaohaer, Guo Hong, Wang Dongwen
Department of Biology, School of Medicine, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, People's Republic of China.
Department of Urology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital & Shenzhen Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Shenzhen, Guangdong, 518116, People's Republic of China.
Int J Nanomedicine. 2025 Aug 9;20:9807-9823. doi: 10.2147/IJN.S532080. eCollection 2025.
Prostate-specific membrane antigen (PSMA) is a well-established biomarker overexpressed in prostate cancer (PCa). However, existing PSMA-targeted imaging probes suffer from radiation exposure, limited tissue penetration, and inadequate intraoperative performance. To overcome these challenges, we developed a novel near-infrared-II (NIR-II) fluorescent nanoprobe for both in vivo and ex vivo imaging of PCa.
An organic semiconducting polymer (OSP) with strong NIR-II fluorescence and excellent photostability was self-assembled into nanoparticles (NPs) using DSPE-PEG-Mal. These OSP NPs were then conjugated with ACUPA-SH, (S)-2-[3-((S)-5-amino-1-carboxypentyl)ureido]pentanedioic acid, a thiol-modified glutamate-urea-lysine derivative that specifically targets PSMA, via a maleimide-thiol click reaction to form PSMA-OSP NPs. The probe's targeting specificity was assessed using PSMA positive and negative cell lines under NIR-II imaging. For in vivo evaluation, subcutaneous xenograft tumors were established in BALB/c nude mice. Animals were randomly assigned to PSMA-OSP NP, blocking (ACUPA pre-injection), and control (OSP NPs) groups (n = 3 per group). Ex vivo tumor slice imaging was performed on fresh tissue sections. Biosafety was evaluated in healthy mice (n=5) through hematological, biochemical, and histopathological analyses.
PSMA-OSP NPs exhibited excellent optical properties in the NIR-II window, including high photostability, negligible autofluorescence, and deep tissue penetration. In vitro assays confirmed selective binding to PSMA-positive cells, while in vivo imaging demonstrated sustained tumor accumulation with a peak TBR of 7.40 ± 1.28 at 48 h post-injection. This performance significantly surpassed OTL78 and Cy-KUE-OA, enabling flexible surgical planning and real-time intraoperative guidance. In ex vivo tissue imaging, PSMA-OSP NPs provided high-contrast tumor delineation without systemic administration. Biosafety evaluations revealed no significant systemic toxicity, and biodistribution analysis indicated hepatic metabolism and biliary clearance.
PSMA-OSP NPs are a promising NIR-II fluorescent probe with excellent tumor specificity, deep tissue imaging capability, and good biocompatibility, supporting their application in fluorescence-guided surgery and ex vivo tumor evaluation.
前列腺特异性膜抗原（PSMA）是一种在前列腺癌（PCa）中高表达的成熟生物标志物。然而，现有的靶向PSMA的成像探针存在辐射暴露、组织穿透有限和术中性能不足等问题。为了克服这些挑战，我们开发了一种新型的近红外二区（NIR-II）荧光纳米探针，用于PCa的体内和体外成像。
使用DSPE-PEG-Mal将具有强NIR-II荧光和优异光稳定性的有机半导体聚合物（OSP）自组装成纳米颗粒（NPs）。然后，通过马来酰亚胺-硫醇点击反应，将这些OSP NPs与ACUPA-SH（一种硫醇修饰的谷氨酸-脲-赖氨酸衍生物，特异性靶向PSMA）偶联，形成PSMA-OSP NPs。在NIR-II成像下，使用PSMA阳性和阴性细胞系评估探针的靶向特异性。为了进行体内评估，在BALB/c裸鼠中建立皮下异种移植肿瘤。将动物随机分为PSMA-OSP NP组、阻断组（预先注射ACUPA）和对照组（OSP NPs）（每组n = 3）。对新鲜组织切片进行体外肿瘤切片成像。通过血液学、生化和组织病理学分析，在健康小鼠（n = 5）中评估生物安全性。
PSMA-OSP NPs在NIR-II窗口表现出优异的光学性质，包括高光稳定性、可忽略的自发荧光和深部组织穿透性。体外试验证实其对PSMA阳性细胞具有选择性结合，而体内成像显示肿瘤持续蓄积，注射后48小时的峰值肿瘤-背景比值（TBR）为7.40±1.28。这一性能显著超过OTL78和Cy-KUE-OA，可以实现灵活的手术规划和实时术中引导。在体外组织成像中，PSMA-OSP NPs无需全身给药即可提供高对比度的肿瘤轮廓。生物安全性评估显示无明显全身毒性，生物分布分析表明其通过肝脏代谢和胆汁清除。
PSMA-OSP NPs是一种有前景的NIR-II荧光探针，具有优异的肿瘤特异性、深部组织成像能力和良好的生物相容性，支持其在荧光引导手术和体外肿瘤评估中的应用。
