前列腺癌EpCAM特异性分子探针的构建及其在体MR成像研究  

Construction of prostate cancer EpCAM-specific molecular probe and MR imaging in vivo

作　　者：仲津漫 丁健科 刘朵朵 陈欣[1] 杨全新[1] ZHONG Jin-man;DING Jian-ke;LIU Duo-duo(Department of Radiology,Second Affiliated Hospital of Xi'an Jiaotong University,Xi'an 710004,China)

机构地区：[1]西安交通大学第二附属医院医学影像科,西安710004 [2]空军军医大学第一附属医院整形外科,西安710032

出　　处：《放射学实践》2023年第2期188-193,共6页Radiologic Practice

基　　金：陕西省重点研发计划一般项目(2021SF-267)。

摘　　要：目的:利用金磁纳米微粒偶联核酸适配体构建前列腺癌EpCAM特异性分子探针Ep1-GoldMag,探讨其对EpCAM阳性前列腺癌的亲和性及其在体MR成像能力。方法:将金磁纳米微粒偶联前列腺癌EpCAM核酸适配体制备分子探针Ep1-GoldMag。采用免疫荧光实验检测Ep1-GoldMag靶向EpCAM阳性前列腺癌组织细胞的能力;构建前列腺癌EpCAM荷瘤裸鼠模型,采用免疫组化检测裸鼠肿瘤及其重要脏器组织的EpCAM表达情况。将Ep1-GoldMag注入裸鼠体内,在注射后不同时间点行MRI扫描,比较注射前后各时间点的肿瘤T_(2)WI信号强度,探讨分子探针在体MR成像的可行性。结果:成功制备Ep1-GoldMag,并证实其能特异性识别EpCAM阳性前列腺癌组织细胞。对裸鼠注射Ep1-GoldMag前后行MRI扫描,结果显示注入1 h后,肿瘤T_(2)WI信号明显减低,6 h后T_(2)WI信号持续减低,12 h后T_(2)WI信号略升高,但与注射前相比仍呈低信号,而对照组注射前后T_(2)WI信号强度未见减低,实验组与对照组组间以及实验组内部注射前后各时间点的信号差异均有统计学意义(P<0.05)。结论:本研究制备的分子探针Ep1-GoldMag具有良好的EpCAM前列腺癌组织细胞特异性,并能在MR上特异性成像。Objective:To construct the molecular probe of Ep1-GoldMag with EpCAM-specific aptamer mediated with GoldMag nanoparticles,and investigate its binding affinity for EpCAM-positive prostate cancer and identify its ability of MR imaging in vivo.Methods:GoldMag nanoparticles were used to conjugate with EpCAM-specific aptamers to construct Ep1-GoldMag.Immunofluorescence assay was used to evaluate the binding affinity of Ep1-GoldMag for EpCAM-positive prostate cancer cells and tissues.Prostatic tumor-bearing nude mice models were established.Immunohistochemical staining was used to identify the expression of EpCAM in tumor tissues and major organs.MRI scans were performed at different timepoints after Ep1-GoldMag injection.The signal intensity of tumors on T_(2)WI before and after injection at different time points was compared to explore the feasibility of molecular probe in MR imaging in vivo.Results:Ep1-GoldMag was successfully constructed and proved to specifically recognize EpCAM-positive prostate cancer cells and tissues.MRI scans showed that the signal intensity of tumors on T_(2)WI decreased significantly 1h after injection,persistent to 6h after injection,and slightly increased 12h after injection,but still showed low signal intensity compared with that before the injection.While the signal intensity of T_(2)WI in control group showed no decrease after injection.There were significant differences of signal intensity between the experimental group and the control group as well as each time point within the experimental group(All P<0.05).Conclusion:The molecular probe of Ep1-GoldMag can specifically bind to EpCAM-positive prostate cancer cells and tissues and can be used for specific MR imaging.

关 键 词：前列腺癌 核酸适配体 磁共振成像 金磁纳米微粒 分子探针 

分 类 号：R737.25[医药卫生—肿瘤] R445.2[医药卫生—临床医学] R73-3