胃癌新生血管靶向性双模态分子探针的制备与表征  

Preparation and characterization of dual-modality molecular probes for imaging angiogenesis of gastric cancer

作　　者：康晓伟[1] 乔瑞瑞[2] 梁树辉[3] 吴开春[3] 刘先平[1] 印弘[1] 高明远[2] 魏光全[1] 

机构地区：[1]第四军医大学西京医院放射科,西安710032 [2]中国科学院化学研究所 [3]第四军医大学西京消化病医院肿瘤生物学国家重点实验室

出　　处：《中华放射学杂志》2014年第5期369-374,共6页Chinese Journal of Radiology

基　　金：国家自然科学基金资助项目（81071209,81090270）

摘　　要：目的：构建靶向胃癌新生血管的特异性MR光学双模态分子探针，并初步研究其物理特征、体外细胞毒性及不同脉冲序列的磁化效应。方法将荧光标记的胃癌新生血管靶向性环肽GX1-Cy5.5与表面功能化的磁性纳米颗粒按照不同摩尔质量（1∶100、1∶500）共价耦合，获得双模态探针DPs100（简称DPs）和DPs500，测定其水合粒径和Zeta电位，并估算偶联结合率。采用二苯基四氮唑溴盐比色（ MTT）法测定DPs对人脐静脉内皮细胞HUVECs和胃癌细胞BGC823活性率的影响。配置不同浓度DPs溶液行MR扫描，观察在不同扫描序列下的相对信号强度（ΔSI ）。不同浓度（0.00、1.25、2.50、15.00、50.00、100.00和150.00μg/ml） DPs处理HUVECs和BGC-823后测得的A值采用单因素方差分析比较；FSE、快速扰相梯度回波（ FSPGR ）和单次激发快速自旋回波（ SSFSE ）序列间ΔSI的比较采用配对资料Wilcoxon符号秩和检验。结果靶向胃癌新生血管双模态探针构建成功。氧化铁颗粒、DPs100和 DPs500的平均水合粒径分别为（35.23±0.07）、（39.49±0.16）和（40.43±1.70）nm；平均Zeta电位分别为（0.31±0.20）、（-4.15±0.79）和（-10.51±2.37） mV。 DPs100和DPs500探针的多肽偶联率分别为92％和94％。不同浓度DPs对HUVECs细胞的A值分别为0.76±0.04、0.80±0.03、0.79±0.05、0.75±0.06、0.74±0.05、0.77±0.01和0.71±0.04，对BGC823细胞的A值分别为0.38±0.04、0.43±0.04、0.41±0.03、0.43±0.07、0.44±0.04、0.41±0.07和0.40±0.04，差异均无统计学意义（F值分别为0.94、0.51，P值均＞0.05）。 T1WI信号强度随DPs浓度的增加先升高后降低，FSPGR T1WI相对信号强度大于FSE T1WI（Z＝-3.294，P＜0.05）；T2WI信号强度随DPs浓度的增大逐渐增加，当DPs＞10μg/ml时，FSE T2 WI与SSFSE T2倡WI相对信号强度差异无统计学意义（Z＝-7.110，P＞0.05）；当DPs≤10μg/ml时，SSFSE T2倡WI较FSE T2WI信号降低�Objective To develop an MR optical dual-modality probe targeting angiogenesis of gastric cancer and to study its physical characteristics , in vitro cytotoxicity and magnetic effects of different pulse sequences on 3 T clinical MR scanner.Methods We conjugated GX1-Cy5.5, a novel gastric cancer neo-vasculature targeted peptide labeled with Cy 5.5, to the surface functionalized magnetic nanoparticles according to different molecular weights （1∶100, 1∶500）,resulting in dual-modality probe DPs100 and DPs500 （named DPs）.The hydrodynamic size and zeta potential of DPs and DPs 500 were analyzed by nano-ZS.The human umbilical vein endothelial cells （HUVECs） and BGC-823 cells were treated with DPs for 24 h, and methyl thiazol tetrazolium （ MTT） method was used to detect the survival rate of cells.DPs with different＆amp;nbsp;concentrations were scanned on different MR sequences , and then the relative signal intensity was observed.The absorbance of HUVECs and BGC823 cells treated with DPs of different concentration （0.00, 1.25, 2.50, 15.00, 50.00, 100.00 and 150.00 μg/ml） were compared with single factor analysis of variance.Relative signal intensity of different MR sequences was compared using a paired Wilcoxon signed-rank test.Results The dual-modality probe targeting angiogenesis of gastric cancer was successfully constructed.The hydrodynamic size of iron oxide nanoparticles , DPs100 and DPs500 was （35.23 ±0.07）, （39.49 ±0.16） and （40.43 ±1.70） nm and the Zeta potential was （0.31 ±0.20）, （ -4.15 ±0.79） and （ -10.51 ± 2.37） mV.The coupled rates of DPs 100 and DPs500 with polypeptide were 92%and 94% respectively.The absorbance of HUVECs and BGC823 cells treated with DPs of different concentrations were 0.76 ±0.04, 0.80 ±0.03, 0.79 ±0.05, 0.75 ±0.06, 0.74 ±0.05, 0.77 ±0.01,0.71 ±0.04 and 0.38 ±0.04, 0.43 ±0.04, 0.41 ±0.03, 0.43 ±0.07, 0.44 ±0.04, 0.41 ±0.07 and 0.40 ±0.04, there was no statistical significance （ F=0.94, 0.51;P〈0.05）.The signal int

关 键 词：胃肿瘤 分子探针 磁共振成像 

分 类 号：R735.2[医药卫生—肿瘤] R445.2[医药卫生—临床医学]