靶向MRI纳米探针在胰腺神经内分泌肿瘤诊断中的应用

The application of the target MRI nano probe in the diagnosis of pancreatic neuroendocrine tumor

目的:探讨靶向磁共振成像(MRI)纳米探针在胰腺神经内分泌肿瘤(pNENs)诊断中的应用价值。方法:选取60只雄性昆明裸鼠,按随机数字表法分为A组、B组、C组,每组20只,建立pNENs细胞株QGP-1原位移植瘤裸鼠模型。A组注射负载超顺磁性四氧化三铁纳米粒子(SPIO)的纳米胶束,B组注射5 mg Fe/kg负载SPIO和Octreotide的纳米胶束,C组注射10 mg Fe/kg负载SPIO和Octreotide的纳米胶束,分别于注射前及注射后0.5 h、1 h、2 h、6 h、12 h进行MRI扫描,分析靶向MRI纳米探针对pNENs的诊断价值。结果:在MTT比色试验中,3组细胞活性比较差异无统计学意义(P>0.05)。3组注射后0.5 h、1 h、2 h、6 h、12 h的横向弛豫时间(T2)均较注射前明显下降,A组各时间段T2下降比例明显低于B组,B组各时间段T2下降比例明显低于C组,差异均有统计学意义(均P<0.05);在普鲁士蓝染色试验中,A组、B组、C组细胞内均可见蓝色颗粒,A组蓝色颗粒数明显少于B组,B组明显少于C组,差异有统计学意义(均P<0.05)。结论:负载SPIO和Octreotide的纳米探针对pNENs细胞株QGP-1原位癌细胞具有良好的靶向性,对pNENs早期诊断具有较大的应用潜力。

Objective:To investigate the value of the target magnetic resonance(MRI)nano probe in the diagnosis of pancreatic neuroendocrine tumor(pNENs).Methods:60 male Kunming nude mice were randomized to 3 groups(20 cases per group):group A,group B and group C.A nude mouse model of P-NENs cell line QGP-1 in situ xenografts was established.Group A mice were injected with nano micelles loaded with superparamagnetic iron oxide nanoparticles(SPIO),group B mice were injected with 5 mg Fe/kg loaded nanomicelles of SPIO and Octreotide,and mice in group C were injected with 10 mg Fe/kg loaded nanomicelles of SPIO and Octreotide.Before injection and after 0.5 h,1 h,2 h,6 h and 12 h of injection,the MRI scanning was conducted.Results:In the MTT test,no significant difference was found in the cell activity among the three groups(P>0.05).After 0.5 h,1 h,2 h,6 h and 12 h of injection,the lateral relaxation time(T2)was significantly decreased in all groups,and the decrease was the most significant in group C(P<0.05).In Prussian blue staining test,the number of blue particles was the highest in group C(P<0.05).Conclusion:The nanoscale probes loaded with SPIO and Octreotide had good targeting ability on the pNENs cell line QGP-1 in situ cancer cells.It might possess great potential for the early diagnosis of pNENs.