Development of a Metastatic Breast Cancer model in the nude rat for MRI Cell Tra

MRI Cell Tra 裸鼠转移性乳腺癌模型的建立

• 批准号: 7733684
• 负责人: Joseph Frank
• 金额: $ 31.76万
• 依托单位: CLINICAL CENTER
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/7733684
• 关键词: Animals; Bioluminescence; Brain; Brain Neoplasms; Breast Cancer Cell; Breast Cancer Model; Cell Line; Cells; Clinical; Complementary DNA; Complex; Cytokeratin; Detection; Development; Disseminated Malignant Neoplasm; Dose; Firefly Luciferases; Goals; Human; Image; Imaging Techniques; Infiltration; Infusion procedures; Injection of therapeutic agent; Iron; Label; Lesion; Luciferases; Lung; Magnetic Resonance Imaging; Malignant Neoplasms; Maps; Metastatic Lesion; Metastatic Neoplasm to the Bone; Modeling; Monitor; Multimodal Imaging; Natural History; Neoplasm Metastasis; Nude Rats; Numbers; Optics; Pathology; Photons; Physiologic pulse; Protamine Sulfate; Prussian blue; Pulse taking; Purpose; Rattus; Relaxation; Rodent; Rodent Model; Signal Transduction; Spinal Cord; Spleen; Staining method; Stains; Stem cells; Time; Tissues; Week; Weight; bone; clinically relevant; day; disease natural history; ferumoxides; gene therapy; improved; in vivo; lymph nodes; malignant breast neoplasm; neoplastic cell; novel; response; time use; tumor

The purpose of this study was to develop a metastatic brain tumor model of breast cancer in the rat to monitor the natural history of the disease using a multimodal imaging approach with magnetic resonance imaging (MRI) scanner and in vivo bioluminescence imaging (BLI). MDAMB231BR cell line is a brain seeking metastatic breast cancer line that was stably transfected to express the firefly luciferase cDNA (LUC) and was magnetically labeled with ferumoxides protamine sulfate (FEPro) complex ex vivo for early monitoring by MRI. Nude rats underwent intracardiac infusion FEPro ferumoxides labeled MDAMB231BRLUC (231BRL) cells. FEPro labeled 231BRL cells injected rats developed multiple brain and spinal cord metastasis and all rats with brain lesion had multiple skeletal metastasis. Tumor cell infiltrations were also detected to the lung, lymph nodes, and spleen by cytokeratin immunohistochemical staining. Prussian blue positive breast cancer cells could be detected in animals up to 1 week following intracardiac injection of FEPro labeled cells. BLI demonstrated increase in luciferase photon flux activity in the brain and bones of the rats while MRI revealed numerous hypointense regions corresponding to FEPro labeled cells in the brain within the first 3 days following injection of cell. By week 1 the luciferase photon flux activity similar to background photon flux and MRI rarely detected FEPro labeled cells past week 1. By 2 weeks, all animals had brain and skeletal metastasis on BLI and the luciferase activity increased in intensity with time. MRI detected metastatic lesions in the brain as early as week 2 postinfusion of 231BRL cells. The development of this metastatic breast cancer model in the rat allows for the use of imaging techniques to monitor the temporal and spatial migration of tumor cells and evaluate novel treatment strategies. Quantifying the number of labeled stem cells in target tissues is of great importance to optimize dose and timing of cellular therapy. T2 weighted spin echo imaging has been used to quantify the amount of iron within tissue. We has employed a multi-gradient echo pulse sequence to calculate T2* relaxation times to improve the detection of labeled cells within the voxel. To determine if FE-Pro labeled cells could be detected in tissues without the hypointense regions, the metastatic breast cancer model described above was used and fitted the signal intensities from multiecho T2* sequence as a monoexponential decay to calculate T2* maps. After normalizing the T2* values for the total number of voxels and quartile analysis was perform on the histogram distribution of T2* values over the brain, it was possible to compare serial MRI studies over time. There was significant differences in quartile 1 in the number of brain voxels that contained labeled versus baseline on days 1-3 following injection. A significant difference also existed at weeks 1-3 weeks in quartiles 2 and 3 after injection of FE-Pro labeled cells compared to animals that received unlabeled tumor cells. These results suggest that it may be possible to determine the presence of FEPro labeled cells in tissues for longer periods of time using quantitative T2* imaging versus qualitative T2* weighted images.

这项研究的目的是开发大鼠乳腺癌的转移性脑肿瘤模型，以使用磁共振成像（MRI）扫描仪和体内生物发光成像（BLI）的多模式成像方法来监测疾病的自然史。 MDAMB231BR细胞系是一种脑寻求转移性乳腺癌系，稳定转染以表达萤火虫荧光素酶cDNA（LUC），并用铁氧化甲氧化物硫酸硫酸硫酸盐（FEPRO）复合物将MRI的早期监测磁性标记。裸鼠接受了心脏内输注的Fepro人氧化物标记为MDAMB231BRLUC（231BRL）细胞。 FEPRO标记为231BRL细胞注入的大鼠发育于多个脑和脊髓转移，所有患有脑病变的大鼠均具有多个骨骼转移。还通过细胞角蛋白免疫组织化学染色检测到肿瘤细胞浸润到肺，淋巴结和脾脏。在心脏内注射FEPRO标记的细胞后，可以在1周内在动物中检测到普鲁士蓝色阳性乳腺癌细胞。 BLI表明在大脑和大鼠的骨骼中荧光素酶光子通量活性增加，而MRI揭示了在注射细胞后的前3天内与FEPRO标记的大脑标记的细胞相对应的许多低端区域。到第1周，荧光素酶光子通量活性类似于背景光子通量，MRI很少检测到FEPRO标记的细胞过去第1周。到2周时，所有动物在BLI上具有脑和骨骼转移，而荧光素酶活性随着时间的推移而增长。 MRI在231BRL细胞后第2周就检测到大脑中的转移性病变。大鼠转移性乳腺癌模型的发展允许使用成像技术来监测肿瘤细胞的时间和空间迁移并评估新颖的治疗策略。量化靶组织中标记的干细胞的数量对于优化细胞治疗的剂量和时间至关重要。 T2加权自旋回波成像已用于量化组织内的铁量。 我们已经采用了多速率回声脉冲序列来计算T2*松弛时间，以改善体素内标记的细胞的检测。 为了确定在没有低位区域的组织中是否可以在组织中检测到Fe-Pro标记的细胞，使用了上述转移性乳腺癌模型，并拟合了来自多回声T2*序列的信号强度，作为单指数衰减以计算T2*地图。 在对大脑中T2*值的直方图分布进行归一化的T2*值后，可以随着时间的推移比较序列MRI研究。注射后第1-3天，四分位数的脑体素数量与基线相对于基线的脑体素数量有显着差异。与接受未标记的肿瘤细胞的动物相比，在注射Fe-Pro标记的细胞后，在四分位数2和3的第1-3周也存在显着差异。 这些结果表明，有可能使用定量T2*成像与定性T2*加权图像来确定组织中FEPRO标记的细胞在组织中的存在。