Tietz Ole, Kamaly Nazila, Smith Graham, Shamsaei Elham, Bhakoo Kishore K, Long Nicholas J, Aboagye Eric O
Department of Surgery and Cancer, Comprehensive Cancer Imaging Centre, Hammersmith Hospital, Imperial College London London, W12 0NN, UK.
Am J Nucl Med Mol Imaging. 2013 Jul 10;3(4):372-83. Print 2013.
The G-protein coupled C-X-C chemokine receptor type 4 (CXCR4) is highly overexpressed in a range of cancers and is therefore an excellent biomarker for cancer imaging. To this end targeted iron oxide nanoparticles were developed and utilised for in vitro imaging of MDA-MB-231 breast cancer cells overexpressing the CXCR4 receptor. Nanoparticles comprising an iron oxide core, encapsulated in a stabilising epichlorohydrin crossed-linked dextran polymer, were conjugated to a cyclopentapeptide with affinity to the CXCR4 receptor. The particles were characterized for their size, surface charge and r2 relaxivity at 4.7 T. MR imaging of the CXCR4 receptor with targeted iron oxide nanoparticles revealed an approximately 3-fold increase in T2 signal enhancement of MDA-MB-231 cells compared to non-targeted controls. Prussian blue staining of labeled MDA-MB-231 cells revealed darker and more intense staining of the cellular membrane. This study demonstrates the potential of targeted iron oxide nanoparticles for the imaging of the CXCR4 receptor by magnetic resonance imaging (MRI).
G蛋白偶联的C-X-C趋化因子受体4型（CXCR4）在一系列癌症中高度过表达，因此是癌症成像的优秀生物标志物。为此，开发了靶向氧化铁纳米颗粒，并将其用于对过表达CXCR4受体的MDA-MB-231乳腺癌细胞进行体外成像。包含氧化铁核心、包裹在稳定的环氧氯丙烷交联葡聚糖聚合物中的纳米颗粒，与对CXCR4受体具有亲和力的环五肽缀合。对这些颗粒的尺寸、表面电荷和4.7 T时的r2弛豫率进行了表征。用靶向氧化铁纳米颗粒对CXCR4受体进行磁共振成像显示，与非靶向对照相比，MDA-MB-231细胞的T2信号增强约3倍。对标记的MDA-MB-231细胞进行普鲁士蓝染色，显示细胞膜染色更深、更强烈。这项研究证明了靶向氧化铁纳米颗粒通过磁共振成像（MRI）对CXCR4受体进行成像的潜力。
