Department of Neuroradiology, University of Tübingen, Hoppe-Seyler-Str.3, 72076 Tübingen, Germany.
Chem Biol Drug Des. 2010 Apr;75(4):369-74. doi: 10.1111/j.1747-0285.2009.00936.x. Epub 2010 Jan 19.
The interleukin 6 receptor (IL-6R) and its ligand interleukin 6 (IL-6) play a crucial role in glioma growth and development accomplished by autocrine growth promotion and induction of angiogenesis via activation of vascular epithelial growth factor A (VEGF-A). Therefore, IL-6R represents a target for both therapy (preventing VEGF-A activation by blocking the receptor) and imaging (higher receptor density on tumor cells). A short heptapeptide that selectively binds to IL-6R and which inhibits the effect of IL-6 was coupled to the magnetic resonance imaging (MRI) contrast agent gadolinium (Gd)-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) and the fluorescent dye rhodamine. MRI, confocal laser scanning microscopy, and flow cytometry showed that our IL-6-DOTA-rhodamine conjugate was taken up into the cytoplasm of human U373 glioma cells without any cytotoxic effects. Competition experiments indicate that this uptake was receptor-mediated. This conjugate might be used for future MRI studies of brain tumors after systemic or intraoperative local application. The cytoplasm specificity of the conjugate also makes it a potential building block for the design of future cytoplasm-directed imaging and therapeutic conjugates.
白细胞介素 6 受体 (IL-6R) 和其配体白细胞介素 6 (IL-6) 通过激活血管内皮生长因子 A (VEGF-A) 实现自分泌生长促进和诱导血管生成,在神经胶质瘤的生长和发展中发挥着关键作用。因此,IL-6R 既是治疗的靶点(通过阻断受体来阻止 VEGF-A 的激活),也是成像的靶点(肿瘤细胞上的受体密度更高)。一种短的七肽选择性地与 IL-6R 结合,并抑制 IL-6 的作用,该七肽与磁共振成像 (MRI) 造影剂钆 (Gd)-1,4,7,10-四氮杂环十二烷-1,4,7,10-四乙酸 (DOTA) 和荧光染料罗丹明偶联。MRI、共聚焦激光扫描显微镜和流式细胞术显示,我们的 IL-6-DOTA-罗丹明缀合物被摄取到人类 U373 神经胶质瘤细胞的细胞质中,没有任何细胞毒性作用。竞争实验表明,这种摄取是受体介导的。该缀合物可用于系统或术中局部应用后对脑肿瘤进行未来的 MRI 研究。该缀合物的细胞质特异性也使其成为未来针对细胞质的成像和治疗性缀合物设计的潜在构建块。