In the past decade, there have been extensive efforts to open up the Eph/ephrin subfamily of the receptor tyrosine kinase family for diagnostic and therapeutic applications. Besides classical pharmaceutical developments, which focus either on drugs targeting the extracellular ligand binding domains or on the intracellular tyrosine kinase domains of these receptors, there also have been first radiopharmaceutical approaches. Here the focus is on the development of specific and selective probes for molecular imaging, particularly by means of positron emission tomography, and the functional characterization of the Eph/ephrin subfamily in certain target tissues. The aim of this mini-review is to summarize the different approaches toward Eph-targeting radiotracers by using antibodies, peptides, and small molecules and to discuss their radiopharmacological characterization. With regard to the small molecules, further considerations will focus on the design and synthesis of nonradioactive reference compounds and precursors as well as on radiolabeling strategies.

中文翻译：

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放射药物学家和放射化学家关于靶向Eph / Ephrin受体酪氨酸激酶系统的观点。

在过去的十年中，已经进行了广泛的努力来开放受体酪氨酸激酶家族的Eph / ephrin亚家族，用于诊断和治疗应用。除了经典的药物开发（其重点是针对靶向这些受体的细胞外配体结合结构域或细胞内酪氨酸激酶结构域的药物）外，还存在第一种放射性药物方法。在这里，重点是针对分子成像的特异性和选择性探针的开发，特别是借助正电子发射断层扫描，以及某些靶组织中Eph / ephrin亚家族的功能表征。这篇小型综述的目的是总结使用抗体，肽，和小分子，并讨论其放射药理学表征。关于小分子，进一步的考虑将集中在非放射性参考化合物和前体的设计和合成以及放射性标记策略上。