The important role of insulin-like growth factor 1 receptor (IGF-1R) in malignant tumors has been well established. Increased IGF-1R activity promotes cancer cell proliferation, migration, and invasion and is associated with tumor metastasis, treatment resistance, poor prognosis, and shortened survival in patients with cancer. However, while IGF-1R has become a promising target for cancer therapy, IGF-1R-targeted therapy is ineffective in unselected patients. It is therefore essential to evaluate IGF-1R expression before treatment in order to identify responsive patients, monitor therapy efficacy, and estimate prognosis. Insulin-like growth factor 1 receptor molecular imaging is an optimal method for assessing the expression of IGF-1R in vivo accurately and noninvasively. In this review, we will summarize the current status of IGF-1R molecular imaging in cancer, in which 5 major classes of ligands that have been developed for noninvasive IGF-1R molecular imaging will be discussed: natural ligands, monoclonal antibodies, antibody fragments, affibodies, and small molecules. For decades, IGF-1R molecular imaging is studied in full swing and more effort is needed in the future.

中文翻译：

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癌症中IGF-1R的分子成像。

胰岛素样生长因子1受体（IGF-1R）在恶性肿瘤中的重要作用已得到公认。IGF-1R活性增加会促进癌细胞的增殖，迁移和侵袭，并与肿瘤转移，治疗耐药性，预后差和癌症患者的生存期缩短有关。但是，尽管IGF-1R已成为癌症治疗的有希望的靶标，但以IGF-1R为靶标的治疗对未选患者无效。因此，必须在治疗前评估IGF-1R的表达，以识别反应性患者，监测治疗效果并评估预后。胰岛素样生长因子1受体分子成像是一种准确，无创地评估IGF-1R在体内表达的最佳方法。在这篇评论中 我们将总结癌症中IGF-1R分子成像的现状，其中将讨论为非侵入性IGF-1R分子成像开发的五种主要配体类别：天然配体，单克隆抗体，抗体片段，亲和性和小分子分子。几十年来，对IGF-1R分子成像的研究如火如荼，在未来需要付出更多的努力。