The insulin-like growth factors (IGFs) system regulates cell growth, differentiation and energy metabolism and plays crucial role in the regulation of key aspects of tumor biology, such as cancer cell growth, survival, transformation and invasion. The current focus for cancer therapeutic approaches have shifted from the conventional treatments towards the targeted therapies and the IGF system has gained a great interest as anti-cancer therapy. The proliferative, anti-apoptotic and transformation effects of IGFs are mainly triggered by the ligation of the type I IGF receptor (IGF-IR). Thus, aiming at developing novel and effective cancer therapies, different strategies have been employed to target IGF system in human malignancies, including but not limited to ligand or receptor neutralizing antibodies and IGF-IR signaling inhibitors. In this review, we have focused on the clinical studies that have been conducted targeting the various components of the IGF system for the treatment of different types of cancer, providing a description and the challenges of each targeting strategy and the degree of success.

中文翻译：

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针对IGF系统各个组成部分的人体临床研究表明，在癌症治疗方面缺乏疗效。

胰岛素样生长因子（IGFs）系统调节细胞生长，分化和能量代谢，并在调节肿瘤生物学关键方面（例如癌细胞的生长，存活，转化和侵袭）中发挥关键作用。当前对于癌症治疗方法的关注点已经从常规治疗转向目标疗法，并且IGF系统作为抗癌治疗引起了极大的兴趣。IGFs的增殖，抗凋亡和转化作用主要由I型IGF受体（IGF-1R）的连接触发。因此，为了开发新颖和有效的癌症疗法，已经采用了不同的策略来靶向人类恶性肿瘤中的IGF系统，包括但不限于配体或受体中和抗体和IGF-1R信号抑制剂。在这篇评论中