Key Laboratory of Laparoscopic Technology of Zhejiang Province, Department of General Surgery, Sir Run-Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, 310016, China.
Zhejiang Research and Development Engineering Laboratory of Minimally Invasive Technology and Equipment, Zhejiang Minimal Invasive Diagnosis and Treatment Technology Research Center of Severe Hepatobiliary Disease, Hangzhou, 310016, China.
Hepatol Int. 2024 Feb;18(1):91-107. doi: 10.1007/s12072-023-10552-7. Epub 2023 Jun 22.
Intrahepatic cholangiocarcinoma (ICC) is the second most common primary liver malignancy. Although its incidence is lower than that of hepatocellular carcinoma (HCC), ICC has a worse prognosis, and it is more prone to recur and metastasize, resulting in a far greater level of malignancy.
Bioinformatics analysis and qRT-PCR were applied to assess the level of miR-122-5p and IGFBP4. Western blot, transwell assays, wound-healing assays, real-time cellular invasion monitoring, in vivo study were applied to explore the function of miR-122-5p and IGFBP4. Dual luciferase reporter assays and chromatin isolation by RNA purification (ChiRP) were applied to explore the regulation of IGFBP4 by miR-122-5p.
Using The Cancer Genome Atlas (TCGA) data set, Sir Run Run Shaw hospital data set and bioinformatics analyses, we identified miR-122-5p as a potential tumor suppressor in ICC and validated its suppressive effect in metastasis and invasion of ICC. Transcriptome sequencing, rescue and complement experiments were used to identify insulin-like growth factor binding protein 4 (IGFBP4) as a target of miR-122-5p. The mechanism by which miR-122-5p regulates IGFBP4 was clarified by chromatin separation RNA purification technology, and dual-luciferase reporter assays. We discovered a rare novel mechanism by which miR-122-5p promotes IGFBP4 mRNA transcription by binding to its promoter region. Furthermore, in mouse orthotopic metastasis model, miR-122-5p inhibited the invasion of ICC.
In summary, our study revealed a novel mechanism of miR-122-5p and function of the miR-122-5p/IGFBP4 axis in the metastasis of ICC. We also highlighted the clinical value of miR-122-5p and IGFBP4 in inhibiting ICC invasion and metastasis.
肝内胆管癌（ICC）是第二常见的原发性肝脏恶性肿瘤。虽然其发病率低于肝细胞癌（HCC），但 ICC 的预后更差，更容易复发和转移，恶性程度更高。
应用生物信息学分析和 qRT-PCR 评估 miR-122-5p 和 IGFBP4 的水平。应用 Western blot、transwell 测定、划痕愈合测定、实时细胞侵袭监测、体内研究来探讨 miR-122-5p 和 IGFBP4 的功能。应用双荧光素酶报告基因检测和 RNA 免疫共沉淀（ChiRP）实验来探索 IGFBP4 受 miR-122-5p 的调控。
利用 The Cancer Genome Atlas（TCGA）数据集、浙江大学医学院附属邵逸夫医院（Sir Run Run Shaw Hospital）数据集和生物信息学分析，我们鉴定出 miR-122-5p 是 ICC 中的一种潜在肿瘤抑制因子，并验证了其在 ICC 转移和侵袭中的抑制作用。转录组测序、挽救和补充实验用于鉴定胰岛素样生长因子结合蛋白 4（IGFBP4）是 miR-122-5p 的靶标。通过染色质分离 RNA 纯化技术和双荧光素酶报告基因检测实验阐明了 miR-122-5p 调节 IGFBP4 的机制。我们发现了 miR-122-5p 通过结合其启动子区域促进 IGFBP4 mRNA 转录的罕见新机制。此外，在小鼠原位转移模型中，miR-122-5p 抑制了 ICC 的侵袭。
综上所述，我们的研究揭示了 miR-122-5p 的新机制以及 miR-122-5p/IGFBP4 轴在 ICC 转移中的作用。我们还强调了 miR-122-5p 和 IGFBP4 在抑制 ICC 侵袭和转移中的临床价值。
