Ding Xiao-Jing, Cai Xue-Mei, Wang Qian-Qian, Liu Ning, Zhong Wei-Long, Xi Xiao-Nan, Lu Ya-Xin
College of Pharmacy, Nankai University, Tianjin 300350, PR China.
Huabei Petroleum Administration Bureau General Hospital, Renqiu 062550, PR China.
Phytomedicine. 2024 Sep;132:155833. doi: 10.1016/j.phymed.2024.155833. Epub 2024 Jun 26.
Colorectal cancer (CRC) is the second most common cause of cancer-related mortality and is characterised by extensive invasive and metastatic potential. Previous studies have shown that vitexicarpin extracted from the fruits of Vitex rotundifolia can impede tumour progression. However, the molecular mechanisms involved in CRC treatment are still not fully established.
Our study aimed to investigate the anticancer activity, targets, and molecular mechanisms of vitexicarpin in CRC hoping to provide novel therapies for patients with CRC.
STUDY DESIGN/METHODS: The impact of vitexicarpin on CRC was assessed through various experiments including MTT, clone formation, EDU, cell cycle, and apoptosis assays, as well as a tumour xenograft model. CETSA, label-free quantitative proteomics, and Biacore were used to identify the vitexicarpin targets. WB, Co-IP, Ubiquitination assay, IF, molecular docking, MST, and cell transfection were used to investigate the mechanism of action of vitexicarpin in CRC cells. Furthermore, we analysed the expression patterns and correlation of target proteins in TCGA and GEPIA datasets and clinical samples. Finally, wound healing, Transwell, tail vein injection model, and tissue section staining were used to demonstrate the antimetastatic effect of vitexicarpin on CRC in vitro and in vivo.
Our findings demonstrated that vitexicarpin exhibits anticancer activity by directly binding to inosine monophosphate dehydrogenase 2 (IMPDH2) and that it promotes c-Myc ubiquitination by disrupting the interaction between IMPDH2 and c-Myc, leading to epithelial-mesenchymal transition (EMT) inhibition. Vitexicarpin hinders the migration and invasion of CRC cells by reversing EMT both in vitro and in vivo. Additionally, these results were validated by the overexpression and knockdown of IMPDH2 in CRC cells.
These results demonstrated that vitexicarpin regulates the interaction between IMPDH2 and c-Myc to inhibit CRC proliferation and metastasis both in vitro and in vivo. These discoveries introduce potential molecular targets for CRC treatment and shed light on new mechanisms for c-Myc regulation in tumours.
结直肠癌（CRC）是癌症相关死亡的第二大常见原因，具有广泛的侵袭和转移潜能。先前的研究表明，从蔓荆子果实中提取的紫铆因可阻碍肿瘤进展。然而，CRC治疗所涉及的分子机制仍未完全明确。
我们的研究旨在探讨紫铆因在CRC中的抗癌活性、靶点及分子机制，希望为CRC患者提供新的治疗方法。
研究设计/方法：通过MTT、克隆形成、EDU、细胞周期和凋亡检测以及肿瘤异种移植模型等各种实验评估紫铆因对CRC的影响。采用CETSA、无标记定量蛋白质组学和Biacore来鉴定紫铆因靶点。运用蛋白质免疫印迹法（WB）、免疫共沉淀法（Co-IP）、泛素化检测、免疫荧光法（IF）、分子对接、 MST和细胞转染来研究紫铆因在CRC细胞中的作用机制。此外，我们分析了癌症基因组图谱（TCGA）和基因表达谱交互分析（GEPIA）数据集以及临床样本中靶蛋白的表达模式和相关性。最后，采用伤口愈合实验、Transwell实验、尾静脉注射模型和组织切片染色来证明紫铆因在体外和体内对CRC的抗转移作用。
我们的研究结果表明，紫铆因通过直接结合肌苷单磷酸脱氢酶2（IMPDH2）发挥抗癌活性，并且通过破坏IMPDH2与c-Myc之间的相互作用促进c-Myc泛素化，从而导致上皮-间质转化（EMT）受到抑制。紫铆因在体外和体内均通过逆转EMT来阻碍CRC细胞的迁移和侵袭。此外，通过在CRC细胞中过表达和敲低IMPDH2验证了这些结果。
这些结果表明，紫铆因调节IMPDH2与c-Myc之间的相互作用，从而在体外和体内抑制CRC的增殖和转移。这些发现为CRC治疗引入了潜在的分子靶点，并揭示了肿瘤中c-Myc调控的新机制。
