中药单体蟾毒灵调控Angiopoietin-2蛋白分泌抑制肝癌血管生成的分子机制研究

Although effective drugs targeting hepatic carcinoma are limited, drugs of anti-angiogenesis are considered effective in anti-cancer therapy. It has been reported that Angiopoietin-2 plays a crucial role in the growth and metastasis of hepatic carcinoma by modulating vascular formation. However, drugs that targeting Angiopoietin-2 are not developed and applied in clinical practice. Bufalin, extracted from the skin and parotid venom glands of toads, has been demonstarted to suppress tumor vascular formation in our previous study. And we have found that Angiopoietin-2 expression was downregulated in bufalin-treated hepatoma cells. Therefore, we put forward the hypothesis: bufalin can inhibit the angiogenesis of hepatocellular carcinoma and the mechanism might be related to regulate protein secretion of angiopoietin-2. Thus, the study first aims to explore the molecular mechanisms of bufalin’s anti-angiogenic effect and bufalin-induced Angiopoietin-2 decrease in vitro through the co-culture of hepatocellular carcinoma cells and endothelial cells. Moreover, models of abdominal intradermal tumor angiogenes in nude mice are also established to further validate such effect of bufalin. On the whole, this study investigates the anti-angiogenic role of bufalin from the aspects of animals, tissues, cells and molecules. In conclusion, the study would provide more theoretical foundation to the application of Chinese medicine in anti-cancer therapy. It can also broaden the field of anti-cancer drugs derived from Chinese medicine and contributes to the development of the translational medicine.

肝癌缺乏有效治疗药物，抗血管生成是一种有效的治疗途径。近期研究表明，Angiopoietin-2蛋白在肝癌血管生成以及肝癌生长、转移中扮演着重要角色。然而，目前尚无有效靶向该蛋白的药物。我们前期研究发现，中药蟾皮有效活性单体蟾毒灵具有一定抑制肝癌血管生成的能力，并可抑制肝癌Angiopoietin-2蛋白的分泌。因此，我们提出假说：蟾毒灵可抑制肝癌血管生成，其机制可能与调控Angiopoietin-2蛋白的分泌有关。本课题将在体外构建肝癌细胞、血管内皮细胞共培养模型，研究蟾皮有效活性单体蟾毒灵调控Angiopoietin-2蛋白的分泌，抑制肝癌血管生成的分子机制，并构建裸小鼠腹部皮内肿瘤血管形成模型，进行体内分子生物学验证，从动物、组织、细胞、分子层面深入阐明其具体调控的可能分子机制。研究结果将为中医药抗肿瘤研究提供一定实验依据，对于拓宽中医药抗肿瘤研究领域以及后期临床转归具有重要的意义。

肝癌缺乏有效治疗药物，抗血管生成是一种有效的治疗途径。Angiopoietin-2蛋白在肝癌血管生成以及肝癌生长、转移中扮演着重要角色。然而，目前尚无有效靶向该.蛋白的药物。课题组在前期研究基础上，通过构建动物皮下抑制瘤模型、动物皮内肿瘤血管生成模型以及体外小管形成实验、动脉出芽实验等发现，中药单体蟾毒灵具有抑制肝癌血管生成的能力；后续通过体内外实验证明Angiopoietin-2蛋白在其中扮演了重要的角色；最后利用分子生物学的方法，从动物、组织、细胞、分子层面深入阐明了中药单体蟾毒灵调控Angiopoietin-2蛋白的分泌抑制肝癌血管生成的分子机制，并发现可能与AKT/mTOR相关信号通路有关。另外研究发现中药单体蟾毒灵联合索拉菲尼抗血管生成作用更为明显，研究结果将为中西医结合抗肿瘤研究提供一定实验依据，对于拓宽中医药抗肿瘤研究领域以及后期临床转归具有重要的意义。