基于3D类器官模型探索FOXA1去泛素化调控肝癌介入栓塞后血管新生的机制研究

The local hypoxia micro-environment after interventional embolization of hepatocellular carcinoma (HCC) is an important factor of tumor angiogenesis, which seriously affects the long-term efficacy of HCC. Recently, the emergence of organoid-like organs (Organoids) based on three-dimensional (3D) cell culture technology has been regarded as an ideal model for cancer research, because organoids can mimic the real cancer micro-environment. However, there are few reports on three-dimensional organoids of human blood vessels. Previously, we have not only established the 3D induction system of vascular endothelial cells and smooth muscle cells by using human iPS cell lines, but also successfully cultured 3D HCC organoids. Furthermore, according to the TCGA database, we have found that transcription factor FOXA1 may play a role in both hepatocellular carcinoma and angiogenesis, and deubiquitinase USP37 is one of the main regulator of the stability of FOXA1. Thus, this project aims to: 1) to establish and identify 3D culture system for human blood vessel organoids; 2) to study the regulatory mechanisms of angiogenesis through FOXA1 deubiquitination inhuman blood vessel organoids; 3) to verify the potential of deubiquitination inhibitors to interfere with angiogenesis in animal models. This innovative study ustilize 3D blood vessel organoids to elucidate the new mechanisms of angiogenesis under hypoxia stimuli, and optimize present clinical intervention strategies in order to improve the long-term prognosis of patients with hepatocellular carcinoma undergoing interventional embolization.

肝癌介入栓塞术后“局部缺氧”是肿瘤微血管形成的重要因素，严重影响其远期疗效。近年来基于三维（3D）细胞培养技术发展而来的类器官（Organoids）的出现因可接近体内“真实”的微环境而被视为肿瘤研究的理想模型，而针对血管的3D类器官却鲜有报道。申请人前期在肝癌3D类器官的基础上初步完成了血管内皮及平滑肌细胞的3D诱导分化体系，结合TCGA数据库发现转录因子FOXA1可能在肝癌及血管形成过程中均发挥作用，并进一步发现去泛素化酶USP37可能是维持FOXA1稳定性的主要机制。基于此，本项目拟开展：1）人血管类器官的3D培养体系的建立及鉴定；2）基于血管3D类器官研究FOXA1去泛素化介导血管新生的调控机制；3）动物水平验证去泛素化抑制剂干预血管新生的转化潜能。本研究创新性地立足于3D血管类器官，有望解析缺氧下血管新生的全新机制和优化其临床干预策略，从而改善肝癌介入栓塞患者的远期预后。

介入栓塞治疗为核心的综合治疗策略已成为中晚期肝癌首选的治疗手段，血管栓塞之后肿瘤微环境的变化是影响远期疗效和预后的重要因素。为了更加真实模拟肿瘤及周围血管所处的内在病理微环境，模拟原位组织或器官的复杂空间形态和体内特征，全新认识缺氧微环境下血管新生的深层次机理，对优化临床上肝癌介入栓塞术后的抗肿瘤血管治疗策略具有重要的临床意义。基于此，我们成功建立3D培养类器官作为本研究的研究模型，用于后续模拟缺氧等微环境机制研究的基础；此外，本项目还针对泛素化相关的调控机制进行深入研究，发现经过SUMO1介导的肝癌介入栓塞术后肿瘤转移调节信号通路，并通过前沿的三维基因组学测序分析，深度解析了肝癌细胞染色质中特异的三维基因组结构及表观遗传学特征；最后，肿瘤血管新生是导致肿瘤转移复发的重要因素，因此，本项目也着重研究了血管内皮细胞受外泌体非编码RNA调控的表观遗传学机制。通过系列的研究，我们的结果将为肝癌联合介入栓塞的治疗提供更加精准有效的干预策略。