跨膜蛋白BTN3A3在肝癌干性形成与维持中的功能研究

High recurrence and metastasis rate is the bottleneck of hepatocellular carcinoma (HCC) therapy. The maintenance of stemness is the basis of HCC recurrence and metastasis. Therefore, in-depth exploration of new functional proteins to promote the stem of hepatocellular carcinoma cells and development of specific inhibitors will play a crucial role in targeted therapy of HCC. Our previous studies found that transmembrane protein BTN3A3 was expressed in human hepatocellular carcinoma cells and clinical hepatocellular carcinoma samples, and was positively correlated with the stem markers of HCC. Knocking down of BTN3A3 could decrease the expression of stemness marker in cancer cells. Therefore, our project hypothesized that BTN3A3 plays an important role in the maintenance, proliferation, migration and apoptosis of HCC cells. Clinical HCC tissue specimens and cell lines were utilized to study the relationship between BTN3A3 expression and HCC progression. Balling assay, wound-healing, growth curve, and transwell assay were performed to determine the effects of BTN3A3 on biological characteristics of HCC cells. HCC cell transplantation on nude mice and PDX model were established to study the in vivo function of BTN3A3. BTN3A3 antagonist was prepared to explore its effect on experimental treatment of HCC. The study aims to reveal the function of BTN3A3 in regulating HCC occurrence and development, and to elucidate the novel mechanisms of the stem maintenance in HCC cells, which will provide new clues for specific therapies based on targeting HCC stemness.

高复发与转移是肝癌治疗中的瓶颈问题。肝癌干性的维持是肝癌复发转移的基础。深入发掘新的促进肝癌细胞干性的功能蛋白并开发其抑制剂将在肝癌的靶向治疗中起关键作用。我们前期发现跨膜蛋白BTN3A3表达于人肝癌细胞及临床样本中，并与肝癌干性标志物呈正相关。敲低BTN3A3降低肿瘤细胞干性特征分子表达。本项目据此提出：BTN3A3在肝癌细胞干性维持、增殖、迁移、凋亡等方面具有重要作用。拟用肝癌临床组织标本及细胞系研究BTN3A3的表达及与肝癌进程的关系；利用成球、划痕、生长曲线、Transwell等实验确定BTN3A3对肝癌细胞生物学特征的影响；构建人肝癌-裸鼠移植及PDX模型研究BTN3A3的体内功能；制备BTN3A3拮抗剂，探索其在肝癌实验性治疗的效果。以期揭示BTN3A3在调控肝癌细胞干性以及肝癌发生发展中的功能及其新机制，并希望为针对肝癌干性的特异性疗法提供新思路。

高复发与转移是肝癌治疗中的瓶颈问题，因此深入发掘新的促进肝癌细胞恶性进程及干性维持的功能蛋白并开发其抑制剂将在肝癌的靶向治疗中起关键作用。据此，我们的研究工作率先验证了BTN3A3在肝癌组织及恶性程度高的肝癌细胞系中高表达。其次，通过构建稳定过表达、敲低、回转等细胞及动物实验，证实了BTN3A3可促进肝癌的增殖、迁移、侵袭、干性维持并抑制凋亡。在此基础上，团队还进一步从糖酵解代谢与不对称分裂调控等角度阐释了BTN3A3在调控肝癌恶性进程及干性维持中的新的分子机制，这有助于系统性描述肿瘤细胞表达BTN3A3蛋白的功能。此外，研究团队还率先筛选了BTN3A3的功能性拮抗剂，包括单克隆抗体与小分子抑制剂的设计、合成与验证工作，探索其在肝癌中的实验性治疗功能，综上，BTN3A3很有可能成为新的肝癌治疗的膜分子靶标，为临床肝癌的治疗提供新的药物靶标和治疗方案。