抑制外泌体miR-25-LATS2/KLF4信号的核酸纳米复合物的构建及其在肝移植后肝癌复发转移中的作用研究

肝移植后肝癌复发转移是影响移植受者长期生存的重要原因，发现复发转移相关分子标记物并早期干预，有助于降低肝癌复发风险。申请人前期发现外周血外泌体高表达miR-25的肝癌患者在移植后复发比例显著升高，且miR-25可抑制下游靶点LATS2并增强肝癌细胞增殖与迁移能力，并可下调血管内皮细胞KLF4蛋白而参与肿瘤复发转移，但具体机制仍待进一步明确。申请人在前期靶点发现基础上，制备了ROS响应性的B-PDEA/miR-25抑制剂纳米复合物，并包裹原位/转移灶肝癌靶向的SP94多肽或VEGFR2抗体修饰的脂质膜，从而构建肝癌复发转移灶靶向的核酸纳米药物。本项目拟在肝癌细胞、血管内皮细胞、小鼠原位肝癌模型与肝移植后肝癌复发转移模型中进行药效与机制研究，以明确外泌体miR-25-LATS2/KLF4信号在肝癌复发转移中的作用，并通过靶向性纳米药物的构建和应用研究，以期对移植术后肝癌复发转移实现有效防治。

Tumor recurrence or metastasis after liver transplantation (LT) for hepatocellular carcinoma (HCC) is the main factor that greatly impairs long term survival of transplant recipient. The discovery of recurrence or metastasis-related molecular markers and the early intervention by accurate targeted therapy will contribute to reducing HCC recurrent risk. The applicant’s previous study revealed that HCC patients with high expression of miR-25 in peripheral blood exosomes had elevated recurrent rate after LT. Besides, miR-25 could inhibit its downstream target LATS2 and enhance the proliferation and migration ability of HCC cells. Meanwhile, miR-25 was able to participate in tumor recurrence and metastasis by inhibiting KLF4 of vascular endothelial cells, but the specific mechanism of exosomal miR-25 in promoting HCC recurrence and metastasis remains to be further clarified. Based on these previously discovered targets, the applicant combines a nano-polyplex of B-PDEA/miR-25 inhibitor and in situ or metastatic HCC-targeting SP94 peptide or VEGFR2 antibody-decorated lipid, to construct ROS-reactive nucleic acid nanoparticles with tumor recurrent and metastatic foci-targeting ability. And the efficacy and mechanism will be further studied in HCC cells, vascular endothelial cells, mice in situ HCC model and mice model of HCC recurrence or metastasis after LT, by means of which, the specific role of exosome miR-25-LATS2/KLF4 signal in HCC recurrence and metastasis will be further identified. And the targeted nanoparticles will be constructed and applied, so as to efficaciously prevent or treat HCC recurrence or metastasis after LT.