雷公藤甲素共载miRNA-497抗卵巢癌耐药及调控巨噬细胞协同效应的机制研究

Inhibition of drug resistance and anti-tumor immune response play a decisive role in the treatment of ovarian cancer. Our published articles and preliminary experiments have shown: 1. The immune pattern of the ovarian cancer patients changes dynamically with the chemotherapy cycle when they receive first-line chemotherapy. There is potential mutual regulation between tumor-associated macrophages (TAMs) in immune microenvironment and drug-resistant ovarian cancer.2. Tripterygium wilfordii (TP) can promote the differentiation of TAMs to M1 type and inhibit the expression of PD-L1. 3. miRNA-497 is expressed at low level in drug-resistant ovarian cancer cell lines, and TP can reduce mTOR protein so as to inhibit drug resistance. Herein, we put forward the scientific hypothesis that TP can regulate the tumor immunization microenvironment through regulating TAMs, and generate synergistic effect with miRNA-497 in treating resistant ovarian cancer. In this project, a tumor targeting drug delivery system, TP/miRNA-497 external secretory is constructed and study the molecular, cellular and animal’s mechanisms on the regulation of TAMs in drug resistant ovarian cancer. Moreover, the synergistic mechanism of TP combined with miRNA-497 to inhibit multidrug resistance of ovarian cancer is identified through investigating P13K-AKT-mTOR and other different signaling pathways. In addition, expected results can achieve a new strategy for the treatment of drug-resistant ovarian cancer, along with the dual effects of inhibiting drug resistance and regulating the tumor immunity.

抑制耐药和抗肿瘤免疫反应在卵巢癌治疗中发挥决定性作用。申请人前期研究发现:1.卵巢癌患者接受一线化疗时,机体的免疫格局随化疗周期发生动态变化,耐药卵巢癌与免疫微环境中肿瘤巨噬细胞(TAMs)发生潜在的相互调控2.雷公藤甲素(TP)可促进TAMs向M1型分化,抑制PD-L1表达3.miRNA-497在耐药卵巢癌细胞株中低表达,TP可协同下调mTOR蛋白抑制耐药。因此我们提出“TP可通过TAMs调控肿瘤免疫微环境,在抑制耐药上可能与miRNA-497具有协同作用”的科学假说。本课题拟构建外泌体共载TP/miRNA-497,从分子、细胞、动物水平研究TP对耐药卵巢癌TAMs的调控,阐明其调控肿瘤微环境的作用机制;从P13K-AKT-mTOR等不同信号通路着手，明确TP联合miRNA-497对抑制卵巢癌耐药的协同效应机制。实现抑制耐药和调控肿瘤免疫双重作用的耐药卵巢癌治疗新策略。

卵巢癌是女性易患的第二大妇科肿瘤，由于缺乏早期诊断措施，大多数患者被确诊时肿瘤已经进展至中晚期阶段，其致死率排在妇科肿瘤中的第一位。多年以来，手术切除肿瘤病灶，辅助以化疗是卵巢癌的经典治疗方式。经典化疗药物顺铂通过与肿瘤细胞内 DNA 相互作用形成链内交联加合物，从而活化促凋亡信号通路诱导卵巢癌细胞亡，提高了卵巢癌患者的生存率。然而，在卵巢癌经过顺铂化疗后，肿瘤患者产生了广泛的顺铂耐药，继续使用顺铂治疗卵巢癌难以获得令人满意的治疗效果，因此迫切需要开发新的治疗策略来提高卵巢癌的治疗效率。雷公藤甲素（Triptolide，TP）与 microRNA-497（miR497）在耐药性卵巢癌的临床应用中非常有前景。针对卵巢癌患者在临床治疗中所面临的困难，本课题应用纳米递送系统在多种肿瘤治疗中的迅速发展，制备了共载 miR497 和 TP 的外泌体-脂质体杂合纳米载药系统，该纳米载药系统联合化疗和基因治疗通过多种途径来克服卵巢癌耐药。此外，我们制备的杂合纳米载药系统，在提高药物治疗效率的同时还能降低药物的全身毒副作用。