生物伪装共载药介孔硅纳米粒的构建及其逆转三阴性乳腺癌耐药性的研究

Multi-drug resistance is the main cause for relapse of triple negative breast cancer (TNBC), and the leading cause of death in patients. It is an intractable problem for clinical medication of TNBC. Drug delivery system has its unique advantages in terms of overcoming drug resistance of tumor. However, the targeting effect of drug delivery system is greatly limited due to the lack of varieties of receptors on the cells surface of TNBC and the elimination of nanoparticles by immune system. Based on our previous research foundation, in this project, we hypothesize that: the co-delivery of disulfiram and doxorubicin by iRGD inserted red blood cell membrane coated mesoporous silica nanoparticles (MSN) could effectively target TNBC by improving immune escape, and overcome drug resistance by inhibiting multi-drug resistance protein I. First, iRGD modified biological camouflage MSNs will be prepared and well characterized by electron microscope, light scattering and other technologies. In vitro, cell binding ability, cellular uptake mechanism and the effect of overcoming drug resistance will be systematically investigated. The biological camouflage effect of this drug delivery system will be illustrated by cellular uptake of mononuclear macrophages and evaluation of immune response. Finally, tumor targeting and therapy effect will be well evaluated in TNBC tumor-bearing mice. Once the project was implemented, it will provide new research ideas and experimental basis for the development of new targeted drugs of TNBC.

三阴性乳腺癌（TNBC）的耐药是其复发和患者死亡的主要原因，也是临床药物治疗的难点。尽管纳米递药系统在逆转肿瘤耐药方面有其独特优势，但因TNBC缺乏多种受体，加之纳米粒的体内免疫消除，极大地限制了纳米递药系统的靶向效果。因此，基于申请人前期研究基础，提出以下设想：将耐药蛋白抑制剂和化疗药物共载于介孔硅中，再将iRGD修饰的红细胞膜包被于载体表面进行生物伪装，有望实现TNBC的高效靶向并逆转其耐药。首先制备尺度可控的生物伪装纳米粒，采用电镜、光散射等多种技术系统表征其生物理化性能。深入研究载体的体外肿瘤细胞靶向性、胞内转运机制及其体外逆转耐药效果。通过单核巨噬细胞摄取、体内免疫应激效应，阐明载体理化性能与其生物伪装效果的相关性。在体建立异体移植瘤模型，利用多种成像技术，考察载体的体内肿瘤靶向性，并评价其体内逆转耐药的效果。本项目的实施可为TNBC靶向药物制剂的开发提供新的研究思路和实验依据。

三阴性乳腺癌（TNBC）的耐药是其复发和患者死亡的主要原因，也是临床药物治疗的难点。尽管纳米递药系统在逆转肿瘤耐药方面有其独特优势，但因TNBC缺乏多种受体，加之纳米粒的体内免疫消除，极大地限制了纳米递药系统的靶向效果。基于申请人前期的研究基础，本项目将化疗药物包载于介孔硅中，再将iRGD修饰的红细胞膜包被于载体表面进行生物伪装和肿瘤的高效靶向。首先，成功制备并表征了具有TNBC主动靶向的生物伪装纳米粒（iRGD-RM-(DOX/MSN)），径在160-180nm之间且具有良好的分散性；细胞毒性实验和溶血性实验初步表明iRGD-RM-(DOX/MSN)具有较好的细胞和血液相容性；血常规及脏器毒性实验发现该纳米粒具有良好的体内安全性。其次，通过血浆蛋白吸附和单核巨噬细胞摄取实验发现：生物伪装纳米粒可大大降低血浆蛋白吸附，同时降低单核巨噬细胞对纳米粒的摄取，阐明载体具有良好生物伪装效果。体外细胞摄取实验发现，iRGD修饰后可显著提高MDA-MB-231细胞对生物伪装载药纳米粒的摄取，同时通过MTT实验和肿瘤细胞凋亡实验证实iRGD修饰的生物伪装纳米粒能更高效的杀伤肿瘤细胞。最后，异体移植瘤模型发现iRGD-RM-(DOX/MSN)在体内具更强的抗肿瘤活性。. 综上所述，本研究证明了红细胞膜包被后的介孔硅纳米粒在一定程度上实现了体内的生物伪装，而iRGD的修饰可增强肿瘤靶向性，两者的有效结合可解决纳米粒免疫消除和高效靶向两难的问题。本研究研为TNBC的靶向治疗或靶向药物制剂的开发提供新的研究思路和实验依据。