iNGR多肽介导的靶向脂质体递药系统用于脑胶质瘤治疗的研究

发布时间：2018-05-29 14:43

本文选题：CD13 + 神经胶质瘤　；参考：《华东师范大学》2017年硕士论文

【摘要】：脑胶质瘤是一种发生于颅内的恶性肿瘤,特别是神经胶质瘤在临床上的治疗效果非常的不乐观,在胶质瘤发病人群中,5年的存活率仅为9.8%,并且患者的生活质量非常低。近年来,研究治疗脑胶质瘤的药物成为了医学上的难点和热点。目前主要通过手术以及化疗和放疗来治疗,化疗药物主要有替莫唑胺,丙戊酸和开普兰等,日本学者有应用干扰素对其进行治疗,但单纯的化疗对于治疗效果不是特别理想。因此,研发出针对脑胶质瘤的化疗药物是一项富有挑战性的工作。近年来,纳米递药系统有了很快的发展,各种高分子纳米药物也不断增加研发比例。主动靶向纳米药物递送系统的抗肿瘤效应在体内递送中受到肿瘤血管屏障和肿瘤基质屏障的阻碍。在这项研究中,为了克服两个障碍,我们使用iNGR,一种肿瘤穿透肽,修饰脂质体增加其在肿瘤组织中的积累和渗透。iNGR的结构由血管回归基序,组织穿透基序(R/KXXR/K)和蛋白酶识别位点组成。一方面,它可以明确地识别由胶质瘤新生血管内皮细胞过度表达受体CD13,特别是在病理状态。另外,它可以在肿瘤附近通过特异性酶切割成iNGRt肽(CRNGR序列),其可以特异性穿透肿瘤血管并进入深部肿瘤组织,并被胶质母细胞瘤细胞内化。该功能基于iNGRt与其受体NRP-1在肿瘤血管和胶质细胞瘤细胞上的特异性相互作用。因此,肿瘤血管靶向和肿瘤穿透能力可能使iNGR能够克服肿瘤血管屏障和肿瘤基质屏障。本论文第一章节首先合成了 iNGR-DSPE-PEG目标导向化合物,并制备iNGR-修饰的脂质体(iNGR-LS),其显示约1OOnm的粒径,且分布均一。论文第二章通过细胞体外实验表明了 iNGR-LS表现出比未修饰的脂质体(LS)显着增加了 U87MG肿瘤细胞和HUVEC的细胞内化,增加了肿瘤细胞的摄取。与普通的多柔比星脂质体(LS/DOX)相比较,iNGR多肽修饰的DOX脂质体(iNGR-LS/DOX)对U87MG和HUVECs细胞的毒性显著增加。论文第三部分通过体内成像研究证实iNGR修饰显着增加脑胶质瘤动物模型中的脂质体积累和渗透。免疫荧光染色分析证实了 iNGR-LS可以穿透肿瘤血管壁且进入肿瘤组织。iNGR-LS/DOX 还显示出比 LS/DOX(p0.05)更强的对肿瘤的生长抑制作用,这应该归因于由iNGR介导的增加的肿瘤积累和穿透效果。这项研究证明iNGR肽修饰可能是改善脂质体在肿瘤组织中的运输和增强其抗肿瘤效果的有效策略。
[Abstract]:Glioma is a malignant tumor occurring in the brain, especially glioma. The clinical therapeutic effect of glioma is not optimistic. The 5-year survival rate of glioma patients is only 9.8, and the quality of life of the patients is very low. In recent years, research on the treatment of glioma drugs has become a difficult and hot point in medicine. At present, it is mainly treated by surgery, chemotherapy and radiotherapy. The main chemotherapeutic drugs are temozolamide, valproic acid and Kaplan. Japanese scholars have used interferon to treat them, but chemotherapy alone is not particularly effective. Therefore, developing chemotherapeutic drugs for gliomas is a challenging task. In recent years, nanodelivery system has a rapid development, a variety of polymer nanopharmaceuticals are also increasing the proportion of research and development. The antitumor effect of active targeting nanopharmaceutical delivery system is hindered by tumor vascular barrier and tumor matrix barrier in vivo. In this study, to overcome two obstacles, we used iNGR, a tumor penetrating peptide, to modify liposomes to increase its accumulation in tumor tissues and osmotic. Tissue penetrating motifs R / K XXR / K) and protease recognition sites. On the one hand, it can clearly recognize the overexpression of CD13 receptor by glioma neovascularization endothelial cells, especially in pathological state. In addition, it can be dissected by specific enzyme in the vicinity of tumor to form iNGRt peptide CRNGR sequence. It can penetrate tumor blood vessels and enter deep tumor tissue, and be internalized by glioblastoma cells. This function is based on the specific interaction of iNGRt and its receptor NRP-1 on tumor blood vessels and glioma cells. Therefore, tumor vascular targeting and tumor penetration may enable iNGR to overcome tumor vascular barrier and tumor matrix barrier. In the first chapter of this thesis, iNGR-DSPE-PEG target oriented compounds were synthesized and iNGR- modified liposome iNGR-LSN was prepared, which showed the size of 1OOnm and its distribution was uniform. In chapter 2 the results of in vitro cell experiments showed that iNGR-LS significantly increased the cellular internalization and uptake of U87MG tumor cells and HUVEC cells as compared with the unmodified liposome LSs. Compared with the normal doxorubicin liposome LS / DOX, iNGR polypeptide modified DOX liposome (iNGR-LS / DOX) significantly increased the toxicity of iNGR-LS / DOX to U87MG and HUVECs cells. In the third part iNGR modification significantly increased the accumulation and permeability of liposome in glioma animal model by in vivo imaging. Immunofluorescence staining confirmed that iNGR-LS could penetrate the vascular wall of tumor and enter tumor tissue. INGR-LS- / DOX also showed a stronger inhibitory effect on tumor growth than LS- / DOXP0.05, which should be attributed to the increased tumor accumulation and penetrating effect mediated by iNGR. This study suggests that iNGR peptide modification may be an effective strategy for improving the transport of liposomes in tumor tissues and enhancing their antitumor effects.
【学位授予单位】：华东师范大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：R943;R96

【参考文献】