细胞膜穿透肽TAT修饰抗癌肽HPRP-A1提高其抗癌选择性的研究

发布时间：2017-12-31 19:18

本文关键词：细胞膜穿透肽TAT修饰抗癌肽HPRP-A1提高其抗癌选择性的研究　出处：《吉林大学》2016年硕士论文　论文类型：学位论文

【摘要】：HPRP-A1是一种来自幽门螺旋杆菌核糖体蛋白L1(Rp L1)N端的α-螺旋抗癌肽。在本课题组前期的研究工作中已经证实,抗癌肽HPRP-A1既可以通过死亡受体介导的外源途径诱导He La细胞凋亡,又可以通过线粒体介导的caspase依赖性内源途径诱导He La细胞凋亡。在本研究中,我们将细胞穿透肽TAT与抗癌肽HPRP-A1的C端进行偶联得到一种新的杂合肽,即HPRP-A1-TAT。与亲本肽HPRP-A1相比,杂合多肽HPRP-A1-TAT对He La细胞表现出更高的抗癌活性,同时对人血红细胞具有更低的溶血毒性,进一步提高了其抗癌选择性。同时,我们利用化学合成方法将FITC标记在多肽的氨基端(FITC-HPRP-A1和FITI-HPRP-A1-TAT),并通过激光共聚焦显微镜观察和流式细胞仪检测等方法对两种多肽进入细胞的过程和机制进行探究。实验证实,与亲本肽HPRP-A1相比,杂合肽HPRP-A1-TAT可以更快速地通过胞吞和破膜两种方式穿过细胞膜,进入到细胞质中。在同等浓度时,HPRP-A1-TAT具有更高的抗癌活性,并且可以诱导更多的He La细胞产生早期凋亡,同时激活caspase蛋白酶活性。此外,多肽样品加入He La细胞作用24h后,细胞中HPRP-A1-TAT的含量要明显高于HPRP-A1。我们推测,可能是因为TAT具有更多阳离子氨基酸,对HPRP-A1有一定的保护作用,使其在细胞质中降解缓慢,或是TAT-HPRP-A1可以通过胞吞形式进入细胞内,从而使其对HPRP-A1具有一定的保护作用。本课题对HPRP-A1-TAT的抗癌作用机理进行了初步探究,经过TAT修饰的抗癌肽可以提高其活性,降低毒性,同时提高其治疗指数,为抗癌肽在临床中的应用提供了一种更好的策略和方向。
[Abstract]:HPRP-A1 is a kind of Helicobacter pylori ribosomal protein L1 (Rp L1) N terminal alpha helix anticancer peptides in this research. The group has confirmed that both HPRP-A1 anticancer peptides can induce apoptosis in He La cells by exogenous death receptor-mediated pathway, but also through the mitochondria mediated caspase dependent the endogenous pathway induced apoptosis of He La cells. In this study, we will cell penetrating peptide TAT and anticancer peptide HPRP-A1 C end was obtained by coupling a new hybrid peptide, compared to HPRP-A1-TAT. and peptide HPRP-A1, heterozygous He polypeptide HPRP-A1-TAT on La cells showed higher antitumor activity and hemolytic toxicity at the same time, the red blood cells in human blood is lower, to further enhance its antitumor selectivity. At the same time, we use the method of chemical synthesis of FITC markers in polypeptide amino terminal (FITC-HPRP-A1 and FITI-HPRP-A1-TAT), and by laser scanning Confocal microscopy observation and flow cytometry method to explore into the process and mechanism of cell of two polypeptide. Experiments show that compared with the parent peptide HPRP-A1, hybrid peptide HPRP-A1-TAT can more quickly across the cell membrane by endocytosis and membrane rupture in two ways, into the cytoplasm at the same concentration. When the HPRP-A1-TAT has higher antitumor activity and can induce more He La cells produced early apoptosis, and activation of caspase protease activity. In addition, adding He peptide samples La cells after 24h, HPRP-A1-TAT content in the cells to be significantly higher than the HPRP-A1., we speculate that may be because TAT has more cationic amino acids, protection effect on the HPRP-A1, the degradation in the cytoplasm is slow, or TAT-HPRP-A1 can enter cells via endocytosis, thus it has a protective effect on the HPRP-A1. The mechanism of anticancer action of HPRP-A1-TAT has been preliminarily studied. TAT modified anticancer peptide can improve its activity, reduce toxicity and improve its therapeutic index, providing a better strategy and direction for anticancer peptides in clinical application.

【学位授予单位】：吉林大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：R730.5

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