低分子量鱼精蛋白介导的天花粉蛋白的抗肿瘤应用

Study on Anti-tumor Activities of Trichosanthin Mediated by Low Molecular Weight Protamine

【目的】研究重组穿膜肽天花粉蛋白的抗肿瘤作用。【方法】利用蛋白重组技术,在天花粉蛋白的C端引入半胱氨酸,并以此作为修饰位点偶联穿膜肽,通过亲和色谱法分离纯化得到目的蛋白。以十二烷基硫酸钠—聚丙烯酰胺凝胶电泳检测目的蛋白的生成以及其对还原性物质的响应性。通过细胞摄取实验研究穿膜肽介导蛋白内吞摄取效率,采用四甲基偶氮唑盐(MTT)法,测定穿膜肽天花粉蛋白修饰物的抗肿瘤活性。【结果】成功制备穿膜肽—天花粉蛋白复合物,此复合物具有一定还原响应性。且经过穿膜肽修饰后,天花粉蛋白在HeLa、MCF-7肿瘤细胞的摄取率明显增强,对HeLa、MCF-7细胞的抗肿瘤作用也显著提高。【结论】穿膜肽修饰天花粉蛋白可显著提高其抗肿瘤作用。

Objective To investigate the anti-tumor activities of cell-penetrating peptide （CPP） - mediated trichosanthin （TCS） , which is a recombinant protein obtained from Radix Trichosanthis. Methods Cysteine residue was introduced to the C-terminus of TCS by protein recombinant technique, and then with the newlyformed terminal as the modification site, TCS was coupled with CPP. As a target protein, CPP-mediated TCS was isolated and purified by affinity chromatography. The expression of the target protein and its responsiveness to reducing substances were detected by using the sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The cellular uptake rate of CPP-mediated TCS was determined by using cell uptake test, and its anti-tumor activity was measured by using methyl thiazolyl tetrazolium （MTT） assay. Results The TCS-CPP compound had been successfully developed in this study, and showed certain reducing responsiveness. After modified with CPP, TCS had higher cellular uptake rate and stronger anti-tumor effect on HeLa and MCF-7 cells. Conclusion TCS modified by CPP can enhance the anti-tumor activities of TCS.