聚谷氨酸-顺铂复合物的制备及其生物活性

Preparation and biological activity of poly(γ-glutamic acid)-cisplatin conjugate

本文介绍了制备一种γ-聚谷氨酸-顺铂复合物，并考察其体外的抗肿瘤活性。主要通过生物发酵法获得γ-聚谷氨酸，酸降解法得到小分子γ-聚谷氨酸；利用PCR方法检测γ-聚谷氨酸．顺铂复合物对DNA的作用；利用MTT法来检测该复合物的体外抗肿瘤作用；利用流式细胞仪检测其对细胞凋亡的作用；利用小鼠体内实验检测其体内毒性作用。实验结果表明：成功获得γ-聚谷氨酸-顺铂复合物，该复合物载药率达10％～12％；该复合物对人肝癌细胞BEL7404、人非小细胞肺癌细胞H446和人结肠癌细胞RKO均具有显著的杀伤作用，能引起细胞凋亡（出现凋亡峰）；并且小鼠体内毒性试验表明该聚谷氨酸-顺铂复合物的毒性要比游离顺铂低。因此，γ-聚谷氨酸-顺铂复合物是一种有效的抗肿瘤药物，具有潜在的临床应用价值；生物发酵的γ-聚谷氨酸可用于药物载体，赋予药物新的特点。

Preparation of a poly（γ-glutamic acid）-cisplatin conjugate was introduced and its in vitro antitumor effect was investigated. Poly （γ-glutamic acids） was obtained by using fermentation methods. The hydrolyzed small molecular weight of poly （γ-glutamic acids） was prepared by acid hydrolysis. The interaction between poly（y-glutamic acids）-cisplatin conjugate （PGA-CDDP） and DNA was investigated by PCR model. MTT assay was used to investigate the in vitro anticancer activity of the conjugate. Apoptosis assay of the conjugate was investigated by FCM assay and the in vivo toxicity was also proceeded. The results showed that the poly （γ-glutamic acids）-cisplatin conjugate was obtained successfully and its yield is 10% - 12%. It has obvious antitumor effects on human liver tumor BEL7404 cells, human lung tumor H446 cells and human colon tumor RKO cells. At the same time, it also has apoptosis effects on the three kinds of tumor cell lines. The in vivo toxicity of PGA-CDDP was examined in normal mice and the results showed that the in vivo toxicity of this conjugate was significandy lower than that of free CDDP. In conclusion, the poly （γ-glutamic acids ）-cisplatin conjuate could be used as a potential clinic antitumor drug. The poly（γ-glutamic acids） obtained by fermentation can be used as a valuable drug carrier system.