^(131)I标记曲妥珠单抗对高表达HER-2/neu人卵巢癌的体内外实验研究

Experimental study on the effects of ^(131)I-labeled trastuzumab on human ovarian carcinoma with high expression of HER-2/neu in vitro and in vivo

目的:观察131I标记的曲妥珠单抗(trastuzumab,商品名为Herceptin)在体内外,对高表达人表皮生长因子受体-2(human epidermal growth factor receptor-2,HER-2)/neu的人卵巢癌细胞的靶向治疗作用。方法:采用Iodogen法用131I标记Her-ceptin,制备获得131I-Herceptin。实验设131I-Herceptin与顺铂(cisplatin,DDP)联用组、131I-Herceptin组、Herceptin组、DDP组及空白对照组。MTT法检测各实验组中不同药物处理对人卵巢癌SKOV3细胞的生长抑制作用。成功种植人卵巢癌SKOV3细胞移植瘤后,将荷瘤裸鼠随机分为5组,每周经尾静脉用药,连续6周,每周测量1次小鼠肿瘤的长径、短径及体质量,用药结束1周后处死小鼠,计算抑瘤率;并且采用HE染色法观察肿瘤细胞凋亡的情况,TUNEL法检测肿瘤细胞的凋亡指数;最后采用免疫组织化学法检测肿瘤组织中p53和HER-2蛋白的表达情况。结果:131I-Herceptin组的体外细胞生长抑制率及体内抑瘤率明显高于Herceptin组及DDP组;131I-Herceptin与DDP联用具有协同作用,131I-Herceptin和DDP联用组的体内肿瘤细胞凋亡指数显著高于其他各实验组,其p53和HER-2蛋白表达率则下降。结论:131I-Herceptin在体内外均能有效抑制高表达HER-2的人卵巢癌细胞生长,且与DDP联用具有协同作用。推测其可能的机制为,131I-Herceptin除影响体内HER-2蛋白表达外,还能通过内照射产生细胞毒作用,并参与p53基因调控。

Objective：To evaluate the targeting therapeutic effect of ^131I-labeled trastuzumab（Herceptin） on human ovarian carcinoma with high expression of HER-2/neu in vivo and in vitro.Methods：Herceptin was labeled with 131I using Iodogen method to prepare ^131I-Herceptin.There were five groups including 131I-Herceptin plus cisplatin（DDP） group,^131I-Herceptin group,Herceptin group,DDP group,and 0.9% sodium chloride solution group.The inhibitory effects of different treatments on the proliferation of human ovarian carcinoma cell line SKOV3 were measured by MTT assay.The human ovarian carcinoma SKOV3 cells were implanted into nude mice and tumor-bearing nude mice were randomly divided into five groups.Drugs were injected into the tail vein of the nude mice once a week for six weeks.The size and weight of the tumor were measured every week and the mice were killed at week 1 after the treatment.The inhibitory rate of tumor growth was calculated and tumor apoptosis was observed by HE staining.The apoptotic index was determined by TUNEL staining.The p53 and HER-2 expressions in the xenografted tumors were analyzed by immunohistochemical staining.Results：The tumor inhibitory rate of SKOV3 cells was significantly higher in ^131I-Herceptin group than those in Herceptin group and DDP group in vivo and in vitro.There was a strong synergistic effect between ^131I-Herceptin and DDP.The apoptotic index was significantly increased and the expressions of p53 and HER-2 were markedly decreased in ^131I-Herceptin plus DDP group compared with other groups in vitro.Conclusion：^131I-Herceptin effectively inhibited the growth of human ovarian carcinoma with high expression of HER-2/neu in vivo and in vitro.Its therapeutic efficiency was enhanced by DDP.The action mechanism was associated with the regulation of HER-2 protein,cytotoxic effects induced by endogenous radiation,and regulation of p53 protein.