内皮抑素真核表达载体对移植性卵巢癌的抑制作用

Inhibitory effect of endostatin mediated by lipofectin on transplanted ovarian cancer

目的探讨脂质体介导的内皮抑素真核表达载体对裸鼠移植性卵巢癌的抑制作用。方法利用已构建的内皮抑素真核表达载体pVAX1sEn,在脂质体介导下转染卵巢癌细胞系3AO细胞,RTPCR技术检测3AO细胞中内皮抑素mRNA的表达,酶联免疫吸附实验(ELISA)法检测3AO细胞上清液中内皮抑素的水平,四甲基偶氮唑蓝(MTT)法检测3AO细胞上清液中的内皮抑素对脐静脉内皮细胞系ECV204细胞的抑制作用。将荷卵巢癌移植瘤裸鼠分为3组,pVAX1sEn治疗组、pVAX1对照组和生理盐水对照组,分别观察3组卵巢癌的生长情况。结果RTPCR技术检测结果显示,在610bp处有一内皮抑素mRNA的特异性条带;ELISA法检测结果显示,pVAX1sEn转染3AO细胞后其上清液中内皮抑素水平为(201±8)ng/ml;MTT法检测结果显示,pVAX1sEn转染3AO细胞后其上清液中的内皮抑素可有效抑制ECV204细胞的生长,最高抑制率为42%。pVAX1sEn治疗组肿瘤体积为(0.85±0.18)cm3,显著小于生理盐水对照组的(1.90±0.28)cm3和pVAX1对照组的(1.78±0.32)cm3(P<0.05)。肿瘤组织HE染色显示,pVAX1sEn治疗组肿瘤细胞坏死明显,而生理盐水对照组及pVAX1对照组肿瘤细胞生长旺盛。结论脂质体介导的pVAX1sEn瘤内注射可有效抑制卵巢癌移植瘤的生长。

Objective To study the inhibitory effect of endostatin mediated by lipofectin on transplanted ovarian cancer in nude mice. Methods Constructed recombinant vector pVAX1-sEn expressing human endostatin protein was transfected into ovarian cancer cell line 3AO by lipofectin. mRNA of endostatin was detected by RT-PCR. The expression of endostatin in supernatants was detected by enzyme-linked immunosorbent assay(ELISA). The inhibitory effect of pVAX1-sEn on endothelial cell line ECV-204 was detected by methyl thiazolyl tetrazolium(MTT). By use of lipofectin mediated pVAX1-sEn for intratumor injection, the inhibitory effect on growth of ovarian cancer was observed. Results The result of RT-PCR showed there was a specific band at 610 bp. The expression quantity of endostatin in transfected cell supernatant was (201±8) ng/ml by ELISA. MTT showed pVAX1-sEn transfected cell supernatant could effectively inhibit the growth of ECV-204, the highest inhibitory ratio was 42%. The tumor volumes in pVAX1-sEn treatment group was (0.85±0.18)cm^3,significantly smaller than that in normal saline control group(1.90±0.28)cm^3 and pVAX1 control group (1.78±0.32)cm^3 (P<0.05). HE stain in tumor tissue showed that there were obvious necrosis cells in the pVAX1-sEn treatment group, but there were flourishly growing tumor cells in pVAX1 and normal saline control groups. Conclusion pVAX1-sEn mediated by lipofectin can effectively inhibit the growth of ovarian cancer.