转导人肿瘤坏死因子α基因对耐药性绒毛膜癌裸鼠移植瘤耐药性的逆转作用

In vivo reversal of multidrug resistance by transduction of human tumor necrosis factor-α into drug resistant cell line of choriocarcinoma

目的 探讨转导人肿瘤坏死因子α(tumornecrosisfactor α,TNF α)基因 ,对耐药性绒毛膜癌 (绒癌 )裸鼠移植瘤耐药性的逆转作用。方法 将绒癌细胞系JEG 3(A细胞系 )、耐药性绒癌细胞系JEG 3/VP2 (B细胞系 )和转导TNF α基因的耐药性绒癌细胞系JEG 3/VP2 /TNF α(C细胞系 )接种于裸鼠颈背部皮下 ,建立绒癌裸鼠移植瘤模型。每种细胞系移植瘤模型均分为对照组 (腹腔注入生理盐水 )和化学药物治疗 (化疗 )组 [腹腔注入鬼臼乙叉甙 (VP 1 6) ] ,观察移植瘤的生长特点、组织学结构以及对化疗药物的敏感性 ;用逆转录聚合酶链反应方法和免疫组织化学方法 ,检测转导TNF α基因的耐药性绒癌裸鼠移植瘤中多药耐药 (multidrugresistance ,MDR1 )基因在mRNA和蛋白水平表达的改变。结果 移植成瘤率均为 1 0 0 % ,潜伏期 1 0～ 1 4d ;移植瘤组织学特征符合绒癌特点 ;C细胞系移植瘤的生长速度最慢 ,明显低于A、B两个细胞系的生长速度 (P均 <0 0 5) ;C细胞系对照组裸鼠的移植瘤[体积 (4 2± 0 5)cm3,重量 (0 95± 0 1 2 )g]比B细胞系对照组 [体积 (7 9± 0 3)cm3,重量 (1 60± 0 0 6)g]明显减少 (P <0 0 5) ,应用同样剂量的化学药物作用后 ,C细胞系化疗组肿瘤的抑制率 (41 0 %～42 5 % )接近A细胞系化疗组

Objective To investigate in vivo reversal of multidrug resistance and biological properties of a drug resistant cell line of choriocarcinoma transduced by human tumor necrosis factor α(TNF α) gene via the establishment of its animal model Methods Choriocarcinoma cell line JEG 3, drug resistant choriocarcinoma cell line JEG 3/VP2, and human TNF α transduced drug resistant choriocarcinoma cell line JEG 3/VP2/TNF α were injected subcutaneously in the neck of nude mices Tumor size and weight were routinely measured, tumor histological structure was observed and its chemosensitivity was tested Expression of multidrug resistance(MDR1) mRNA was investigated using reverse transeription polymerase chain reaction(RT PCR) and P glycoprotein (P gp) expression was determined by immunohistochemistry with the monoclonal antibody MDR1 Results The rate of inoculation for all three tested cell lines was 100%, the latent period was 10 to 14 days Tumor growth rates and weights were significantly different among three cell lines ( P <0 05), with the lowest in JEG 3/VP2/TNF α cell line Tumor inhibition rate after treatment with etopside (VP 16) was significantly higher in JEG 3/VP2/TNF α(41.0%-42 5%) ( P <0 05), compared with JEG 3/VP2 (24 3%-28%), and similar to JEG 3 (46 7%-47 7%) Transduction and expression of human TNF α in drug resistant choriocarcinoma cell line JEG 3/VP2 was found to reverse MDR1 on the mRNA and P gp levels Conclusion Transduction and expression of human TNF α in drug resistant choriocarcinoma cell line JEG 3/VP2 can reverse expressions of MDR1 mRNA and P gp, enhance the susceptibility of the JEG 3/VP2 to the cytotoxic drugs, and lower its tumorigenesis