HSV-tk/CD融合基因杀伤人胆管癌细胞QBC939的体内实验

In Vivo Antitumor Activity of HSV-tk/CD Combinative Gene Toward Human Cholangiocarcinoma Cells(QBC939)

目的研究单纯疱疹病毒胸苷激酶(HSV-tk)/胞嘧啶脱氨酶(CD)融合基因在动物体内对人胆管癌的杀瘤作用。方法构建人胆管癌的裸鼠皮下移植瘤动物模型,按排序法随机分为4组,每组8只。对照组,每只裸鼠腋部瘤体内注入不含自杀基因的腺病毒液0.1 ml,CD基因组t、k基因组和HSV-tk/CD融合基因组,在每只裸鼠腋部瘤体内分别注入CD基因t、k基因及HSV-tk/CD融合基因的重组腺病毒液0.1 ml。注射后24 h每只裸鼠腹腔内注射5-氟胞嘧啶(5-flurocytosine,5-FC)和丙氧鸟苷(ganciclovir,GCV),观察肿瘤的生长情况。结果CD基因组t、k基因组及HSV-tk/CD融合基因组肿瘤的生长均受到不同程度的抑制,与对照组比较,抑制率分别为41.2%、55.7%和70.7%,P均<0.05;病理组织学检查显示,对照组肿瘤生长良好,细胞分裂相多见;其余各组出现不同程度的肿瘤坏死,这种现象以HSV-tk/CD融合基因组最为明显。结论HSV-tk/CD融合自杀基因在胆管癌细胞体内也具有较强的杀瘤活性,但作用不够彻底,可能与旁观者效应(bystander effect,BSE)的效应强度有关。

Objective To study the antitumor activity of HSV-tk/CD combinative gene toward human cholangiocarcinoma in vivo. Methods Nude mouse models with transplanted subcutaneous cholangiocarcinoma were constructed and divided into 4 groups randomly, each group had 8 mice. Adenovirus solution free from suicide gene was injected in subcutaneous tumors of each mouse of control group. Adenovirus solution containing cytosine deaminase （CD）, thymidine kinase （tk） and HSV-tk/CD fusional gene were injected into single suicide gene either HSV-tk or CD was transinfected into the tumor cells by injecting viras into subcutaneous tumor of mice of CD gene, tk gene and fused CD and tk gene group respectively. 24 hours after the injection, 5-fluorocytosine （5-FC） and ganciclovir （GCV） were injected introabdominally in each mouse. Growth of the tumors were monitored. Results Tumor growth of the gene-transfection groups was suppressed in different degrees. Compared with the control group, the suppressing rates of the gene-transfection groups were 41.2%, 55.7% and 70.0% respectively （P〈0.05）. Histological examination showed good tumor growth in the control group, and tumor necrosis in the other 3 groups, particularly obvious in the group transfected with pAd （HSV-tk/CD）. Conclusion Combinative gene system has a strong antitumor effect on cholangiocarcinoma in vivo. But it＇s not powerful enough to eliminate tumor thoroughly because of insufficient “Bystander effect”.