HSV-TK/GCV联合IL-2治疗舌癌移植瘤的机制探讨

Research of treatment for experimented human lingual squamous cell carcinoma by union treatment with HSV-TK and IL-2

目的:观察HSV-TK联合IL-2对舌癌细胞的生长抑制作用,并探讨HSV-TK与IL-2联合应用对舌癌抑制和杀伤的机制。方法:建立舌癌Tca8113移植瘤动物模型,采用HSV-TK联合IL-2对移植瘤进行体内转染,观察肿瘤生长情况。使用RT-PCR检测HSV-TK基因和IL-2基因的表达情况;应用流式细胞仪检测移植瘤的凋亡情况;采用免疫组化法检测移植瘤中CD4和CD8蛋白的表达情况。结果:移植瘤体积生长曲线表明TK组(C组)及TK联合IL-2组(D组)肿瘤的生长明显受到抑制。TK组抑瘤率为40.1%,TK联合IL-2组抑瘤率为80.2%。RT-PCR检测目的基因HSV-TK基因和IL-2基因已整合入肿瘤细胞中且稳定表达。流式细胞仪检测A组(对照组)和B组(病毒组)凋亡峰不明显,而C组和D组凋亡峰明显。对照组、病毒组、TK组、TK联合IL-2组凋亡率分别为(6.77±1.31)、(7.08±1.28)、(13.22±3.28)、(28.90±6.50)。除对照组、病毒组无明显差异(P>0.05),其他任2组之间比较均有显著性差异(P<0.01)。在TK联合IL-2组,肿瘤细胞周围有大量CD4和CD8阳性的淋巴细胞浸润。结论:HSV-TK和IL-2治疗后可显著抑制Tca8113移植瘤的生长。HSV-TK与IL-2基因联合应用,其治疗效果较单独应用HSV-TK明显提高。HSV-TK可明显杀伤Tca8113移植瘤细胞,而IL-2可以诱导机体抗肿瘤免疫反应。

Objective：To observe the depressing effects on tongue cancer by union treatment with HSV-TK and IL-2 and to discuss its depressing mechanism.Methods：Tca8113 lingual cancer animal models were set up.In vivo experiment was done on planting tumors with HSV-TK and IL-2 gene.The tumor volumes were measured from the beginning of the experiment.Expressions of HSV-TK and IL-2 gene were detected by RT-PCR.The percentage of apoptotic cells was detected by flow cytometer.Immmunohistochemistry against CD4 and CD8 antibodies were also investigated.Results：From the growth curve of volume change of transplanted tumors,the growth of the transplanted tumors in TK group and TK/IL-2 group was inhibited.The ratio of tumor inhibition of TK group was 40.1% and that of TK/IL-2 group was 80.2%.Results of RT-PCR showed that HSV-TK gene and IL-2 gene had been transferred into tumor cells and expressed.Results of flow cytometer showed that typical apoptotic peak was formed in TK and TK/IL-2 groups.The percentage of apoptotic cells：（6.77±1.31）% in control group,（7.08±1.28）% in empty virus group,（13.22±3.28）% in TK group,and（28.90±6.50）% in group TK/IL-2 group.There was significant difference between groups（P〈0.01）,except group A and B（P〉0.05）.In TK/IL-2 group,many lymphocytes with CD4 and CD8 positive around tumor cells were found.Conclusion：HSV-TK/GCV system and IL-2 could suppress the growth of Tca8113 transplanted tumors in the nude mice.The effect of HSV-TK with IL-2 on Tca8113 transplanted tumors was better than that of HSV-TK/GCV alone.HSV-TK/GCV system can kill Tca8113 cells and IL-2 could induce immunologic reaction against tumor.