经皮射频消融兔小腿VX2肿瘤前后对组织HSP70、IL-8表达的影响及意义

The impact and significance of HSP 70 and IL-8 expresion before and after percutaneous radiofrequency ablation on rabbit leg VX2 tumor tissue

目的观察经皮射频消融（RFA）治疗兔小腿VX2肿瘤前后其组织中热休克蛋白70（HSP70）及白介素8（IL-8）表达变化并探讨其免疫的影响。方法取体重约2．5～3．0kg的健康新西兰大白兔31只，以注射细胞悬液的方法分别建立肿瘤模型，模型经检测建立成功后，分为两组，其中实验组20只，对照组10只，静脉麻醉并CT定位病灶成功后，导入消融针消融5min，对照组只导入消融针不进行消融治疗，分别于RFA前及RFA后1、3、7、14天、5个时间点处死4只瘤兔（对照组2只），取消融灶（包含残余肿瘤组织）及消融灶周围5mm以外的正常组织2块标本，聚合酶链式反应（PCR）和免疫印迹（Western Blot）用来检测肿瘤组织HSP70和IL-8的表达。免疫组化检测HSP70的变化，同时观察两组动物肿瘤的大小变化。结果在正常组织中及瘤体组织中HSP70的表达在术后呈现相似的表达趋势，均于术后表达增多，两者均于RFA术后3天开始呈现明显的增多趋势，于7天达到峰值，14天略呈下降；PCR结果亦显示了与免疫组化相似的趋势，而IL-8在术后则表现为低表达的趋势，且在14天最为显著；Western Blot的蛋白定量检测显示，肿瘤组织内，在术前表达较少，在术后表达呈现与免疫组化、PCR相同的趋势，IL-8的表达亦与前相同。结论射频消融治疗肿瘤后，使肿瘤细胞坏死，HSP70表达增加，IL-8水平下降，此则与RFA破坏肿瘤组织，释放细胞因子、肿瘤特异性抗原等激发机体抗肿瘤免疫反应有关。

Objective To observe the changes of HSP70, IL-8 expression in rabbit VX2 tumor after radiofrequency ablation, and to discuss its means for immune responses. Methods Tumor model was established by injecting VX2 carcinoma ceil suspension into the rabbit legs in 31 healthy new zealand white rabbits （ weighs about 2.5 - 3.0 kg）. 30 rabbits were divided into two groups： 20 for RFA treatment group and 10 for control group. The control groups only inserted electrodes, with simulation treatment. Tissue samples were collected at 5 different time points, which were before and 1 st , 3 th, 7 th, 14 th days after RFA. At each time point, 4 rabbits were executed in the treatment group, while 2 in control group. HSPT0 of tumor tissues was examined by immunohistochemical examination. PCR and Western Blot were used to detect the expression of HSP70 and IL-8. At the same time, the tumor size was observed. Results In normal tissue and tumor tissue, expressions of HSP70 in postoperative presenting similar trends were increased after surgery, both at 3 d after RFA was beginning to show significant increasing trend, peaked at 7 d, 14 days slightly decreased; PCR result also showed a similar trend immunohistoehemistry, and IL-8 in the postoperative showed low expression, and in 14 days the most significant; Western Blot protein quantification revealed the tumor tissue in expressing less preoperative and postoperative and immunohistoehemical expression showing the same trend in PCR, the expression of IL-8 was also the same as before. Conclusion Radiofrequency ablation of tumor leads to tumor cell necrosis, increases HSP70 expression, decrease IL-8 level, which is related to the RFA destruction of tumor tissue, the release of eytokines, tumor-specific antigens stimulate anti-tumor immune response.