WTp53基因联合双自杀基因介入途径治疗肝癌的实验研究

The experimental study of wild-type p53 and double suicide gene for interventional therapy in liver carcinoma

目的探讨经介入途径多疗法、多基因联合治疗肝癌的可行性。方法分别制备pCMV-p53质粒-脂质体复合物及浓缩的TK-CD逆转录病毒上清。新西兰大白兔50只建立兔肝癌模型。根据B超及CT扫描结果，选取肿瘤直径约2cm的荷瘤兔45只，随机分为5组，每组9只。第1组为单纯生理盐水治疗组（对照组）；第2组为单纯超液化碘油栓塞组；第3组为超液化碘油＋p53组；第4组为超液化碘油＋TK／CD组；第5组为超液化碘油＋p53＋TK／CD组。经股动脉肝动脉插管成功并造影确定靶血管后，1.2F微导管超选择插管至肿瘤供血动脉，透视监视下按分组缓慢灌注实验药品。各组瘤兔分别于介入术前、术后10d行B超和CT扫描，检测肿瘤最大径（a）和最小径（b），计算肿瘤体积（V=ab^2／2）及肿瘤生长率。介入手术后8周，动物脱颈处死（包括观察期内自然死亡的），行常规病理检查及生存期的观测。结果成功建立兔肝癌模型，插管及介入治疗顺利。治疗前各组肿瘤体积无统计学差异（P〉0．05）。介入治疗后10d对肝脏肿瘤体积变化进行分析显示，与对照组比较，各治疗均对肿瘤的生长具有显著抑制作用（P〈0．05），其中碘油栓塞＋联合基因治疗组的效果最为显著。2×2析因分析表明：p53基因、TK／CD基因与碘油栓塞结合均有明显的抑制肿瘤生长的作用，但二者之间无交互协同作用（P=0．793）。与对照组比较各治疗组动物生存期延长，差异均有统计学意义（P〈0．01），其中多疗法、多基因联合治疗组效果最为明显。结论介入疗法可以为基因治疗提供理想的给药方法及途径。碘油栓塞、WTp53基因与TK／GCV、CD／5-Fc系统联合应用可以有效抑制肿瘤生长，延长动物生存期。

Objective To investigate interventional procedures and polygene feasibility for the treatment of liver carcinoma. Methods pCMV-p53 plasmid-liposome complex and concentrated TK CD retrovirus of supernatant liquid were prepared along with rabbit VX2 liver tumor models of 50 adult New Zealand rabbits. VX2 liver tumors about 2 cm in diameter from 45 adult rabbits were randomly divided into 5 groups of 9. Group 1 was the control group that used 0.9 % sodium chloride as a placebo. Group 2 had transcatheter arterial embolization with [ipiodol as treatment. Group 3 was the lipiodol and p53 group. Group 4 was the lipiodol and TK/CD group. Group 5 was the lipiodol, p53, and TK/CD group. The microtubule（1.2f）was inserted from the femoral to hepatic artery, tumor supply arteries were demonstrated by angiograms, and the drug was slowly injected under x-ray. The VX2 liver tumors were examined with B-ultrasound and computed tomography for maximum diameter （a） and minimum diameter （b） before and 10 days after interventional therapy. Gross tumor volume （V= ab2/2） and tumor growth rate were calculated. All the adult rabbits were euthanized 8 weeks after interventional therapy （including natural deaths）. Histopathological examination was taken and survival time was observed. Results The tumor volume among the 5 groups had no significant difference before interventional therapy （P〉0.05）. Ten days after interventional therapy, analysis of the tumor volume for variance and the Ttest were carried out. The results showed that each group compared to the control showed a significant difference in inhibiting cancer growth （P〉0.05）. The lipi-odol, p53, and TK/CD group showed the best effect. According to factorial statistic analysis （2×2）, p53 or TIK/CD combined with lipiodol therapy can control the tumor obviously, but no mutual synergism effect was found （P=0. 793）. Each treatment group showed a significant difference of prolonged survival time compared to the control group （P〉0. 01）. The multireatment or multi-gene group showed the best curative effects. Conclusions Interventional therapy can be the ideal path for admin istering medications for gene therapy. Transcatheter arterial embolization with lipiodol, wild-type p53 gene, TK/GCV, and CD/5-Fe applied in combination can control tumor growth and prolong survival time.