双自杀基因联合Survivin反义寡核苷酸对结肠癌裸鼠的体内抑瘤作用

Antitumor effect of double suicidal gene and survivin ASODN on colon cancer in nude mice in vivo

目的研究VEGF启动子驱动的双自杀基因(Ad-VEGFP-CDglyTK)联合Survivin反义寡核苷酸对裸小鼠体内结肠癌移植瘤的抑瘤作用。方法建立裸小鼠人结肠癌模型,将24只成瘤后的裸小鼠随机分为4组(n=6):空白对照组,不施加任何处理;重组腺病毒组,注射重组腺病毒Ad-VEGFP-CDglyTK与前药氟胞嘧啶(5-FC)、更昔洛韦(GCV);Survivin反义寡核苷酸(Survivin ASODN)组,注射Survivin ASODN;基因联合治疗组,注射重组腺病毒Ad-VEGFP-CDglyTK与前药5-FC、GCV,同时注射Survivin ASODN。治疗后测定瘤重并计算肿瘤生长抑制率;将瘤组织进行HE染色;免疫组化检测微血管密度(MVD)。结果各组最终瘤重及肿瘤生长抑制率分别为:空白对照组516.58±10.58mg,0%;重组腺病毒组238.74±15.77mg,53.78%±3.12%;Survivin ASODN组225.61±13.47mg,56.23%±2.60%;基因联合治疗组63.70±3.41mg,87.66%±0.70%。空白对照组与其他3组有显著差异(P<0.05),基因联合治疗组与重组腺病毒组、Survivin ASODN组比较亦有显著性差异(P<0.05)。常规病理检查可见肿瘤细胞生长受抑制,特别是基因联合治疗组抑瘤作用最明显,肿瘤组织切片中可见片状坏死区,而且这些区域可见大量炎性细胞浸润。空白对照组、重组腺病毒组、Survivin ASODN组和基因联合治疗组MVD分别为19.25±3.19、11.33±2.46、10.42±2.35、3.33±1.56,空白对照组MVD明显高于其他3组(P<0.05),重组腺病毒组及Survivin ASODN组MVD均显著高于基因联合治疗组(P<0.05)。结论VEGF启动子驱动的双自杀基因和Survivin ASODN均具有一定的体内抑瘤作用,两者联合应用具有协同作用,对于肿瘤的抑制作用更加显著。

Objective To study the in vivo antitumor effect of double suicide gene driven by vascular endothelial growth factor （VEGF） promoter （Ad-VEGFP-CDglyTK） and survivin ASODN on colon cancer produced by transplantation of LoVo cell in nude mice. Methods The nude mice model of colon cancer was reproduced. Twenty four nude mice were randomly divided into four groups （6 each） ： control group, in which animals received no treatment; recombinant adenovirus group, in which animals were injected with Ad-VEGFP- CDglyTK and 5-FC/GCV; survivin ASODN group, in which animals received survivin ASODN injection; and combined gene therapeutic group, in which animals were injected with Ad-VEGFP-CDglyTK, 5-FC/C, CV and survivin ASODN. The final weight of tumors was compared and the suppression rates on tumor were calculated. Hematoxylin and eosin staining were performed for histological examination, and microvessel density （MVD） of tumor was detected by immunohistochemistry method. Results The final weight and the suppression rate on tumor in the four groups were as follows： control group, 516. 58±10. 58mg; recombinant adenovirus group, 238. 74±15. 77mg, 53. 78%± 3. 12% ; survivin ASODN group, 225. 61± 13.47mg, 56. 23% ±2. 60% ; and combined gene therapeutic group, 63. 70 ± 3. 41mg, 87. 66%±0. 70%. Significant differences were found between control group with the other three groups （P〈0. 05）. Significant differences were also found between combined gene therapeutic group with recombinant adenovirus group and survivin ASODN group （ P〈0. 05）. The pathological changes showed that tumor growth had been inhibited. A lamellar zone of necrosis and massive inflammatory cell infiltration were observed. The MVD of tumor in the four groups ranged in following order： 19.25±3. 19, 11.33±2. 46, 10. 42± 2. 35 and 3. 33±1.56. The MVD increased significantly in control group compared to the other three groups （P〈0.05）. The MVD of recombinant adenovirus group and survivin ASODN group were significantly higher than that of combined gene therapeutic group （ P〈0. 05）. Condusion Double suicidal gene driven by VEGF promoter and survivin ASODN have antitumor effect in vivo and combined gene therapy had stronger antitumor effect. Double suicidal gene driven by VEGF promoter and survivin ASODN have synergistic antitumor effect.