目的:建立人大肠癌LS-174T细胞的裸鼠皮下移植瘤模型,应用Skp2基因特异性siRNA重组腺病毒治疗,观察其在体内对肿瘤生长和转移的影响,并探讨其相应的作用机制。方法:将大肠癌LS-174T细胞以5×106个/只接种于雌性裸鼠右侧腋窝皮下,待平均瘤体积长至50~150mm3时筛选成模动物分组给药,分别给予重组腺病毒pAD-Skp2/siRNA 5×108和5×109pfu/只瘤内注射,阳性组给予今又生5×109pfu/只瘤内注射,另设空病毒对照组。每周给药2次,连续4周,以安乐死时肿瘤体积大小和重量来评价治疗效果。然后用Western Blot检测肿瘤组织中Skp2、p27kip1、c-myc、Bcl-2的表达,用免疫组化法检测肿瘤组织中MMP-2的表达。结果:安乐死时阴性对照组平均肿瘤体积与空病毒对照组生长情况基本一致(P≥0.05);今又生组平均肿瘤体积明显小于模型组(P≤0.05);pAD-Skp2/siRNA低、高剂量组平均瘤体积均显著低于模型组(P≤0.01),且有剂量依赖性。今又生组瘤重抑制率为58.16%,pAD-Skp2/siRNA低、高剂量组瘤重抑制率分别为75.59%、86.45%。Skp2蛋白表达在模型组、空病毒对照组和今又生组均有较强表达,而在pAD-Skp2/siRNA低剂量和高剂量组均未见表达;而p27kip1仅在pAD-Skp2/siRNA低剂量和高剂量组有表达,其余三组均未见其表达;c-myc和bcl-2表达趋势一致,均在模型和空病毒对照组有表达,而在今又生组和pAD-Skp2/siRNA两个剂量组均表达明显减弱。模型组和空病毒对照组有棕黄色阳性表达,而今又生组和pAD-Skp2/siRNA两个组均未检测到MMP-2阳性表达。结论:在高转移性大肠癌LS-174T裸鼠移植瘤模型中,封闭Skp2基因可以抑制肿瘤的增殖和转移,其作用机制与细胞周期调控、细胞凋亡中的c-myc和bcl-2以及基质金属蛋白酶MMP-2相关。 OBJECTIVE: To establish a subcutaneous xenograft tumor model of human colorectal cancer LS-174T cells in nude mice and to observe its effect on tumor growth and metastasis by using Skp2 gene-specific siRNA recombinant adenovirus and to explore its corresponding mechanism. Methods: Colorectal cancer LS-174T cells were inoculated into the right armpit of female nude mice subcutaneously at 5 × 106 cells. When the average tumor volume was up to 50-150 mm3, the animals were screened and the animals were divided into groups. The recombinant adenovirus pAD -Skp2 / siRNA 5 × 108 and 5 × 109pfu / intratumoral injection, the positive group given this again 5 × 109pfu / only intratumoral injection, another set of empty virus control group. Administered twice a week for four consecutive weeks, euthanasia tumor size and weight to evaluate the therapeutic effect. The expression of Skp2, p27kip1, c-myc and Bcl-2 in tumor tissues was detected by Western Blot. The expression of MMP-2 in tumor tissues was detected by immunohistochemistry. Results: The average tumor volume of negative control group was basically the same as that of empty virus control group (P> 0.05) at euthanasia; mean tumor volume of present-day group was significantly lower than that of model group (P≤0.05); low and high pAD-Skp2 / The mean tumor volume in the dose group was significantly lower than that in the model group (P≤0.01), and it was dose-dependent. The present tumor weight inhibition rate was 58.16%, pAD-Skp2 / siRNA low, high dose group tumor weight inhibition rates were 75.59%, 86.45%. Skp2 protein expression was strongly expressed in model group, empty virus control group and present-day regenerative group, but not in pAD-Skp2 / siRNA low-dose and high-dose groups; p27kip1 was only expressed in low pAD-Skp2 / siRNA The expression levels of c-myc and bcl-2 were the same in model group and empty virus control group, while the expression of c-myc and bcl- siRNA expression in both groups were significantly reduced. The model group and the empty virus control group had a positive expression of brown, but no positive expression of MMP-2 was detected in the present regenerative group and the pAD-Skp2 / siRNA two groups. Conclusion: In the metastatic colorectal cancer LS-174T model in nude mice, blocking the Skp2 gene can inhibit the proliferation and metastasis of the tumor. Its mechanism is related to cell cycle regulation, c-myc and bcl-2 in apoptosis and Matrix metalloproteinase MMP-2 is associated.