慢病毒介导的VCAM-1基因沉默对人舌鳞癌裸鼠移植瘤生长的影响

Effect of VCAM-1 gene silencing mediated by lentiviral vector on growth of xenograft tumors of human tongue squamous cell carcinoma in nude mice

目的:探讨慢病毒介导的血管细胞黏附分子1(vascular cell adhesion molecule-1,VCAM-1)基因沉默对裸鼠体内人舌鳞癌细胞移植瘤生长的抑制作用。方法 :构建人舌鳞癌Tca-8113细胞的裸鼠皮下移植瘤模型,随机分为干扰组、阴性对照组和空白对照组,分别瘤内注射含VCAM-1-sh RNA的慢病毒颗粒、含无关序列的慢病毒颗粒或0.9%氯化钠溶液。然后,观察移植瘤的生长情况,绘制移植瘤生长曲线。注射3周后处死裸鼠,称量各组移植瘤质量,并计算抑瘤率。采用HE染色法观察各组移植瘤细胞形态学特征;免疫组织化学法检测移植瘤组织中VCAM-1蛋白的表达水平以及肿瘤微血管密度(microvessel density,MVD),并分析二者之间的相关性。结果 :干扰组裸鼠移植瘤的生长速度明显小于阴性对照组和空白对照组(P值均<0.05),抑瘤率可达50.0%。3组裸鼠移植瘤组织切片均符合鳞状细胞癌的特征,无明显差异。干扰组移植瘤组织中VCAM-1蛋白的相对表达量及MVD值均明显低于阴性对照组和空白对照组(P值均<0.01)。VCAM-1蛋白表达与MVD呈正相关性(r=0.834,P<0.05)。结论 :慢病毒介导的VCAM-1-sh RNA干扰能通过沉默荷人舌鳞癌细胞裸鼠移植瘤中VCAM-1基因的表达,抑制移植瘤生长及血管生成,提示VCAM-1有望成为口舌腔鳞癌基因治疗的新靶点。

Objective： To investigate the inhibitory effect of vascular cell adhesion molecule-1 （VCAM-1） gene silencing on the growth of xenograft tumors of human tongue squamous cell carcinoma in nude mice.Methods： Murine subcutaneous xenograft tumor models of human tongue squamous carcinoma Tca-8113 cells were established in nude mice. The mice were randomly divided into three groups： interference group [injected with lentiviral particles of small hairpin RNA （shRNA） targeting VCAM-1 gene （VCAM-I-shRNA） into xenograft tumors], negative control group （injected with lentiviral particles of scramble RNA） and blank control group （injected with normal saline）. Then the tumor growth in nude mice was observed, and the tumor growth curve was drafted. After injection for 3 weeks, all of the mice were sacrificed, then the xenograft tumors were removed and the weight of the tumor was measured. The tumor inhibitory rate was calculated. The morphological features of xenograft tumors were observed by HE staining. The expression level of VCAM-1 protein and the microvessel density （MVD） of tumor tissues were detected by immunohistochemistry method. The correlation between VCAM-1 expression and MVD was analyzed.Results： The growth of xenograft tumor in the interference group was significantly decreased as compared with those in the negative control and the blank control groups （both P 〈 0.05）. The inhibitory rate of tumor weight in the interference group was 50.0%, The morphological features of xenograft tumors in three groups were consistent with the characteristics of squamous cell carcinoma. The expression level of VCAM-1 protein and MVD value in the interference group were decreased as compared with those in the negative control and blank control groups （all P 〈 0.01）. The VCAM-1 protein expression was positively correlated with MVD （r = 0.834, P 〈 0.05）.Conclusion： The lentivirus-mediated VCAM-1-shRNA interference can inhibit the growth and angiogenesis of xneograft tumors of human tongue squamous cell carcinoma in nude mice by silencing VCAM-1 gene expression. It is suggested that VCAM-1 may be a potential target of gene therapy for oral squamous cell carcinoma.