靶向IGF1R基因的shRNA对人肺腺癌细胞裸鼠移植瘤生长的抑制作用

Inhibitory effect of shRNA targeting IGF1R gene on the growth of human lung adenocarcinoma in xenografts nude mice

目的探讨靶向沉默肺腺癌A549细胞IGF1R基因表达对裸鼠移植瘤生长抑制作用及其机制。方法利用IGF1RshRNA重组慢病毒、IGF1R重组慢病毒分别感染的A549细胞及未处理的A549细胞,分别构建裸鼠移植瘤模型,并命名为:实验组、阴性对照组、空白对照组。监测各组肿瘤生长情况;HE染色法观察各组移植瘤组织形态学变化,免疫组化法检测微血管密度;Western blot法检测移植瘤组织IGF1R蛋白表达水平,荧光实时定量PCR法检测HIF-1α和VEGF基因表达水平。结果实验组体积抑瘤率达(50.14±2.58)%,质量抑瘤率(55.53±3.11)%,肿瘤生长显著抑制;IGF1R蛋白相对表达水平较阴性对照组下降70.66%(P<0.05);实验组HIF-1αmRNA和VEGF mRNA相对表达量(0.34±0.02、0.46±0.04)较空白对照组(0.72±0.03、1.08±0.06)及阴性对照组(0.68±0.04、1.00±0.07)显著降低(P<0.05);与空白对照组、阴性对照组比较,实验组肿瘤细胞稀疏,MVD明显下降。结论慢病毒载体介导的IGF1R shNRA能有效抑制肺腺癌细胞裸鼠移植瘤的生长。

Objective To explore the inhibitory effect of targeting IGF1R gene expression in lung carcinoma A549 cells on tumor growth in nude mice and its mechanism. Methods IGF1R-shRNA recombinant lentivirus, IGF1R recombinant lentivirus infections were used to infect the A549 cells respectively. Eighteen nude mice were randomized into negative control group, experiment group and blank control group. The infected A549 cells and A549 cells were incubated into nude mice to induce the xenografts model ,respecively. The tumor growth was monitored. HE staining was used to observe the morphologie changes of transplanted tumor, the immunohistochemistry was used to detect the microvessel ctensity, Western blot was applied to detect IGF1R protein expression levels in transplanted tumor, and real-time quantitative fluorescent PCR method was used to detect HIF-1α and VEGF gene expression levels in xenografts. Results The inhibitory rate was （50.14 ± 2.58 ） % for tumor size and （ 55.53 ± 3.11 ） % for tumor weight in experiment group. The tumor growth was significantly suppressed in experiment group. IGF1R protein expression levels decreased by 70.66% in experiment group（ P 〈 0.05 ）. The HIF-1α mRNA and VEGF mRNA expression was significantly lower in experiment group than that in two con- trol groups （ P 〈 0. 05 ）, Compared with two control groups, tumor cells were sparse in experiment group, and MVD decreased markedly. Conclusion IGF1R shRNA mediated by lentiviral vector can effectively inhibit the growth of human lung adenocarcinoma xenografts in nude mouse.