Raskopf E, Vogt A, Standop J, Sauerbruch T, Schmitz V
Department of Inner Medicine I, University of Bonn, Medical School, Bonn Germany.
Z Gastroenterol. 2010 Jan;48(1):21-7. doi: 10.1055/s-0028-1109907. Epub 2010 Jan 13.
Neuropilin-1 (Nrp1) was recently described as a novel receptor for the pro-angiogenic molecule vascular endothelial growth factor (VEGF), indicating a role in tumor angiogenesis and tumor progression. Recent data confirm this assumption by demonstrating that some tumor and endothelial cells express Nrp1. Therefore, we wanted to investigate the potential role of Nrp1-knockdown on hepatoma and endothelial cell function in vitro and tumor growth in vivo. Nrp1 knockdown in SVEC4 - 10 and Hepa129 cells and its influence on signal transduction (MAPK pP38, pAKT, pERK1 / 2) was analyzed by Western blot. Effects on endothelial tube formation were assayed in an in vitro and in vivo matrigel assay. In vivo, effects of siRNA-Nrp1 were analyzed in a subcutaneous hepatoma model. To verify effects on endothelial and tumor cells in vivo, immunohistochemistry for proliferation, apoptosis and endothelial vessels was performed. LightCycler and Western blot analysis showed efficient inhibition of gene expression in SVEC4 - 10 and Hepa129 cells following siRNA-Nrp1 transfection. Signal transduction pathways were not influenced after siRNA-Nrp1 treatment compared to the controls. Endothelial tube formation was reduced by 59 % and 94 % in vitro and in vivo compared to controls, corresponding to reduced VCAM expression. Subcutaneous tumor growth was not influenced after siRNA treatment. Intratumoral proliferation was not altered after treatment with siRNA-Nrp1, whereas microvessel density and apoptosis were reduced after treatment with siRNA-Nrp1 compared to siRNA-Ctrl. In conclusion, inhibition of Nrp1 expression led to strong anti-endothelial effects, whereas tumor cells and tumor growth were not affected.
神经纤毛蛋白-1（Nrp1）最近被描述为促血管生成分子血管内皮生长因子（VEGF）的一种新型受体，表明其在肿瘤血管生成和肿瘤进展中发挥作用。最近的数据通过证明一些肿瘤细胞和内皮细胞表达Nrp1证实了这一假设。因此，我们想研究敲低Nrp1对体外肝癌细胞和内皮细胞功能以及体内肿瘤生长的潜在作用。通过蛋白质免疫印迹法分析了SVEC4 - 10细胞和Hepa129细胞中Nrp1的敲低情况及其对信号转导（MAPK pP38、pAKT、pERK1 / 2）的影响。在体外和体内基质胶试验中检测了对内皮管形成的影响。在体内，在皮下肝癌模型中分析了siRNA-Nrp1的作用。为了验证对体内内皮细胞和肿瘤细胞的影响，进行了增殖、凋亡和内皮血管的免疫组织化学检测。LightCycler和蛋白质免疫印迹分析显示，siRNA-Nrp1转染后，SVEC4 - 10细胞和Hepa129细胞中的基因表达受到有效抑制。与对照组相比，siRNA-Nrp1处理后信号转导通路未受影响。与对照组相比，体外和体内内皮管形成分别减少了59%和94%，这与VCAM表达降低相对应。siRNA处理后皮下肿瘤生长未受影响。用siRNA-Nrp1处理后肿瘤内增殖未改变，而与siRNA-Ctrl相比，用siRNA-Nrp1处理后微血管密度和凋亡减少。总之，抑制Nrp1表达导致强烈的抗内皮细胞作用，而肿瘤细胞和肿瘤生长未受影响。
