Rivet Jacqueline, Mourah Samia, Murata Hideyuki, Mounier Nicolas, Pisonero Helena, Mongiat-Artus Pierre, Teillac Pierre, Calvo Fabien, Janin Anne, Dosquet Christine
Laboratoire de Pathologie and U728, INSERM, Université Paris 7, Hôpital Saint-Louis, AP-HP, and Institut Universitaire d'Hématologie, Paris, France.
Cancer. 2008 Jan 15;112(2):433-42. doi: 10.1002/cncr.23186.
Tumor angiogenesis is a dynamic process that plays a major role in cancer progression. Vascular endothelial growth factor (VEGF) and its receptors play a pivotal role in angiogenesis. The expression of VEGF and its receptors VEGFR-1 and VEGFR-2 in renal cell carcinoma (RCC) was investigated in the perspective of anti-VEGF treatments.
Total VEGF protein levels were quantified by enzyme-linked immunosorbent assay (ELISA) in tumor tissue samples from surgical specimens of 65 patients with clear cell RCC. At the cellular level the VEGF isoforms VEGFR-1 and VEGFR-2 mRNA were quantified by real-time quantitative reverse-transcriptase polymerase chain reaction (RT-PCR) in laser-microdissected tumoral epithelial as stromal cells and in corresponding normal tissue compartments. Colocalization of VEGF and VEGFR-1 proteins was studied by triple immunofluorescent labeling.
Protein VEGF in cytosolic extracts was significantly higher in tumoral than in nontumoral tissue (P< .0001). Event-free survival was significantly longer for patients with cytosolic VEGF lower than the cutoff (75th percentile of VEGF protein levels, P= .02). In laser-microdissected epithelial cells, VEGF(121) and VEGFR-1 mRNA expressions were higher in RCC than in corresponding nontumoral kidney (P= .007 and P= .002, respectively); they were also higher in stromal cells of RCC compared with nontumoral kidney (P= .02 and P= .003, respectively). There was no differential VEGFR-2 expression in epithelial or in stromal cells of tumoral or nontumoral kidney. By immunofluorescent labeling VEGF and VEGFR-1 colocalized on RCC tumor epithelial and stromal cells.
Combined laser microdissection and quantitative RT-PCR, as triple immunofluorescent labeling, underlined the preferential expression of the most soluble VEGF isoform, VEGF(121), and its receptor VEGFR-1, but not VEGFR-2, in epithelial and stromal cells of RCC.
肿瘤血管生成是一个动态过程,在癌症进展中起主要作用。血管内皮生长因子(VEGF)及其受体在血管生成中起关键作用。从抗VEGF治疗的角度研究了VEGF及其受体VEGFR-1和VEGFR-2在肾细胞癌(RCC)中的表达。
通过酶联免疫吸附测定(ELISA)对65例透明细胞RCC手术标本的肿瘤组织样本中的总VEGF蛋白水平进行定量。在细胞水平上,通过实时定量逆转录聚合酶链反应(RT-PCR)对激光显微切割的肿瘤上皮细胞、基质细胞及相应正常组织区域中的VEGF亚型VEGFR-1和VEGFR-2 mRNA进行定量。通过三重免疫荧光标记研究VEGF和VEGFR-1蛋白的共定位。
肿瘤组织胞质提取物中的蛋白VEGF显著高于非肿瘤组织(P<0.0001)。胞质VEGF低于临界值(VEGF蛋白水平的第75百分位数,P = 0.02)的患者无事件生存期显著更长。在激光显微切割的上皮细胞中,RCC中VEGF(121)和VEGFR-1 mRNA表达高于相应的非肿瘤性肾组织(分别为P = 0.007和P = 0.002);与非肿瘤性肾组织相比,RCC基质细胞中的表达也更高(分别为P = 0.图2和P = 0.003)。肿瘤或非肿瘤性肾的上皮或基质细胞中VEGFR-2表达无差异。通过免疫荧光标记,VEGF和VEGFR-1在RCC肿瘤上皮和基质细胞中共定位。
联合激光显微切割和定量RT-PCR以及三重免疫荧光标记,突显了最具可溶性的VEGF亚型VEGF(121)及其受体VEGFR-1而非VEGFR-2在RCC上皮和基质细胞中的优先表达。