Cloning and monoclonal antibody preparation of VEGF receptor KDR extracellular V-VIi domain and KDR expression in carcinomas of different origins
Song, S.; Zeng, L.; Wu, J.
Zhonghua Zhong Liu Za Zhi 21(2): 96-98
1999
ISSN/ISBN: 0253-3766 PMID: 11776867 Document Number: 504997
To examine the expression of VEGF receptor KDR in carcinomas of different origins and provide possibility of exploring its relation to tumor growth and metastasis. VEGF receptor KDR cDNA (V-VII) fragment was cloned from human umbilical vein with RT-PCR and expressed in E. coli Jm109. The purified GST-KDR fusion protein was used to immunize Balb/c mice and monoclonal antibody against KDR was prepared. With this monoclonal antibody, tumor tissue and related normal tissue of different origins were examined immunohistochemically for KDR expression. The frequency and intensity of KDR expression in different tumor tissues were obviously different. Transitional-cell cancer of urinary bladder was 100% KDR positive and with highest intensity, while KDR expression in breast and intestinal adenocarcinoma was weaker and that in squamous-cell carcinoma of the lung was weakest. Moreover, KDR was also weakly expressed in other cells, such as smooth muscle cells and interstitial cells. VEGF receptor is expressed not only in the endothelial cells of tumor vasculature, but also in tumor cells. Tumor cell expression of KDR varies in intensity with tumors of different origins. The possible significance of VEGF receptor expression with regard to tumor cell proliferation and metastasis is discussed.