RRC ID 1370
Author Aihara M, Sugawara K, Torii S, Hosaka M, Kurihara H, Saito N, Takeuchi T.
Title Angiogenic endothelium-specific nestin expression is enhanced by the first intron of the nestin gene.
Journal Lab Invest
Abstract Nestin is a member of intermediate filaments abundantly expressed in neural stem cells and glioblastomas. The nestin gene has four exons and three introns, and neural cell-specific expression is regulated by the second intron. We previously reported that nestin was invariably detected in the tumor endothelium in gliomas even though tumor cells were negative for nestin. In the present study, we further confirmed nestin immunostaining in tumor endothelium of a variety of common cancers, including lung, stomach, colon, and cervical carcinomas. We examined an endothelium-specific regulator using human umbilical vein endothelial cells (HUVECs) and human glioblastoma-derived U251 cells. In a luciferase reporter assay, the first intron plus 5' upstream promoter (5'UP) gave the highest activity, followed by 5'UP, and the second intron plus 5'UP. However, the assay values were much lower by HUVEC extracts than by U251 cell extracts. Although green fluorescent protein expression was positive over all U251 cells under either the first intron, second intron, or ubiquitously active CAG promoter, the fluorescence in HUVECs was limited to a few cells even under the first intron. This difference came from the growth feature of HUVECs which exhibit growth arrest by contact inhibition. We found that the nestin expression was specific to proliferative endothelium, by using proliferation markers in hemangioblastomas and in situ hybridization. Using an endothelial tube formation assay, tyrosine kinase domain-deleted VEGF receptor KDR effectively abolished the tube formation under the first intron. We suggest that the nestin expression in tumor endothelium is enhanced by the first intron.
Volume 84(12)
Pages 1581-92
Published 2004-12-1
DOI 10.1038/labinvest.3700186
PII 3700186
PMID 15502861
IF 4.197
Times Cited 49
WOS Category PATHOLOGY MEDICINE, RESEARCH & EXPERIMENTAL
Resource
DNA material AxCANCre (RDB01748)
Human and Animal Cells U251(RCB0461)