Endosialin, an antigen recognized by monoclonal antibody FB5, is expressed as a 165-kD cell surface
glycoprotein on tumor blood vessel endothelium in several cancers, but is not detectable in normal tissue.Sequence analysis predicted that the 757-amino acid type I membrane
protein contains a signal peptide; 5 globular extracellular domains, including a C-type lectin (see OMIM 605306) domain,
a Sushi/SCR/CCP (see 300187) domain, and 3 EGF (131530) repeats; a mucin (see 158340)-like region; a
transmembrane segment; and a short cytoplasmic tail.
General function
angiogeneis
Comment
Human tumor endothelial marker 1/endosialin (TEM1/ endosialin) was recently
identified as a novel tumor endothelial cell surface marker potentially
involved in angiogenesis, although no specific function for this novel gene
has been assigned so far.
Cellular localization
Plasma membrane
Comment
Ovarian function
Luteinization
Comment
Expression regulated by
Comment
Ovarian localization
Comment
Follicle stages
Corpus luteum
Comment
By serial analysis of gene expression (SAGE), St Croix et al. (2000) identified transcripts of pan endothelial
markers (PEMs) and tumor endothelial markers (TEMs), including TEM1. RT-PCR and in situ hybridization
analyses demonstrated that TEM1 expression was restricted to neoplastic endothelial tissue and to metastatic
lesions. The authors identified TEM1 in other angiogenic tissues, namely corpus luteum and the granulation tissue
of healing wounds, supporting the concept that in many cases tumors represent unhealed wounds.