Mesenchymal-epithelial transitions

✍ Scribed by Walter Birchmeier; Carmen Birchmeier

• Publisher: John Wiley and Sons
• Year: 1994
• Tongue: English
• Weight: 507 KB
• Volume: 16
• Category: Article
• ISSN: 0265-9247
• DOI: 10.1002/bies.950160503

✦ Synopsis

Epithelia and mesenchyme are two distict types of tissues found in virtually every organ: epithelia are composed of closely associated, largely immobile cells, whereas mesenchyme, in contrast, contains more mobile, fibroblast-like cells that form losely associated cell agglomerations. During normal development, transitions between epithelia and mesenchyme occur (e.g. in gastrulation), and mesenchyme can differentiate into new epithelia (e.g. in kidney development). Such transitions are not confined to development. In particular, the loss of epithelial character in malignant carcinomas, resulting in the appearance of invasive, motile cells, is of major importance in tumor progression('x2). In the past decades, the biology of epithelial-mesenchymal and mesenchymal-epithelial transitions has been well characterized. However, these studies have remained essentially descriptive and it is only recently that the control events at the molecular level have become amenable to experimental studies. A recent report from George Vande Woude's laboratory(3) has given new momentum to this field: NIH3T3 fibroblasts cotransfected with the c-met receptor tyrosine kinase (expressed predominantly in epithelia) and with its ligand scatter factorhepatocyte growth factor (SF/HGF), can form tumors with epithelial (carcinoma-like) characteristics.