Expression of receptors tyrosine kinase c-kit and EGF-R in colorectal adenocarcinomas: is there a relationship with epithelial-mesenchymal transition during tumor progression?

C-kit is expressed in almost all GISTs, and the tumorigenesis of GISTs (which are mesenchymal tumors) involves mutations resulting in constitutive activation of tyrosine kinase receptor c-kit. It should be interesting to investigate the possible relationships between c-kit and EGF-R expression and EMT that occurs during neoplastic progression in the epithelial cancer cells in the bulk tumor, at the tumor invasion front, and in regional nodal and distant metastasis of colorectal carcinomas. The variability in EMT markers expression have been recently showed in neoplastic cells of these different topographic sites of the same tumor with occurrence of a reverting mesenchymal– epithelial transition (MET) and re-expression of epithelial phenotype in neoplastic cells during metastatic seeding .