The tumour-associated antigen EpCAM upregulates the fatty acid binding protein E-FABP.
The epithelial cell adhesion molecule, EpCAM, is a transmembrane glycoprotein associated with both benign and malignant proliferation. In cancer cells, expression levels of this tumour-associated antigen correlate positively with the grade of dysplasia and are also a negative prognostic factor for breast cancer patients. De novo expression of EpCAM resulted in the rapid upregulation of the proto-oncogene c-Myc along with enhanced cell proliferation and metabolism. Here, we analyzed the effects of EpCAM onto the proteome of epithelial cells. The epidermal fatty acid binding protein, E-FABP, was identified as a new EpCAM-regulated protein. E-FABP is a major target of c-Myc and was rapidly upregulated upon induction of EpCAM. Additionally, E-FABP levels correlated with the amount of EpCAM in permanent squamous cell carcinoma lines and in vivo in primary head and neck carcinomas. Taken together, these results provide further evidence for the direct involvement of EpCAM in signalling processes, gene regulation, and cellular metabolism supporting its important role in tumour biology.
Münz
Markus
M
Head and Neck Research Department, Clinical Cooperation Group Molecular Oncology, GSF, National Research Center for Environment and Health, Marchioninistr. 15, 81377 Munich, Germany. markus.muenz@med.uni-muenchen.de
Zeidler
Reinhard
R
Gires
Olivier
O
D000943:Antigens, Differentiation; D000951:Antigens, Neoplasm / Q000502:physiology*; D002294:Carcinoma, Squamous Cell / Q000235:genetics*; D002352:Carrier Proteins; D015815:Cell Adhesion Molecules / Q000502:physiology*; D049109:Cell Proliferation; D000071858:Epithelial Cell Adhesion Molecule; D004847:Epithelial Cells; D050556:Fatty Acid-Binding Proteins; D005227:Fatty Acids; D015972:Gene Expression Regulation, Neoplastic; D016259:Genes, myc; D006801:Humans; D020543:Proteome; D000090063:Proto-Oncogene Mas; D015398:Signal Transduction; D014407:Tumor Cells, Cultured; D015854:Up-Regulation
D000943:Antigens, Differentiation; D000951:Antigens, Neoplasm; D002352:Carrier Proteins; D015815:Cell Adhesion Molecules; C499379:EPCAM protein, human; D000071858:Epithelial Cell Adhesion Molecule; C493412:FABP5 protein, human; D050556:Fatty Acid-Binding Proteins; D005227:Fatty Acids; C000715470:MAS1 protein, human; D020543:Proteome; D000090063:Proto-Oncogene Mas