title: Multiparameter analysis, including EMT markers, on negatively enriched blood samples from patients with squamous cell carcinoma of the head and neck.
abstract: Epithelial to mesenchymal transition (EMT) has been hypothesized as a mechanism by which cells change phenotype during carcinogenesis, as well as tumor metastasis. Whether EMT is involved in cancer metastasis has a specific, practical impact on the field of circulating tumor cells (CTCs). Since the generally accepted definition of a CTC includes the expression of epithelial surface markers, such as EpCAM, if a cancer cell loses its epithelial surface markers (which is suggested in EMT), it will not be separated and/or identified as a CTC. We have developed, and previously reported on the use of, a purely negative enrichment technology enriching for CTCs in the blood of squamous cell carcinoma of the head and neck (SCCHN). This methodology does not depend on the expression of surface epithelial markers. Using this technology, our initial data on SCCHN patient blood indicates that the presence of CTCs correlates with worse disease-free survival. Since our enrichment is not dependent on epithelial markers, we have initiated investigation of the presence of mesenchymal markers in these CTC cells to include analysis of: vimentin, epidermal growth factor receptor, N-cadherin, and CD44. With the aid of confocal microscopy, we have demonstrated not only presumed CTCs that express and/or contain: a nucleus, cytokeratins, vimentin, and either EGFR, CD44, or N-cadherin, but also cells that contain all of the aforementioned proteins except cytokeratins, suggesting that the cells have undergone the EMT process. We suggest that our negative depletion enrichment methodology provides a more objective approach in identifying and evaluating CTCs, as opposed to positive selection approaches, as it is not subjective to a selection bias and can be tailored to accommodate a variety of cytoplasmic and surface markers which can be evaluated to identify a multitude of phenotypic patterns within CTCs from individual patients, including so-called EMT as presented here.
authors: William G. Lowrie Department of Chemical and Biomolecular Engineering, The Ohio State University, Columbus, Ohio, United States of America.
authors: Priya
authors: P
authors: Balasubramanian
authors: James C
authors: JC
authors: Lang
authors: Kris R
authors: KR
authors: Jatana
authors: Brandon
authors: B
authors: Miller
authors: Enver
authors: E
authors: Ozer
authors: Mathew
authors: M
authors: Old
authors: David E
authors: DE
authors: Schuller
authors: Amit
authors: A
authors: Agrawal
authors: Theodoros N
authors: TN
authors: Teknos
authors: Thomas A
authors: TA
authors: Summers
authors: Maryam B
authors: MB
authors: Lustberg
authors: Maciej
authors: M
authors: Zborowski
authors: Jeffrey J
authors: JJ
authors: Chalmers
mesh_terms: D000328:Adult; D000368:Aged; D000951:Antigens, Neoplasm / Q000378:metabolism; D014408:Biomarkers, Tumor / Q000378:metabolism*; D002294:Carcinoma, Squamous Cell / Q000097:blood* / Q000378:metabolism / Q000473:pathology*; D015815:Cell Adhesion Molecules / Q000378:metabolism; D045744:Cell Line, Tumor; D000071858:Epithelial Cell Adhesion Molecule; D058750:Epithelial-Mesenchymal Transition; D005260:Female; D006258:Head and Neck Neoplasms / Q000097:blood* / Q000378:metabolism / Q000473:pathology*; D006801:Humans; D017493:Leukocyte Common Antigens / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D009360:Neoplastic Cells, Circulating / Q000473:pathology*
chemical_list: D000951:Antigens, Neoplasm; D014408:Biomarkers, Tumor; D015815:Cell Adhesion Molecules; D000071858:Epithelial Cell Adhesion Molecule; D017493:Leukocyte Common Antigens