Journal Article

Multiparameter Analysis, including EMT Markers, on Negatively Enriched Blood Samples from Patients with Squamous Cell Carcinoma of the Head and Neck

Old, Mathew, Schuller, David E., Lustberg, Maryam B., Ozer, Enver, Teknos, Theodoros N., Zborowski, Maciej, Lang, James C., Balasubramanian, Priya, Summers, Thomas A., Agrawal, Amit, Miller, Brandon, Chalmers, Jeffrey J., Jatana, Kris R.

2012

Overview

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.

• Publisher: Public Library of Science,Public Library of Science (PLoS)
• Subject: Adult / Aged / Analysis / Antigens, Neoplasm - metabolism / Biology / Biomarkers, Tumor - metabolism / Blood / Breast cancer / Cadherin / Cadherins / Cancer / Cancer metastasis / Carcinogenesis / Carcinogens / Carcinoma, Squamous Cell - blood / Carcinoma, Squamous Cell - metabolism / Carcinoma, Squamous Cell - pathology / CD44 antigen / Cell Adhesion Molecules - metabolism / Cell Line, Tumor / Cell surface / Chemistry / Confocal microscopy / Engineering / Enrichment / Epidermal growth factor / Epidermal growth factor receptors / Epithelial Cell Adhesion Molecule / Epithelial-Mesenchymal Transition / Female / Genotype & phenotype / Head & neck cancer / Head and neck cancer / Head and Neck Neoplasms - blood / Head and Neck Neoplasms - metabolism / Head and Neck Neoplasms - pathology / Humans / Leukocyte Common Antigens - metabolism / Lymphatic system / Male / Markers / Medical prognosis / Medicine / Mesenchyme / Metastases / Metastasis / Microscopy / Middle Aged / N-Cadherin / Neck / Neoplastic Cells, Circulating - pathology / Nuclei / Nuclei (cytology) / Otolaryngology / Patients / Positive selection / Proteins / Squamous cell carcinoma / Stem cells / Surface markers / Surgery / Technology / Tumor cells / Tumors / Vimentin