ISOLATION AND CHARACTERIZATION OF CANCER STEM CELL SUBPOPULATIONS IN ORAL SQUAMOUS CELL CARCINOMA

Abstract

<h3>Objectives</h3> Cancer stem cells (CSCs) comprise a subpopulation of tumor cells associated with initiation, progression, and chemoresistance. We identified, isolated, and characterized subpopulations of CSC in SCC-9 ZsGreen (SCC-9 ZsG) and LN1-A cell lines derived from oral squamous cell carcinoma (OSCC). <h3>Study Design</h3> SCC-9 ZsG and LN-1A subpopulations were identified and isolated with antibodies against CD44 and CD326 by flow cytometry. Cell morphology, proliferation, migration, clonogenic assay, and protein expression associated with epithelial-mesenchymal transition were carried out. <h3>Results</h3> Six and 7 phenotypes were isolated in SCC-9 ZsG and LN-1A cells in relation to its differential expression, respectively. CD44-low/CD326+ subpopulations showed epithelial phenotype with polygonal morphology and high expression of E-cadherin, whereas CD44+/CD326− showed a fusiform morphology with a high expression of vimentin, N-cadherin, and Slug, suggesting a mesenchymal phenotype. CD44-high/CD326− subpopulations were exclusively identified and isolated in LN-1A cells, also presenting a mesenchymal phenotype. Proliferation, migration, and colony formation were increased in CD44+/CD326− compared to CD44-low/CD326+ and parental cells in SCC-9 ZsG. <h3>Conclusions</h3> Our preliminary results showed that CD44-high/CD326− cells were correlated to a more malignant phenotype. Further experiments will be needed to better characterize the populations of CSC in OSCC.