Isolation and genomic characterization of cancer stem cells in head and neck cancer

This study investigated the use of three different established cell sorting strategies to isolate and characterize stem cells from head and neck cancer cell lines. Five low passage cell lines were subjected to cell sorting based on Hoechst side population, Aldefluor and CD44 expression. Isolated cell populations were studied for gene expression, radiosensitivity and chemosensitivity to cis-platin and paclitaxel Each sorting method identified a different set of genes associated with different Gene Ontology categories with mitosis being the only common category. CD44 associated gene changes were almost exclusively associated with cell cycle and in particular mitosis. There were no significant differences in radiosensitivity or cis-platin sensitivity of stem or non-stem cells but CD44 isolated stem cells were more resistant to paclitaxel Five head and neck cell lines were used to isolate cancer stem cells by 3 isolation methods. For each isolation method, cancer stem cell enriched populations (n=5) were compared to cancer stem cell depleted populations (n=5). The resulting gene expression patterns were compared among the 3 isolation methods.