Figure 2.
Endothelial cell-secreted factors enhance the survival of HNCSC. (A,B) Graph depicting the percentage of apoptotic cells, as determined by propidium iodide staining followed by flow cytometry. ALDH+CD44+ (cancer stem-like cells) or ALDH−CD44− (control cells) sorted from the primary tumor-derived (UM-SCC-22A) or from the metastatic lymph node-derived (UM-SCC-22B) cell lines. Cells were cultured either in serum-free conditioned medium collected from primary endothelial cells (EC CM) or in serum-free endothelial basal medium (EBM) in ultra-low attachment plates for 24 hours. Asterisks depict P<0.05.
