Figure 4
SOX2 controls the stemness properties of primary HNSCC stem-like cells. (A) Quantitative PCR analysis showing that the ALDHhigh population in HNSCC stem-like cells exhibits a relatively high expression level of SOX2 mRNA compared with ALDHlow cells. These HNSCC stem-like cells were cultured in serum-free media with EGF and bFGF. (B) Western blot analysis of protein levels of OCT4 and NANOG in HNSCC stem-like cells transfected with scrambled shRNA and in HNSCC stem-like cells transfected with shSOX2. (C) Representative photos showing the morphology of spheres in HNSCC stem-like cells transfected with scrambled shRNA and in HNSCC stem-like cells transfected with shSOX2 (left). The number of neurospheres (>10 μm) generated from HNSCC stem-like cells transfected with scrambled shRNA and from HNSCC stem-like cells transfected with shSOX2 for 14 days (right). Cells were seeded in a 24-well plate at a density of 200 cells per well and cultured in serum-free media with EGF and bFGF commitment every second day. (D) Flow cytometric analysis showing a decrease in the CD44-positive population in HNSCC stem-like cells transfected with scrambled shRNA and in HNSCC stem-like cells transfected with shSOX2. IgG was used as a negative control.
