Figure 5

CD44 ^bright cells show stem-like properties. The CD44^bright and CD44^dim cells were sorted by FACS from the OVCAR-3 and ES-2 cells before additional Western blotting, sphere and colony formation assays. (A) The CD44^bright cells expressed higher levels of Sox2 and Oct3/4 than the CD44^dim cells in both cell lines. (B) Larger spheres from the CD44^bright cells and cell clusters not qualified as spheres from the CD44^dim cells in both cell lines are shown (left panel) with a corresponding histogram (right panel). (C) Colony formation assay also shows more colonies in the CD44^bright cells compared to the CD44^dim cells in both cell lines (left panel). Three independent colony formation assays show statistically significantly more colonies in the CD44^bright cells, in comparison to the CD44^dim cells in both cell lines (P < 0.0001, right panel).