Figure 2. CD133/CD44, Lgr5, and CK20 expression of adherent, spheres, and differentiated HCT-116 and HT29.

CD133 (known as cancer stem cell marker) expression rises from ≤1.2% up to 60%–80% when cultured in SFM, but reduced to 5%–10% when the colonsphere changed back into adherent cells. The same change of Lgr5 (known as crypt stem cell marker) expression can be found while CK20 expression, the marker of differentiated epithelial cell, showed the adverse change.