CFU-F assay and expression of stemness markers. MSCs were plated at a density of 500 cells/plate and incubated for 14 days for the CFU-F assay. (A) The number of colonies (diameter≥2 mm) was counted. The expression levels of Oct4(B), Nanog(C), and Cxcr4(D) in control and AZA-treated MSCs were assessed by real time PCR analysis (N=4).