Osteogenic differentiation of hADSCs. Compared to non-induced control (A), Alkaline phosphatase staining was increased after being induced for 2 weeks (B) (Bars = 100 μm) and ALP activity was quantified by PNPP analysis (C). *P < 0.01. Calcium nodule formation was demonstrated by Alizarin red staining (D: non-induced control; E: induced for 4 weeks) (Bars = 100 μm). (F) The expression of the osteogenic specific marker osteopontin (OPN) was detected by sqRT-PCR, lane 1: non-induced hADSCs control; lane 2: hADSCs induced for 2 weeks; lane 3: hADSCs induced for 4 weeks.