Effect of different doses of recombinant human bone morphogenetic protein 2 on osteogenic activities of human osteosarcoma cell line SaOS-2

Objective To investigate the effect of recombinant human bone morphogenetic protein 2 (rhBMP-2) on the osteogenic activities of human osteosarcoma cell line SaOS-2. Methods SaOS-2 cells were exposed to rhBMP-2 for 12,24,48 h at 0(control) ,2,20,200 μg/L, respectively. The mRNA expression of alkaline phosphatase(ALP) and bone gla(BCP) were detected by real time polymerase chain reaction. Results The mRNA expression of ALP and BGP of SaOS-2 cells increased gradually with rhBMP-2. The mRNA expression of ALP of the 20 μg/L group exposed for 48 h(1.60 ± 0.64), and the 200 μg/L group exposed for 12,48 h(1.70 ± 0.41, 1.80±0.19) were significantly higher than those of control (12 h: 0.80±0.25, 48 h: 0.74±0.21, allP<0.05). The mRNA expression of BGP of the 2 μg/L group exposed for 24 h(1.67 ± 0.33), the 20 μg/L group exposed for 12,24 h(2.42 ± 0.13,1.82 ± 0.14) and the 200 μg/L group exposed for 12,24 h(1.46 ± 0.11,1.24 ± 0.07) were significantly higher than those of control( 12 h: 1.01 ± 0.14, 24 h: 0.84 ± 0.12, all P< 0.05). Conclusions rhBMP-2 can promote the mRNA expression of ALP and BGP of SaOS-2 cells. They have a dose-response relationship, but represent a different dose-response effect. Key words: Bone morphogenetic proteins;  Osteogenesis;  Alkaline phosphatase;  Osteocalcin