Abstract： Objective To investigate the gene expressions of TAZ and Wnt/β-catenin on the postosteogenic cells of mesenchymal stem cells (MSC) in multiple myeloma (MM) patients and to explore the potential therapeutic target of multiple myeloma bone disease (MBD).Methods Bone marrow mononuclear cells MNC from MM and controls were isolated,cultured,expanded and then induced to osteogenic differentiation.Realtime quantitative RT-PCR was employed to detect the osteogenic markers (TAZ,Wnt/β-catenin,OPN,OC,ALP and Cbf α1); and alizarin red staining for mineral deposition.The mRNA expressions of TAZ and Wnt/β-catenin in the two groups were analysed.Results Alizarin red staining was positive and the red calcium nodules were appeared on the post-osteogenic cells of MSC.The mRNA expressions of OC,ALP and Cbf α1 were 2.0958±0.5665,2.6670±0.3847,0.8463±0.3473,respectively,on the post-osteogenic cells of MSC in the experimental groups,which were significantly higher than those of pre-osteogenic cells (1.3487±0.9291,1.1452±0.6054,0.4439±0.2945) (t =2.171,6.709,2.795; all P ＜ 0.05).The mRNA expressions of OPN,OC,ALP and Cbf α1 were 2.1096±0.8267,2.8991±0.3531,4.3045±0.2844,1.3273±0.4075,respectively,on the post-osteogenic cells of MSC in the controls,which were significantly higher than those of pre-osteogenic cells (1.2200±0.9091,0.8780±0.3927,1.9161±0.2684,0.6736±0.2513) (t =2.289,12.103,25.134,4.411; all P ＜ 0.05).The mRNA expressions of OPN,OC,ALP,Cbf α1 were 1.2710±0.5636,2.0958±0.5665,2.6670± 0.3847,0.8463+0.3473,respectively,on the post-osteogenic cells of MSC in the experimental groups,which were significantly lower than those of control groups (2.1096 ±0.8267,2.8991 ±0.3531,4.3045±0.2844,1.3273±0.4075) (t =-2.650,-3.805,-10.822,-2.841; all P ＜ 0.05).The mRNA expression of TAZ and β-catenin were 2.2315±1.0723 and 0.5801±0.2159 on the post-osteogenic cells of MSC in MM patients,which were significantly lower than those of control groups (4.4140±0.8325,0.9516±0.2920) (t =±5.085,-3.235;both P ＜ 0.05).Conclusion The gene expressions of OPN,OC,ALP and Cbf α1,the osteogenesis related genes,are increased in post-osteogenic cells of MSC,which showed the MSC have been successfully induced to osteoblasts.Comparing with control groups,the osteogenic potential of MSC in MM patients is lower.Based on the above research,TAZ and Wnt/β-catenin may present a novel target for the future therapy of MBD.