BACKGROUND: Bone marrow mesenchymal stem cells (BMMSCs) can be induced differentiating into osteoblasts and chondroblasts, DNA methylate depressant 5-azacytidine can induce BMMSCs expressing myogenic regulating factors: Myf5 and myopoietin, which involving in the differentiation of BMMSCs into myoblasts.OBJECTIVE: Muscular traumatic fluid containing the highest protein content was screened out and co-cultured with BMMSCs,in order to explore the inductive effect on the proliferation and myogeneis of BMMSCs.DESIGN : Standardized comparative study.SETTING .:At State Key Laboratory of Trauma, Bums and Combined Injury,Institute of Combined Injury, Medical College of Preventive Medicine, Third Military Medical University of Chinese PLA.MATERIALS: Muscular traumatic model was established on 18 Balb/C pure rats for the extraction of muscular traumatic fluid, the inductive effect of the fluid on BMMSC was then compared with 5-azacytidine.METHODS:This study was carried out at State Key Laboratory of Trauma,Burns and Combined Injury, Institute of Combined Injury, College of Preventive Medicine, Third Military Medical University of Chinese PLA from April 2001 and September 2003. Bradford colorimetric was used to detect the protein content in the muscular traumatic fluid, and the fluid with the highest protein was used to co-culture with BMMSC, whose effect on the proliferation of BMMSC was measured with MTT methods at day 0, 3, 6, 9, 12, 15.RT-PCR technique was used to detect the expression of myopoietin at day 6,with its myogenic effect compared with that of 5-azacytidine.fluid on BMMSC.eration of BMMSC: the proloferative activity of BMMSC in traumatic fluid genic effect of traumatic fluid on BMMSC: myopoietin could not be found expressed in traumatic fluid group, but strongly expressed in 5-azacytidine group.CONCLUSION: Muscular traumatic fluid can promote the proliferation of BMMSC, but has no myogenic effect.

Objective: To investigate the effect of CK2 (casein kinase 2) inhibitor CX4945 on the cisplatin (DDP)-resistance of lung cancer A549/DDP cells and the underlying molecular mechanism. Methods: The CCK-8 assay was used to detect the half maximal inhibitory concentration (IC50) of DDP in lung cancer A549 and A549/DDP cells, and to compare the DDP-resistance of two cell lines. The effect of CX4945 on DDP-resistance of A549/DDP cells was tested by CCK-8 method. Western blotting was used to detect the expressions of Wnt signaling pathway-related proteins (CK2α, β-catenin and cyclin D1), drug resistance-related proteins [multidrug resistance-associated protein 1 (MRP1) and lung resistance-related protein (LRP)] and apoptosis-related protein [cleaved caspase-3 (c-caspase-3)] in A549 and A549/DDP cells treated with DDP or not. The A549/DDP cells were treated with no drug (as the control group), CX4945, DDP and their combination (as CX4945+DDP group), then the expressions of Wnt signaling pathway-, drug resistance- and apoptosis-related proteins were detected by Western blotting, and the apoptosis of A549/DDP cells was detected by FCM method. Results: The IC50 value of DDP in A549/DDP cells was 4.59 times higher than that in A549 cells, and the DDP-resistance of A549/DDP cells was decreased by CX4945 pretreatment (P < 0.001). The expression levels of CK2α, β-catenin, cyclin D1, MRP1 and LRP proteins were significantly increased in A549/DDP cells as compared with A549 cells (all P < 0.001), and the levels of these proteins in A549/DDP cells were further increased after DDP treatment (all P < 0.001). In A549 cells after treatment with DDP, the expression levels of CK2α, β-catenin and cyclin D1 proteins were reduced (all P < 0.01), but the levels of MRP1 and LRP proteins were not significantly changed (both P > 0.05). Compared with the control group and DDP group, the expression levels of β-catenin, cyclin D1, MRP1 and LRP proteins in A549/DDP cells of CX4945 group and CX4945+DDP group were significantly declined (all P < 0.01). In addition, the apoptosis rate of A549/DDP cells and the expression level of c-caspase-3 in CX4945+DDP group were significantly higher than those in the control group and DDP group (all P < 0.001). Conclusion: CK2 inhibitor CX4945 can reverse the DDP resistance of lung cancer A549/ DDP cells through blocking Wnt signal pathway and decreasing the expressions of drug resistance-relatied proteins.

Objective To identify the effect of both high glucose and high insulin on miR-145 level.Methods The human vascular smooth muscle cells ( VSMCs) were cultured and the proliferation of VSMCs was induced by high glucose and high insulin medium.The samples were divided into 4 groups: normal group, high glu-cose group (25 mmol/L), high insulin group (300 mU/L), high glucose and high insulin group.The ex-pression of miR-145 in VSMCs was assayed by real-time PCR.Proliferation of VSMCs was determined by MTT method After 72 h cultivation.The migration of VSMCs was analyzed by cell scratch test .VSMCs in each group was transfected by miR-145 virus ( lentiviral vector ) .Proliferation and migration were assayed after 48 h transfection.Results The expression of miR-145 in VSMCs of other three groups was decreased ( P<0.05 ) , especially the expression in the high glucose and insulin group was the lowest ( P<0.01 ) .Prolifera-tion and migration of VSMCs was promoted by high glucose and/or high insulin medium.Under fluorescent, transfection rate of VSMCs was about 80%after 48 h transfection.Proliferation and migration of VSMCs in each group after transfection were significantly lower than before ( P<0.05 ) .Conclusions High glucose and high in-sulin could decrease the expression of miR-145 in VSMCs, The overexpression of miR-145 may inhibit the prolif-eration and migration of VSMCs .