[ROLE OF FORKHEAD/FOX TRANSCRIPTION FACTOR 2 OVER-EXPRESSION IN REGULATING OSTEOGENIC DIFFERENTIATION OF BONE MARROW MESENCHYMAL STEM CELLS BY Wnt SIGNALING PATHWAYS]

To investigate the role of the forkhead/Fox transcription factor 2 (Foxc2) over-expression in regulating osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) by Wnt-β-catenin signaling pathwaysThe recombinant lentivirus carrying green fluorescent protein (group A) or Foxc2 (group B) were used to transfect the fifth generation rabbit BMSCs, and untransfected BMSCs served as a control (group C). The cell viability was measured with water soluble tetrazolium-1 (WST-1) regent at 72 hours after transfection. After 2 weeks of transfection, the expression of β-catenin in BMSCs was detected by real time fluorescence quantitative PCR, Western blot, and immunofluorescence staining. Meanwhile, the β-catenin inhibitors XAV-939 (0, 0.1, and 1.0 μmol/L) was added in group B; at 2 weeks after osteogenic and adipogenic induction, the gene and protein expressions of collagen type I (COL I), osteocalcin (OCN), and peroxisome proliferator activated receptor gamma 2 (PPARγ-2) were detected by real time PCR and Western blot.WST-1 results showed that the cell viability of group B (130.85%±0.15%) was significantly higher than that of group A (100.45%±0.35%) (The over-expression of Foxc2 gene in BMSCs may promote osteogenic differentiation by Wnt-β-catenin signaling pathway.观察过表达插头框转录因子C2（forkhead/Fox transcription factor 2，Foxc2）经Wnt-β链蛋白（β-catenin）信号通路调节兔BMSCs成骨分化，为基因转染BMSCs修复股骨头坏死提供理论依据。.利用慢病毒携带Foxc2或绿色荧光蛋白（green fluorescent protein，GFP）基因的重组慢病毒载体Lv-GFP（A组）及Lv-Foxc2（B组）转染第5代兔BMSCs，以未转染BMSCs为对照（C组）。慢病毒转染后72 h采用水溶性四氮唑-1（water soluble tetrazolium-1，WST-1）法检测细胞活性；慢病毒转染2周，通过免疫荧光染色、Western blot及实时荧光定量PCR检测过表达Foxc2对β-catenin表达水平的影响。然后，在B组中添加不同剂量（0、0.1、1.0 μmol/L）β-catenin抑制剂XAV-939，成骨、成脂诱导2周后，采用Western blot和实时荧光定量PCR检测各组成骨因子Ⅰ型胶原（collagen typeⅠ，COLⅠ）、骨钙素（osteocalcin，OCN）及成脂因子过氧化物酶体增殖体激活受体γ2（peroxisome proliferator activated receptor gamma 2，PPARγ-2）蛋白和基因的表达。.WST-1检测示，转染72 h B组细胞活性为130.85%±0.15%，显著高于A组的100.45%±0.35%，差异有统计学意义（过表达Foxc2通过调节Wnt-β-catenin信号通路促进BMSCs成骨分化。.