ABSTRACT
OBJECTIVE: To explore a new method for the therapy of avascular necrosis of the femoral head. METHOD: The recombinant plasmid pCD-rbFGF was mixed with collagen and was implanted in the necrotic femoral head. Expression of basic fibroblast growth factor (bFGF) was examined by RT-PCR and immunohistochemical method. Repair of the femoral head was observed by histological and histomorphometric analysis. RESULT: Expression of bFGF was detected in the femoral head transfected with bFGF gene, indicating significant increase of angiogenesis 2 weeks after gene transfection and increased new bone formation 8 weeks after gene transfection on histomorphometric analysis (P< 0.01). CONCLUSION: Transfection of bFGF gene enhances bone tissue angiogenesis. Repair in osteonecrosis would be accelerated accordingly.
Subject(s)
Femur Head Necrosis/therapy , Femur Head/metabolism , Fibroblast Growth Factor 2/genetics , Genetic Therapy , Transfection , Animals , Collagen/therapeutic use , Fibroblast Growth Factor 2/biosynthesis , Gene Expression , Neovascularization, Physiologic , Osteogenesis , Plasmids , Rabbits , Recombinant Proteins/biosynthesis , Recombinant Proteins/geneticsABSTRACT
OBJECTIVE: To evaluate the effects of transforming growth factor beta1 (TGFbeta1) autocrine blockage on proliferation activity and drug sensitivity of osteosarcoma. METHODS; Northern blot, MTT determination, and 3H thymidine incorporation were used to investigate the effects of antisense TGF beta1 gene on osteosarcoma. RESULTS: The proliferation of osteosarcoma cells transfected by antisense TGF beta1 gene was suppressed markedly, and adriamycin sensitivity was significantly increased. CONCLUSION: Blockage of osteosarcoma cells TGF beta1 autocrine loop inhibits cell proliferation and enhances chemotherapy sensitivity.
Subject(s)
Autocrine Communication/drug effects , Bone Neoplasms/pathology , Osteosarcoma/pathology , Transforming Growth Factor beta/genetics , Antineoplastic Agents/pharmacology , Antisense Elements (Genetics)/biosynthesis , Antisense Elements (Genetics)/genetics , Bone Neoplasms/metabolism , Cell Division/drug effects , Cell Line, Tumor , Doxorubicin/pharmacology , Humans , Osteosarcoma/metabolism , RNA, Messenger/genetics , Transfection , Transforming Growth Factor beta/biosynthesis , Transforming Growth Factor beta1ABSTRACT
OBJECTIVE: To elucidate the effects of exogenous basic fibroblast growth factor (bFGF) on biological characteristics of rat osteoblasts cultured in vitro. METHODS: The osteoblasts isolated from a Sprague-Dawley rat and cultured in vitro were treated with different concentrations of bFGF (5-50 ng/ml) respectively. At 24 hours after treatment, the proliferating cell nuclear antigen was measured with immunocytochemistry, alkaline phosphatase (ALP) activity was determined and the expression of transforming growth factor beta 1 (TGF-beta(1)) was detected to observe the effects of bFGF on growth and differentiation of osteoblasts. RESULTS: bFGF (5-50 ng/ml) could obviously promote the growth of osteoblasts. The intracellular expression of TGF-beta(1) mRNA increased significantly, but the intracellular ALP content decreased. CONCLUSIONS: bFGF can obviously stimulate the proliferation of osteoblasts and promote the synthesis of TGF-beta(1), but cannot promote the differentiation of osteoblasts.
Subject(s)
Fibroblast Growth Factor 2/pharmacology , Osteoblasts/drug effects , Alkaline Phosphatase/metabolism , Animals , Cells, Cultured , Osteoblasts/metabolism , Proliferating Cell Nuclear Antigen/analysis , RNA, Messenger/analysis , Rats , Rats, Sprague-Dawley , Transforming Growth Factor beta/genetics , Transforming Growth Factor beta1ABSTRACT
OBJECTIVE: To investigate the effect of transforming growth factor-beta 1 (TGF-beta 1) gene transfer on the biological characteristics of osteoblasts. METHODS: The expression of TGF-beta 1 in the transfected osteoblasts was detected by in situ hybridization and assay of TGF-beta 1 activity in the supernatant (mink lung epithelium cell growth-inhibition test). The effects of gene transfer and supernatant of the transfected osteoblasts on the proliferation and alkaline phosphatase(ALP) activity of osteoblasts were detected by 3H-TdR and MTT. RESULTS: The results of in situ hybridization analysis suggested that the osteoblasts transfected by TGF-beta 1 gene could express TGF-beta 1 obviously. The complex medium, which was the mixture of serum-free DMEM and the activated supernatant according to 1:1, 1:2, 1:4, could inhibit growth of Mv-1-Lu evidently and the ratios of inhibition were 16.3%, 22.7%, 28.2% respectively. TGF-beta 1 gene transfer had no effect on the biological characteristics of osteoblasts, but the activated supernatant of transfected osteoblasts stimulated proliferation and inhibited ALP activity of osteoblasts. CONCLUSION: TGF-beta 1 gene transfer promotes the expression of TGF-beta 1 and the biological characteristics of transfected osteoblasts are stable, which is helpful for gene therapy of bone defects in vivo.
