ABSTRACT
Objective To study the effect of TLR4 activation with LPS on BMP9-induced osteogenic differentiation of immortalized mouse embryonic fibroblasts ( iMEFs).Methods The activation of TLR4/NF-κB signaling path-way was detected by ICC.iMEFs were treated with LPS,BAY11-7082,Adnovirus GFP and BMP9.The early osteo-genic differentiation capability of iMEFs was detected by ALP staining and quantitative assay .The later osteogenic differentiation capability was detected by alizarin red S staining .The expression of later osteogenic differentiation marker gene OCN and OPN were detected by PCR and Western blot .The change of p-Smad1/5/8 was detected by Western blot.The expression of Runx2 and Dlx5 were detected by PCR and Western blot .Results LPS can effec-tively stimulate TLR4/NF-κB signaling pathway .TLR4 activation inhibited BMP 9-induced osteogenic differentiation . BMP9-induced osteogenic differentiation related gene and Smad 1/5/8 signaling activation were inhibited by TLR4 activation .The inhibition effect was partly reversed by BAY 11-7082 ( P<0.05 ) .Conclusions TLR4 activation with LPS can inhibit BMP9-induced osteogenic differentiation of iMEFs cells via NF-κB signaling pathway .
ABSTRACT
AIM:To investigate the effect of bone morphogenetic proteins 9 (BMP9) on the migration and in-vasion abilities of human lung squamous-cell carcinoma NCI-H520 cells and its mechanism.METHODS:The expression of BMP9 at mRNA and protein levels in the NCI-H520 cells and human bronchial epithelial ( HBE) cells was detected by RT-PCR and Western blot.The NCI-H520 cells were transfected with the recombinant adenovirus AdBMP9 and the expres-sion of BMP9 at mRNA and protein levels was validated by RT-PCR and Western blot.The migration and invasion abilities of the NCI-H520 cells were determined by wound-healing and Transwell assays.The mRNA and protein levels of the migra-tion-related factor matrix metalloproteinase 2 (MMP2) were detected by RT-PCR and Western blot.The level of phospho-rylated Smad1/5 (p-Smad1/5) was detected by Western blot.Meanwhile, NCI-H520 cells were treated with BMP specific antagonist AdNoggin and AdBMP9.The level of p-Smad1/5 and the cell migration ability were measured by Western blot, wound-healing and Transwell assays.RESULTS:The expression of BMP9 at mRNA and protein levels was lower in NCI-H520 cells than that in HBE cells.After AdBMP9 was stably transfected into the NCI-H520 cells, the expression of BMP9 at mRNA and protein levels was significantly up-regulated, cell migration and invasion abilities were significantly de-creased, and the mRNA and protein levels of MMP2 were decreased.Meanwhile, the level of p-Smad1/5 was increased. Noggin reversed BMP9-caused the increase in p-Smad1/5 and the decrease in cell migration ability.CONCLUSION:O-ver-expression of BMP9 inhibits the migration and invasion abilities of lung squamous-cell carcinoma NCI-H520 cells.The activation of BMP-Smad signaling pathway may be involved in this inhibitory process.