The Control of Tumor Cell Invasiveness in Chondrosarcoma Cell Lines by Modifying Focal Adhesion Kinase Expression / 대한정형외과학회잡지

PURPOSE: We propose that cell attachment and invasion can be regulated by the modulation of FAK expression in chondrosarcoma cell lines. MATERIALS AND METHODS: The C-terminal domain of FAK (FAK-CD) was transfected by recombinant adenovirus infection in chondrosarcoma cell lines, JJ012 and 105KC. The expression of FAK, FAK-CD and tyrosine phosphorylation were checked. Chondrocytes and chondrosarcoma cells were used in cell attachment tests by blocking or not blocking integrin-beta 1 antibodies and synthetic peptides on type II collagen. To evaluate the effect of cell invasiveness, a wound healing assay and a Boyden chamber assay were done after FAKCD transfection. RESULTS: We observed higher FAK expression in the chondrosarcoma cells than in chondrocytes. The level of attachment to type II collagen was significantly inhibited by blocking with the antibody of integrin-beta 1 and synthetic RGD peptides. Also, the adenovirus mediated transfection of FAK-CD resulted in the inhibition of the phosphorylation of FAK and significant inhibition of cell attachment in only JJ012, without changing FAK expression. Moreover, migration after transfection with FAK-CD was reduced by up to 79.9% for JJ012 and 75.5% for 105KC. CONCLUSION: Attachment of chondrosarcoma cells could be mediated through integrin-beta 1. We conclude that modified FAK expression contributes to the suppression of tumor cell attachment and invasion.

The control of chondroid cell's adhesiveness by modulation of focal adhesion kinase(FAK) expression / 대한정형외과연구학회지

PURPOSE: We propose that cell attachment can be regulated by the modulation of FAK expression using an adenovirus vector. MATERIALS AND METHODS: Chondrocytes and chondroid cells were used in cell attachment test by blocking or non-blocking of antibodies and synthetic peptides on type II collagen precoated 96-well immunoplates. The C-terminal domain of FAK(FAK-CD) was transfected through infection of the recombinant adenovirus. Also tyrosine phosphorylation of FAK was checked by immunoprecipitation of FAK followed by western blot analysis with anti-phosphotyrosine antibody. For evaluating the change of integrin expression, semi-quantitative reverse-transcription polymerase chain(RT-PCR) reactions were done after transfection of FAK-CD. RESULTS: We observed more increased expression of FAK in the chondroid cells than that in chondrocytes using western blotting. The level of attachment to type II collagen was significantly inhibited by blocking with the monoclonal antibody of integrin-beta1 and synthetic RGD peptides. Also adenovirus mediated transfection of FAK-CD resulted in inhibition of phosphorylation of FAK and significantly inhibited cell attachment in only JJ102. Integrin-beta1 antibody blocking after transfection with FAK-CD showed inhibition of cell attachment in more than 95% of all cells. The mRNA expression of both Integrin a2 and integrin a5 was increased but was not significant. Protein expression of integrin a2 and integrin a5 showed no changes. CONCLUSION: We found that the attachment of FAK-overexpressing cells could be mediated through integrin-beta1 receptor. We concluded that the modification of FAK expression will contribute to increase the cell attachment to biomaterials and regeneration of cartilage defects.