[Dynamic changes in focal adhesion kinase during cell migration induced by bFGF and the significance].

Cell migration plays an important role in repair of injury, angiogenesis, cancer metastasis and so on. In this paper the effects of basic fibroblast growth factor (bFGF) of different concentrations on ECV-304 cell migration, and the dynamic changes in focal adhesion kinase (FAK) were observed. The relationship between FAK and cell migration induced by bFGF was studied. A ECV-304 cell scratch wound model was established and the images of cell migration were quantitatively measured using a computer-assisted videomicroscopic system. The dynamic changes in FAK content (Western blot), FAK activity (immunoprecipitation plus Western blot) and FAK mRNA (RT-PCR) were measured in vitro. The expression of integrin alpha3 was investigated using immunocytochemical staining (ABC method). The results showed that bFGF produced a dual-phase regulatory effect on ECV-304 migration when the cell confluent areas reached 90%-95% in culture. It was found that compared with the control group (0 ng/ml bFGF), the cell migration was stimulated (P<0.05), inhibited (P<0.05) and unchanged when the cultured cells were treated with bFGF at the concentrations of 5, 10 and 15 ng/ml, respectively. The content and activity of FAK protein were markedly up-regulated in 5 ng/ml bFGF group and down-regulated in 15 ng/ml bFGF group, respectively. FAK mRNA expression came to the peak in 5 ng/ml bFGF group after 6 h culture and there was a significant difference compared with the control group. In various experimental groups there were no significant differences in the expression of integrin alpha3 compared with the control group according to the immunocytochemical staining. The results mentioned above suggest that different concentrations of bFGF have a dual-phase effect on the migration of cultured ECV-304 cells, which correlates positively with FAK content, activity and mRNA in cultured ECV-304 cell scratch wound model. The FAK plays an important role in the signal transduction pathway of cell migration induced by bFGF, while bFGF can regulate the content of FAK in ECV-304 cells at gene transcription level.