Semaphorin 3A Increases FAK Phosphorylation at Focal Adhesions to Modulate MDA-MB-231 Cell Migration and Spreading on Different Substratum Concentrations

Figure 1

Sema3A enhances cell migration at low coating concentrations of collagen but inhibits migration at high coating concentrations of collagen. ((a) and (b)) Representative images of MDA-MB-231 cells cultured on substrata coated with low (1.0 μg/mL), intermediate (10 μg/mL), and high (100 μg/mL) concentrations of collagen in the presence of 100 μg/mL IgG1 Fc control or Sema3A. Scale bar = 100 μm. ((c)–(e)) Cell migration as measured by average % area closure from cells cultured on different coating concentrations of collagen (c), fibronectin (d), or laminin (e) in the presence of IgG1 Fc control or Sema3A. Sema3A enhanced migration at low and intermediate coating concentrations of collagen by 59% and 58%, respectively, but inhibited migration by 40% at high coating concentrations of collagen. However, although Sema3A enhanced migration by 45% at low coating concentrations of fibronectin, there was no statistically significant reduction in migration at high coating concentrations of fibronectin. Overall, Sema3A did not have any significant effect on laminin. Data are presented as mean% area closure ± SEM from a minimum of three independent experiments. , , , and indicate statistical significance relative to IgG1 Fc control; two-sample -test.

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