CsA promotes the phosphorylation of EGFR in a CXCL12/CXCR4 axis-dependent manner.

<p><b>A</b>: Primary human trophoblast cells were treated with neutralizing antibody against CXCL12 (40 µg/ml) or CXCR4 (20 µg/ml) for 48 h, and then treated with 1 μM CsA in 1640 complete medium supplemented with 10% FBS for 1 h and subjected to immunofluorescence analysis to analyze the levels of phosphorylated EGFR and total EGFR. Scale bar, 25 μm. <b>B</b>: JEG-3 cells were transfected with CXCR4 siRNA (125 nM), or CXCL12 siRNA (125 nM), or non-targeting siRNA control, or treated with neutralizing antibody against CXCL12 (40 µg/ml) or CXCR4 (20 µg/ml) for 48 h, and then treated with 1 μM CsA in 1640 complete medium supplemented with 10% FBS for 1 h, and subjected to western blotting to analyze the levels of phosphorylated EGFR and total EGFR. A typical blot (the lower panels) and densitometry analysis of the ratio of phosphorylated EGFR to total EGFR (the upper panels) are shown. Data are presented as mean ± SEM of three independent experiments. *P<0.05, compared to the control.