Targeting PZ and CXCR4 with siRNA results in decreased migratory capacity and endothelial tube formation <i>in vitro</i>.

<p>PZ and CXCR4 knock-down in unstimulated HUVECs as well as CXCR4 knock-down in PZ and SDF-1 stimulated HUVECs resulted in migration capacity comparable to that of ctrl after both 8 (<b>A</b>) and 24 hours (<b>B</b>). Data are given as box plots indicating the median with the 25^th and 75^th percentiles. Ø corresponds to unstimulated cells. ANOVA on ranks; $ p<0.05 vs. ctrl; n = 4 independent experiments. Representative images (<b>C</b>) and quantitative analysis (<b>D</b>) of capillary-like tube formation. HUVECs targeted with siRNA against PZ or CXCR4 showed significantly reduced capacity for capillary-like tube formation compared to ctrl. Addition of PZ or SDF-1 to CXCR4 siRNA targeted cells failed to restore endothelial tube formation. Data are given as box plots indicating the median with the 25^th and 75^th percentiles. Ø corresponds to unstimulated cells. ANOVA on ranks; $ p<0.05 vs. ctrl; n = 4 independent experiments.