Effect of nucleolin (NCL) knockdown on HB-19-induced signal transduction. Western blot analysis of phosphorylated SRC and ERK1/2 in HUVECs stimulated with 10 μM HB-19 for 15 minutes. The blots were stripped and re probed for HSC70. The last two bars of each diagram indicate HUVECs that were transiently transfected with siRNA targeting nucleolin. Results are expressed as % change relative to control and are mean values ± SE from at least 3 independent experiments.