Fig. 1. HOXA3 induces endothelial cell migration and angiogenesis in vivo. (a) Semi-quantitative RT-PCR of a 900 bp product corresponding to HOXA3 in HMEC transfected with control or HOXA3 expression plasmid (upper panel). 250 bp ladder in the first lane represents from top to bottom: 1000 bp, 750 bp and 500 bp. Lower panel, western blot for the 46 kDa HOXA3/myc/His fusion protein expressed by HMEC-1 transfected with HOXA3 myc/His cDNA. (b) Migration of control or HOXA3-transfected HMEC in modified Boyden chamber coated with collagen I. As a positive control, 50 ng VEGF¹⁶⁵ was added to the lower chambers. Migration was assessed after 4 hours and results are expressed as the mean±s.d. **P<0.05 relative to migration of control cells. (c) CAM tissue (original magnification x15) 72 hours after application of control (ß-gal, left-hand panel) or HOXA3 expression plasmids (middle panel), or recombinant VEGF¹⁶⁵ (right-hand panel). (d) Quantification of angiogenesis induced by control or HOXA3 expression plasmids, or in the presence of 50 ng of VEGF¹⁶⁵. **P<0.05 compared with levels in control cells. Results are the mean±s.d. of 12 experiments.