Fig. 5

VEGF receptor-2 antagonist Vatalanib inhibited HCT116 induced tumor angiogenesis in tg(fli1:EGFP) zebrafish embryos.

A–A3, Overall morphology of 96 hpf embryos after injection of 1–4 nl of Matrigel (A, B) or Matrigel/HCT116 solution (A2, A3, B2, B3) in the perivitelline space at 48 hpf. Directly after HCT116 tumor cell injection embryos were incubated in presence of 0.1 μM Vatalanib (A3, B3) or DMSO (A, A2, B, B2) for additional 48 hours. Red boxes indicate regions of pictures shown in (B–B3). B–B3, HCT116 induced angiogenesis as indicated by ectopic vessel formation originated from the subintestinal venous plexus (SIV) was analyzed at 96 hpf in tg(fli1:EGFP) embryos. Injection of HCT116 tumor cells led to strong ectopic vessel formation (asterisks) that was completely inhibited in Vatalanib treated zebrafish embryos. C–C2, Quantifications with S.D. of at least 30 embryos per group. For cumulative sprouting-length all sprouts of the same number of embryos per group were summed, (C2) represents means of three independent experiments with S.D. D–D2, Effect of Vatalanib on physiological angiogenesis in 48 hpf tg(fli1:EGFP) embryos. Embryos were incubated with DMSO (D) or 0.1 μM Vatalanib (D2) immediately after fertilization. Incubation with Vatalanib completely inhibited formation of ISV, DLAV and PL. Black scale bars: 300 μm; white scale bars: 100 μm. *P<0.05, **P<0.01, ***P<0.001.