Fig. 6

Characterization of angiogenic effects and compensatory changes of signaling pathways after STAT1 knockdown. (A) Spheroid sprouting assay using HUVECs: Cells transfected with control siRNA or STAT1 siRNA were treated under following conditions: EBM (negative control), IL-11, VEGF (positive control), IL-11+VEGF. RSL = Relative Sprouting Length. N = 4 independent experiments each consisting of 14-22 spheroids per group and experiment, statistical testing: Kruskal-Wallis Test adjusted for multiple testing, *p<0.05. Scale bar 20 µM. (B) Spheroid sprouting assay using HUVECs: Cells transfected with control siRNA or STAT1 siRNA were treated under following conditions: EBM (negative control), IL-11+sIL-11Rα, VEGF (positive control), IL-11+sIL-11Rα+VEGF. RSL = Relative Sprouting Length. N = 3 independent experiments each consisting of 11-20 spheroids per group and experiment, statistical testing: Kruskal-Wallis Test adjusted for multiple testing, *p<0.01. Scale bar 20 µM. (C) Semi-quantitative Western blot analysis of signaling molecules in HUVECs after STAT1 knockdown and treatment under the conditions mentioned in (A) for 15 min. Interleaved box and whiskers: the whiskers represent the minimum and maximum values while the line in between represents the median value. N = 3 independent experiments. (D) Semi-quantitative Western blot analysis of signaling molecules in HUVECs after STAT1 knockdown and treatment under the conditions mentioned in (B) for 15 min. Interleaved box and whiskers: the whiskers represent the minimum and maximum values while the line in between represents the median value. N = 3 independent experiments