Figure 7

Slit2N inhibits VEGF-C-enhanced growth, migration, and tube formation of L-LECs in a Robo4-dependent manner. (A) Proliferation of L-LECs transiently transfected with control siRNAs or Robo4-specific siRNAs as assessed by MTS assay after treatment with control, 10 nM Slit2N, VEGF-C [100 ng/ml]; or after preincubation with Slit2N, then VEGF-C. Data represent the mean ± SD of 3 independent experiments (**p < 0.01; NS: not statistically significant). (B) Transwell migration of L-LECs transiently transfected with control siRNAs or Robo4-specific siRNAs after treatment with control, 10 nM Slit2N, VEGF-C [100 ng/ml]; or after preincubation with Slit2N, then VEGF-C. Data represent the mean ± SD of 3 independent experiments (***p < 0.001; NS: not statistically significant). (C) Relative length of tubes formed by L-LECs transiently transfected with control siRNAs or Robo4-specific siRNAs as assessed by in vitro tube formation assay on ECM after treatment with control, 10 nM Slit2N, VEGF-C [100 ng/ml]; or after preincubation with Slit2N, then VEGF-C. Data represent the mean ± SD of 3 independent experiments (*p < 0.05; NS: not statistically significant). For panels A, B, and C, proliferative index, migration index, and relative tube length, respectively, were set to “1” for control-siRNA-transfected, untreated cells. Data for all other conditions were calculated relative to these controls.