Fig. 3

Glutaredoxin 2c promotes invasion of human glioblastoma cells. A) Quantification of transmigrated glioblastoma cells using a Boyden chamber assay, different glioblastoma cell lines, as well as recombinant protein and siRNA to modulate Grx2 levels. B-E) U343-MGA (B) or GBM-18 (D) spheres with modulated Grx2 levels (down-regulation by siRNA, up-regulation by overexpression via a pExpress plasmid) were embedded in a 3D collagen matrix and invasion of cells after 72 h is shown, scale bars: 200 μm. C/E) Quantification of the areas of migrated cells (px²) based on B/D. F,G) U343-MGA, GBM-18 cells (F), and NG2⁺-cells (G) were treated with or without 2 μM recombinant Grx2c and BrdU⁺-cells were quantified. H) Fluorescent labelled U343-MGA cells transfected with either control siRNA or Grx2 siRNA were injected into zebrafish at the 1000 cell stage. Pictures show stills from supplemental movies 1 obtained by light sheet microscopy between 24 and 48 hpf. I) Quantification of invasion in 3 zebrafish embryos based on supplemental movies 2. *: p < 0.05; ***: p < 0.001 (Student's t-test).