Figure 3: GALR2 promotes PNI.
From: Galanin modulates the neural niche to favour perineural invasion in head and neck cancer
(a) UM-SCC-1 cells (green) overexpressing GALR2 co-mingle with SH-SY5Y neuroblastoma cells (red) and induce more neuritogenesis (differentiation) than controls pcDNA, (two experiments, two replicates in each; scale bar, 100 μm). (b) UM-SCC-1-GALR2 cells are more invasive (red arrows) towards DRG than controls (UM-SCC-1-pcDNA) and induce neurite outgrowth (blue arrow; scale bar, 1 mm). (c) Knockdown of endogenous GALR2 in UM-SCC-1 cells, validated by immunoblot (left panel), inhibits invasion (right panel; two experiments, three replicates in each). (d) UM-SCC-1-GALR2 CAM tumours (green) are more invasive and induce neurite outgrowth (red; scale bar, 5 mm, n=6 in each group). (e) UM-SCC-1-GALR2 cell invasion (red arrow) and neurite outgrowth (blue arrow) are attenuated with antagonist anti-GAL antibody (iGAL; scale bar, 1 mm). (f) Invasion of UM-SCC-1-GALR2 (red arrow) and neurite outgrowth (blue arrow) are inhibited by M871 (designated iGALR2), but not scrambled peptide. (pcDNA n=3, GALR2 n=6, GALR2-M871 n=4, GALR2-Scr n=5; scale bar, 1 mm). (g) M871 (iGALR2) inhibits growth of UM-SCC-1-GALR2 CAM tumours (scale bar, 5 mm, Ctr n=7, iGALR2 n=8, Scr n=8). Area was quantified with ImageJ. b,e are representative of three independent experiments with three replicates in each. f is representative of two experiments. (*P<0.05, two-sample t-test; graph represents mean+s.d.).
