LM-PmC (A and C) or GFP-PC-3 (B and C) cells were seeded on the upper side of a Transwell filter, and the number of cells that migrated to the other side of the filter was quantified. A and B, iRGD, non-CendR RGD peptides (CRGDC and RGDfV), or non-RGD CendR peptides (iNGR: CRNGRGPDC or RPARPAR) at a final concentration of 10 μM or PBS was added to both upper and lower wells. C, iRGD or CRGDC at a final concentration of 10 μM or PBS was added only to lower wells. Anti-NRP-1 b1b2 or control IgG was added to some of the wells. n = 3 per experiment. Non-treated columns were considered as 100%. Error bars, mean ± SEM; statistical analyses, ANOVA; *P < 0.05; **P < 0.01; ***P < 0.001. Statistics against the non-treated columns are shown unless otherwise noted.