Our data on Ephrin B3-EphA4 interaction and our preliminary data which suggests that blocking either EphA4 per se or Ephrin B3 in combination with EphA4 in fact cause cell death in certain NSCLC cells (Novak et al., unpublished data) is contrast to Saintigny et al., who found EphA4 blockade to inhibit migration [9]. The gene discussed is EPHA4; the disease is non-small cell lung carcinoma.