While some studies point to a direct role of NRP1 in tumour cell functions, a recent report showed that the ability of blocking NRP1 antibodies from inhibiting tumour growth in vivo was not dependent on the tumour cell expression of NRP1, or the direct anti-tumour effects of NRP1 blockade, but was mediated by an antiangiogenic effect on the tumour vasculature (Pan et al, 2007). This evidence concerns the gene NRP1 and neoplasm.