Since over-expression or knockdown of NDRG1 suppressed or promoted the expression of VEGF and MMP-9 in NB cells, respectively (Figure S3), and combining the evidence that there was no FOXD3 binding site within their promoters, we ruled out the possibility that FOXD3 might directly regulate the expression of VEGF or MMP-9. Here, NDRG1 is linked to neuroblastoma.