The interaction between CacyBP/SIP and ERK1/2 inhibited phosphorylation of the Elk-1 transcription factor in the nuclear fraction of neuroblastoma NB2a cells and, interestingly, this effect was due to the phosphatase activity of CacyBP/SIP toward ERK1/2 [11]. This evidence concerns the gene MAPK3 and neuroblastoma.