ENPP2 and Wilms tumor: Prior data from microarray experiments [4] had pointed to deregulation of RA signaling pathway genes (RARB, RARG, RARRES1, RARRES3, ENPP2, CRABP2, CTGF, RAMP, MYCN, EZH2, PRAME and IGFBP3; Additional file 1, Table S1) in Wilms tumors.