RBBP4 and neuroblastoma: In an independent series of 42 primary NB cases, the transcript levels of RBBP4 were higher in NB specimens with MYCN amplification (P = 0.0149, unpaired t test), advanced INSS stages (P = 0.0002, unpaired t test), or poor differentiation (P = 0.0006, unpaired t test, Supplementary Fig. 9d), without significant difference in NB patients of varied age groups (P = 0.9693, unpaired t test, Supplementary Fig. 9d).