Heat map visualization of NB-hop gene expression in the Agilent262 test set. The expression values for each gene belonging to the NB-hop signature (rows) have been scaled and are represented by pseudo-colors in the heat map. Red color corresponds to high level of expression and blue color corresponds to low level of expression. NB patients (columns) belonging to the Agilent262 test set are divided into two groups according to NB-hop predictions. Age groups, INSS stage, MYCN status, event overall, event-free, TMM, ALT, p53/RAS gene mutations and NB-hop prediction are indicated on the top of the heat map with the relative color legend. The expression value of the 7 NB-hop genes was grouped by hierarchical clustering. The hierarchical clustering dendogram is shown on the left. NB-hop: neuroblastoma hypoxia outcome predictor; TMM: Telomere maintenance mechanisms; ALT: Alternative lengthening of telomeres; F: Favorable; UF: Unfavorable.