Enriched gene signatures are associated with aggressiveness in
-high breast cancers. NES represents the normalized enrichment score for the gene-set enrichment analyses. The ranked list metric was generated by calculating the signal-to-noise ratio, which is based on the difference of means scaled according to the standard deviation. The larger the signal-to-noise ratio, the more distinct the gene expression is for each phenotype, and the more the gene acts as a “class marker.” The Broad Institute Gene Set Enrichment Analysis website (http://www.broad.mit.edu/gsea) provides detailed information about this computational method. The heat maps show the enrichment of genes in the gene sets. Columns are individual samples, and rows represent each gene. Each cell in the matrix represents the expression level of a gene in an individual sample. Red indicates a high level of expression, and green indicates a low level of expression. RRM2-high was significantly associated with the following gene sets: A) Rhodes undifferentiated cancer gene signature , B) Sarrio’s epithelial-mesenchymal transition in breast cancer related to basal-like phenotype , C) Zhang’s Breast cancer progenitor gene signature , D) Ben-Porath proliferation gene signature , E), Chang’s Core Serum Response gene signature F) Naderi breast cancer prognosis (up) gene signature .