Table 2 Description of GSEA metrics

Enrichment score (ES)

Reflects the degree to which proteins in a pathway are over-represented at the top or bottom of the ranked protein list.

Normalized enrichment score (NES)

A normalized version of the enrichment score that accounts for differences in pathway size. This is the primary statistic for comparing results across pathways.

False discovery rate (FDR)

The probability that a pathway with a given NES represents a false positive finding. An FDR cut-off of 5% was used to determine statistical significance in the present study.

Leading edge subset (LES) proteins

Proteins that appear in the ranked list at or before the point that the running ES reaches its maximum deviation from zero. These are the core proteins driving pathway enrichment. In the present study, LES proteins were used to group similar pathway findings into clusters (thus reducing redundancy and aiding with interpretation).