The heatmap in Fig. 4A shows GSEA enrichment values (NES) for drug response signatures by cancer type, identifying differential responses by compound; positive NES values (i.e. enriched in the BUB1 high group) suggest that the responsive genes to the given drug are expressed in patients with a high expression of BUB1, while negative NES values indicate an enrichment in the BUB1 low group (hence, high BUB1 expression does not express drug responsive genes). Here, BUB1 is linked to cancer.