mRNA expression of the EGFR ligands AREG and EREG. A, Expression of AREG and EREG is significantly increased in the distal colorectum vs. proximal colon across the INTERMPHEN (n = 119 proximal and n = 236 distal colorectum) and TCGA COADREAD (n = 18 proximal and n = 19 distal/rectal). Log2FC and significance values obtained via DESeq2 analysis (see Materials and Methods). B, Expression of EREG is significantly increased in class 3 BRAF-mutant colorectal cancers vs. class 1 in the absence of a concomitant Ras mutation (P.adj < 0.005), which may reflect the distal colorectum bias of class 3 mutations. (Created with BioRender.com.)