EGFR and cancer: This gene appears in the ErbB signaling pathway as the effector of two different paths, both selected as commonly significant, although with different directional behaviour: while ErbB signaling pathway: STAT5A is unidirectional, being down-activated in all three cancers, ErbB signaling pathway: STAT5A* is bidirectional, being up-activated in KIRC and down-activated in BRCA and LUAD, see Fig. 2a.