There is a clear correlation between aberrant Notch signalling and the triple negative phenotype, and multiple studies have identified roles for Notch signalling in TNBC that are not recapitulated in ER+ or HER2+ breast cancer (Lee et al., 2008a; Yamaguchi et al., 2008; Giuli et al., 2019). Here, ERBB2 is linked to breast carcinoma.