In the ER+ subtype of breast cancer, RUNX1 has been implicated as a tumour suppressor through the stabilization of Axis inhibition protein 1 (AXIN1) expression, but high RUNX1 expression correlates with poor prognosis in triple-negative breast cancers (Mercado-Matos, Matthew-Onabanjo & Shaw, 2017; Chimge et al., 2016). Here, RUNX1 is linked to triple-negative breast carcinoma.