IRF5 and breast cancer: To date, compelling evidence associates high risk of BC relapse only with loss of expression of the metastasis suppressors PEBP1, NM23-H1, and IRF5. NM23-H1 has been proposed to act as a general metastasis suppressor in various tumor types (Marino et al, 2013), while PEBP1 and IRF5 have been described as bona fide metastasis suppressor genes in BC (McHenry et al, 2008; Li et al, 2009; Bi et al, 2011).