ERBB4 and cancer: Although previous studies have shown associations between ERBB4 expression and different human cancers (Ferretti et al, 2006; Frey et al, 2010; Junttila et al, 2005; Kang et al, 2007; Maatta et al, 2006; Mill et al, 2011; Sartor et al, 2001), to date no links with tumour metastasis have been reported.