ERBB2 and breast cancer: Recent studies have indicated that suppression of β4-integrin in the context of breast cancer, through shRNA approaches or deletion of its signalling domain, has a profound effect on tumorigenesis by reducing ErbB2 signalling thereby preventing proliferation and survival (Lipscomb et al., 2005; Bon et al., 2006; Guo et al., 2006; Yoon, Shin, & Lipscomb, 2006).