Elsarraj et al. (2015) [81] showed a role for BCL9 in the transition from in situ to invasive ductal breast carcinoma and reported that BCL9 knockdown is able to inhibit the proliferation, migration, and invasion of ductal carcinoma in situ cells in vitro and in vivo breast cancer models. The gene discussed is BCL9; the disease is ductal breast carcinoma in situ.