Because multiple Bcl-2 anti-apoptotic members were found highly overexpressed in geminin overexpressing cells, we propose that geminin plays an important role in maintaining survival of aneuploid, chemo-resistant cells and that overcoming geminin overexpression-induced breast cancers, in vivo will require co-antagonism of several Bcl-2 anti-apoptotic proteins. Here, GMNN is linked to breast cancer.