Consistently, MVD is remarkably increased in the mammary tumors with transgenic NCOA1 overexpression in Tg(MMTV-NCOA1) × Tg(MMTV-TVA/RCAS-PyMT) mice versus mammary tumors with normal Ncoa1 expression in Tg(MMTV-TVA/RCAS-PyMT) mice. This evidence concerns the gene NCOA1 and breast cancer.