The p160 steroid receptor coactivator (SRC) family contains three members, SRC-1[1], SRC-2/GRIP1/TIF2 [2], [3] and SRC-3/Amplified in Breast Cancer-1 [4] that interact with multiple nuclear receptors (NRs) and other transcription factors to regulate gene transcription. This evidence concerns the gene NCOA2 and breast cancer.