GATA3 and breast cancer: We knocked down Gata3 in MMTV-PyMT tumor cells that were isolated and screened from MMTV-PyMT mammary tumors and were confirmed as Gata3 proficient (Gata3+/+) luminal type before and after transplantation into mammary fat pads (MFPs) of recipient mice [Fig. 1E, and details in [15, 16]].