CD24 and breast cancer: Our data show that in luminal-like MMTV-PyMT and in metaplastic Apc1572T/+ tumors that represent a model for a subtype of human triple negative basal-like breast cancers [48], CD24 can be upregulated during early tumorigenesis (Figs 1A, 1C, 1D and 2B–2D; S1 and S2 Tables).