We therefore tested the effect of GATA3 on populations of normal or cancer stem cells, as follows: 48 hours following transfection of GATA3 or control vector, hMEC or MCF7 cells were seeded in ultra-low attachment plates according to a published protocol [32], and floating spheres, representing progenitor [32] or tumor stem cells (tumor initiating cells (TICs)) [65], respectively, were counted after 10 days. Here, GATA3 is linked to cancer.