Figure 2

Primary cells, breast cancer cells and four sub-populations of CD44⁺CD24⁺, CD44⁺CD24^-, CD44^-CD24^- and CD44^-CD24⁺ cells. Cells expanding from the tissue (A) showed at least two different shapes (epithelial and stromal) and became homogeneous after sub-culturing (B). These cells were sorted into four sub-populations of CD44^-CD24⁺ (C), CD44^-CD24^- (D), CD44⁺CD24^- (E) and CD44⁺CD24⁺ cells (F).