JAG1 and breast cancer: For example, in a study of basal-like BC cells it was found that lipopolysaccharide (LPS) treatment of macrophages induced the expression of Jag1 in these cells; based on other findings provided in that study, the authors suggested that through such Jag1 up-regulation the macrophages could have led to Notch activation in cancer stem cells (CSCs) and then to their expansion [88] (Figure 1(A2)).