Since Notch signaling and its crosstalks with many signaling pathways play an important role in breast cancer cell growth, migration, invasion, metastasis as well as angiogenesis [3], we hypothesized that a crosstalk between Notch, IL-1 and leptin signaling could impact on the expression of pro-angiogenic molecules, and induction of cell proliferation and migration in breast cancer. This evidence concerns the gene IL1A and breast cancer.