IFNB1 and breast cancer: Whereas in neuroblastoma cells, IFNβ induces apoptotic cell death through the intrinsic pathway by downregulation of phosphatidylinositol 3-kinase/AKT signaling, cytochrome C release and activation of procaspase 9 [18], induction of apoptosis in melanoma and breast cancer cells is mediated via the extrinsic signaling pathway and dependent on the expression of the death ligand TRAIL [19–20].