RBPJ and breast cancer: Besides its pivotal role in controlling transcription as a cofactor of CSL (CBF1/RBPJ-κ /Su(H) Lag1) family of DNA binding proteins, the ability of Notch to endow breast cancer cells with aggressive and stemness features results also from the interplay with several pathways, among them PI3K/Akt, Jak/STAT, NF-kappaB, ErbB2, Wnt, and HIF1 (Ranganathan et al, 2011).