NOTCH1 and cancer: Likewise, in breast cancer, PIN1 increased Notch1 cleavage and N1IC and N4IC stability by inhibiting FBXW7-dependent proteasomal degradation, whereas PIN1 silencing allowed to reduce the GSI dose necessary to suppress cell growth and CSC selection and to sensitize cancer cells to chemotherapeutic agents in vitro and in vivo [330,331].