FCER2 and B-cell chronic lymphocytic leukemia: This leads to the proteolytic cleavage of S2 by ADAM10 metalloprotease and subsequently of S3 by γ-secretase followed by translocation of the NOTCH intracellular domain (NOTCHIC) to the nucleus, where it acts as context-dependent transcription factor on genes like FCER2 (CD23) in CLL cells [5].