NOTCH1 and B-cell chronic lymphocytic leukemia: Additionally, Filomena et al. provided evidence that JAG1 is constitutively processed in CLL cells, and the activation of Notch1/2 is independent of the up-regulation of JAG1 levels.184 These findings offer new insights into Notch signaling in CLL cells and suggest that targeting the Notch signaling pathway could be developed as a novel therapeutic strategy for CLL.