MCL1 and B-cell chronic lymphocytic leukemia: Interestingly, HG3-del(11q) BIRC3MUT CLL cell lines showed higher levels of BCL2 and BCL-xL, alongside to reduced levels of pro-apoptotic protein BAX, whereas no changes were observed regarding MCL1 or pro-apoptotic family members such as BIM, BAK, and NOXA (Fig. 2C; Supplementary Fig. S4a).