Bendamustine- (p = 0.021) or combination-treated (p = 0.017) MEFs lacking MCL1 had significantly higher apoptotic cells compared to wild-type MEFs (Figure 6); indicating that the combination regimen potently downregulates Mcl-1 and thus enhance the apoptosis in CLL cells. Here, MCL1 is linked to B-cell chronic lymphocytic leukemia.