MKNK1 and B-cell chronic lymphocytic leukemia: Based on these observations, we examined whether in CLL cells, Mcl-1 downregulation by Notch silencing was accompanied by effects on the expression and phosphorylation of eIF4E (Ser209), MNK1 (Thr197/202), and 4E-BP1 (Thr37/46 and Ser65).