We explain this phenomenon through two mechanisms: (i) Exogenous miR-181b, by targeting the anti-apoptotic proteins MCL-1 and BCL-2, sensitizes CLL cells to the extrinsic apoptosis through CD8+ T cells; and (ii) miR-181b reduces the expression of IL10, which inhibits the production of cytokines that promote the generation of effector CTLs [11,34,35] (Figure 6G). Here, MCL1 is linked to B-cell chronic lymphocytic leukemia.