MCL1 and B-cell chronic lymphocytic leukemia: The anti-tumor effect of this cluster in B-CLL is due to the direct targeting of the anti-apoptotic protein Bcl2 [165] as well as TP53, Cyclin Dependent Kinase 6 (CDK6) and Myeloid cell leukemia sequence 1 (MCL1), that is known as Bcl2-related [166].