NF-kB activity is normally associated with an inhibition of apoptosis, and in fact has been shown to be induced in CLL cells by pro-survival microenvironmental stimulants like e.g. CD40L, BAFF; stromal cells or B-cell receptor stimulation [38], [87], [92]–[94]. Here, TNFSF13B is linked to B-cell chronic lymphocytic leukemia.