The median 90% effective maximal concentration (EC90) of BIM, a putative biomarker of chemosensitivity [17], was 0.08 ± 0.09 μM for CLL and not reached for all RS cases with the exception of RSVR3 (EC90: 0.73 μM; Fig. 1D), consistent with the presence of highly unprimed cell subpopulations within the RS tumor bulk. Here, BCL2L11 is linked to B-cell chronic lymphocytic leukemia.