SLAMF1/CD150-silenced CLL-like Mec-1 cells or SLAMF1/CD150(lo) primary CLL cells were resistant to autophagy-activating therapeutic agents, such as fludarabine (a part of the FCR chemoimmunotherapy combination used for the treatment of CLL) and ABT-737, a BCL2 inhibitor. This evidence concerns the gene BCL2 and B-cell chronic lymphocytic leukemia.