Down expression of BAG3 increases apoptosis induced via Bax or Fas by IL-3 deprivation in hematopoietic cells. Furthermore, BAG3 down modulation is recently shown to enhance the apoptotic response to chemotherapy with alkylating agents through regulation of CHK2 and CDC2 proteins in human primary B chronic lymphocytic leukemia cells. Here, IL3 is linked to B-cell chronic lymphocytic leukemia.