This may be a “preprogrammed” mechanism for CLL cells’ survival in stimuli-poor peripheral blood, as FoxO1 and Rictor are upregulated in intraclonal CXCR4brightCD5dim subpopulations (Supplemental Figure 14A), the CLL cell subpopulation circulating in peripheral blood for an extended time (7, 23, 68). Here, RICTOR is linked to B-cell chronic lymphocytic leukemia.