IL21 and B-cell chronic lymphocytic leukemia: In an attempt to identify molecules involved in the anti-proliferative effect of AKT inhibition, the same CLL samples were co-cultured with CD154-expressing fibroblasts in the presence of IL-21 with or without AZD5363 (10 μM) for 24 h, 48 h and 72 h and analysed by Western blotting for the expression of key molecules involved in cell-cycle regulation.