Interestingly, overnight culture of CLL cells resulted in a spontaneous increase in STAT3 association with the PRKCB promoter (Fig. 5b), and this corresponded with both an observed decrease in PRKCB promoter-associated SP1 (Figs 3b and 5c) and with the dynamics of PKCβII mRNA levels in CLL cells cultured overnight (Figs 1b and 5d). This evidence concerns the gene SP1 and B-cell chronic lymphocytic leukemia.