CD40LG and B-cell chronic lymphocytic leukemia: Proliferation centers are a key feature of CLL lymph nodes, where they are thought to be important sites of B-cell receptor (BCR) signaling and cellular proliferation.18,19 Surface IgM stimulation is known to induce MYC expression in CLL cells in vitro, which correlates with observations regarding increased MYC expression within CLL PCs.19,20 Despite the importance of these sites for CLL progression, and the role of MYC as a master regulator of metabolism,21 little is known about the metabolic events that occur within CLL PCs.