The expression of genes associated with tumor promotion such as Snap29 (30), Mcoln1 (31) and Nek6 (32) was up-regulated in peritoneal CLL cells from TCL1-Tg mice compared to CLL cells from TCL1-Tg BAFF-/- mice (Figure 6C). The gene discussed is TNFSF13B; the disease is B-cell chronic lymphocytic leukemia.