As postulated, NSG mice transplanted with TCL1 Nfat2−/− CLL cells exhibited significantly accelerated disease and a markedly reduced life expectancy when compared to NSG mice transplanted with TCL1 CLL cells with intact NFAT2 expression (70 vs. 160 days) (Fig. 3i, j). Here, NFATC1 is linked to B-cell chronic lymphocytic leukemia.