CTLA4 inhibits the B-cell proliferation/survival pathway at multiple levels by down-regulating key downstream molecules including transcription factors STAT1 and NFATC2, proliferation-associated c-Myc, and anti-apoptotic Bcl-2, resulting in decreased proliferation/survival of CLL cells (Figure 6). This evidence concerns the gene NFATC2 and B-cell chronic lymphocytic leukemia.