In sections of CLL and other B-cell tumors in lymph nodes, spleens, and bone marrow, and as mimicked in stimulated suspension cultures, strong TCL1A expression in the resting cells was paralleled by near-complete losses of TCL1A protein in the fraction of Ki67+ proliferating paraimmunoblasts [12,28]. Here, TCL1A is linked to B-cell chronic lymphocytic leukemia.