To dissect its mechanisms of action and to further assess the role of CgA on CLL cell behavior we then studied the effect of CgA in the MEC1 xenograft model, which is based on the intravenous injection of human MEC1 CLL cells (stably transfected to express GFP) into Rag2−/−γc−/− mice [23], thus bypassing the intravasation process. Here, CGA is linked to B-cell chronic lymphocytic leukemia.